Power-assisted mechanical continuously variable transmission

Abstract

The present disclosure provides a continuously variable transmission including: a driven clutch; a drive clutch operatively coupled to the driven clutch, the drive clutch including a stationary wheel, a movable wheel positioned adjacent the stationary wheel along a common axis defined by the shaft and operable to translate axially relative to the stationary wheel, and a load member; a belt extending between the driving clutch and the driven clutch; and an actuator coupled to the movable wheel driving the clutch, the actuator operable to apply a force to the movable wheel in a direction substantially along or parallel to the common axis.

Description

[0001] Cross - reference to related applications

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 623,857, filed on January 23, 2024, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] This disclosure relates primarily to devices, systems, and methods for changing the transmission ratio of a continuously variable transmission. More specifically, this disclosure relates to devices, systems, and methods for providing an input for changing the position of a movable pulley of a mechanical continuously variable transmission. Background Art

[0004] Continuously variable transmissions (“CVTs”) are used in many vehicles. Mechanical CVTs are easier and less expensive to manufacture than alternative CVTs such as hydraulic and electronic CVTs. Rubber - belt CVTs are also less expensive to manufacture than steel - belt CVTs. However, one disadvantage of traditional mechanical rubber - belt CVTs is that once installed, the CVT is adjusted to a specific setting and cannot be changed during vehicle operation. Summary of the Invention

[0005] Various embodiments of a CVT are provided herein that include an actuator for modifying the CVT ratio of the CVT via an input from a system or a user.

[0006] According to one example (“Example 1”), a continuously variable transmission includes: a driven clutch; a driving clutch operatively coupled to the driven clutch, the driving clutch including a stationary pulley, a movable pulley, and a load member, the movable pulley being positioned adjacent the stationary pulley along a common axis defined by a shaft and being operable to translate axially relative to the stationary pulley; a belt extending between the driving clutch and the driven clutch; and an actuator coupled to the movable pulley of the driving clutch, the actuator being operable to apply a force to the movable pulley in a direction substantially along or parallel to the common axis.

[0007] According to another example (“Example 2”), and further according to Example 1, the actuator is one of a pneumatic actuator, a hydraulic actuator, and an electromagnetic actuator.

[0008] According to another example (“Example 3”), and further according to Example 1, the actuator is coupled to the shaft.

[0009] According to another example (“Example 4”), and further according to Example 3, the CVT includes a star nut, wherein the actuator includes a piston operatively coupled to the star nut and a cylinder coupled to the movable pulley.

[0010] According to another example (“Example 5”), and further according to Example 4, a chamber is defined between the piston and the movable wheel.

[0011] According to another example (“Example 6”), and further according to Example 5, the piston is positioned fixedly relative to the shaft, and the cylinder is axially movable relative to the shaft.

[0012] According to another example (“Example 7”), and further according to Example 6, the actuator includes a nozzle fluidly coupled to the chamber.

[0013] According to another example (“Example 8”), and further according to Example 7, the nozzle is coupled to the piston, and wherein the piston and the star nut define a passage such that the nozzle is fluidly coupled to the chamber via the passage.

[0014] According to one example (“Example 9”), a vehicle includes: a frame that defines an operator area; a plurality of ground members configured to support the frame; a powertrain assembly supported by the frame, the powertrain assembly including: an engine operatively coupled to at least one of the plurality of ground members; and a continuously variable transmission driven by the engine, the continuously variable transmission including: a driven clutch; a drive clutch operatively coupled to the driven clutch, the drive clutch including a stationary wheel, a movable wheel, and a load member, the movable wheel being positioned adjacent to the stationary wheel along a common axis defined by a shaft and being operable to axially translate relative to the stationary wheel; a belt extending between the drive clutch and the driven clutch; and an actuator coupled to the movable wheel of the drive clutch, the actuator being operable to apply a force to the movable wheel in a direction substantially along or parallel to the common axis.

[0015] According to another example (“Example 10”), and further according to Example 9, the continuously variable transmission includes: a star nut coupled to the shaft; a piston of the actuator coupled to the star nut, wherein the piston is positioned fixedly relative to the shaft; a cylinder of the actuator coupled to the movable wheel, wherein the cylinder is axially movable relative to the shaft, and wherein a chamber is defined between the piston and the movable wheel by the cylinder; and a nozzle of the actuator coupled to the piston and fluidly coupled to the chamber.

[0016] According to another example (“Example 11”), and further according to Example 10, the vehicle further includes a pressurized fluid source coupled to the actuator.

[0017] According to another example (“Example 12”), and further according to Example 11, the vehicle further includes a controller operatively coupled to at least one of the pressurized fluid source and the actuator, the controller being operable to cause the actuator to actuate based on a predetermined condition.

[0018] According to another example (“Example 13”), and further according to Example 12, the predetermined condition includes at least one of the speed of the grounding member and the throttle position.

[0019] According to another example (“Example 14”), and further according to Example 12, the controller includes at least a first driving configuration and a second driving configuration, wherein the controller causes the actuator to apply a first force to the movable wheel based on a first predetermined condition when in the first driving configuration, and to apply a second force to the movable wheel based on the first predetermined condition when in the second driving configuration, wherein the first force is different from the second force.

[0020] According to another example (“Example 15”), and further according to Example 12, the controller is configured to limit the rate of change of the force applied by the actuator based on at least one of the speed of the grounding member and the throttle position.

[0021] According to another example (“Example 16”), and further according to Example 11, the pressurized fluid source includes one of air and hydraulic oil.

[0022] According to another example (“Example 17”), and further according to Example 11, the vehicle further includes a fluid line coupling the pressurized fluid source and the actuator, wherein the actuator is positioned within the profile of the belt, and the pressurized fluid source is positioned within the profile of the belt or extends through the profile of the belt such that the belt can be removed without removing the fluid line or the actuator.

[0023] According to another example (“Example 18”), and further according to Example 10, at least one of the piston and the star nut defines a passage such that when the drive clutch shifts to engage the belt, the nozzle is fluid-coupled to the chamber via the passage, and wherein the passage is positioned to discharge to the atmosphere when the drive clutch is in the zero gear position.

[0024] According to another example (“Example 19”), and further according to Example 9, the continuously variable transmission includes: a star nut coupled to the shaft; a piston of the actuator coupled to the star nut, wherein the piston is fixedly positioned relative to the shaft; a cylinder of the actuator coupled to the movable wheel, wherein the cylinder is axially movable relative to the shaft, and wherein a chamber is defined only between the piston and the cylinder; and a nozzle of the actuator coupled to the piston and fluid-coupled to the chamber.

[0025] According to another example (“Example 20”), and further according to Example 18, the actuator is a removable cylinder such that the actuator and the pressurized fluid source do not require bleeding when reinstalled.

[0026] The foregoing examples are merely examples and should not be construed as limiting or otherwise narrowing the scope of any inventive concept provided by the present disclosure. Although multiple examples are disclosed, other embodiments will become apparent to those skilled in the art from the following detailed description that illustrates and describes the illustrative examples. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this application. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the present disclosure.

[0028] Figure 1 is a front perspective view of a vehicle according to one embodiment;

[0029] Figure 2 is a rear perspective view of a vehicle according to one embodiment;

[0030] Figure 3 is a left side view of a vehicle according to one embodiment;

[0031] Figure 4 is a right side view of a vehicle according to one embodiment;

[0032] Figure 5 is a top view of a vehicle according to one embodiment;

[0033] Figure 6 is a front view of a vehicle according to one embodiment;

[0034] Figure 7 is a rear view of a vehicle according to one embodiment;

[0035] Figure 8 is a perspective view of a CVT with an actuator according to one embodiment;

[0036] Figure 9 is a side view of a CVT with an actuator according to one embodiment;

[0037] Figure 10 is an exploded view of a CVT with an actuator according to one embodiment;

[0038] Figure 11 is an exploded view of a CVT drive clutch according to one embodiment;

[0039] Figure 12 is an exploded view of a CVT actuator according to one embodiment;

[0040] Figure 13 is a cross-sectional view of a CVT actuator and a drive clutch according to one embodiment;

[0041] Figure 14 is a cross-sectional view of a CVT actuator and a drive clutch in a zero gear position according to an embodiment;

[0042] Figure 15 is a cross-sectional view of a CVT actuator and a drive clutch when the actuator is actuated and pressure is applied to change the CVT ratio according to an embodiment;

[0043] Figure 16 is a partial perspective cross-sectional view of a cylinder, a star nut, and a nozzle according to an embodiment;

[0044] Figure 17 is a cross-sectional view of a nozzle for introducing fluid into an actuator according to an embodiment;

[0045] Figure 18 is a perspective view of a fluid line related to the cover of a CVT according to an embodiment;

[0046] Figure 19 is an alternative arrangement cross-sectional view of an actuator configured to vent to the atmosphere in a zero gear according to an embodiment;

[0047] Figure 20 is a schematic diagram of a CVT and components for controlling a CVT actuator according to an embodiment;

[0048] Figure 21 is a schematic diagram of a powertrain according to an embodiment;

[0049] Figure 22 is an alternative embodiment cross-sectional view of a CVT actuator including a solenoid according to an embodiment;

[0050] Figure 23 is a pressure diagram of a CVT actuator in a sport driving mode according to an embodiment;

[0051] Figure 24 is a pressure diagram of a CVT actuator in a standard driving mode according to an embodiment;

[0052] Figure 25 is a pressure diagram of a CVT actuator in a comfort driving mode according to an embodiment;

[0053] Figure 26 is a pressure rate change diagram of a CVT actuator according to an embodiment;

[0054] Figure 27 is an alternative CVT perspective view according to an embodiment;

[0055] Figure 28Is a perspective view of the outer housing of a CVT according to an embodiment;

[0056] Figure 29 Is according to an embodiment along Figure 27 The cross-sectional view of the CVT in the unactuated position taken along line 29-29 in Figure 27 ;

[0057] Figure 30A Is according to an embodiment at Figure 29 Separate views of partial cross-sections of Figure 29 Taken at cross-sections 30A, 30B of

[0058] Figure 30B Is according to an embodiment at Figure 29 The cross-sections 30A, 30B of Figure 29 Separate views of partial cross-sections of

[0059] Figure 31 Is according to an embodiment along Figure 27 The cross-sectional view of the CVT in the actuated position taken along line 29-29 in Figure 27 ;

[0060] Figure 32 Is according to an embodiment at Figure 30A The cross-section 32 of Figure 29 Separate views of partial cross-sections of

[0061] Figure 33 Is according to an embodiment along Figure 27 The line 33-33 of Figure 27 Cross-sectional view of the rotating member of the CVT actuator assembly;

[0062] Figure 34 Is a perspective view of the sleeve member of the CVT actuator assembly according to an embodiment;

[0063] Figure 35 Is a perspective view of the coupling member of the CVT actuator assembly according to an embodiment; and

[0064] Figure 36 Is a side view of the CVT actuator assembly according to an embodiment. Detailed Description

[0065] Definitions and Terms

[0066] The present disclosure is not intended to be read in a limiting manner. For example, the terms used in this application should be construed broadly in the context of the meanings that would be given to such terms by those skilled in the art.

[0067] For the term of imprecision, “about” and “approximately” may be used interchangeably to refer to a measurement that includes the stated measurement and also any measurement that is reasonably close to the stated measurement. As understood and readily determinable by one of ordinary skill in the relevant art, a measurement that is reasonably close to the stated measurement deviates from the stated measurement by a reasonably small amount. For example, such deviation may be attributable to measurement error, differences in measurement and / or manufacturing equipment calibration, human error in reading and / or setting the measurement, minor adjustments made to optimize performance and / or structural parameters in view of measurement differences associated with other components, particular implementation scenarios, imprecise adjustment and / or manipulation of an object by a person or a machine, etc. In cases where it is not readily determinable by one of ordinary skill in the relevant art what such reasonably small difference value is, the terms “about” and “approximately” may be understood to mean ±10% of the value. Detailed Description

[0069] Those skilled in the art will readily understand that various aspects of the present disclosure can be implemented by any number of methods and apparatuses configured to perform the intended functions. It should also be noted that the drawings referred to herein are not necessarily drawn to scale and may be exaggerated to illustrate various aspects of the present disclosure, and in this regard, the drawings should not be construed as limiting.

[0070] See Figures 1 to 7 , which shows an exemplary embodiment of a multi-purpose vehicle 2. The vehicle 2 is configured for off-road operation. The vehicle 2 includes a plurality of ground engaging members 4, illustratively front wheels 6 and rear wheels 8. In one embodiment, one or more of the ground engaging members 4 may be replaced with tracks, such as the Prospector II tracks available from Polaris Industries Inc., 2100 Highway 55, Medina, Minnesota 55340, or with non-pneumatic tires, such as those shown in U.S. Patent No. 8,176,957 and U.S. Patent No. 8,104,524, the entire disclosures of which are hereby expressly incorporated by reference. It should be understood that the embodiments discussed herein may be implemented for any number of vehicles, including snow vehicles, such as snowmobiles, motorcycles, side-by-side vehicles, all-terrain vehicles, etc.

[0071] The vehicle 2 also includes a lower frame assembly 10 supported by the ground engaging members 4, and the lower frame assembly 10 extends along the longitudinal centerline CL of the vehicle 2. The lower frame assembly 10 includes a front portion 12, a rear portion 14, and an intermediate portion 16 extending therebetween. Additionally, the vehicle 2 includes an upper frame assembly 19 extending vertically above the lower frame assembly 10 (more particularly, at least the intermediate portion 16 of the lower frame assembly 10). The lower frame assembly 10 supports a rear cargo support area 17 and a body 18, and the body 18 includes a plurality of body panels.

[0072] The vehicle 2 further includes an operator area 20, and the operator area 20 includes seats 22 for one or more passengers. The upper frame assembly 19 can be positioned generally around the operator area 20 such that the seats 22 are at least partially surrounded by the upper frame assembly 19. Additionally, side nets or doors 29 can be positioned along the sides of the operator area 20 and the seat 22. Exemplarily, the seat 22 includes an operator seat and a passenger seat. However, the seat 22 can also include rear seats for additional passengers. The seat 22 can include a seat back 24 and a seat bottom 26 for at least the operator and the passenger.

[0073] The operator area 20 further includes a plurality of operator controls 28, such as a steering wheel 27, through which the operator can provide inputs for operating the vehicle 2. Additionally, the steering assembly including the steering wheel 27 can be configured to turn 1.5 turns to lock. The various operator controls including the steering assembly are further described in International Patent Application No. PCT / US13 / 64516, filed on October 11, 2013, the entire disclosure of which is expressly incorporated herein by reference. The operator area 20 and the controller 28 can also include an HVAC system to enhance the comfort of the operator and the passengers.

[0074] See Figure 7 , the vehicle 2 includes a rear suspension assembly 37, as Figure 7 shown, the rear suspension assembly 37 includes shock absorbers 39. In one embodiment, the shock absorbers 39 can be internal bypass shock absorbers, as disclosed in International Patent Application No. PCT / US13 / 64516, filed on October 11, 2013, the entire disclosure of which is expressly incorporated herein by reference.

[0075] The vehicle 2 further includes a powertrain assembly 70, which is supported by the rear portion 14 of the lower frame assembly 10 and includes an engine 72, a shift transmission 74, and a continuously variable transmission (“CVT”) 100. In some embodiments, the powertrain assembly 70 can further include a forced air inducer, such as a gas supercharger (not shown). In one embodiment, the gas supercharger can be a turbocharger. However, alternatively, the gas supercharger can also be a supercharger or any other similar device.

[0076] See Figures 8 to 10, a CVT 100 is shown in the figure. The CVT 100 includes an inner housing 102 and an outer housing (not shown). The CVT 100 includes a primary or drive clutch or pulley 110, a secondary or driven clutch or pulley 112 located within the inner housing 102 and the outer housing, and a belt 116 extending therebetween. The drive clutch 110 is rotatably coupled to the crankshaft (not shown) of the engine 72. The driven clutch 112 is rotatably coupled to the input shaft 118 of the shift transmission 74 and is rotatably coupled to the drive clutch 110 via the belt 116. The belt 116 may be made of a polymeric material such as rubber and may also include reinforcing members such as metal cords or other reinforcing materials. In one embodiment, the belt 116 may comprise a metal material, for example, the belt 116 may be a chain. In cross-section, the belt 116 may generally define a "V" shape. The belt 116 is configured to contact the drive clutch 110 and the diameter of the belt 116 expands to contact the driven clutch 112.

[0077] As Figures 8 to 11 shown, the drive clutch 110 includes a movable pulley 120 and a stationary pulley 122. The movable pulley 120 is positioned adjacent to the outer housing (not shown) of the CVT 100, and the stationary pulley 122 is positioned adjacent to the inner housing 102 of the CVT 100. The stationary pulley 122 includes a central opening 124 for engaging with the first spline portion 126 of the rod 123. The rod 123 includes a tapered space 125 for engaging with the crankshaft 84 of the engine 72. It should be understood that other non-spline embodiments may also be similarly applicable, including cast wheels. The rod 123 also includes a second spline portion 128 for engaging with the spline portion 152 of the star wheel 132. During the operation of the CVT 100, the stationary pulley 122 remains in a fixed position and does not move relative to the rod 123.

[0078] In contrast, the movable pulley 120 of the drive clutch 110 is configured to move laterally relative to the stationary pulley 122 so as to engage with the belt 116 and achieve various drive ratios. Washers 148 and bearings 150 are positioned between the stationary pulley 122 and the movable pulley 120 to define a belt groove or path for the belt 116. Since the diameter of the central opening 124 is smaller than the diameters of the washers 148 and bearings 150, the washers 148 and bearings 150 are not located within the central opening 124 of the stationary pulley 122.

[0079] The movable pulley 120 includes a tower or base member 130, an intermediate member positioned adjacent to the tower member 130, a load member or star wheel member 132, and a cover member 134 positioned adjacent to the star wheel member 132 such that the star wheel member 132 is located between the tower member 130 and the cover member 134. The cover member 134 is coupled to the tower member 130 via fasteners 144 on the tower member 130. The cover member 134 includes a central opening 154.

[0080] The movable pulley 120 also includes a plurality of counterweights (exemplarily, flyweights 136) that are rotatably coupled to the tower member 130 by pins 138 and fasteners 140. The flyweights 136 are centrifugal counterweights that can pivot radially to laterally move or slide the movable pulley 120 relative to the stationary pulley 122. Various embodiments of the tower member 130 and the flyweights 136 are within the scope of the disclosure provided herein.

[0081] As Figure 11 shown, the star wheel member 132 includes a splined central opening 152, a plurality of corners or bars 156, and a plurality of positioning or location members 142. Since the splined central opening 152 engages the bar 123 coupled to the crankshaft, the star wheel member 132 is configured to transfer torque from the crankshaft to the movable pulley 120. Exemplarily, the star wheel member 132 has a generally triangular shape defining three bars 156, and each location member 142 is coupled to one of the bars 156 of the star wheel member 132. Like the stationary pulley 122, the movable pulley 120 also engages the bar 123. More particularly, the splined central opening 152 of the star wheel member 132 engages the second splined portion 128 of the bar 123.

[0082] During operation of the CVT 100, since the distal end of the crankshaft is received within the tapered space 125 of the bar 123, the drive clutch 110 rotates with the crankshaft via the bar 123. Under various operating conditions of the vehicle 2, the drive clutch 110 rotates at a speed that causes the flyweights 136 to pivot about the pins 138. The centrifugal force on the flyweights 136 causes the flyweights 136 to pivot or rotate radially against the bearings of the star wheel member 132. This movement of the flyweights 136 applies a force to the movable pulley 120 such that the movable pulley 120 laterally slides or translates relative to the stationary pulley 122 along the sleeve member 206 and the bearings 150. In this way, the radial position of the belt 116 on the movable pulley 120 and the stationary pulley 122 can be adjusted to accommodate various operating conditions of the vehicle 2, thereby producing various drive ratios. During operation, the drive clutch 110 is configured to move between an open position (as Figure 14 shown) and a closed position, in which the movable pulley 120 and the stationary pulley 122 are close to each other and the movable pulley 120 cannot continue to move towards the stationary pulley 122. The movement of the movable pulley 120 can be controlled electronically, mechanically, or hydraulically. The rotation of the belt 116 caused by the drive clutch 110 drives the driven clutch 112.

[0083] Turning to Figures 12 to 17In the discussion, the CVT 100 includes an actuator 300 that allows the auxiliary CVT 100 (i.e., a mechanical CVT) to adapt to various CVT ratios (e.g., transmission ratios) of various mechanical systems that exceed the tuned transmission ratios inherent in the provided system. As discussed, the CVT 100 includes a driving clutch 110 and a driven clutch 112 operatively coupled together. The driving clutch 110 includes a stationary pulley 122 and a movable pulley 120, and the movable pulley 120 is positioned adjacent to the stationary pulley 122 along a common axis CA defined by a shaft or rod 123. The movable pulley 120 is operable to translate axially relative to the stationary pulley 122. The driving clutch 110 further includes a load member or star wheel 132. The CVT 100 includes a rubber belt 116 that extends between the driving clutch 110 and the driven clutch 112. The actuator 300 is coupled to the movable pulley 120 of the driving clutch 110. The actuator 300 is operable to apply a force to the movable pulley 120 in a direction substantially along or parallel to the common axis CA. By applying this force, the actuator 300 can change the CVT ratio such that it exceeds that of the previously described typical mechanical systems. This allows the system or user to control the CVT ratio based on the control of the actuator 300 and based on existing components (such as a spring 131 and a shift weight 136) that adjust the CVT ratio based on physical conditions such as speed. The actuator 300 can be set to manipulate the effects of the CVT 100 while maintaining typical rubber belt CVT components and calibration (e.g., belt engagement). In some embodiments, the actuator 300 can be fine-tuned to provide additional effects in addition to minor inputs (e.g., by assisting or causing belt engagement). In some embodiments, various actuators can be implemented, including but not limited to pneumatic, hydraulic, and electromagnetic actuators.

[0084] According to some embodiments, a portion of the actuator 300 is coupled to a sleeve member 206 (e.g., a star nut), wherein the sleeve member 206 is coupled to the rod 123. Since the movable pulley 120 is able to move relative to the sleeve member 206 and the actuator 300 is coupled to the sleeve member 206 and contacts the movable pulley 120 to apply a force, in some embodiments, the sleeve member 206 and its associated support components provide an anchoring point for the actuator 300 and facilitate actuator support to apply pressure to the movable pulley 120. The length of the sleeve member 206 is designed such that the sleeve member 206 extends beyond the movable pulley 120 to provide a mounting location for the actuator 300. In some embodiments, the sleeve member 206 includes internal threads that are configured to receive the threads of the actuator 300.

[0085] According to some embodiments, the actuator 300 includes a piston 302, the piston 302 being operatively coupled to the sleeve member 206; and a cylinder 304, the cylinder 304 being coupled to the movable wheel 120. The piston 302 is fixedly coupled to the sleeve member 206 such that when the movable wheel 120 moves relative to the sleeve member 206, the movable wheel 120 also moves relative to the piston 302. The cylinder 304 is fixedly coupled to the movable wheel 120 such that the cylinder 304 moves relative to both the piston 302 and the sleeve member 206. A chamber 306 is defined by the cylinder 304 and, in at least some embodiments, the chamber 306 is defined between the piston 302 and the movable wheel 120 (such as the cover member 134). By providing a fixed piston and a movable cylinder, the encapsulation of the actuator 300 is reduced.

[0086] The piston 302 may define various components of the actuator 300. For example, in some embodiments, the piston 302 defines a threaded coupling portion 310 as described above, the coupling portion 310 being configured to couple to the internal thread of the sleeve member 206. The piston 302 also includes a head or crown 312. The crown 312 includes a seal or gasket 314 for sealing with the cylinder 304. The crown 312 also provides a surface that defines at least a portion of the chamber 306. The crown 312 may extend from the coupling portion 310 (as an integral part thereof or coupled to the coupling portion 310). The piston 302 also includes a swivel joint housing 316 for receiving a swivel joint 318. The swivel joint housing 316 and the swivel joint 318 (such as a nozzle) facilitate the coupling of a rotating part (such as the drive clutch 110) and a non-rotating part (such as an air line for delivering pressurized air to the chamber 306). The swivel joint 318 is fixed and supports the air line with a ball bearing and may be sealed against the swivel joint housing 316. O-rings and snap rings may seal and fix the components to each other. The swivel joint or nozzle 318 is fluidly coupled to the chamber 306.

[0087] Pressurized air flows from a pressurized air source through the swivel joint 318, the piston 302, and the sleeve member 206 and is delivered into the chamber 306. Channels 320 are defined in the piston 302 and the sleeve member 206. For example, the swivel joint 318 and the swivel joint housing 316 are positioned such that the swivel joint 318 is in fluid communication with the channel 320. In some embodiments, the channel 320 extends through the coupling portion 310 towards the sleeve member 206. The channel 320 may extend radially outward perpendicular to the common axis CA (see Figure 13 ), or may extend outward at an angle relative to the common axis CA when viewed from the side (see Figure 19)。In some embodiments, the sleeve member 206 includes a slotted nut end and is provided with a passage 320. The slotted nut end and the sleeve member 206 are configured to clamp the star wheel member 132. For example, the passage 320 can be machined to include a release portion that allows air flow.

[0088] The sleeve member 206 extends from the movable wheel 120 but is as short as possible to limit the leverage on the engine crankshaft. In some embodiments, the piston 302 and the cylinder 304 are single-acting cylinders, while in other embodiments, the cylinder 304 is a double-acting cylinder. In some embodiments discussed below, a passage that vents to the atmosphere when the movable wheel 120 is in certain positions can also be formed. In some embodiments, the passage can be blocked to selectively limit the venting to the atmosphere. Seals 322 can be provided throughout the system to restrict air flow and maintain the pressure along the passage 320 and within the chamber 306. For example, the seal 322 is positioned between the coupling portion 310 and the sleeve member 206. In embodiments where the crown is coupled to the rotary joint housing 316 and / or the coupling portion 310, the seal 322 can be positioned between the two. The seal 322 is positioned between the movable wheel 120 and the cylinder 304.

[0089] Referring further to the chamber 306 as described above, the chamber 306 can be defined between various components. For example, the chamber 306 can be defined by the movable wheel 120, the cylinder 304, the piston 302, and the sleeve member 206. In some embodiments, other components can also or alternatively define a portion of the chamber 306. The piston 302 is formed such that no part of the movable wheel 120 or the cylinder can be located below the piston 302 and the sleeve member 206, or between the two, even in the fully open position (e.g., neutral gear).

[0090] During operation, a pressurized fluid source 400 can supply pressurized fluid (e.g., pressurized gas or liquid) to the chamber 306. As the pressurized fluid is introduced into the chamber 306, a force is exerted on the components that define the chamber 306. Since the actuator 300 includes a fixed piston 302 (e.g., fixed together with the sleeve member 206) and a movable cylinder 304 (e.g., moves with the movable wheel 120), when sufficient pressure is introduced to generate a force sufficient to actuate the system, the cylinder 304 and the movable wheel 120 move. The pressure and force applied can be adjusted for a particular function, such as restricting or slowing the outward movement of the movable wheel 120 during acceleration, or actively moving the movable wheel 120 inward. Thus, in operation, the actuator 300 works in conjunction with or is used to adjust typical systems in the CVT 100, which can be calibrated for discrete CVT ratios (e.g., springs, weights, etc.).

[0091] See Figure 19, in some embodiments, the passage 320 is shown to be not in fluid communication with the chamber 306 in the zero gear position. Thus, an accidental application of fluid pressure will not cause the CVT to engage. The fluid will instead travel through the passage 320 and flow through non-airtight components such as the movable wheel bushing 340 to the atmosphere. When the driver depresses the throttle, the shift weight will engage the belt and move the movable wheel inward, such that the passage 320 is positioned to be in fluid communication with the chamber 306. In some embodiments, the tolerance around the movable wheel bushing 340 can be used as a passive bleed port to allow pressurized fluid to escape when the drive clutch 110 is in the zero gear position. This limits the ability of the actuator 300 to shift the drive clutch from the zero gear position (see Figure 14 ) to the engaged position (see Figure 15 ). This can help reduce the undesired engagement of the CVT 100 outside of the calibration settings (such as springs, weights, etc.) of the CVT 100. The passive bleed port 340 is configured such that when the drive clutch 110 is in the zero gear position, the passage 320 is fluidly coupled to the passive bleed port 340 and not fluidly coupled to the chamber 306 (see Figure 19 ). The seal 322 is positioned such that the seal is between the passive bleed port 340 and the chamber 306. Thus, when the drive clutch 110 is in the zero gear position, the passage 320 is fluidly separated from the chamber 306 by the seal 322 and is in fluid communication with the passive bleed port 340, and when the drive clutch is shifted to engage the rubber belt 116, the passage 320 is separated from the passive bleed port 340 and is in fluid communication with the chamber 306. In these embodiments, pressurized air can be applied such that if the actuator 300 engages when the drive clutch 110 is in the zero gear position, the air from the actuator 300 is vented to the atmosphere.

[0092] In those embodiments that do not provide a bleed port, the actuator 300 can be implemented to assist in shifting the drive clutch 110 from the zero gear to engaging the rubber belt 116. Such an embodiment is shown in at least Figures 14 to 17 . In this embodiment, pressurized air or pressurized liquid can be used.

[0093] See Figure 8 , Figure 9 and Figure 20 , in some embodiments, the actuator 300 can include a fluid line 402 that couples a pressurized fluid source 400 and the actuator 300. The actuator 300 can be positioned within the profile of the rubber belt 116, and the pressurized fluid source 400 can be positioned within the profile of the rubber belt 116 or extend through the profile of the rubber belt 116 such that the rubber belt 116 can be removed without removing the fluid line 402 or the actuator 300.

[0094] See Figure 22, in some embodiments, the actuator 300 may include an electromagnetic actuator 500. The electromagnetic actuator 500 may operate using a coil 502 and a solenoid 504 to apply a force to the movable pulley 120.

[0095] Turning to the discussion of the operation of the CVT 100 and the actuator 300 in the vehicle 2, the vehicle 2 includes the previously discussed system that includes a frame 10, a ground member 4, and a powertrain assembly 70, and the powertrain assembly 70 includes the CVT 100 as discussed herein with respect to the actuator 300. Referring to Figure 20 , the vehicle 2 further includes a pressurized fluid source 400 that is coupled to the actuator 300 via a fluid line 402. The pressurized fluid source may be a separate system, such as a compressor, or may be integrated in other systems, or may provide additional functions such as for accessories (e.g., for filling tires). The vehicle also includes a controller 379 that is operatively coupled to at least one of the pressurized fluid source 400 and the actuator 300. The controller 370 is capable of operating to effect actuation of the actuator 300 based on predetermined conditions, user input, or a combination thereof. For example, if certain conditions such as rotational combustion and belt slip are detected, the controller 370 may send instructions to actuate the actuator 300. This may be detected by sensors (not shown) or based on the relationship between wheel speed, engine speed, torque, force, ground speed, power, and throttle position (or other conditions).

[0096] In some embodiments, user input may result in actuation of the actuator 300. For example, the driving configuration may be configured such that the controller 370 is capable of operating to provide various instructions to the actuator 300 and / or the pressurized fluid source 400 based on the selected driving configuration. Non-limiting driving configurations include a standard mode, a comfort mode, and a sport mode. Various instructions may be provided based on the driving configuration and conditions sensed by the vehicle 2. As a non-limiting example, in embodiments implementing pressurized fluid, the vehicle 2 may include a pressure map for each driving mode for indicating the amount of pressure applied via the actuator 300 under various conditions. Figure 24 The standard mode is shown, in which various pressures (Z-axis) are applied based on wheel speed (X-axis) and throttle or accelerator pedal position (Y-axis). In the standard mode, pressure is applied under certain conditions where a specific CVT ratio may not be required for response and acceleration. For example, when the user is significantly maintaining the vehicle speed, greater pressure may be applied to maintain engine speed and lower noise, while in high-acceleration scenarios such as when the throttle is fully open, less pressure or no pressure may be applied. In the comfort mode (see Figure 25 ), greater pressure is applied via the actuator 300 in more scenarios to generally limit acceleration and reduce vehicle noise. In the sport mode (see Figure 23), with little pressure applied, thus allowing the CVT 100 to operate without input or with minimal input from the actuator 300. Various modes can be provided as profiles executed by the controller 370 or instructions provided by the controller 370.

[0097] Go to Figure 26 , in some embodiments, the change in pressure applied by the actuator 300 can be rate-limited. By limiting the rate based on at least one predetermined condition (such as wheel speed, throttle position, etc.), the rider experience can be changed. For example, in the case of low speed or low throttle input, the rate of change of the pressure change is lower to limit sudden changes in the CVT ratio. At low speeds, sudden changes in the CVT ratio may cause the rider to feel less smooth, so the rate limit can make the rider feel smoother. It should be understood that other factors can also be applied when determining the allowable pressure change rate, including torque, force, speed (such as engine, wheel or vehicle speed), brake state, brake pressure and vehicle state (such as in the air).

[0098] In some embodiments, the actuator 300, the pressurized fluid source 400 and / or the valve block (not shown) can be provided with various features to facilitate the implementation of an atmospheric discharge function for control safety in the event of a system-related failure. Similar to the discussion regarding Figure 19 , the actuator 300 can have an atmospheric discharge function, thus allowing the CVT 100 to maintain its typical or manual function provided by the mechanical components of the CVT 100 in the event of a failure of the actuator 300.

[0099] Now refer to Figures 27 to 28 , an alternative continuously variable transmission (CVT) 600 is shown in the figure. The CVT 600 can be similar to the CVT 100. The CVT 600 includes an inner housing 622, an outer housing 624 and a plate member 602 coupled to the inner housing 622. The plate member 602 defines a central portion 604 and an extension member 606 that extends outwardly from the central portion 604 towards the outer housing 624. The extension member 606 defines an orifice 608 that is positioned along the axial extent of the extension member 606. In some embodiments, the extension member 606 is integrally formed with the plate member 602. The CVT 600 includes a driving clutch 610, a driven clutch 612 and a bearing 615 ( Figure 29 ). In some embodiments, an annular member (not shown) can rotate around the bearing 615. The driving clutch 610 is rotatably coupled to a prime mover (not shown, such as an engine, a motor or other prime mover) and is operable to rotate by the prime mover.

[0100] The drive clutch 610 includes a stationary wheel 614 and a movable wheel 616, and the stationary wheel 614 and the movable wheel 616 are respectively supported by an input shaft 630( Figure 29 ). In some embodiments, the movable wheel 616 is operable to translate relative to the stationary wheel 614 along the input shaft 630 to change the spacing between the wheels 614, 616 and to change the input-output ratio of the CVT 600. In some embodiments, the input shaft 630 includes an external thread 704a that is positioned at an axial extent of the input shaft 630.

[0101] Still referring to Figures 27 to 28 , the actuator assembly 650 is operatively coupled to the drive clutch 610. In an embodiment, the actuator assembly 650 is operatively coupled to the movable wheel 616 of the drive clutch 610. A fluid conduit 618 is operatively coupled between the extension member 606 and the actuator assembly 650. That is, the fluid conduit 618 is fluid-coupled to an orifice 608 on the extension member 606 and the actuator assembly 650. The fluid conduit 618 is operatively coupled to a pressurized fluid source (such as the pressurized fluid source 400) to supply fluid (such as air, water, other types of fluids) to the actuator assembly 650. That is, the fluid conduit 618 can operate substantially similarly to the fluid line 402 and supply fluid from the pressurized fluid source (such as the pressurized fluid source 400) to the actuator assembly 650.

[0102] Now referring to Figure 28 , the housing 624 defines a recess 626, and the fluid conduit 618 is configured to be positioned within the recess 626. In some embodiments, the entire fluid conduit 618 is positioned within the recess 626. In some embodiments, only a portion of the fluid conduit 618 is positioned within the recess 626. In some embodiments, the recess 626 may include one or more retaining features (not shown) to retain the fluid conduit 618 within the recess 626.

[0103] Still referring to Figures 27 to 28 , the drive clutch 610 of the CVT 600 includes a star assembly 632 that is operable to facilitate movement of the movable wheel 616. The star assembly 632 includes a base 634 coupled to the movable wheel 616, a cover 636 coupled to the base 634, and a star wheel 638 removably engaged with the base 634. A biasing member (such as a spring 640) is coupled between the cover 636 and the star wheel 638. The star assembly 632 includes a plurality of weights (such as Figure 11 the weight 136 therein). The movable wheel 616 translates along the input shaft 630 using the star assembly 632 to change the CVT ratio of the CVT 600.

[0104] Now referring to Figures 29 to 31, the actuator assembly 650 includes a cylinder 652 (e.g., similar to cylinder 304) coupled to the shroud 636. The actuator assembly 650 includes a rotary joint 654 positioned within the cylinder 652. The rotary joint 654 includes an input nozzle 656 that defines a passage 658 and a coupling portion 670. A crown 698 is coupled between the rotary joint 654 and the cylinder 652. That is, the crown 698 is sized and shaped to be disposed within the cylinder 652, and the crown 698 and the rotary joint 654 cooperate with each other to be sealingly coupled to the cylinder 652. At least one seal or gasket 700 is coupled between the crown 698 and the cylinder 652.

[0105] Now refer to Figure 35 , the coupling portion 670 extends along axis X1 and is generally cylindrical. The coupling portion 670 defines a first body portion 671 and a second body portion 673, and the second body portion 673 is axially offset from the first body portion 671. In some embodiments, the second body portion 673 is a threaded portion. A chamfered portion 675 is axially positioned between the first body portion 679 and the second body portion 673. In some embodiments, the chamfered portion 675 includes a pair of apertures 683. The coupling portion 670 includes an axial face 679 that defines a cavity 681. The cavity 681 includes a first cylindrical portion 672 and a first groove 674, and the first groove 674 is positioned adjacent to the first cylindrical portion 672. A recess 677 is axially offset from the first cylindrical portion 672. A first recess 676a extends through each of the first cylindrical portion 672 and the first groove 674, and a second recess 676b is axially adjacent to the first recess 676a. In some embodiments, the cavity 681 defines angled-offset and matching pairs of recesses 676a, 676b. That is, as Figure 35 shown, the cavity 681 defines two diametrically opposed recesses 676a, 676b. The cavity 681 also defines a recess 678 positioned along axis X1, and the cavity 681 defines a pair of apertures 680. In some embodiments, a pair of passages 682 extend between each pair of apertures 680, 683, respectively. That is, the passages 682 provide an exit from the cavity 681 from the recess 678.

[0106] Again refer to Figures 29 to 31 , a bearing 684 is disposed within the first cylindrical portion 672 and is positioned between the first cylindrical portion 672 of the coupling portion 670 and the passage 658, and the bearing 684 allows the coupling portion 670 to rotate about the input nozzle 656. A washer 686 (e.g., a C-clip) is disposed within the first groove 674 and restricts the bearing 684 from leaving the cavity 681. In some embodiments, a sleeve member 702 is rotatably coupled to the coupling portion 670. Refer to Figure 34, the sleeve member 702 includes a generally cylindrical body 706 that defines a slot 708. In some embodiments, the slot 708 is a generally arcuate slot within the body 706 having an arcuate profile. The body 706 includes a plurality of extensions 710 that extend axially outward from the body 706. A plurality of recesses 712 are positioned between the plurality of extensions 710 to define a plurality of apertures. The sleeve member 702 is hollow and includes a first set of internal threads 709 and a second set of internal threads 704b( Figure 29 ). Referring again to Figure 29 , the sleeve member 702 is fixedly coupled to the coupling portion 670 by the first set of internal threads 709 that threadedly engage the second body portion 673, and the sleeve member 702 is fixedly coupled to the input shaft 630 by the second set of internal threads 704b that mate with the threads 704a of the input shaft 630.

[0107] Referring again to Figures 29 to 31 , the bearing 642 is positioned radially between the housing 636 of the star assembly 632 and the sleeve member 702, and the seal 644 is positioned axially adjacent to the bearing 642. The housing 636 can rotate about the sleeve member 702 over the bearing 642. The bearing 642 can include a channel 642a that extends axially along the bearing 642. The bearing 642 can include a plurality of channels 642a. In some embodiments, the bearing 642 is rotatably fixed to the sleeve member 702 and the channel 642a is radially aligned with the slot 708 in the sleeve member 702.

[0108] Now referring to Figure 32 , the recess 677 of the coupling portion 670 defines a first portion 677a and a second portion 677b. The portions 677a, 677b are defined by a varying height (e.g., within the cavity 681, the diameter of the first portion 677a is greater than the diameter of the second portion 677b). The seal member 688 includes a first extension portion 690 and a second extension portion 692 that is separated from the first extension portion 690. A circular seal 694 is positioned between the first extension portion 690 and the second extension portion 692. The first extension portion 690 is sized and shaped to contact the first portion 677a, and the second extension portion 692 is sized and shaped to contact the second portion 677b. The seal 688 includes a pair of sealing lips 696 that extend downward and contact the input nozzle 656. A retaining washer 697 is positioned axially adjacent to the seal 688 and ensures that the seal 688 maintains a relatively consistent position. The multi-dimensional profile of the seal 688 (e.g., the varying height of the first extension portion 690 and the second extension portion 692) ensures that the seal 688 is properly installed within the recess 677 of the cavity 681.

[0109] Referring again to Figures 29 to 31, the actuator assembly 650 cooperates with the star assembly 632 to actuate the movable wheel 616 of the drive clutch 610. In some embodiments, a chamber 720 is defined between the crown 698 and the cover 636. By filling the chamber 720 with pressurized air using the actuator assembly 650, the actuator assembly 650 pushes the cover 636 of the star assembly 632 and the cylinder 652 of the actuator assembly 650 towards the movable wheel 616 of the drive clutch 610. Since the cover 636 is coupled to the base 634, the movable wheel 616 translates together with the cover 636 of the star assembly 632. The actuator assembly 650 can directly control the spacing between the movable wheel 616 and the stationary wheel 614 of the drive clutch 610. The star assembly 632 can also control the spacing of the drive clutch 610 based on the centrifugal force applied when the input shaft 630 rotates.

[0110] Still referring to Figures 29 to 31 , the CVT 600 remains unactuated until the input shaft 630 reaches a predetermined engagement speed (e.g., a predetermined engine speed (RPM)). Once the CVT 600 reaches the engagement speed, the centrifugal force applied to the drive clutch 610 exceeds the force required to move the counterweight (e.g., the counterweight 136) and compress the biasing member 640, causing the counterweight to rotate and the movable wheel 616 to translate, thereby changing the CVT ratio of the CVT 600 (e.g., the CVT 600 operates similarly to the CVT 100). The movable wheel 616 translates towards the stationary wheel 614, thereby increasing the effective rotational diameter of the drive clutch 610 and changing the CVT ratio of the CVT 600.

[0111] As the movable wheel 616 translates towards the stationary wheel 614 under the action of the centrifugal force of the star assembly 632, the cover 636 of the star assembly 632 moves along the sleeve member 702 together with the movable wheel 616. In the unactuated position, the movable wheel 616 is in the first position ( Figures 29 to 3 0), and the seal 644 is axially positioned along the sleeve member 702 aligned with the slot 708 such that fluid (e.g., air) can move around the seal 644 through the slot 708. In the actuated position or the second position, the cover 636 of the star assembly 632 and the seal 644 translate along the sleeve member 702 such that the seal 644 is axially positioned along the sleeve member 702, thereby preventing fluid (e.g., air) from moving around the seal 644 through the slot 708 (e.g., being blocked). That is, in the first actuated position, air can flow into the slot 708, but may not be able to flow out of the slot 708 because it is blocked by the seal 644.

[0112] Now referring to Figures 30A to 30B and Figure 33, a fluid (such as air) can flow through conduit 618 and into passage 658 in input nozzle 656. The fluid will flow through passage 658, through rotary joint 654 and into recess 678. The fluid (such as air) will be forced through orifice 680, passage 682, and out of orifice 683. The fluid is forced out of orifice 683 on chamfered portion 675 and through recess 712 defined by sleeve member 702. The fluid (such as air) is forced through recess 712 and into chamber 720. The drive clutch 610 is in an unactuated position, such as a first position, and the fluid (such as air) can flow out of chamber 720, through slot 708 around bearing 642 and seal 644 to the ambient atmosphere. That is, when the drive clutch 610 is in the unactuated position (such as when the prime mover is not rotating), since the fluid (such as air) escapes through passage 642a in bearing 642 and slot 708, pressure cannot build up in chamber 720. The position of slot 708 helps prevent actuator assembly 650 from acting on movable pulley 616 when the prime mover is not operating. That is, slot 708 acts similar to a relief valve. Once the drive clutch 610 is in the actuated position, such as a second position, since seal 644 blocks slot 708, the fluid (such as air) is blocked from flowing to the ambient atmosphere, and thus pressure can build up in chamber 720.

[0113] Now refer to Figure 31 , air is forced into chamber 720, the pressure in chamber 720 increases, and a force is applied on cover 636 such that movable pulley 616 translates along input shaft 630. The pressure generated in chamber 720 can vary to change the position of movable pulley 616, thereby controlling the effective diameter of drive clutch 610 and the CVT ratio of CVT 600. That is, as the pressure in chamber 720 increases, movable pulley 616 translates toward stationary pulley 614.

[0114] Now refer to Figure 32, the seal 688 is adapted to prevent air from flowing into or out of the recess 678 near the input nozzle 656. In some embodiments, a third recess 676c is formed between the bearing 684 and the seal 688. An air path is formed between the third recess 676c and the ambient atmosphere to prevent pressure from accumulating in the third recess 676c. The air path is defined by each of the first recess 676a and the second recess 676b such that air can flow between the gasket 686 and the bearing 684 and through the first recess 676a and the second recess 676b. This air path prevents or reduces the likelihood of an increase in pressure within the third recess 676c, thereby helping to maintain the life or usability of each of the bearing 684 and the seal 688. An increase in pressure within the third recess 676c may apply an increased and unnecessary pressure on each of the bearing 684 and the seal 688, thereby reducing the effectiveness of the surrounding components or shortening their life.

[0115] Now referring to Figure 36 , the input nozzle 656 is sized and shaped to fit within the rotary joint 654. The C - clip 686 is also sized and shaped to fit around the input nozzle 656 and is seated within the groove 674 in the coupling portion 670.

[0116] The invention of the present application has been generally described above with respect to specific embodiments. It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments without departing from the scope of the disclosure. Accordingly, these embodiments are intended to cover modifications and variations of the invention as long as these modifications and variations fall within the scope of the appended claims and their equivalents.

Claims

1. A continuously variable transmission, comprising: A driven clutch; A driving clutch, the driving clutch being operatively coupled to the driven clutch, the driving clutch including a stationary wheel, a movable wheel, and a load member, the movable wheel being positioned adjacent to the stationary wheel along a common axis defined by a shaft and being operable to axially translate relative to the stationary wheel; A belt, the belt extending between the driving clutch and the driven clutch; And An actuator, the actuator being coupled to the movable wheel of the driving clutch, the actuator being operable to apply a force to the movable wheel in a direction substantially along or parallel to the common axis.

2. The continuously variable transmission according to claim 1, wherein, The actuator is one of a pneumatic actuator, a hydraulic actuator, and an electromagnetic actuator.

3. The continuously variable transmission according to claim 1, wherein, The actuator is coupled to the shaft.

4. The continuously variable transmission according to claim 3 further includes a star nut, wherein, The actuator includes a piston operatively coupled to the star nut and a cylinder coupled to the movable wheel.

5. The continuously variable transmission according to claim 4, wherein, A chamber is defined between the piston and the movable wheel.

6. The continuously variable transmission according to claim 5, wherein, The piston is fixedly positioned relative to the shaft, and the cylinder is axially movable relative to the shaft.

7. The continuously variable transmission according to claim 6, wherein, The actuator includes a nozzle fluidly coupled to the chamber.

8. The continuously variable transmission according to claim 7, wherein, The nozzle is coupled to the piston, and wherein the piston and the star nut define a passage such that the nozzle is fluidly coupled to the chamber via the passage.

9. A vehicle, comprising: A frame, the frame defining an operator area; A plurality of ground members, the plurality of ground members being configured to support the frame; A powertrain assembly, the powertrain assembly being supported by the frame, the powertrain assembly including: An engine, the engine being operatively coupled to at least one of the plurality of ground members; and A continuously variable transmission driven by the engine, the continuously variable transmission including: A driven clutch; A driving clutch, the driving clutch being operatively coupled to the driven clutch, the driving clutch including a stationary wheel, a movable wheel, and a load member, the movable wheel being positioned adjacent to the stationary wheel along a common axis defined by a shaft and being operable to axially translate relative to the stationary wheel; A belt, the belt extending between the driving clutch and the driven clutch; and An actuator, the actuator being coupled to the movable wheel of the driving clutch, the actuator being operable to apply a force to the movable wheel in a direction substantially along or parallel to the common axis.

10. The vehicle according to claim 9, wherein, The continuously variable transmission includes: A star nut, coupled to the shaft; The piston of the actuator, the piston being coupled to the star nut, wherein the piston is fixedly positioned relative to the shaft; The cylinder of the actuator, the cylinder being coupled to the movable wheel, wherein the cylinder is axially movable relative to the shaft, and wherein a chamber is defined between the piston and the movable wheel by the cylinder; and A nozzle of the actuator, the nozzle being coupled to the piston and fluidly coupled to the chamber.

11. The vehicle according to claim 10, further comprising a pressurized fluid source coupled to the actuator.

12. The vehicle according to claim 11 further includes a controller operatively coupled to at least one of the pressurized fluid source and the actuator, the controller being operable to cause the actuator to actuate based on a predetermined condition.

13. The vehicle according to claim 12, wherein, The predetermined condition includes at least one of the speed of the ground engaging member and the throttle position.

14. The vehicle according to claim 12, wherein, The controller includes at least a first driving configuration and a second driving configuration, wherein the controller causes the actuator to apply a first force to the movable wheel based on a first predetermined condition when in the first driving configuration and to apply a second force to the movable wheel based on the first predetermined condition when in the second driving configuration, wherein the first force is different from the second force.

15. The vehicle according to claim 12, wherein, The controller is configured to limit a rate of change of the force applied by the actuator based on at least one of the speed of the ground engaging member and the throttle position.

16. The vehicle according to claim 11, wherein, The pressurized fluid source includes one of air and hydraulic oil.

17. The vehicle according to claim 11, further comprising a fluid line coupling the pressurized fluid source and the actuator, wherein, The actuator is positioned within the profile of the belt and the pressurized fluid source is positioned within the profile of the belt or extends through the profile of the belt such that the belt can be removed without removing the fluid line or the actuator.

18. The vehicle according to claim 10, wherein, At least one of the piston and the star nut defines a passage such that when the drive clutch shifts to engage the belt, the nozzle is fluidly coupled to the chamber via the passage, and wherein the passage is positioned to vent to the atmosphere when the drive clutch is in the zero gear position.

19. The vehicle according to claim 9, wherein, The continuously variable transmission includes: a star nut coupled to the shaft; a piston of the actuator, the piston being coupled to the star nut, wherein the piston is fixedly positioned relative to the shaft; a cylinder of the actuator, the cylinder being coupled to the movable wheel, wherein the cylinder is axially movable relative to the shaft, and wherein a chamber is defined only between the piston and the cylinder; and a nozzle of the actuator, the nozzle being coupled to the piston and fluidly coupled to the chamber.

20. The vehicle according to claim 18, wherein, The actuator is a removable cartridge such that the actuator and the pressurized fluid source do not require bleeding upon reinstallation.

Images