Patent Application
20190249748
This disclosure relates to flexible-drive overrunning alternator pulleys.
Vehicle engines, such as internal combustion engines, typically include an alternator that, when driven by a pulley of the vehicle engine, provides electrical power to components of the vehicle. For example, the alternator may provide electrical power to a battery of the vehicle, which may charge the battery. As the vehicle engine operates, a mechanical load may be transferred to the alternator and pulley, which may be referred to as an alternator-pulley system.
Increasingly, modern vehicles require more electrical power to operate various electrical components of the vehicle. This may result in an increased load being placed on components of the vehicle engine, such as the alternator-pulley system. The increased load placed on the alternator-pulley system may increase an inertia generated by the alternator, which may result in wear or damage to the alternator-pulley system.
In order to reduce the impact on an alternator-pulley system caused by the increased load, the alternator-pulley system may include a one-way overrunning alternator pulley that transmits torque from the vehicle engine to the alternator. A one-way overrunning alternator pulley can reduce negative side effects experienced by the alternator-pulley caused by inertia generated by the alternator. However, while the pulley is driving the alternator, the one-way overrunning alternator pulley may generate irregular vibrations that decrease the operating efficiency of the alternator-pulley system and/or create an undesirable experience for an operator of a vehicle associated with the vehicle engine.
Disclosed herein are implementations of flexible-drive overrunning alternator pulleys.
An aspect of the disclosed embodiments is a flexible-drive overrunning alternator pulley for reducing vibration and noise associated with a vehicle engine. The flexible-drive overrunning alternator pulley comprises: a shaft that comprises: a flange disposed at a first end of the shaft; and an axle extending from a first side of the flange to a second end of the shaft, the second end of the shaft being opposed to the first end of the shaft; a shaft sleeve adapted to receive the axle of the shaft; first splines that include one or more teeth being disposed on a first side of the shaft sleeve; a spring adapted to engage the first side of the flange at a first end of the spring and a second side of the shaft sleeve at a second end of the spring, wherein the second side of the shaft sleeve is disposed opposite the first side of the shaft sleeve, wherein the spring is adapted to transmit torque between the shaft sleeve and the flange; a pulley that comprises an inner bore extending from a first side of the pulley to a second side of the pulley; and a bearing adapted to engage the first splines, wherein the bearing transmits torque between the pulley and the shaft sleeve in response to the speed of the pulley being higher than the speed of the shaft sleeve, and wherein the bearing overruns in response to the speed of the pulley being lower than the speed of the shaft sleeve.
Another aspect of the disclosed embodiments is a pulley that comprises: a shaft that comprises: a flange disposed at a first end of the shaft; and an axle extending from a first side of the flange to a second end of the shaft, the second end of the shaft being opposed to the first end of the shaft; a shaft sleeve adapted to receive the axle of the shaft; a spring adapted to engage the first side of the flange at a first end of the spring and a second side of the shaft sleeve at a second end of the spring, wherein the second side of the shaft sleeve is disposed opposite the first side of the shaft sleeve, wherein the spring is adapted to transmit torque between the shaft sleeve and the flange; and a bearing that includes: an inner bore extending through the bearing; an upper portion of the bearing adapted to engage a portion of the shaft sleeve; a middle portion of the bearing that includes a roller, wherein the roller is adapted to engage a portion of the upper portion of the bearing; and a lower portion of the bearing that includes a chamber adapted to receive a portion of the roller of the middle portion.
Another aspect of the disclosed embodiments is a system that comprises: a shaft that comprises: a flange disposed at a first end of the shaft; and an axle extending from a first side of the flange to a second end of the shaft, the second end of the shaft being opposed to the first end of the shaft; a shaft sleeve adapted to receive the axle of the shaft; first splines that include one or more teeth being disposed on a first side of the shaft sleeve; a spring adapted to engage the first side of the flange at a first end of the spring and a second side of the shaft sleeve at a second end of the spring, wherein the second side of the shaft sleeve is disposed opposite the first side of the shaft sleeve, wherein the spring is adapted to transmit torque between the shaft sleeve and the flange; a bearing that includes: an inner bore extending through the bearing; an upper portion of the bearing that includes second splines including one or more teeth being disposed on the inner bore of the bearing, wherein the second splines are adapted to correspond with the first splines being disposed on the shaft sleeve; a middle portion of the bearing that includes a roller, wherein the roller is adapted to engage a portion of the upper portion of the bearing; and a lower portion of the bearing that includes a chamber, wherein the chamber is adapted to receive a portion of the roller of the middle portion; a washer that includes an inner bore adapted to receive a portion of the flange of the shaft; a pulley that includes an inner bore extending through the pulley, wherein the inner bore is adapted to receive the washer and the bearing; and a ball bearing that includes an inner bore that receives a portion of the axle of the shaft, wherein the ball bearing is adapted to be received by the inner bore of the pulley.
Variations in these and other aspects, features, elements, implementations, and embodiments of the methods, apparatus, procedures, and algorithms disclosed herein are described in further detail hereinafter.
The disclosure is best understood from the following detailed description when read in conjunction with the accompanying drawings. It is emphasized that, according to common practice, the various features of the drawings are not to scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity.
A vehicle typically utilizes electrical power in order to control ignition components and/or other electronic components associated with the vehicle. A vehicle engine, such as a spark-ignition internal combustion engine or other suitable engine, includes an alternator-pulley system. As the vehicle engine operates, the vehicle engine drives a belt associated with the alternator-pulley system which drives an alternator of the alternator-pulley system. The alternator provides electrical power to a battery of the vehicle. The electrical power may charge the battery. The battery may be used to supply electrical power ignition components of the vehicle during vehicle startup. The vehicle engine and/or components of the alternator-pulley system may produce undesirable vibration and/or noise while the engine and the alternator-pulley system operate. As the amount of electrical power utilized by a modern vehicle has increased, alternator loads and engine torsional fluctuations have increased proportionally. Accordingly, it may be desirable to utilize an alternator-pulley system that includes higher decoupling capabilities, a higher damping ratio, and greater flexibility than the characteristic of typical alternator-pulley systems, which may reduce vibration and/or noise generated by the alternator-pulley system. This may prolong the life of the alternator-pulley system and/or the vehicle engine, while increasing an efficiency of power transmission from the vehicle engine to the alternator.
In some embodiments according to the principles of the present disclosure, an alternator-pulley system includes a flexible-drive overrunning alternator pulley. A flexible-drive overrunning alternator pulley is adapted to transmit torque from the vehicle engine to the alternator through the flexible-drive overrunning alternator pulley in response to acceleration of the vehicle engine. The flexible-drive overrunning alternator pulley is adapted to decouple the alternator from the pulley when the alternator overruns the pulley (e.g., when an angular velocity of the alternator is higher than an angular velocity of the pulley). As will be described, the flexible-drive overrunning alternator pulley reduces and/or controls vibration and/or noise generated by the vehicle engine and/or the alternator-pulley system. Additionally, or alternatively, the flexible-drive overrunning alternator pulley can reduce and/or control belt jitter, increase power transmission efficiency of a battery charging system associated with the battery, and/or prolong the operating life of components of the alternator-pulley system and/or other components associated with the vehicle engine.
The flexible-drive overrunning alternator pulley assembly 100 includes a shaft 200, a bearing 300, a pulley 400, a washer 430, a bearing 500, a shaft sleeve 600, and a spring 700. As is generally illustrated in
The first spring seat aperture 240 is disposed at the second side 210B of the flange 210. For example, the second side 210B of the flange 210 includes a recess that includes an arcuate or substantially arcuate profile, or other suitable profile. The first spring seat aperture 240 is disposed on an end of the recess.
In some embodiments, the axle 220 includes a first outer portion 270 and a second outer portion 280. The first outer portion 270 includes a cylindrical or substantially cylindrical profile, or other suitable profile. The second outer portion 280 includes a cylindrical or substantially cylindrical profile, or other suitable profile. A diameter associated with the profile of the first outer portion 270 is smaller than a diameter associated with the profile of the second outer portion 280.
The shaft 200 includes one or more splines 250 disposed on the surface of the first inner portion 230A. The splines 250 can be straight-sided splines, involute splines, other suitable splines, or a combination thereof. The shaft 200 includes threads 260 disposed on the surface of the second inner portion 230B. The threads 260 may include helical threads or other suitable threads. The threads 260 may be left-handed threads, right-handed threads, or other suitable threads.
In some embodiments, the shaft 200 may be adapted to cooperatively operate with a portion of the alternator to transmit torque to the alternator. For example, the shaft 200 may engage a portion of the alternator at the threads 260 and/or splines 250. For example, the alternator may include a shaft that includes threads that are adapted to mate or cooperate with the threads 260. The threads associated with the alternator shaft may have the same or similar pitch, hand, and nominal diameter as the threads 260. The alternator shaft may engage (e.g., may be screwed into) the inner bore 230 of the shaft 200.
Additionally, or alternatively, the alternator shaft may include splines that correspond to the splines 250 of the shaft 200. The alternator shaft may be adapted to engage the shaft 200 by mating the splines of the alternator shaft with the splines 250 of the shaft 200. Engagement of the alternator shaft and the shaft 200 can be adjusted by a wrench or another suitable device. As described herein, the diameter of the first inner portion 230A is larger than the diameter associated with the second inner portion 230B. An outer diameter of the alternator shaft may include a diameter that is slightly smaller than the diameter of the first inner portion 230A and slightly larger than the diameter of the second inner portion 230B, such that the alternator shaft cannot pass into or through the inner bore 230.
The flexible-drive overrunning alternator pulley assembly 100 includes a bearing 300, as is generally illustrated in
In some embodiments, the chamber 370 includes an asymmetric wedge-shaped profile or other suitable profile. For example, the profile of the chamber 370 includes two surfaces that are defined by a lower ramp 370B and an upper ramp 370A. The slope of a profile of the lower ramp 370B is steeper than the slope of a profile of the upper ramp 370A. For example, the slope of the profile of the upper ramp 370A may be adapted, such that the rollers 360 ride or traverse a portion of the upper ramp 370A and lock or jam the upper portion 310 and/or the lower portion 330 when the one or more rollers 360 are driven by the chamber 370 in a first direction. The slope of the profile of the lower ramp 370B may be adapted to stop the rollers 360 from riding or traversing a portion of the lower ramp 370B when the rollers 360 are driven by the chamber 370 in a second direction that is opposite to the first direction (e.g., the rollers 360 roll between the upper portion 310 and the lower portion 330).
In some embodiments, the upper portion 310 includes splines 350 that define the inner profile of the upper portion 310. For example, the splines 350 include one or more teeth that include a profile. The profile of the splines 350 may include a square or substantially square profile, a round or substantially round profile, or other suitable profile. In some embodiments, the one or more teeth of the splines 350 are evenly or substantially evenly distributed around the inner profile of the inner bore 340. While only limited examples are described herein, the splines 350 may be implemented in various ways, such as a non-spline key set.
In some embodiments, the flexible-drive overrunning alternator pulley assembly 100 includes a pulley 400, as is generally illustrated in
In some embodiments, the pulley 400 includes a washer 430. The outer profile of the washer 430 is defined by the inner profile of the inner bore 410. The washer 430 is adapted to be received by the inner bore 410. For example, the washer 430 is press-fit into the inner bore 410. The washer 430 may be adapted to slide into the inner bore 410. In some embodiments, the washer 430 includes an inner bore 440 that is adapted to receive a portion of the flange 210. For example, the flange 210 is press-fit into the inner bore 440. The washer 430 is adapted to rotate about the flange 210.
In some embodiments, the flexible-drive overrunning alternator pulley assembly 100 includes a bearing 500, as is generally illustrated in
The flexible-drive overrunning alternator pulley assembly 100 includes a shaft sleeve 600, as is generally illustrated in
The flexible-drive overrunning alternator pulley assembly 100 includes a spring 700, as is generally illustrated in
In some embodiments, the axle 220 of the shaft 200 is inserted through the inner bore 340 of the bearing 300. As described above, the second outer portion 280 of the axle 220 is adapted to engage the inner bore 340 of the upper portion 310 of the bearing 300 and the inner bore 630 of the shaft sleeve 600. The splines 620 are adapted to engage the upper portion 310 of the bearing 300 at the splines 350, such that the one or more teeth of the splines 620 fit snugly within the one or more teeth of the splines 350. In some embodiments, the surface of the first outer portion 270 includes a diameter that is smaller than the diameter of the inner bore 340 of the bearing 300, such that the bearing 300 only engages the axle 220 by the upper portion 310. The bearing 300 is adapted to rotate about the axle 220 of the shaft 200.
In some embodiments, the round edge profile of the lower portion 330 includes a diameter that is larger than a diameter of the round edge profile of the middle portion 320. The diameter of the round edge profile of the lower portion 330 is also larger than a diameter associated with the round edge profile of the upper portion 310. The round edge profile of the lower portion 330 is adapted to correspond with the inner surface of the inner bore 410. For example, the lower portion 330 is press-fit into the inner bore 410, and the upper portion 310 can rotate within the inner bore 410 when the upper portion 310 is not engaged with the lower portion 330.
In some embodiments, the bearing 300 is adapted to transmit torque from the pulley 400 to the shaft sleeve 600 when the pulley 400 runs faster (e.g., when the angular velocity of the pulley 400 is higher than the angular velocity of the shaft sleeve 600) than the shaft sleeve 600. The bearing 300 is adapted to decouple the pulley 400 and the shaft sleeve 600 when the shaft sleeve 600 overruns the pulley 400 (e.g., when an angular velocity of the shaft sleeve 600 is higher than an angular velocity of the pulley 400). For example, the upper portion 310 of the bearing 300 may engage the shaft sleeve 600, and the lower portion 330 of the bearing 300 may engage the inner bore 410 of the pulley 400.
When the load on the pulley 400 increases, the pulley 400 accelerates in a first direction. The lower portion 330 of the bearing 300 accelerates with the pulley 400 in a first direction. When an angular velocity of the lower portion 330 exceeds an angular velocity of the upper portion 310, the rollers 360 ride up the upper ramp 370A and lock and/or jam the upper portion 310 and the lower portion 330 (e.g., the upper portion 310 and the lower portion 330 are engaged through the rollers 360 and are running at the same speed and in the same direction). The bearing 300 transmits torque from the pulley 400 to the shaft sleeve 600 through the engagement of the shaft sleeve 600 and the upper portion 310. The shaft sleeve 600 then acts on the spring 700, which drives the shaft 200 to accelerate in a first direction. While the pulley 400 is driving the shaft 200, the damping characteristic of the spring 700 reduces and/or controls the vibration and noise generated by the vehicle engine and/or the alternator-pulley system, as described herein.
When the load on the pulley 400 decreases, the pulley 400 decelerates in the first direction. The lower portion 330 of the bearing 300 decelerates with the pulley 400 in the first direction. When the angular velocity of the lower portion 330 is lower than the angular velocity of the upper portion 310, the lower ramp 370B stops the rollers 360 from riding up the lower ramp 370B. The rollers 360 roll between the lower ramp 370B and the upper ramp 370A. The middle portion 320 decouples the upper portion 310 and the lower portion 330 (e.g., the upper portion 310 slides on the lower portion 330 through the rolling of the rollers 360).
In some embodiments, an overrunning alternator pulley for reducing vibration and noise associated with a vehicle engine may include: a shaft that comprises: a flange disposed at a first end of the shaft; and an axle extending from a first side of the flange to a second end of the shaft, the second end of the shaft being opposed to the first end of the shaft; a shaft sleeve adapted to receive the axle of the shaft; first splines that include one or more teeth being disposed on a first side of the shaft sleeve; a spring adapted to engage the first side of the flange at a first end of the spring and a second side of the shaft sleeve at a second end of the spring, wherein the second side of the shaft sleeve is disposed opposite the first side of the shaft sleeve, wherein the spring is adapted to transmit torque between the shaft sleeve and the flange; a pulley that comprises an inner bore extending from a first side of the pulley to a second side of the pulley; and a bearing adapted to engage the first splines, wherein the bearing transmits torque between the pulley and the shaft sleeve in response to the speed of the pulley being higher than the speed of the shaft sleeve, and wherein the bearing overruns in response to the speed of the pulley being lower than the speed of the shaft sleeve.
In some embodiments, a pulley may include: a shaft that comprises: a flange disposed at a first end of the shaft; and an axle extending from a first side of the flange to a second end of the shaft, the second end of the shaft being opposed to the first end of the shaft; a shaft sleeve adapted to receive the axle of the shaft; a spring adapted to engage the first side of the flange at a first end of the spring and a second side of the shaft sleeve at a second end of the spring, wherein the second side of the shaft sleeve is disposed opposite the first side of the shaft sleeve, wherein the spring is adapted to transmit torque between the shaft sleeve and the flange; and a bearing includes: an inner bore extending through the bearing; an upper portion of the bearing adapted to engage a portion of the shaft sleeve; a middle portion of the bearing that includes a roller, wherein the roller is adapted to engage a portion of the upper portion of the bearing; and a lower portion of the bearing that includes a chamber adapted to receive a portion of the roller of the middle portion.
In some embodiments, a system for reducing vibration and noise associated with a vehicle engine may include: a flange disposed at a first end of the shaft; and an axle extending from a first side of the flange to a second end of the shaft, the second end of the shaft being opposed to the first end of the shaft; a shaft sleeve adapted to receive the axle of the shaft; first splines that include one or more teeth being disposed on a first side of the shaft sleeve; a spring adapted to engage the first side of the flange at a first end of the spring and a second side of the shaft sleeve at a second end of the spring, wherein the second side of the shaft sleeve is disposed opposite the first side of the shaft sleeve, wherein the spring is adapted to transmit torque between the shaft sleeve and the flange; a bearing including: an inner bore extending through the bearing; an upper portion of the bearing that includes second splines including one or more teeth being disposed on the inner bore of the bearing, wherein the second splines are adapted to correspond with the first splines being disposed on the shaft sleeve; a middle portion of the bearing that includes a roller, wherein the roller is adapted to engage a portion of the upper portion of the bearing; and a lower portion of the bearing that includes a chamber, wherein the chamber is adapted to receive a portion of the roller; a washer that includes an inner bore adapted to receive a portion of the flange of the shaft; a pulley that includes an inner bore extending through the pulley, wherein the inner bore is adapted to receive the washer and the bearing; and a ball bearing that includes an inner bore that receives a portion of the axle, wherein the ball bearing is adapted to be received by the inner bore of the pulley.
As used herein, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or”. That is, unless specified otherwise, or clearly indicated otherwise by the context, “X includes A or B” is intended to indicate any of the natural inclusive permutations thereof. That is, if X includes A; X includes B; or X includes both A and B, then “X includes A or B” is satisfied under any of the foregoing instances. In addition, the articles “a” and “an” as used in this application and the appended claims should generally be construed to mean “one or more” unless specified otherwise or clearly indicated otherwise by the context to be directed to a singular form.
Further, for simplicity of explanation, although the figures and descriptions herein may include components or elements of the system disclosed herein, components or elements of the system disclosed herein may occur in various relative position. Additionally, elements of the system disclosed herein may combine with other elements not explicitly presented and described herein. Furthermore, not all elements of the system described herein may be required to implement a system in accordance with this disclosure. Although aspects, features, and elements are described herein in particular combinations, each aspect, feature, or element may be used independently or in various combinations with or without other aspects, features, and elements.
While the disclosure has been described in connection with certain embodiments or implementations, it is to be understood that the disclosure is not to be limited to the disclosed embodiments or implementations but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims, which scope is to be accorded the broadest interpretation as is permitted under the law so as to encompass all such modifications and equivalent arrangements.
