Differential lubrication

Abstract

A vehicle powertrain can include a differential assembly having a housing partially disposed in a lubricating oil reservoir. The differential assembly translates rotational motion of a pinion gear to a pair of axles extending from the housing and allows for different rotational speeds of the axles. One or more components of the differential assembly (e.g., one or more side gears) can include a plurality of radial recesses configured to distribute lubricant from the lubricating oil reservoir upon rotation of the first side gear.

Description

[0001] introduction

[0002] This disclosure relates to systems and methods for lubricating differentials for vehicles, and more particularly to systems and methods for lubricating open differentials. Summary of the Invention

[0003] This document illustrates an example of a side gear for a differential (e.g., an open differential). In at least some example methods, the differential system includes one or more channels located in a differential housing, configured to draw lubricating oil from a lubricating oil reservoir. The system includes one or more radial grooves on the differential side gear, wherein at least one of the radial grooves includes an inner point where lubricating oil enters the radial groove, and wherein lubricating oil is radially sprayed from the inner point of the radial groove to an outer point. In at least some example methods, the side gear includes a first surface including a set of gears or protrusions configured to engage with a differential gear of the differential. The protrusions may cover a peripheral edge of the first surface. The side gear may also include a second surface arranged to face away from the first surface. The second surface may include a plurality of radial grooves configured to draw lubricating oil in as the side gear rotates.

[0004] In at least some example methods, the differential assembly includes a housing partially disposed within a lubricating oil reservoir, the housing enclosing a plurality of interlocking members configured to convert rotational motion of a pinion into rotational motion of a pair of axles extending from the housing and allowing different rotational speeds of the axles. The plurality of interlocking members may include a pair of differential gears configured to translate rotational motion from the housing to the pair of axles, and at least one side gear driving rotation of a first axle. The side gear may include a first surface and a second surface arranged opposite to the first surface, the first surface including a set of gears or protrusions configured to interlock with the differential gears, wherein the protrusions cover the peripheral edge of the first surface. The second surface may include a plurality of radial grooves configured to draw lubricating oil from the lubricating oil reservoir when the first side gear rotates. Attached Figure Description

[0005] The present disclosure is described in detail with reference to the following accompanying drawings, which illustrate one or more various embodiments. The drawings are provided for illustrative purposes only and show only typical or exemplary embodiments. These drawings are provided to facilitate understanding of the concepts disclosed herein and should not be considered as limitations on the breadth, scope, or applicability of these concepts. It should be noted that these drawings are not necessarily drawn to scale for clarity and ease of explanation. The above and other objects and advantages of the present disclosure will become apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0006] Figure 1A and Figure 1B A pair of examples of differential assemblies with side gears according to some embodiments of the present disclosure are shown, the side gears having grooves for lubricating differential components;

[0007] Figure 2A and Figure 2B A pair of views of an exemplary side gear having multiple grooves according to some embodiments of the present disclosure are shown;

[0008] Figure 3A and Figure 3B A pair of views of an exemplary side gear having multiple angled grooves according to some embodiments of the present disclosure are shown;

[0009] Figure 4 An example of a differential assembly having a pair of separate side gears according to some embodiments of the present disclosure is shown;

[0010] Figure 5 Examples of differential assemblies with pumping mechanisms according to some embodiments of the present disclosure are shown;

[0011] Figure 6 A schematic diagram of an exemplary vehicle system with a differential assembly according to some embodiments of the present disclosure is shown, the differential assembly including side gears configured to improve lubrication within the differential assembly; and

[0012] Figure 7 An exemplary vehicle system with a differential assembly according to some embodiments of the present disclosure is shown, the differential assembly including a side gear configured to improve lubrication within the differential assembly. Detailed Implementation

[0013] The present disclosure is described in detail with reference to the following accompanying drawings, which illustrate one or more various embodiments. The drawings are provided for illustrative purposes only and show only typical or exemplary embodiments. These drawings are provided to facilitate understanding of the concepts disclosed herein and should not be considered as limitations on the breadth, scope, or applicability of these concepts. It should be noted that these drawings are not necessarily drawn to scale for clarity and ease of illustration.

[0014] This article provides methods and systems for lubricating the internal interfaces of differential components.

[0015] Current methods for lubricating differentials employ static oil reservoirs, whereby the rotating parts of the differential pass through the oil based on the available oil level in the reservoir. This method is flawed because the oil is unevenly distributed among the various moving and interlocking parts as the different components of the differential rotate in response to different inputs to the system. Furthermore, the distribution is affected by the static oil level in the reservoir as the components rotate. For example, if the static oil level is below the innermost radial distance of an interlocking gear or the center of a side gear, the oil cannot reach that part of the gear interface, and the components will continue to operate without any lubrication, resulting in additional operating noise and increased wear between components. Alternatively, filling the differential with additional lubricant increases the overall resistance of the differential and reduces powertrain efficiency.

[0016] Other methods rely on forced lubrication to attempt to increase the distribution of lubricating oil between the interfaces of components within the differential. However, these methods also have drawbacks because the addition of a pump or injector mechanism creates packaging problems for the differential components within the vehicle's suspension environment. Furthermore, the pump delivers lubricant to a single location and thus provides only a single track at which lubricant is introduced into the interfaces between the moving parts of the differential, resulting in uneven lubrication of various components. To achieve the same level of consistent operation of differential components without lubrication, additional operating noise can occur, and components may fatigue or fail before their expected lifespan.

[0017] In light of the foregoing, some of the example systems and methods described herein lubricate the differential by assembling channels into the differential housing and multiple recesses into the rotating components of the differential (e.g., one or two side gears). The differential may include a housing with components such as pinions (e.g., side gears fixed to the housing). The housing may contain one or more channels that serve as openings to allow lubricant to be pumped from a static lubricant reservoir to interfaces between the internal components of the differential. As the side gears rotate in an open state, they create a negative pressure at the inner openings of the channels, which draws lubricant from the static reservoir. Within the differential housing, at least one drive shaft, axle, or half-shaft may also be present for translating rotational motion received at the differential from the powertrain to the road wheels. The side gears may be supported within the housing for transmitting rotational motion from the side gears / housing to the axles. The differential gear may be supported on a main shaft supported at either end by the housing.

[0018] Therefore, rotation of the housing causes rotation of the main shaft, whereby the differential gear exerts rotational motion on the side gear. The differential can be an open differential, allowing different rotational speeds of the axle, for example, to accommodate vehicle steering. The side gear includes an interface side and a reverse side that may include a hub, the interface side having a protrusion or gear that mates with the differential gear. The reverse or back side may have a surface in which a plurality of grooves are formed, the grooves being positioned such that they extend from the outer diameter of the side gear to the center of the side gear or adjacent to the center of the side gear. In some example methods, the grooves may have a length sufficient to reach the static lubricant level within the differential. Thus, as the side gear rotates, each groove receives lubricant accumulated at the bottom of the differential housing, where the lubricant is drawn from the static lubricant level into the groove and distributed throughout the junction of the differential assembly. In other example methods, the static lubricant level may be relatively low, where lubricant is pumped or distributed into the grooves in the side gear through channels in the differential. In one example, the channels in the housing may be positioned such that the inner opening of the channel is aligned with the radially outer end of the groove in the side gear. In this example, any pumping of the lubricating oil can cause it to collect at the bottom of the housing for full rotation of the radially outer edge of the side gear. In another example, the channel in the housing can be positioned such that the inner opening of the channel aligns with the radially inner end of the groove in the side gear. In this example, any pumping of the lubricating oil causes it to translate directly from the reservoir through the channel into the groove in the side gear, so that the lubricating oil does not collect in the housing due to pumping, but is readily distributed through the rotation of the side gear.

[0019] As in the previous methods mentioned above, these example techniques advantageously rely not only on a static lubricant level. Instead, the side gear or hub has multiple grooves in its face that are immersed in a static lubricant level, and the rotation of the hub generates a pumping action that draws lubricant into each corresponding groove by centrifugal force, and then distributes the lubricant throughout the differential components by centrifugal force. Channels in the differential housing can serve as a continuous lubricant feed mechanism, as lubricant previously accumulated within the differential housing is distributed between the components. Thus, while a static lubricant level may allow at least a portion of the hub to become at least partially saturated with lubricant, the combination of channels in the differential housing and grooves on the side gear enables greater lubricant distribution throughout the various components of the differential.

[0020] Furthermore, while pumps may be employed in some example methods to further assist in the lubrication of differential components, the example methods presented herein rely not only on external mechanisms such as pumps to improve lubricant distribution throughout the differential housing. Instead, the side gear recesses and / or channels in the differential housing utilize existing components of the differential assembly to improve lubrication. More specifically, the side gear recesses in the various examples below can reach the volume of lubricant in the reservoir, and the structure of the recesses draws lubricant into the recesses and distributes lubricant around the housing of the differential assembly due to the rotation of the side gears, thereby providing more consistent lubrication to the differential assembly components.

[0021] In some embodiments, the radial grooves extend from the diameter of the innermost point near the center of the side gear surface to the outer diameter. In some embodiments, the grooves are arranged along a straight radial line, while in other example methods, one or more grooves in the grooves are angled relative to the radial direction of the side gear. The angle of the grooves may correspond to a target lubrication rate (e.g., 0.15 liters per minute) such that a target volume of lubricant is distributed around the differential housing at the target lubrication rate. The angle typically allows for longer groove lengths, which allows more grooves to enter the lubricant reservoir, thereby distributing a larger volume of lubricant throughout the housing for each passage of the groove and / or rotation of the side gear. Therefore, the geometry of the grooves, the positioning of the grooves, and the rotational speed or speed range of the side gear can each affect the volume of lubricant distributed via the grooves.

[0022] In some embodiments, at least a portion of the side gear is located below the surface of the static lubricant reservoir. Therefore, as the side gear rotates, at least a portion of each groove is immersed below the surface of the static lubricant reservoir. The spacing and number of grooves can be determined such that at least one groove in each groove is immersed in the lubricant reservoir each time to enable continuous distribution of lubricant at the side gear. The spacing and number of grooves can also be determined such that the volume of the grooves matching the rotational speed of the side gear allows the differential assembly to receive lubricant at a flow rate comparable to the target speed.

[0023] In some embodiments, each recess has at least one opening at one end. This opening allows lubricating oil to enter the recess from an oil reservoir, enabling the lubricating oil to be distributed by the rotation of the side gear. The opening also allows lubricating oil to exit the recess, distributing the lubricating oil throughout the differential assembly.

[0024] In some embodiments, each side gear of the differential assembly includes a groove feature similar to or the same as the groove feature of the first side gear, such that the second part of the differential assembly receives improved lubrication.

[0025] In some implementations, at least one pair of channels are located in the lower portion of the differential assembly housing, such that rotation of the side gear draws lubricating oil from a static lubricating oil reservoir.

[0026] In some embodiments, the second channel is located in the upper portion of the differential assembly and includes a pump or other mechanism for forced lubrication through the housing and / or within the differential. The pump may be configured to draw lubricating oil from a static lubricating oil reservoir and discharge lubricating oil from the differential assembly in a vertically upper position, thereby allowing lubricant to be delivered across substantially all mating surfaces within the housing. The combination of the pump and recesses in the side gears further enhances consistent lubricant distribution throughout the differential assembly.

[0027] In some embodiments, the groove is embedded separately from the side gear and positioned adjacent to the hub of the side gear. The hub can be arranged to rotate at the same rate as the side gear.

[0028] Turn now Figure 1A and Figure 1B The diagram illustrates a pair of exemplary differential assemblies 100A and 100B according to some embodiments of the present disclosure, wherein each exemplary differential assembly has a side gear configured to distribute lubricant from a static lubricating oil reservoir. It should be noted that differential assembly 100A, differential assembly 100B, or any component thereof can be integrated into… Figure 2A and Figure 2B The side gear shown Figure 3A and Figure 3B The side gear shown Figure 4 Differential assembly 400, Figure 5 Differential assembly 500, Figure 6 Vehicle system 600 or Figure 7 Of any of the 700 vehicles.

[0029] Differential assemblies 100A and 100B are enclosed by housing 102. Housing 102 provides a housing for multiple interlocking components that are part of differential assemblies 100A and 100B. For example, the interlocking components may include at least one side gear, a set of planetary gears, a pair of axles, and a pinion, wherein the side gear is positioned at the end of the axle. The pinion may be positioned to translate rotational motion from a transmission assembly into the differential assembly. The pinion may interlock with multiple protrusions of the side gear to translate rotational motion to the planetary gears. The planetary gears may be positioned to interlock with rings and gears to translate rotational motion to wheel assemblies attached to the axles.

[0030] Side gear 104 is positioned within housing 102. The edge of side gear 104 is positioned such that, with rotation of the side gear, lubricating oil from a static lubricating oil reservoir is drawn into radial grooves 108, within which housing 102 resides. Radial grooves 108 may be positioned in one or both side gears 104 of differential assemblies 100A, 100B. Radial grooves 108 are structured such that, with rotation of the side gear 104, lubricating oil is drawn into each corresponding groove. Lubrication passages 110 allow lubricating oil to exit from the static lubricating oil reservoir into housing 102, such that each radial groove in radial groove 108 absorbs a portion of the lubricating oil and distributes it through internal components enclosed within housing 102.

[0031] The lubricating oil level can be represented by lubricating oil levels 106A or 106B, depending on the desired performance parameters of each differential assembly in differential assemblies 100A and 100B, respectively. The lubricating oil reservoir 106A is at a depth such that at least a portion of the radial groove 108 is submerged below the surface of the lubricating oil reservoir 106A. This allows the side gear 104 to be continuously submerged in the lubricating oil reservoir 106A, ensuring continuous distribution of lubricating oil within the housing 102. In contrast, the lubricating oil reservoir 106B is at a depth such that the radial groove 108 is not submerged below the surface of the lubricating oil reservoir 106B. In some embodiments, the lubricating oil reservoir 106B may be preferred because a lower lubricating oil level reduces overall friction within the unit. Therefore, due to reduced resistance, the side gear 104 accelerates and rotates freely at a faster rate. As the side gear 104 rotates, lubricating oil from the lubricating oil reservoir 106B is pumped into the recess 108 via lubrication channels 110, each of which has an end submerged below the surface of the lubricating oil reservoir 106B. Rotation of the side gear 104 can create a pressure differential between a first end and a second end of each lubricating channel 110, the first end being open to the internal structure enclosed by the housing 102, and the second end being submerged below the surface of the lubricating oil reservoir 106B. This pressure differential can cause lubricating oil to enter the housing 102 from the lubricating oil reservoir 106B, thereby feeding the lubricating oil into the radial recesses and distributing it throughout the interface of the differential assembly 100B.

[0032] In one example, the lubrication channel 110 can be positioned such that the inner opening of each lubrication channel in the lubrication channel 110 is aligned with the radial outer end of the radial groove 108. In this example, any pumping of lubricating oil can cause the lubricating oil to collect in the bottom of the housing for full rotation of the radial outer edge of the side gear. In another example, the lubrication channel 110 in the housing can be positioned such that the inner opening of each lubrication channel in the lubrication channel 110 is aligned with the radial inner end of the radial groove 108 (e.g., as shown in the image). Figure 1A and Figure 1B (As shown). In this example, any pumping of the lubricating oil causes the lubricating oil to be directly translated from the reservoir through the lubrication channel 110 into the radial groove 108, so that the lubricating oil does not pool in the housing due to pumping, but is easily distributed by the rotation of the side gear.

[0033] Figure 2A and Figure 2B Exemplary side gears 200 according to some embodiments of the present disclosure are shown, each of which has a plurality of recesses. It should be noted that the side gears 200 or any components thereof can be integrated into the differential assembly of FIG1. Figure 3A and Figure 3B Side gears, Figure 4 Differential assembly 400, Figure 5 Differential assembly 500, Figure 6 Vehicle system 600 or Figure 7 Of any of the 700 vehicles.

[0034] like Figure 2A and Figure 2B As shown, the side gear 200 includes a surface 202 arranged facing away from the central portion of the differential assembly (e.g., differential assembly 100 of FIG. 1). The back face of the side gear 200 may include protrusions or gears configured to engage with other gears of the differential. A central opening 204 is an opening through which an axle protrudes to form an interface with other internal rotating components within the differential assembly (e.g., an interface with a star gear). Radial grooves 206 are grooves embedded in the surface 202, and in some examples, are positioned such that as the surface 202 rotates about a central axis, at least a portion of each radial groove 206 reaches below the lubricating oil level 208. Alternatively, as mentioned above, the lubricating oil level may be relatively low. Each radial groove 206 is arranged such that the innermost and outermost radial points are radially aligned without angular offset.

[0035] Side gear 200 Figure 2B The image shown is a perspective view of a side gear with radial grooves 206. Figure 2BAs shown, each radial groove in the radial grooves 206 of the side gear 200 includes a depth below the surface 202, but does not form an opening through the side gear 200. Additionally, each radial groove in the radial grooves 206 has a radially inner end that does not contact the structure defining the central opening 204 (e.g., the hub 207 of the side gear 200). The depth, length, and width of each radial groove can be determined based on factors such as the rotational speed of the side gear 200, the desired lubricating oil level within the differential assembly of the side gear 200, and the number of grooves required to maintain ideal lubricating oil distribution.

[0036] Turn now Figure 3A and Figure 3B An exemplary side gear 300 with multiple angled grooves is shown according to some embodiments of the present disclosure. It should be noted that the side gear 300 or any component thereof can be integrated into the differential assembly of FIG1. Figure 2A and Figure 2B Side gears, Figure 4 Differential assembly 400, Figure 5 Differential assembly 500, Figure 6 Vehicle system 600 or Figure 7 Of any of the 700 vehicles.

[0037] like Figure 3A and Figure 3B As shown, the side gear 300 includes a surface 302 arranged away from the central portion of the differential assembly (e.g., differential assembly 100 of FIG. 1). A central opening 304 is an opening through which an axle with the side gear protrudes to form an interface with other internal rotating components within the differential assembly (e.g., with a star gear). Radial grooves 306 are grooves embedded in the surface 302 and positioned such that as the surface 302 rotates about a central axis, at least a portion of each radial groove in the radial grooves 306 reaches below the lubricating oil level 308. Alternatively, as mentioned above, the lubricating oil level may be relatively low. Each radial groove in the radial grooves 306 is arranged such that the innermost and outermost radial points are not radially aligned. The angle α of each radial groove in the radial grooves 306 relative to the radial direction of the side gear 300 is based on the rotational speed corresponding to when the differential components are disengaged, such that lubricating oil can circulate throughout the differential without translating the rotational motion to the wheel assemblies.

[0038] Angle α also corresponds to an ideal lubrication rate, ensuring that the lubricating oil drawn into the groove assembly can adequately lubricate all interfaces within the differential assembly. In one example, the channel in the housing can be positioned such that the inner opening of the channel is aligned with the radial outer end of the radial groove 306, as... Figure 3AAs shown. In this example, any pumping of lubricating oil can cause the lubricating oil to collect in the bottom of the housing for full rotation of the radial outer edge of the side gear 300. In another example, the channel in the housing can be positioned such that the inner opening of the channel is aligned with the radial inner end of the radial groove 306 of the side gear (e.g., as shown). Figure 1A and Figure 1B (As shown). In this example, any pumping of the lubricating oil causes the lubricating oil to be directly translated from the reservoir through the channel into the radial groove 306 in the side gear, so that the lubricating oil does not pool in the housing due to pumping, but is easily distributed through the rotation of the side gear.

[0039] Side gear 300 Figure 3B The image shown is a perspective view of a side gear with radial grooves 306. Figure 3B As shown, each radial groove in the radial grooves 306 includes a depth below surface 302, but does not form an opening in the material including the side gear 300. Additionally, each radial groove in the radial grooves 306 has a radially inner end that does not contact the structure defining the central opening 304 (e.g., hub 307). The depth, length, and width of each radial groove in the radial grooves can be determined based on factors such as the rotational speed of the side gear 300, the desired lubricating oil level within the differential assembly utilizing the side gear 300, and the number of grooves required to maintain ideal lubricating oil distribution. Furthermore, the angle α can be considered in relation to the length, width, depth, and number of radial grooves 306, because relative to the... Figure 2A and Figure 2B The radial groove 206, the angle α can increase the overall length of the radial groove 306.

[0040] Angle α can also correspond to an ideal lubrication rate, allowing the lubricating oil drawn into the set of recesses to adequately lubricate all interfaces within the differential assembly. For example, a larger value corresponding to angle α will tend to produce a greater lubrication rate for a given rotational speed of side gears 300A and 300B by “pumping” a greater amount of lubricant from below the lubricating oil level 308. More specifically, a larger value corresponding to angle α enables embodiments of recesses 306 that are typically longer than those of recesses aligned radially with surface 302 (e.g., as shown by the recesses of side gears 200A and 200B compared to those of side gears 300A and 300B). Thus, the angled recesses 306 proportionally increase the amount of lubricant volume contained in and / or delivered throughout the differential assembly.

[0041] In some embodiments, angle α is an acute angle (e.g., less than 90 degrees and not perpendicular) and does not exceed a value such that the groove 306 rotates parallel to the outer diameter of the side gears 300A and 300B. If angle α is used to position each groove 306 such that they form circular grooves on the surfaces of the ring gears 300A and 300B, then the edges without grooves 306 are rotated through the lubricating oil surface 308, and lubricating oil is drawn in to distribute around the differential assembly including the side gears 300A and 300B.

[0042] In one example, the channel in the housing can be positioned such that the inner opening of the channel is aligned with the radial outer end of the radial groove 306 (e.g., as shown in the image). Figure 3A (As shown). In this example, any pumping of the lubricating oil can cause it to collect at the bottom of the housing for full rotation of the radial outer edge of the side gear. In another example, the channel in the housing can be positioned such that the inner opening of the channel is aligned with the radial inner end of the radial groove 306. In this example, any pumping of the lubricating oil causes it to translate directly from the reservoir through the channel into the radial groove 306, so that the lubricating oil does not collect in the housing due to pumping, but is readily distributed through the rotation of the side gear.

[0043] In some embodiments, the radial groove 306 is shaped to enhance oil flow to achieve target lubrication and cooling rates. In some embodiments, the radial groove 306 includes a profile with at least one rounded side. Rounded grooves typically prevent sharp angles and can additionally act as stress concentrators. Additionally, rounded grooves can be forged into gears to improve grain flow of material around the groove and improve the strength of the component in which the groove is formed. In some embodiments, specific use cases for the radial groove 306 can determine the optimal groove geometry. For example, use cases driving the groove geometry may include target operating temperature and / or operating temperature range, target operating rotational speed and / or operating rotational speed range, different lubricant or oil viscosities and / or other characteristics related to lubrication flow, and the expected duty cycle of the differential assembly including the radial groove 306. Generally, a larger groove cross-sectional area allows more oil flow for better lubrication and cooling, while limiting flow through a relatively smaller cross-sectional area can improve overall efficiency (i.e., less viscous loss). In some embodiments, the profile of the cross-section of each radial groove in the radial groove 306 may be the same for the entire groove opening. In some implementations, the profile of the cross-section of each radial groove in the radial groove can be varied along the opening of each groove. For example, a reduced cross-section can be used to accelerate the oil flow along the groove, or most of the groove can be excessively large and can be narrowed at the outlet of the radially outer portion to reduce losses due to turbulence or friction.

[0044] Figure 4 An exemplary differential assembly 400 having a pair of separate side gears according to some embodiments of the present disclosure is shown. It should be noted that the differential assembly 400 may include, for example, the differential assembly 100 of FIG1. Figure 2A and Figure 2B Side gear 200 or Figure 3A and Figure 3B Any of the components described above in the side gear 300. The differential assembly 400 or any of its components may also be integrated into... Figure 5 Differential assembly 500, Figure 6 Vehicle system 600 or Figure 7 Of any of the 700 vehicles.

[0045] The differential assembly 400 is enclosed by a housing 402. The housing 402 typically provides a housing for multiple intersecting components that are part of the differential assembly 400. The differential assembly 400 can be configured to direct rotational motion through a small gear (…). Figure 4 (Not shown) The rotational motion is transmitted to a pair of side gears 404, which are driven by an electric motor, transmission, etc. Each side gear 404 drives its corresponding axle 414. The differential assembly 400 generally facilitates the isolation and translation of rotational motion to a pair of wheel assemblies associated with each axle in the axles 414.

[0046] Gear 404 is positioned within housing 402. The edges of gear 404 are positioned such that they rotate through a surface of lubricating oil surface 406, which is formed by a static lubricating oil reservoir residing within housing 402. Radial groove 408 may be positioned in one or both of the side gears 404 (e.g., Figure 4 (As shown). As the side gear 404 rotates within the housing 402, the grooves 408 are drawn through the lubricating oil surface 406. The lubrication channels 410 generally facilitate the delivery of lubricant from the static lubricating oil reservoir into the housing 402, such that each radial groove in the radial grooves 408 absorbs lubricant and distributes it through internal components enclosed within the housing 402. In one example, the channels in the housing may be positioned such that the inner opening of the channel is aligned with the radially outer end of the groove in the side gear. In this example, any pumping of the lubricating oil may cause the lubricating oil to pool in the bottom of the housing for full rotation of the radially outer edge of the side gear. In another example, the channels in the housing may be positioned such that the inner opening of the channel is aligned with the radially inner end of the groove in the side gear. In this example, any pumping of the lubricating oil causes the lubricating oil to translate directly from the reservoir through the channel into the groove in the side gear, such that the lubricating oil does not pool in the housing due to pumping, but is readily distributed through the rotation of the side gear.

[0047] Figure 5An exemplary differential assembly 500 with a pump according to some embodiments of the present disclosure is shown. It should be noted that the differential assembly 500 or any component thereof may be integrated into the differential assembly 100 of FIG1. Figure 2A and Figure 2B Side gear 200, Figure 3A and Figure 3B Side gear 300, Figure 4 Differential assembly 400, Figure 6 Vehicle system 600 or Figure 7 Of any of the 700 vehicles.

[0048] The differential assembly 500 includes a housing 502. The housing 502 provides a enclosure for a plurality of intersecting components that are part of the differential assembly 500. For example, the housing 502 may be fixed for rotation with a pair of side gears driven by at least one pinion, which receives power from an electric motor, transmission, etc. Figure 5 The rotational power (not shown in the diagram). The housing 502 can drive the rotation of a pair of side gears 504, and allows for differential speed of rotation via a differential gear 505 supported on the main shaft 503.

[0049] Side gears 504 are positioned within housing 502. The edges of side gears 504 can each be positioned such that their lower portions rotate through a surface of lubricating oil level 506, which may be a lubricating oil level formed by a static lubricating oil reservoir within housing 502. Radial grooves 508 are positioned on side gears 504 and are drawn through lubricating oil level 506 as side gears 504 rotate within housing 502. Radial grooves 508 can be radially aligned, for example, as described above. Figure 2A and / or Figure 2B In the middle, or it can be at an angle, such as Figure 3A and / or Figure 3B As shown. Lubrication channels 510 facilitate the delivery of lubricant from static lubricant reservoirs 506 to housing 502, such that each radial groove in radial recesses 508 absorbs lubricant and distributes it through internal components enclosed within housing 502 due to the rotation of side gears 504. Each side gear 504 drives its corresponding axle 514. Differential assembly 500 generally facilitates rotational motion to the isolated translation of a pair of wheel assemblies associated with each axle in axles 514.

[0050] The differential assembly 500 can employ a pump to further enhance the distribution of lubricant within the differential assembly 500. For example, an oil distribution line 512 extends below the oil level 506 and delivers lubricant to the pump 516. The pump 516 can be positioned in the upper portion of the housing 502, such as... Figure 5As shown, and therefore can be configured to pump lubricant from reservoir 506 into housing 502 from a raised position. In some embodiments, pump 516 can pump lubricant directly into at least one radial groove in radial groove 508.

[0051] Figure 6 A schematic diagram of an exemplary vehicle system 600 with a differential assembly according to some embodiments of the present disclosure is shown, the differential assembly being configured to improve lubrication within the differential assembly. It should be noted that the vehicle 600 or any component thereof may be integrated into the differential assembly 100 of FIG1. Figure 2A and Figure 2B Side gear 200, Figure 3A and Figure 3B Side gear 300, Figure 4 Differential assembly 400 and Figure 5 In any of the differential components 500.

[0052] Vehicle 602 includes a body 604 and a vehicle powertrain assembly 606. The powertrain assembly 606 may include one or more electric motors, an internal combustion (IC) engine, or any other engine used to provide rotational power to provide prime mover power to vehicle 602. Therefore, vehicle 602 may be a battery electric vehicle (BEV), a hybrid vehicle employing a combination of an electric motor and an internal combustion engine, or a vehicle relying solely on an internal combustion engine for prime mover power. Within the vehicle powertrain assembly 606, there is a static lubricating oil reservoir 608. The static lubricating oil reservoir 608 is a source of lubrication for the differential housing 610 and the interfacing components therein. The differential housing 610 may be rotated by a pinion gear that receives rotational power from an electric motor, engine, transmission, etc. The differential housing 610 may then drive axles 614A and 614B, for example, through one or more differential gears 612 that rotate with the housing 610 and subsequently rotate side gears 616A and / or 616B. Side gears 616A and 616B can be derived from the above description in Figures 1 to 12. Figure 5 Any side gear as described herein. Additionally, in some embodiments, the differential housing 610 intersects with the pump 618. In some embodiments, the pump 618 may correspond to... Figure 5 Pump 516. Pump 618 can represent any type of mechanism that, when connected to differential housing 610, provides additional forced lubrication to components that intersect within differential housing 610.

[0053] Turn now Figure 7An exemplary vehicle system 700 with a differential assembly according to some embodiments of the present disclosure is shown, the differential assembly including side gears configured to improve lubrication within the differential assembly. It should be noted that the vehicle 700 or any component thereof may be integrated into the differential assembly 100 of FIG1. Figure 2A and Figure 2B Side gear 200, Figure 3A and Figure 3B Side gear 300, Figure 4 Differential assembly 400, Figure 5 Differential assembly 500 and Figure 6 In any of the vehicle systems 600.

[0054] Vehicle system 700 includes a vehicle support structure 702. As shown, vehicle support structure 702 is a "slide" structure to which vehicle passenger compartments, cargo areas (not shown), etc., can be mounted. Mounted in vehicle support structure 702 are one or more electric motors 704, a battery pack 706, a suspension 708, and a fan assembly 710. Motors 704 are powered by battery pack 706 and typically provide rotational motion to the wheels via differential 712. Vehicle system 700 may include Figure 6 The components of the vehicle system 600, and Figures 1 to 12. Figure 5 Any other element or combination thereof depicted in the figure. Differential 712 may include the differential assembly 100 of Figure 1. Figure 4 Differential assembly 400 or such Figure 2A , Figure 2B , Figure 3A , Figure 3B , Figure 5 or Figure 6 Elements of any combination of the elements depicted.

[0055] The differential 712 may include a housing 714. The housing 714 provides a enclosure for multiple intersecting components that are part of the differential 712. For example, as discussed above, a side gear fixed for rotation with the housing 714 may be composed of a pinion (…). Figure 7 Driven by a pinion (not shown), the pinion then rotates a main shaft having a pair of differential gears 724. The differential gears then drive the side gears 716 of the differential assembly 712, and allow different rotational speeds for corresponding axles, for example, in the manner described above.

[0056] Side gears 716 may each be positioned within housing 714. The edges of side gears 716 may be positioned such that they rotate through a surface of lubricating oil surface 718, formed by a static lubricating oil reservoir residing within housing 714. Radial grooves 720 may be positioned on one or both side gears 716 and are drawn through lubricating oil surface 718 as the side gears 716 rotate within housing 714. Lubrication channels 722 may also be provided to introduce lubricant from the static lubricating oil reservoir 718 into housing 714, such that each radial groove of radial grooves 720 absorbs lubricant and distributes it throughout the internal components enclosed within housing 714. In some embodiments, radial grooves 720 may be embedded in a hub separate from the side gears 716, the hub being mechanically fixed to the side gears 716 such that the hub rotates together with the side gears 716.

[0057] The systems and processes discussed above are intended to be illustrative and not restrictive. Those skilled in the art will recognize that the actions of the processes discussed herein can be omitted, modified, combined, and / or rearranged, and any additional actions can be performed without departing from the scope of this disclosure. More generally, the above disclosure is intended to be exemplary and not restrictive. Only the appended claims are intended to set the limits regarding the scope of this disclosure. Furthermore, it should be noted that the features and limitations described in any embodiment are applicable to any other embodiment herein, and flowcharts or examples associated with one embodiment can be combined with any other embodiment in a suitable manner, performed in a different order, or in parallel. Moreover, the systems and methods described herein are operable in real time. It should also be noted that the above systems and / or methods can be applied to or used according to other systems and / or methods.

[0058] While some parts of this disclosure may refer to "convention" or examples, any such references are merely for providing context to this disclosure and do not constitute any admission that constitutes prior art.

Claims

1. A differential system, the differential system comprising: One or more channels, located in the differential housing, are configured to draw lubricating oil from a lubricating oil reservoir; and A plurality of radial grooves on the differential side gear, wherein at least one of the radial grooves includes an inner point where the lubricating oil enters the radial groove, and wherein the lubricating oil is radially sprayed from the inner point of the radial groove to an outer point. The one or more channels include a pickup point located radially outside the radial outer edge of the side gear, and the lubricant is drawn from the pickup point to the inner point of the radial groove.

2. The differential system according to claim 1, wherein the pickup point is below the static liquid level of the lubricating oil reservoir.

3. The differential system of claim 1, wherein each of the plurality of radial grooves extends from the inner point to the outer point, the outer point being adjacent to the outer diameter of the side gear, wherein the outer point is radially aligned with the inner point.

4. The differential system of claim 1, wherein each of the plurality of radial grooves extends from the inner point to the outer point, the outer point being adjacent to the outer diameter of the side gear, and wherein the outer point is radially displaced from the inner point such that each of the plurality of radial grooves defines an acute angle relative to a radial direction extending from the center of the side gear.

5. The differential system of claim 1, wherein each of the plurality of radial grooves is positioned such that the rotational movement of the side gear draws lubricating oil from the lubricating oil reservoir into each of the plurality of radial grooves.

6. The differential system of claim 1, wherein each of the plurality of radial grooves is uniformly spaced around the periphery of the side gear, such that for each rotational position of the side gear, at least a portion of one of the radial grooves is immersed in a lubricating oil reservoir.

7. The differential system of claim 1, wherein the differential side gear includes a first face having a gear, the gear being configured to engage a corresponding gear of the differential system, wherein, Each of the plurality of radial grooves is embedded in a second surface of the differential side gear opposite to the first surface, and each of the plurality of radial grooves defines a groove depth relative to the second surface.

8. The differential system of claim 1, wherein each of the plurality of radial grooves has at least one end forming a radial opening for the lubricating oil to enter from the lubricating oil reservoir.

9. The differential system of claim 1, wherein the rotation of the side gear generates a pressure differential, the pressure differential causing lubricating oil to enter the differential housing from the lubricating oil reservoir through the one or more channels.

10. A differential assembly, the differential assembly comprising: A pair of differential gears configured to translate rotational motion to a pair of axles; One or more channels, located in the differential housing, are configured to draw lubricating oil from a lubricating oil reservoir; and A pair of side gears that drive the rotation of each axle in the vehicle axle, wherein each side gear includes a plurality of radial grooves, wherein at least one of the radial grooves includes an inner point where lubricating oil enters the radial groove, and wherein the lubricating oil is radially sprayed from the inner point of the radial groove to an outer point. The one or more channels include a pickup point located radially outside the radial outer edge of the side gear, and the lubricant is drawn from the pickup point to the inner point of the radial groove.

11. The differential assembly of claim 10, wherein the pickup point is below the static fluid level of the lubricating oil reservoir.

12. The differential assembly of claim 10, wherein each of the plurality of radial grooves extends from the inner point to the outer point, the outer point being adjacent to the outer diameter of the side gear, wherein the outer point is radially aligned with the inner point.

13. The differential assembly of claim 10, wherein each of the plurality of radial grooves extends from the inner point to the outer point, the outer point being adjacent to the outer diameter of the side gear, and wherein the outer point is radially displaced from the inner point such that each of the plurality of radial grooves defines an acute angle relative to a radial direction extending from the center point.

14. The differential assembly of claim 10, wherein each of the differential gears includes a first face having a gear, the gears being configured to engage a corresponding gear of the differential assembly, wherein, Each of the plurality of radial grooves is embedded in a second surface of the differential gear opposite to the first surface, and each of the plurality of radial grooves defines a groove depth relative to the second surface.

15. The differential assembly of claim 10, wherein each of the plurality of radial grooves is uniformly spaced such that, for each rotational position of the first side gear, at least a portion of one of the radial grooves is immersed in a lubricating oil reservoir.

16. The differential assembly of claim 10, wherein each of the plurality of radial grooves is embedded in a second face opposite to a first face of the differential gear, the first face defining the gear, the gear being configured to engage a mating gear of the differential assembly such that the volume corresponding to the sum of the spaces formed by the plurality of radial grooves corresponds to a target lubrication rate.

17. The differential assembly of claim 10, wherein each of the plurality of radial grooves has an end forming a radial opening configured to receive lubricant from a lubricating oil reservoir of the differential assembly.

18. The differential assembly of claim 10, further comprising: A pump configured to pump lubricating oil from the lubricating oil reservoir to the top portion of a plurality of interchange components.

19. The differential assembly of claim 10, wherein the differential is an open differential.

20. A differential assembly, the differential assembly comprising: A pair of differential gears configured to translate rotational motion to a pair of axles; One or more channels, located in the differential housing, are configured to draw lubricating oil from a lubricating oil reservoir; A pair of side gears that drive the rotation of each axle in the vehicle axle, wherein each side gear includes a plurality of radial grooves, at least one of the radial grooves including an inner point where lubricating oil enters, and wherein the lubricating oil is radially sprayed from the inner point of the radial groove to an outer point. A pump configured to pump lubricating oil from the lubricating oil reservoir to the upper part of the housing of the differential gear and the side gear.

21. The differential assembly of claim 20, wherein the pump is configured to pump lubricating oil directly into one or more radial recesses.

22. The differential assembly of claim 20, wherein the pump is located in the upper part of the differential housing.

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