Axle assembly with a barrel cam

Abstract

An axle assembly including a barrel cam. The barrel cam can be rotatable about a barrel cam axis and can be operatively connected to a first shift collar. Rotation of the barrel cam about the barrel cam axis can control movement of the first shift collar along a first axis.

Description

Technical Field

[0001] The present invention relates to an axle assembly having a cylindrical cam that controls the movement of at least one shift collar. Background

[0002] A driveline assembly having a shift mechanism including a sector cam is disclosed in U.S. Patent No. 10,900,564.

[0003] Summary

[0004] In at least one embodiment, an axle assembly is provided. The axle assembly can include a first shaft, a first gear set, a second gear set, a first shift collar, and a cylindrical cam. The first shaft can be rotatable about a first axis. The first gear set can be rotatable about the first axis. The second gear set can be rotatable about a second axis. Each member of the second gear set can mesh with a different member of the first gear set. The first shift collar can be rotatable about the first axis with the first shaft and can be movable relative to the first shaft along the first axis to selectively couple a member of the first gear set to the first shaft. The cylindrical cam can be operatively connected to the first shift collar and can be rotatable about a cylindrical cam axis. The cylindrical cam axis can be disposed generally parallel to the first axis. Rotation of the cylindrical cam about the cylindrical cam axis can control movement of the first shift collar along the first axis.

[0005] In at least one embodiment, an axle assembly is provided. The axle assembly can include a first shaft, a first gear set, a second gear set, a first shift collar, a second shift collar, and a cylindrical cam. The first shaft can be rotatable about a first axis. The first gear set can be rotatable about the first axis. The second gear set can be rotatable about a second axis. Each member of the second gear set can mesh with a different member of the first gear set. The first shift collar can be rotatable about the first axis with the first shaft and can be movable relative to the first shaft along the first axis to selectively couple a member of the first gear set to the first shaft. The second shift collar can be rotatable about the second axis with the second shaft and can be movable relative to the second shaft along the second axis to selectively couple a member of the second gear set to the second shaft. The cylindrical cam can be rotatable about a cylindrical cam axis that can be disposed generally parallel to the first axis. The cylindrical cam can be operatively connected to the first shift collar and connected to the second shift collar. Rotation of the cylindrical cam about the cylindrical cam axis can control movement of the first shift collar along the first axis and can control movement of the second shift collar along the second axis. Brief Description of the Drawings

[0006] Figure 1 is a schematic illustration of an example of an axle assembly.

[0007] Figure 2 Is a perspective view of an example of a transmission and a shift mechanism that can be provided together with an axle assembly.

[0008] Figure 3 Is a perspective view of a part of a transmission associated with a first shaft.

[0009] Figure 4 Is a sectional view taken along section line 4-4.

[0010] Figure 5 Is a perspective view of a part of a transmission associated with a second shaft.

[0011] Figure 6 Is a sectional view taken along section line 6-6.

[0012] Figure 7 Is a perspective view of the shift mechanism.

[0013] Figure 8 Is a side view showing the shift mechanism in a low-speed position.

[0014] Figure 9 Is a side view showing the shift mechanism in a medium-speed position.

[0015] Figure 10 Is a side view showing the shift mechanism in a high-speed position.

[0016] Figure 11 Is a side view showing the shift mechanism in a neutral position.

[0017] Figure 12 Shows an example of grooves that can be provided with a barrel cam of the shift mechanism. Detailed Description

[0018] As required, detailed embodiments of the present invention are disclosed herein; however, it should be understood that the disclosed embodiments are merely examples of the present invention that can be implemented in various forms and alternative forms. The drawings are not necessarily to scale; some features may be exaggerated or reduced to a minimum to show details of specific components. Therefore, the specific structural and functional details disclosed herein should not be construed as limiting, but rather as a representative basis for teaching those skilled in the art to employ the present invention in various ways.

[0019] Reference Figure 1 , shows an example of an axle assembly 10. The axle assembly 10 can be provided for a vehicle, such as a truck, a bus, a farm equipment, a mining equipment, a military transport or an armed vehicle, or a cargo loading equipment for a land, air, or marine vessel. In one or more embodiments, the vehicle can include a trailer for transporting goods.

[0020] The axle assembly 10 can provide torque to one or more traction wheel assemblies, and the one or more traction wheel assemblies can include tires 12 mounted on wheels 14. The wheels 14 can be mounted to a wheel hub, and the wheel hub can be rotatable about a wheel axis 16.

[0021] The axle assembly 10 can include a torque source 20 or can be operatively connected to the torque source. The torque source 20 can be of any suitable type. For example, the torque source 20 can be a non - electric torque source, an electric torque source, or a combination thereof. An example of a non - electric torque source is an internal combustion engine. An example of an electric torque source is an electric motor 22. The electric motor 22 can include a stator 24 and a rotor 26 that can be rotatable about an axis. A power source 28 (such as a battery, a capacitor, a generator, etc.) can be electrically connected to the electric motor 22 in a manner known to those skilled in the art.

[0022] In at least one configuration, the axle assembly 10 can include a differential assembly 30, at least one half - shaft 32, and a transmission 34. The axle assembly 10 can also include a shift mechanism 36 as Figure 2 shown.

[0023] Referring Figure 1 , the differential assembly 30 can transfer torque to the vehicle traction wheel assemblies and allow the traction wheel assemblies to rotate at different speeds. Additionally, the differential assembly 30 can be operatively connected to the half - shafts 32 and can allow the half - shafts 32 to rotate at different rotational speeds in a manner known to those skilled in the art. For example, the differential assembly 30 can be rotatable about a differential axis 40 and can transfer torque to the half - shafts 32 and the wheels. In one or more configurations, the differential axis 40 can be arranged coaxially with the wheel axis 16. In at least one configuration, the differential assembly 30 can have a ring gear 42, and the ring gear can have teeth that mate or engage with the teeth of a gear portion 44 of a drive pinion 46, and the drive pinion can be associated with the transmission 34. Accordingly, the differential assembly 30 can receive torque from the drive pinion 46 via the ring gear 42 and transfer the torque to the half - shafts 32.

[0024] The half - shafts 32 can transfer torque between the differential assembly 30 and the traction wheel assemblies. Two half - shafts 32 can be provided, and these half - shafts can extend from the differential assembly 30 in opposite directions. Each half - shaft 32 can have a first end and a second end. The first end can be operatively connected to the differential assembly 30. The second end can be arranged opposite the first end and can be operatively connected to the wheel. The half - shafts 32 or portions thereof can extend along an axis (such as the differential axis 40) and can be rotatable about that axis.

[0025] The transmission 34 can transfer torque between the torque source 20 and the differential assembly 30. The torque transfer can be bidirectional. In at least one configuration such as Figure 3 and Figure 4 shown, the transmission 34 can include a first shaft 50, a first gear set 52, and a first shift collar 54. As Figure 5 and Figure 6 best shown, the transmission 34 can also include a second shaft 60, a second gear set 62, and a second shift collar 64.

[0026] Primarily referring to Figure 3 and Figure 4 , the first shaft 50 can be rotatable about a first axis 70. As Figure 1 shown, the first axis 70 can be generally perpendicular to the differential axis 40. The term “generally perpendicular” is used herein to denote features (such as axes) that are perpendicular or very nearly perpendicular to each other, and includes features that are perpendicular to each other within ±2°. For example, the first shaft 50 can be rotatably supported by one or more bearings (such as a first bearing 72 and a second bearing 74). The first bearing 72 and the second bearing 74 can have any suitable configuration. For example, the first bearing 72 and the second bearing 74 can be configured as a roller bearing assembly that can surround the first shaft 50. In at least one configuration, the first shaft 50 can be part of or rotatable with the drive pinion 46.

[0027] The first gear set 52 can include a plurality of gears that can be rotatable about the first axis 70. In the illustrated configuration, the first gear set 52 includes a first drive gear 80, a second drive gear 82, and a third drive gear 84; however, it should be understood that more or fewer gears can be provided. When the gears are coupled to the first shaft 50, the components of the first gear set 52 can rotate with the first shaft 50 about the first axis 70. Conversely, the first shaft 50 can be rotatable about the first axis 70 relative to the components of the first gear set 52 that are decoupled from or not coupled to the first shaft. The components of the first gear set 52 can be selectively coupled to the first shaft 50 by the first shift collar 54, as will be discussed in more detail below.

[0028] The first drive gear 80 can receive the first shaft 50. For example, the first drive gear 80 can have a through hole through which the first shaft 50 can extend. The first drive gear 80 can extend around the first axis 70 and the first shaft 50 and can have a plurality of teeth that can be arranged around the first axis 70 and can face away from the first axis. The teeth of the first drive gear 80 can contact and can cooperate or engage with the teeth of the first gear of the second gear set 62, as will be discussed in more detail below. In at least one configuration, the first drive gear 80 can be fixedly coupled to the first shaft 50 such that the first drive gear 80 can rotate with the first shaft 50 around the first axis 70 and such that the first drive gear 80 does not rotate around the first axis 70 relative to the first shaft 50. In at least one configuration, the first drive gear 80 can be axially positioned along the first axis 70 between the gear portion 44 and the second drive gear 82. For example, the first drive gear 80 can be axially positioned between the first bearing 72 and the spacer 86.

[0029] The second drive gear 82 can receive the first shaft 50. For example, the second drive gear 82 can have a through hole through which the first shaft 50 can extend. The second drive gear 82 can extend around the first axis 70 and the first shaft 50 and can have a plurality of teeth that can be arranged around the first axis 70 and can face away from the first axis. The teeth of the second drive gear 82 can contact and can cooperate or engage with the teeth of the second gear of the second gear set 62, as will be discussed in more detail below. In at least one configuration, the second drive gear 82 can be fixedly coupled to the first shaft 50 such that the second drive gear 82 can rotate with the first shaft 50 around the first axis 70 and such that the second drive gear 82 does not rotate around the first axis 70 relative to the first shaft 50. In at least one configuration, the second drive gear 82 can be axially positioned along the first axis 70 between the first drive gear 80 and the third drive gear 84. Additionally, the second drive gear 82 can be axially positioned closer to the third drive gear 84 than to the first drive gear 80. For example, the spacer 86 can be positioned between the first drive gear 80 and the second drive gear 82 to separate the first drive gear 80 and the second drive gear 82 or to increase the axial distance therebetween, thereby providing alignment with the corresponding members of the second gear set 62, which can be arranged to accommodate the second shift collar 64, as will be discussed in more detail below. Additionally, the second drive gear 82 can have a different diameter than the first drive gear 80. For example, the second drive gear 82 can have a larger diameter than the first drive gear 80.

[0030] The third drive gear 84 can receive the first shaft 50. For example, the third drive gear 84 can have a through-hole, and the first shaft 50 can extend through the through-hole. The third drive gear 84 can extend around the first axis 70 and the first shaft 50, and can have a plurality of teeth that can be arranged around the first axis 70 and can face away from the first axis. The teeth of the third drive gear 84 can contact and cooperate or mesh with the teeth of the third gear of the second gear set 62, as will be discussed in more detail below. The third drive gear 84 can be rotatably arranged on the first shaft 50. A bearing or bushing 88 can be received in the hole of the third drive gear 84 to rotatably support the third drive gear 84 on the first shaft 50. The bushing 88 can also have a flange that can extend away from the first axis 70 and can help separate the third drive gear 84 from the second drive gear 82.

[0031] As Figure 4 best shown in, the third drive gear 84 can include clutch engagement teeth 90 that can be engaged by the first shift collar 54 to selectively couple the third drive gear 84 to the first shaft 50, as will be discussed in more detail below. The clutch engagement teeth 90 can have any suitable configuration. In the illustrated configuration, the clutch engagement teeth 90 are configured as spline gears or spline teeth, where the teeth can be arranged around the first axis 70 and can extend radially away from and away from the first axis 70. Alternatively or additionally, the clutch engagement teeth 90 can be configured as face gears, where the teeth can be arranged around the first axis 70 and can extend axially from one side of the third drive gear 84 toward the first shift collar 54. The third drive gear 84 can be axially positioned between the second drive gear 82 and the first shift collar 54 along the first axis 70. Additionally, the third drive gear 84 can have a different diameter than the first drive gear 80 and the second drive gear 82. For example, the third drive gear 84 can have a larger diameter than the second drive gear 82.

[0032] The first shift collar 54 can be axially positioned between the third drive gear 84 and the second bearing 74. The first shift collar 54 can receive the first shaft 50 and can rotate with the first shaft 50 around the first axis 70. Additionally, the first shift collar 54 can be movable relative to the first shaft 50 along the first axis 70 to selectively couple or connect the components of the first gear set 52 to the first shaft 50. For example, the first shift collar 54 can selectively couple the third drive gear 84 to the first shaft 50, as Figure 4 shown in the shading and as will be discussed in more detail below. In at least one configuration and as Figure 7 best shown in, the first shift collar 54 can include a first shift collar hole 100 and a first shift collar spline 102.

[0033] The first shift collar bore 100 may extend along a first axis 70. The first shift collar bore 100 may be a through bore through which the first shaft 50 may extend.

[0034] The first shift collar spline 102 may operatively connect the first shift collar 54 to the first shaft 50. The first shift collar spline 102 may be disposed within the first shift collar bore 100 and may include spline teeth that may extend toward the first axis 70. The spline teeth may engage or mate with corresponding spline teeth on the first shaft 50 or disposed on an intermediate member that may be fixedly mounted to the first shaft 50, such as Figure 4 the first collar 110 best shown in. For example, the first collar 110 may have spline teeth 112 that may extend away from the first axis 70 and may engage the teeth of the first shift collar spline 102. The first collar 110 may at least partially surround the first shaft 50 and may axially extend between the second bearing 74 and the third drive gear 84 and / or its bushing 88.

[0035] The first shift collar spline 102 may selectively engage the third drive gear 84 to permit or inhibit rotation of the third drive gear 84 relative to the first shaft 50. When the first shift collar 54 is disengaged from the third drive gear 84, the third drive gear 84 may be rotatable relative to the first shaft 50 about the first axis 70. For example, when the first shift collar spline 102 does not cooperate or engage with the clutch engagement teeth 90 of the third drive gear 84 and thus the first shift collar 54 does not connect the third drive gear 84 to the first shaft 50, the third drive gear 84 may be rotatable relative to the first shaft 50. When the first shift collar 54 connects the third drive gear 84 to the first shaft 50, such as when the first shift collar spline 102 cooperates or engages with the clutch engagement teeth 90 of the third drive gear 84, the third drive gear 84 may be rotatable with the first shaft 50 about the first axis 70. It is also contemplated that the first shift collar 54 may be provided with a face gear that may cooperate or engage with the clutch engagement teeth 90 of the third drive gear 84, which third drive gear may also be configured as a face gear. In such a configuration, the first shift collar spline 102 cannot cooperate or engage with the clutch engagement teeth 90.

[0036] Main reference Figure 5 and Figure 6, the second shaft 60 can be spaced apart from the first shaft 50 and can be rotatable about a second axis 120. The second axis 120 can be arranged substantially parallel to the first axis 70. The term "substantially parallel" is used herein to denote features (such as axes) that are parallel or very nearly parallel to each other, and includes features that are parallel to each other within ±2°. The second shaft 60 can be rotatably supported by one or more bearings (such as a first bearing 122 and a second bearing 124). The first bearing 122 and the second bearing 124 can have any suitable configuration. For example, the first bearing 122 and the second bearing 124 can be configured as a roller bearing assembly that can surround the second shaft 60. The second shaft 60 can be operatively connected to the torque source 20. For example, torque can be transmitted from the torque source 20 to the second shaft 60, and then the torque can be transmitted from the second shaft 60 to the first shaft 50 via a gear. In a configuration having a power source, the second shaft 60 can be operatively connected to the rotor 26, such as by directly connecting the rotor shaft to the second shaft 60 or by using a connecting gear set 126, an example of which is shown best in Figure 1 . For example, the connecting gear set 126 can have a first connecting gear that can rotate with the rotor 26 and meshes with a second connecting gear that can rotate with the second shaft 60. In at least one configuration, the transmission 34 can be positioned on a side of the differential assembly 30 opposite to the torque source 20.

[0037] Referring again to Figure 5 and Figure 6 , the second gear set 62 can include a plurality of gears that can rotate about the second axis 120. Each member of the second gear set 62 can mesh with a different member of the first gear set 52. In the illustrated configuration, the second gear set 62 includes a first gear 130, a second gear 132, and a third gear 134; however, it should be understood that more or fewer gears can be provided. When the gears are coupled to the second shaft 60, the members of the second gear set 62 can rotate with the second shaft 60 about the second axis 120. Conversely, the second shaft 60 can be rotatable about the second axis 120 relative to the members of the second gear set 62 that are decoupled or not coupled to the second shaft 60. The members of the second gear set 62 can be selectively coupled to the second shaft 60 by a second shift collar 64, as will be discussed in more detail below.

[0038] The first gear 130 may receive the second shaft 60. For example, the first gear 130 may have a through hole through which the second shaft 60 may extend. The first gear 130 may extend around the second axis 120 and the second shaft 60 and may have a plurality of teeth that may be arranged around the second axis 120 and may face away from the second axis. The teeth of the first gear 130 may contact and may cooperate or mesh with the teeth of the first drive gear 80 of the first gear set 52. In at least one configuration, the first gear 130 may be rotatably disposed on the second shaft 60. A bearing or bushing 140 may be received in the bore of the first gear 130 and may rotatably support the first gear 130 on the second shaft 60.

[0039] As Figure 6 best shown in, the first gear 130 may include clutch engagement teeth 150 that may be engaged by the second shift collar 64 to selectively couple the first gear 130 to the second shaft 60, as will be discussed in more detail below. The clutch engagement teeth 150 may have any suitable configuration. In the illustrated configuration, the clutch engagement teeth 150 are configured as spline gears or spline teeth, where the teeth may be arranged around the second axis 120 and may face away from the second axis 120 and extend radially away from the second axis. Alternatively or additionally, the clutch engagement teeth 150 may be configured as face gears, where the teeth may be arranged around the second axis 120 and may extend axially from one side of the first gear 130 toward the second shift collar 64. The first gear 130 may be axially positioned along the second axis 120 between the first bearing 122 and the second gear 132.

[0040] The second gear 132 may receive the second shaft 60. For example, the second gear 132 may have a through hole through which the second shaft 60 may extend. The second gear 132 may extend around the second axis 120 and the second shaft 60 and may have a plurality of teeth that may be arranged around the second axis 120 and may face away from the second axis. The teeth of the second gear 132 may contact and may cooperate or mesh with the teeth of the second drive gear 82 of the first gear set 52. In at least one configuration, the second gear 132 may be rotatably disposed on the second shaft 60. A bearing or bushing 140 may be received in the bore of the second gear 132 and may rotatably support the second gear 132 on the second shaft 60.

[0041] In at least one configuration, the second gear 132 can include a second clutch engaging tooth 160 that can be engaged by the second shift collar 64 to selectively couple the second gear 132 to the second shaft 60, as will be discussed in more detail below. The second clutch engaging tooth 160 can have any suitable configuration. In the illustrated configuration, the second clutch engaging tooth 160 is configured as a spline gear or spline tooth, wherein the teeth can be arranged around the second axis 120 and can be radially extended away from the second axis 120 and away from the second axis. Alternatively or in addition, the second clutch engaging tooth 160 can be configured as a face gear, wherein the teeth can be arranged around the second axis 120 and can be axially extended from one side of the second gear 132 toward the second shift collar 64. The second gear 132 can be axially positioned between the first gear 130 and the third gear 134 along the second axis 120. For example, the second gear 132 can be axially positioned between the second shift collar 64 and the third gear 134. In addition, the second gear 132 may be axially positioned closer to the third gear 134 than to the first gear 130. For example, a spacer 170 may be positioned between the first gear 130 and the second gear 132 to separate the first gear 130 and the second gear 132 or increase the axial distance therebetween, thereby providing sufficient space for moving the second shift collar 64, as will be discussed in more detail below. The spacer 170 may be integrally formed with the second shaft 60 or may be provided as a separate component that may extend from the second shaft 60. In addition, the second gear 132 may have a different diameter than the first gear 130. For example, the second gear 132 may have a smaller diameter than the first gear 130.

[0042] The third gear 134 can receive the second shaft 60. For example, the third gear 134 can have a through hole through which the second shaft 60 can extend. The third gear 134 can extend around the second axis 120 and the second shaft 60 and can have a plurality of teeth that can be arranged around the second axis 120 and can face away from the second axis. The teeth of the third gear 134 can contact and can cooperate or mesh with the teeth of the third drive gear 84 of the first gear set 52, as will be discussed in more detail below. In at least one configuration, the third gear 134 can be fixedly coupled to the second shaft 60 so that the third gear 134 can rotate with the second shaft 60 around the second axis 120, and so that the third gear 134 does not rotate relative to the second shaft 60 around the second axis 120. In at least one configuration, the third gear 134 can be axially positioned between the second bearing 124 and the second drive gear 82 along the second axis 120. In addition, the third gear 134 can have a different diameter than the first gear 130 and the second gear 132. For example, the third gear 134 may have a smaller diameter than the second gear 132 .

[0043] The second shift collar 64 can be axially positioned between the first gear 130 and the second gear 132. The second shift collar 64 can receive the second shaft 60 and can be rotatable about the second axis 120 with the second shaft 60. In addition, the second shift collar 64 can be movable relative to the second shaft 60 along the second axis 120 so that the components of the second gear set 62 can be selectively coupled or connected to the second shaft 60. For example, the second shift collar 64 can selectively couple the first gear 130 or the second gear 132 to the second shaft 60, as will be discussed in more detail below. In Figure 6 the intermediate portion shown in shadow above, the second shift collar 64 can also decouple the first gear 130 and the second gear 132 from the second shaft 60. In at least one configuration and as Figure 7 best shown in, the second shift collar 64 can include a second shift collar bore 180 and a second shift collar spline 182.

[0044] The second shift collar bore 180 can extend along the second axis 120. The second shift collar bore 180 can be a through hole through which the second shaft 60 can extend.

[0045] The second shift collar spline 182 can operatively connect the second shift collar 64 to the second shaft 60. The second shift collar spline 182 can be disposed in the second shift collar bore 180 and can include spline teeth that can extend toward the second axis 120. The spline teeth can engage or mate with corresponding spline teeth on the second shaft 60 or an intermediate member that can be fixedly mounted to the second shaft 60.

[0046] The second shift collar spline 182 can selectively engage the first gear 130 or the second gear 132 to allow or inhibit rotation of the first gear 130 or the second gear 132 relative to the second shaft 60. For example, the second shift collar spline 182 can mate or engage with the clutch engagement teeth 150 of the first gear 130 to rotatably couple the first gear 130 to the second shaft 60, as Figure 6 shown by the solid line at position A in. When the second shift collar 64 is disengaged from the first gear 130 or does not connect the first gear 130 to the second shaft 60, the first gear 130 can be rotatable about the second axis 120 relative to the second shaft 60. For example, when the second shift collar spline 182 does not mate or engage with the clutch engagement teeth 150 of the first gear 130, the first gear 130 can be rotatable about the second axis 120 relative to the second shaft 60.

[0047] When in the intermediate position shown hatched at position B, the second shift collar spline 182 cannot mate or engage with the clutch engagement teeth 150 of the first gear 130 and the second clutch engagement teeth 160 of the second gear 132, thereby allowing the second shaft 60 to rotate relative to the first gear 130 and the second gear 132.

[0048] When the second shift collar 64 is moved to the right from the Figure 6 viewpoint shown to position C, the second shift collar spline 182 can mate or engage with the second clutch engagement teeth 160 of the second gear 132 to rotatably couple the second gear 132 to the second shaft 60. When the second shift collar 64 is disengaged from the second gear 132 or does not connect the second gear 132 to the second shaft 60, the second gear 132 can be rotatable about the second axis 120 relative to the second shaft 60. For example, when the second shift collar spline 182 does not mate or engage with the second clutch engagement teeth 160 of the second gear 132, the second gear 132 can be rotatable about the second axis 120 relative to the second shaft 60.

[0049] It is also contemplated that the second shift collar 64 can be provided with face gears that can mate or engage with the clutch engagement teeth 150 of the first gear 130, which can also be configured as a face gear; face gears can be provided that can mate or engage with the second clutch engagement teeth 160 of the second gear 132, which can be configured as a face gear; or a combination thereof.

[0050] Primarily referring to Figure 7 and Figure 8 , the shift mechanism 36 can control the positioning of shift collars such as the first shift collar 54 and the second shift collar 64. In at least one configuration, the shift mechanism 36 can include a shift rail 200, a first shift fork 202, a second shift fork 204, a barrel cam 206, or a combination thereof.

[0051] The shift rail 200 can extend along a shift rail axis 210. The shift rail axis 210 can be arranged generally parallel to the first axis 70, the second axis 120, or both. The shift rail 200 can be fixedly positioned such that the shift rail 200 cannot move along the shift rail axis 210 or rotate about the shift rail axis. The shift rail 200 can be spaced from the barrel cam 206 and can support the first shift fork 202 and the second shift fork 204.

[0052] Referring to Figure 3 and Figure 7, the first shift fork 202 can operatively connect the first shift collar 54 to the barrel cam 206. The first shift fork 202 can be slidable relative to the shift guide rail 200 along the shift guide rail axis 210. In at least one configuration, the first shift fork 202 can include a tubular portion 220, a fork arm 222, and a guiding feature 224.

[0053] The tubular portion 220 can receive the shift guide rail 200. In at least one configuration, the tubular portion 220 can have a first end 230, a second end 232, and a shift fork hole 234.

[0054] The first end 230 can face the second shift fork 204.

[0055] The second end 232 can be arranged to be opposite to the first end 230. Thus, the second end 232 can face away from the second shift fork 204.

[0056] The shift fork hole 234 can extend from the first end 230 to the second end 232. The shift guide rail 200 can extend through the shift fork hole 234.

[0057] The fork arm 222 can extend from the tubular portion 220 to the first shift collar 54. The fork arm 222 can have any suitable configuration. For example, the fork arm 222 can have a pair of forks that can be received in the groove of the first shift collar 54 and can allow the first shift collar 54 to rotate relative to the forks about the first axis 70. The fork arm 222 can be arranged close to the second end 232 of the tubular portion 220.

[0058] The guiding feature 224 can operatively connect the first shift fork 202 to the barrel cam 206. The guiding feature 224 can extend from the tubular portion 220 in a direction extending away from the shift fork hole 234 and the shift guide rail axis 210. In at least one configuration, the guiding feature 224 can extend along a guiding feature axis 240, which can be arranged substantially perpendicular to the shift guide rail axis 210, the barrel cam axis of the barrel cam 206, or both. The guiding feature 224 can be arranged close to the first end 230 of the tubular portion 220.

[0059] Refer to Figure 5 and Figure 7, the second shift fork 204 can be spaced apart from the first shift fork 202. The second shift fork 204 can operatively connect the second shift collar 64 to the barrel cam 206. The second shift fork 204 can have a configuration similar to that of the first shift fork 202. The second shift fork 204 can be slidable relative to the shift guide rail 200 along the shift guide rail axis 210. In at least one configuration, the second shift fork 204 can include a tubular portion 220', a fork arm 222', and a guiding feature 224'.

[0060] The tubular portion 220' can receive the shift guide rail 200. In at least one configuration, the tubular portion 220' can have a first end 230', a second end 232', and a shift fork hole 234'.

[0061] The first end 230' can face away from the first shift fork 202.

[0062] The second end 232' can be arranged opposite to the first end 230'. Thus, the second end 232' can face the first shift fork 202.

[0063] The shift fork hole 234' can extend from the first end 230' to the second end 232'. The shift guide rail 200 can extend through the shift fork hole 234'.

[0064] The fork arm 222' can extend from the tubular portion 220' of the second shift fork 204 to the second shift collar 64. The fork arm 222' can have any suitable configuration. For example, the fork arm 222' can have a pair of forks that can be received in the grooves of the second shift collar 64 and can allow the second shift collar 64 to rotate relative to the forks about the second axis 120. The fork arm 222' can be arranged close to the second end 232' of the tubular portion 220.

[0065] The guiding feature 224' can operatively connect the second shift fork 204 to the barrel cam 206. The guiding feature 224' can extend from the tubular portion 220' in a direction away from the shift fork hole 234' and the shift guide rail axis 210. In at least one configuration, the guiding feature 224' can extend along a guiding feature axis 240', which can be arranged substantially perpendicular to the shift guide rail axis 210, the barrel cam axis of the barrel cam 206, or both. The guiding feature 224' can be arranged close to the first end 230' of the tubular portion 222'.

[0066] Main reference Figure 2 and Figure 7, the barrel cam 206 can be operatively connected to the first shift collar 54, the second shift collar 64, or both. The barrel cam 206 can be spaced apart from the transmission 34 and the shift rail 200. In at least one configuration, the barrel cam 206 can have a generally cylindrical configuration.

[0067] The barrel cam 206 can be rotatable about a barrel cam axis 250. For example, the barrel cam 206 can be rotatably supported by a first barrel cam bearing 252 and a second barrel cam bearing 254. The first barrel cam bearing 252 and the second barrel cam bearing 254 can have any suitable configuration. For example, the first barrel cam bearing 252 and the second barrel cam bearing 254 can be configured as a roller bearing assembly that can extend around the barrel cam 206 and can encircle the barrel cam. The first barrel cam bearing 252 and the second barrel cam bearing 254 can be arranged near opposite ends of the barrel cam 206.

[0068] The barrel cam axis 250 can be arranged generally parallel to the first axis 70, the second axis 120, the shift rail axis 210, or a combination thereof. Rotation of the barrel cam 206 about the barrel cam axis 250 can control movement of the first shift collar 54 along the first axis 70, can control movement of the second shift collar 64 along the second axis 120, or both. The shift rail axis 210 can be arranged closer to the first axis 70 than the barrel cam axis 250 is arranged close to the first axis 70. The shift rail axis 210 can be arranged closer to the second axis 120 than the barrel cam axis 250 is arranged close to the second axis 120. In at least one configuration and as Figure 7 best shown in, the barrel cam 206 can have an outer side 260 and a coupling feature 262. The barrel cam 206 can define one or more grooves, such as a first groove 264 and a second groove 266.

[0069] The outer side 260 can face away from the barrel cam axis 250. The outer side 260 or a portion thereof can be cylindrical. A plurality of pawl features 270 can be provided on the outer side 260. The pawl features 270 can be spaced apart from each other and can be positioned to correspond to the rotational position of the barrel cam 206, such as Figures 8 to 11 the position shown. The pawl features 270 can have any suitable configuration. For example, the pawl features 270 can be configured as depressions that can extend toward the barrel cam axis 250. The pawl features 270 can be engaged by a pawl mechanism 272 that Figure 2Best shown in. The pawl feature 270 can help hold the barrel cam 206 in a desired rotational position. As the barrel cam 206 rotates between different rotational positions and their associated pawl features 270 about the barrel cam axis 250, the pawl mechanism 272 can slide along the outer side 260.

[0070] The coupling feature 262 can facilitate the coupling of the barrel cam 206 with an actuator that can rotate the barrel cam 206 about the barrel cam axis 250. In at least one configuration, the coupling feature 262 can extend from an end of the barrel cam 206 and can be arranged along the barrel cam axis 250. The coupling feature 262 can have any suitable configuration. For example, the coupling feature 262 can have a convex configuration, a concave configuration, or a combination thereof. The actuator can have any suitable configuration. For example, the actuator can be an electric actuator, a mechanical actuator, an electromechanical actuator, etc.

[0071] Referring Figure 2 and 7 , the first groove 264 can guide the movement of the first shift fork 202 and thus guide the movement of the first shift collar 54. For example, the first groove 264 can extend from the outer side 260 toward the barrel cam axis 250 and can receive the guiding feature 224 of the first shift fork 202. The guiding feature 224 can extend through the outer side 260 and into the first groove 264. The first groove 264 can be axially positioned between the first barrel cam bearing 252 and the second barrel cam bearing 254. For example, the first groove 264 can be axially positioned between the second barrel cam bearing 254 and the second groove 266.

[0072] The first groove 264 can extend completely around or continuously around the barrel cam axis 250. Thus, the first groove 264 can be a continuous loop or circle without ends. The first groove 264 can have a non-circular configuration that can progress along the barrel cam axis 250 such that as the first groove 264 extends around the barrel cam axis 250, the first groove 264 can become closer to the second groove 266 or can move further away from the second groove 266. In at least one configuration, the first groove 264 can have a first groove side 280 and a second groove side 282, which are referenced Figure 7 and 12 shown.

[0073] The first groove side 280 and the second groove side 282 can extend from the outer side 260 towards the cylindrical cam axis 250. The first groove side 280 and the second groove side 282 can extend continuously around the cylindrical cam axis 250 and can be spaced apart from each other. For example, the first groove side 280 and the second groove side 282 can be mirror images of each other and can be equidistantly spaced apart from each other. In one or more embodiments, the first groove side 280 and the second groove side 282 can be arranged substantially parallel to each other. The first groove side 280 and the second groove side 282 can cooperate to constrain and control the axial movement of the first shift fork 202. For example, the guiding feature 224 of the first shift fork 202 can engage the first groove side 280 to inhibit the movement of the first shift fork 202 towards the first cylindrical cam bearing 252, while the guiding feature 224 can engage the second groove side 282 to inhibit the movement of the first shift fork 202 towards the second cylindrical cam bearing 254.

[0074] Referring to Figure 2 and 7 , the second groove 266 can guide the movement of the second shift fork 204 and thus guide the movement of the second shift collar 64. For example, the second groove 266 can extend from the outer side 260 towards the cylindrical cam axis 250 and can receive the guiding feature 224' of the second shift fork 204. The guiding feature 224' can extend through the outer side 260 and into the second groove 266. The second groove 266 can be axially positioned between the first cylindrical cam bearing 252 and the second cylindrical cam bearing 254. For example, the second groove 266 can be axially positioned between the first cylindrical cam bearing 252 and the first groove 264.

[0075] The second groove 266 can extend completely around or continuously around the cylindrical cam axis 250. Thus, the second groove 266 can be a continuous ring or loop without ends. The second groove 266 can have a non-circular configuration, which can progress along the cylindrical cam axis 250 such that as the second groove 266 extends around the cylindrical cam axis 250, the second groove 266 can become closer to the first groove 264 or can move further away from the first groove 264. However, the second groove 266 can progress differently from the first groove 264. For example, a portion of the first groove 264 can progress away from the second groove 266 at one or more rotational positions. For example, the first groove 264 can progress away from the second groove 266 at one or more rotational positions where the second groove 266 does not progress towards the first groove 264.

[0076] In at least one configuration, the second groove 266 can have a first groove side 280' and a second groove side 282', which are shown with reference to Figure 7 and 12 shown.

[0077] The first groove side 280' and the second groove side 282' can extend from the outer side 260 towards the barrel cam axis 250. The first groove side 280' and the second groove side 282' can extend continuously around the barrel cam axis 250 and can be spaced apart from each other. For example, the first groove side 280' and the second groove side 282' can be mirror images of each other and can be equidistantly spaced apart from each other. In one or more embodiments, the first groove side 280' and the second groove side 282' can be arranged substantially parallel to each other. The first groove side 280' and the second groove side 282' can cooperate to constrain and control the axial movement of the second shift fork 204. For example, the guiding feature 224' of the second shift fork 204 can engage the first groove side 280' to inhibit the movement of the second shift fork 204 towards the first barrel cam bearing 252, while the guiding feature 224' can engage the second groove side 282' to inhibit the movement of the second shift fork 204 towards the second barrel cam bearing 252.

[0078] Reference Figures 8 to 11 Referring now to an example that shows the operation of the shift mechanism 36 and the movement of the first shift collar 54 and the second shift collar 64. The rotation of the barrel cam 206 and the shifting of the shift collars can be in response to an operator command, can be automatic, or a combination thereof. In at least one configuration, a shift can be performed when the rotational speeds of the shift collar and the gear being engaged or disengaged are sufficiently synchronized. By controlling the rotational speed of the first shaft 50, by controlling the rotational speed of the second shaft 60, or a combination thereof, a synchronizer can be used to achieve the sufficient synchronization that allows the shifting or movement of the collar.

[0079] In Figures 8 to 11 an example of the shift collar position is shown. Figure 12 Examples of configurations of the first groove 264 and the second groove 266 that can be associated with these positions are schematically represented therein; however, it should be understood that the shift collar positions can be rearranged or additional shift collar positions can be added, in which case the way the first groove 264 and the second groove 266 ramp relative to each other can be different from the example shown. In Figure 12 the first groove 264 and the second groove 266 are projected into a planar representation, where connector A represents that the first groove 264 is connected and continuous, and connector B represents that the second groove 266 is connected and continuous.

[0080] Referring to Figure 8, the barrel cam 206 is shown in the low-speed position. The first shift collar 54 can couple the third drive gear 84 to the first shaft 50 such that the third drive gear 84 can rotate with the first shaft 50. The second shift collar 64 cannot couple the first gear 130 or the second gear 132 to the second shaft 60. Thus, torque can be transmitted between the first shaft 50 and the second shaft 60 via the third drive gear 84 and the third gear 134.

[0081] Reference Figure 9 , the barrel cam 206 is shown in the medium-speed position. The first shift collar 54 cannot couple the third drive gear 84 to the first shaft 50 and moves to the right from the Figure 8 position shown. The second shift collar 64 moves to the right from the Figure 8 position shown and can couple the second gear 132 to the second shaft 60, but cannot couple the first gear 130 to the second shaft 60. Thus, torque can be transmitted between the first shaft 50 and the second shaft 60 via the second drive gear 82 and the second gear 132.

[0082] Reference Figure 10 , the barrel cam 206 is shown in the high-speed position. The first shift collar 54 is in the same position as in Figure 9 and cannot couple the third drive gear 84 to the first shaft 50. The second shift collar 64 moves to the left from the Figure 8 position shown to couple the first gear 130 to the second shaft 60, but does not couple the second gear 132 to the second shaft 60. Thus, torque can be transmitted between the first shaft 50 and the second shaft 60 via the first drive gear 80 and the first gear 130.

[0083] Refer to Figure 11 , the barrel cam 206 is shown in the neutral position. The first shift collar 54 is in the same position as in Figure 9 and cannot couple the third drive gear 84 to the first shaft 50. The second shift collar 64 is in the same position as in Figure 8 and cannot couple the first gear 130 or the second gear 132 to the second shaft 60. Thus, torque cannot be transmitted between the first shaft 50 and the second shaft 60.

[0084] The axle assembly discussed above can allow the torque source and the transmission to be arranged on opposite sides of the differential assembly. In configurations where the torque source is an electric motor, such a configuration can help thermally isolate the electric motor from heat generated from other components of the axle assembly, such as the transmission and lubricant of the axle assembly, by its fast-rotating rotor bearings (which can rotate at speeds greater than 50,000 rpm). Such thermal isolation can improve the thermal management of the axle assembly and can reduce lubricant heating, which can help increase lubricant life. Additionally, compared to configurations where the electric motor and the transmission extend from the same side of the housing assembly, such an arrangement can provide better weight distribution by positioning the center of mass of the axle assembly closer to the half shafts. As a result, compared to configurations where the electric motor and the transmission extend from the same side of the housing assembly, the "protrusion" or distance of the housing assembly extending from the half shafts can be reduced, and the integrity of the housing structure can be improved. An axle assembly having a barrel cam as described above can allow for a compact shift mechanism, which can help reduce packaging space, weight, associated costs, or a combination thereof. Additionally, the barrel cam can allow the shift collar to be actuated simultaneously or independently and with high accuracy.

[0085] Although the above describes exemplary embodiments, these embodiments are not intended to describe all possible forms of the invention. Rather, the words used in this specification are words of description rather than limitation, and it should be understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of the various implemented embodiments may be combined to form further embodiments of the invention.

Claims

1. An axle assembly, comprising: A first shaft that is rotatable about a first axis; A second shaft that is rotatable about a second axis; A first gear set that is rotatable about the first axis; And A second gear set that is rotatable about the second axis, wherein each member of the second gear set meshes with a different member of the first gear set; A first shift collar that is rotatable with the first shaft about the first axis and is axially movable relative to the first shaft along the first axis to selectively connect a member of the first gear set to the first shaft; A second shift collar that is rotatable with the second shaft about the second axis and is axially movable relative to the second shaft along the second axis to selectively connect a member of the second gear set to the second shaft; And A barrel cam that is rotatable about a barrel cam axis disposed generally parallel to the first axis and is operatively connected to the first shift collar and operatively connected to the second shift collar, wherein rotation of the barrel cam about the barrel cam axis controls movement of the first shift collar along the first axis and controls movement of the second shift collar along the second axis.

2. The axle assembly according to claim 1, wherein, A first shift fork couples the first shift collar to the barrel cam, and the barrel cam defines a first groove that extends completely around the barrel cam axis and receives a guide feature extending from the first shift fork.

3. The axle assembly according to claim 2, wherein, The first groove has a non-circular configuration that tapers along the barrel cam axis.

4. The axle assembly according to claim 2, wherein, The first groove has a first groove side and a second groove side that extend around the barrel cam axis, wherein the guide feature engages the first groove side and the second groove side to constrain axial movement of the first shift fork.

5. The axle assembly according to claim 4, wherein, The first groove side and the second groove side extend from an outer side of the barrel cam facing away from the barrel cam axis toward the barrel cam axis, and the first groove side and the second groove side are disposed generally parallel to each other.

6. The axle assembly according to claim 2, wherein, The first shift fork is slidable along a shift rail that is spaced from the barrel cam and extends generally parallel to the barrel cam axis.

7. The axle assembly according to claim 6, wherein, The barrel cam is rotatably supported by a first barrel cam bearing and a second barrel cam bearing that extend around the barrel cam and are disposed adjacent opposite ends of the barrel cam, wherein the first groove is axially positioned between the first barrel cam bearing and the second barrel cam bearing.

8. The axle assembly according to claim 6, wherein, The shift rail extends along a shift rail axis that is disposed generally parallel to the barrel cam axis, wherein the shift rail axis is disposed closer to the first axis and the second axis than the barrel cam axis is disposed to the first axis and the second axis.

9. The axle assembly according to claim 6, wherein, The first shift fork has a tubular portion having a first end, a second end, and a shift fork hole that extends from the first end to the second end, and the shift guide rail extends through the shift fork hole. Wherein, the first shift fork has a fork arm that extends from the tubular portion to the first shift collar, the guiding feature is arranged adjacent to the first end of the tubular portion, and the fork arm is arranged adjacent to the second end of the tubular portion.

10. The axle assembly according to claim 1, wherein, The first gear set includes a first driving gear, a second driving gear, and a third driving gear. Wherein, the first driving gear and the second driving gear are fixedly coupled to the first shaft, and the third driving gear is rotatably arranged on the first shaft such that when the first shift collar does not connect the third driving gear to the first shaft, the third driving gear can rotate relative to the first shaft about the first axis, and when the first shift collar connects the third driving gear to the first shaft, the third driving gear can rotate with the first shaft.

11. The axle assembly according to claim 10, wherein, The second gear set includes a first gear, a second gear, and a third gear that respectively mesh with the first driving gear, the second driving gear, and the third driving gear. Wherein, the third gear is fixedly coupled to the second shaft, and the first gear and the second gear are rotatably arranged on the second shaft and can be selectively coupled to the second shaft by the second shift collar.

12. The axle assembly according to claim 11, wherein, When the barrel cam is in the low-speed position, the first shift collar connects the third driving gear to the first shaft such that the third driving gear can rotate with the first shaft, and the second shift collar does not connect the first gear or the second gear to the second shaft.

13. The axle assembly according to claim 11, wherein, When the barrel cam is in the medium-speed position, the first shift collar does not connect the third driving gear to the first shaft, and the second shift collar connects the second gear to the second shaft.

14. The axle assembly according to claim 11, wherein, When the barrel cam is in the high-speed position, the first shift collar does not connect the third driving gear to the first shaft, and the second shift collar connects the first gear to the second shaft.

15. The axle assembly according to claim 11, wherein, When the barrel cam is in the neutral position, the first shift collar does not connect the third driving gear to the first shaft, and the second shift collar does not connect the first gear or the second gear to the second shaft.

16. The axle assembly according to claim 11, wherein, The second driving gear is axially positioned on the first shaft between the first driving gear and the third driving gear, and the third driving gear is axially positioned on the first shaft between the second driving gear and the first shift collar.

17. The axle assembly according to claim 16, wherein, The second shift collar is axially positioned between the first gear and the second gear, and the second gear is axially positioned between the second shift collar and the third gear.

18. The axle assembly according to claim 11, wherein, The first shift fork couples the first shift collar to the barrel cam, and the barrel cam defines a first groove that extends completely around the barrel cam axis and receives a first guide feature extending from the first shift fork. A second shift fork connects the second shift collar to the barrel cam, and the barrel cam defines a second groove that extends completely around the barrel cam axis and receives a second guide feature extending from the second shift fork.

19. The axle assembly according to claim 18, wherein, The first groove and the second groove have a non-circular configuration that tapers along the barrel cam axis such that when the second groove does not taper toward the first groove, a portion of the first groove tapers away from the second groove.

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