A driveline yoke assembly may include a yoke and a barrel. The yoke may include first and second arms extending from a base. The base may include a first protrusion extending radially therefrom. The barrel may be axially fixed to the yoke and may define an axially extending body having a second protrusion extending radially therefrom and engaged with the first protrusion to transfer rotation from the barrel to the yoke.

FIELD

The present disclosure relates to vehicle drivelines and more specifically to yoke assemblies of vehicle drivelines.

BACKGROUND

Universal joints are commonly used in drivelines of automobiles and trucks. The universal joint transmits power between two rotating shafts. A typical universal joint includes a pair of opposed yoke assemblies coupled to one another via a trunnion. Each yoke assembly typically includes a yoke portion and a barrel portion. The yoke and barrel portions are typically a unitarily formed member. Therefore, different yoke and barrel portions are not interchangeable with one another and both are formed from the same material.

SUMMARY

A driveline yoke assembly may include a yoke and a barrel. The yoke may include first and second arms extending from a base. The base may include a first protrusion extending radially therefrom. The barrel may be axially fixed to the yoke and may define an axially extending body having a second protrusion extending radially therefrom and engaged with the first protrusion to transfer rotation from the barrel to the yoke.

An alternate driveline yoke assembly may include a yoke, a barrel, and a retaining member. The yoke may include first and second arms extending from a base. The base may define a first axial bore having a first circumferential groove extending radially therein. The barrel may define an axially extending body located within the first axial bore and defining an outer radial surface. The outer radial surface may have a second circumferential groove disposed therein and axially aligned with the first circumferential groove. The retaining member may be located within the first and second circumferential grooves and may axially secure the yoke to the barrel.

A method of forming a yoke assembly may include forming a yoke having a first coupling portion and selecting a barrel from a group of barrels. The barrels within the group may each have at least one differing feature and may each have a common second coupling portion. The second coupling portion may be configured to engage the first coupling portion of the yoke. The method may further include engaging the second coupling portion from the selected barrel with the first coupling portion of the yoke to couple the yoke for rotation with the selected barrel. The forming the yoke may include forging.

DETAILED DESCRIPTION

With reference toFIG. 1, a vehicle10may include a powertrain12, a driveline14, and wheels16. The driveline14may be driven by the powertrain12and may drive the wheels16. The powertrain12may include an engine18and a transmission20. The transmission20may include an output shaft22engaged with the driveline14.

The engine18may be mounted in an in-line or longitudinal orientation along the axis of the vehicle10. The output of the engine18may be coupled to the transmission20via a clutch (not shown) to transmit rotary power from the engine to the transmission20. The rotary power may be transmitted from the output shaft22of the transmission20to the driveline14. The driveline14may include a propshaft assembly24driven by the output shaft22of the transmission20and driving rotation of the rear axle26, and therefore wheels16.

The propshaft assembly24may include a yoke assembly28and first and second driveline components30,32. A first universal joint34may be formed by the engagement between the yoke assembly28and the first driveline component30and a second universal joint36may be formed by the engagement between the first and second driveline components30,32.

Referring toFIGS. 2-4, the yoke assembly28may include a yoke38, a barrel40, and a cap42. The yoke38may include a base44having first and second arms46,48extending therefrom. The base44may include an axially extending bore50receiving the barrel40therein. The bore50may define a coupling region including a series of radially inward extending protrusions52circumferentially spaced from one another having recesses54disposed therebetween. The protrusions52may form a first set of splines.

The barrel40may include an axially extending body56having an outer radial surface58and an axially extending bore60defining an inner radial surface62. The outer radial surface58may define a coupling region including a series of radially outward extending protrusions64circumferentially spaced from one another having recesses66disposed therebetween. The protrusions64may form a second set of splines. The protrusions52,64on the yoke38and the barrel40may be engaged with one another to transmit rotation from the barrel40to the yoke38. The inner radial surface62of the barrel40may be coupled to the output shaft22of the transmission20. The yoke assembly28may form a slip-yoke assembly. More specifically, the inner radial surface62may include a set of splines67engaged with splines (not shown) on the output shaft22, providing for axial displacement therebetween.

The yoke38and barrel40may additionally include a rotational orientation feature. The yoke38may include a locating recess68having a circumferential width that is different from the remainder of the recesses54and the barrel40may have a corresponding locating protrusion70having a circumferential width that is different from the remainder of the protrusions64. In the present example, the recess68and protrusion70are shown having increased circumferential widths. The recess68and protrusion70may provide for a predetermined and repeatable orientation of the yoke38and barrel40relative to one another during assembly.

The end cap42may be fixed to the base44and may cover the bore50to inhibit entry of debris. The end cap42may be fixed to the base44in a variety of ways including welding. The yoke38and barrel40may be rotationally fixed to one another through the engagement between the protrusions52,64discussed above. The yoke38and barrel40may be axially secured to one another in a variety of ways including an adhesive, a weld, or an interference fit, such as a press fit. If a loose fit is employed, a tolerance ring (not shown) may be used to create a reduced clearance for frictional engagement.

In an alternate arrangement, seen inFIGS. 5 and 6, a yoke assembly128may include a yoke138and a barrel140axially secured to one another through an injection molding process. The yoke assembly128may be generally similar to the yoke assembly28. Therefore, it is understood that the description of the yoke assembly28applies equally to the yoke assembly128, with the exceptions indicated below. The axially extending bore150in the yoke138may include a first circumferential groove172and first and second passages174,176extending from an outer surface of the yoke138into the first circumferential groove172. The first circumferential groove172may intersect the protrusions152. The outer radial surface158of the barrel140may include a second circumferential groove178axially aligned with the first circumferential groove172. The second circumferential groove178may intersect the second protrusions164. A retaining member180may be located within the first and second circumferential grooves172,178and may have a generally annular body.

The retaining member180may be formed from a plastic within the first and second circumferential grooves172,178. The retaining member may be injection molded into the first and second circumferential grooves172,178through the first and second passages174,176in the yoke138. More specifically, forming the retaining member180may include positioning a first mold housing182over the yoke138and in communication with the first passage and positioning a second mold housing184over the yoke138and in communication with the second passage176. The mold housings182,184may each be in communication with a mold material from an injection mold source used to form the retaining member180. As indicated above, the mold material may include a variety of plastics. The mold material may be injected into and conform to the geometry of the first and second circumferential grooves172,178.

With reference toFIGS. 2 and 5, the yoke38,138and barrel40,140may be formed from different materials. For example, the yoke38,138may be formed from steel and the barrel40,140may be formed from iron. The yoke38,138may be formed by forging and the barrel40,140may be formed by casting. In addition to providing for use of different materials for the yoke38,138and the barrel40,140, the separate components may provide for increased flexibility during assembly. For example, a common barrel40,140may be used for a variety of yokes38,138as long as the splines on the given yoke38,138match the splines on the barrel40,140. Conversely, a common yoke38,138may be used for a variety of barrels40,140, as long as the splines on the given barrel40,140match the splines on the yoke38,138.

By way of non-limiting example, and with reference toFIGS. 2 and 7, a common yoke38may be used in combination with either the barrel40(FIG. 2) or with the barrel240(FIG. 7). The barrel240may define a coupling region including a series of radially outward extending protrusions264circumferentially spaced from one another having recesses266disposed therebetween generally similar to the coupling region of the barrel40. However, other features of the barrel240may differ from the barrel40. For example, the barrel240may have a length that is greater than the length of the barrel40. The barrel240may alternatively or additionally include other unique characteristics, such as an additional series of circumferentially spaced radially outward extending protrusions265at an opposite end of the barrel240.

The common coupling region of the barrels40,240may generally provide for interchangeability of the barrels40,240while using a common yoke38. The barrels40,240may form a group of barrels having at least one differing feature (i.e., length and/or protrusions265) and a common coupling portion. A method of forming a yoke assembly may include forming the yoke38having a first coupling portion and selecting a barrel40,240from the group of barrels. The second coupling portion may be configured to engage the first coupling portion of the yoke. The method may further include engaging the second coupling portion from the selected barrel40,240with the first coupling portion of the yoke38to couple the yoke38for rotation with the selected barrel40,240. As indicated above, since the barrels40,240are formed as separate members, the yoke38may be formed by a forging process.