WO2005057035A1

WO2005057035A1 - Plunging constant velocity joint for a propshaft tuned for energy absorption

Info

Publication number: WO2005057035A1
Application number: PCT/US2004/040322
Authority: WO
Inventors: Ramon Kuczera; Michael Miller; Donald Dine; James Lyon
Original assignee: Gkn Driveline North America, Inc.
Priority date: 2003-12-05
Filing date: 2004-12-02
Publication date: 2005-06-23
Also published as: DE112004002352B4; JP2007513305A; JP4664925B2; DE112004002352T5

Abstract

An energy absorbing plunging constant velocity joint has an outer joint part (50) and an outer extended axial range. The joint also includes an inner joint part (44) disposed within said outer joint part and a plurality of torque transmitting mechanisms (58) guided between said outer joint part and said inner joint part within a normal axial range. The joint further includes one or more energy absorption surfaces distal to the normal axial range and located in the extended axial range upon said outer joint part. The energy absorption surface ( 71 , 48 ) on the outer joint part interferes with said inner joint part or at least one of said pluralit,, of torque transmitting mechanisms when said outer joint part is operated beyond said normal axial range.

Description

PLUNGING CONSTANT VELOCITY JOINT FOR A PROPSHAFT TUNED FOR ENERGY ABSORPTION

Technical Field The present invention relates generally to motor vehicle propeller shafts, and more particularly concerns a constant velocity joint having improved crash-worthiness and energy absorption capabilities within a propeller shaft of a motor vehicle. Background Of The Invention Constant velocity joints are common components in automotive vehicles. Typically, constant velocity joints are employed where transmission of a constant velocity rotary motion is desired or required. Common types of constant velocity joints include end motion or plunging and fixed motion designs. Of particular interest is the end motion or plunging type constant velocity joints, which include a tripod joint, a double offset joint, a cross groove joint, and a cross groove hybrid. Of these plunging type joints, the tripod type constant velocity joint uses rollers as torque transmitting members, and the others use balls as torque transmitting members. Typically, these types of joints are used on the inboard (toward the center of the vehicle) on front sideshafts and on the inboard or outboard side for sideshafts on the rear of the vehicle and on the propeller shafts found in rear wheel drive, all wheel drive, and four-wheel drive vehicles.

Propeller shafts are commonly used in motor vehicles to transfer torque and rotational movement from the front of a vehicle to a rear axle differential such as in a rear wheel and all wheel drive vehicles. Propeller shafts are also used to transfer torque and rotational movement to the front axle differential in four-wheel drive vehicles. In particular, two-piece propeller shafts are commonly used when larger distances exist between the front drive unit and the rear axle of the vehicle. Similarly, side shafts are commonly used in motor vehicles to transfer torque from a differential to the wheels. The propeller shaft and side shafts are connected to their respective driving input and output components by a joint or series of joints. Joint types used to connect the propeller shaft and side shafts include Cardan, Rzeppa, tripod and various ball type joints. In addition to transmitting torque and rotary motion, propeller shafts and side shafts allow for axial motion in many automotive applications. Specifically, axial motion is designed into two-piece propeller shafts by using an end motion or plunging type constant velocity joint.

Besides transferring mechanical energy and accommodating axial movement, it is desirable for plunging constant velocity joints to have adequate crash- worthiness. In particular, it is desirable for the constant velocity joint to be shortened axially preventing the propeller shaft or side shaft from buckling, penetrating the passenger compartment, or damaging other vehicle components in close proximity of the propeller shaft or side shaft. In many crash situations, the vehicle body shortens and deforms by absorbing energy that reduces the acceleration; further protecting the occupants and the vehicle. As a result, it is desirable for the propeller shaft to be able to reduce in length during the crash, allowing the constant velocity joint to travel beyond its operational length. It is also desirable for the constant velocity joint within the propeller shaft to absorb a considerable amount of the deformation energy during the crash. Reduction of the propeller shaft length during a crash situation is often achieved by having the propeller shaft telescopically collapse and energy absorb thereafter.

In telescopic propeller shaft assemblies, the joint must translate beyond the constant velocity joint limitation before the telescopic nature of the propeller shaft is effectuated. In some designs, the propeller shaft must transmit the torque as well as maintain the ability to telescope. In other designs, the telescopic nature of the joint only occurs after destruction of the joint, joint cage or some type of joint retaining ring. Still in other designs, the joint must first translate the balls off the race area before the telescopic attribute can be used for axial joint displacement. The limitation of the telescopic ability is that the constant velocity joint must be compromised before axial displacement can occur in a crash situation. Therefore, there is a desire to have a constant velocity joint that can accommodate the axial displacement during a crash. Furthermore, the energy absorption only occurs after the functional limit of the constant velocity joint has been surpassed. This causes a time delay in the energy absorption of the propeller shaft. Then and only then, the energy absorption is accomplished and typically has a force step or impulse energy absorption pattern. After the initial energy absorption, typically, there is no further energy absorption in the propeller shaft. In another situation there is further energy absorption, but only after the joint balls successfully translate off the joint race and onto the propeller shaft. Therefore, there is a desire to have a constant velocity joint that has a controlled or tuned force energy absorption profile over a range of the joint's axial travel distance, especially when the normal operational range of the joint has been surpassed. It would be advantageous to have the above-mentioned features in the tripod joint. Automotive manufactures and suppliers commonly know the tripod constant velocity joint as a GI type joint. The invention, here below, relates to this type of joint. A tripυd joint is used for accommodating angular and axial displacements in a propeller shaft while transmitting rotational motion and torque. Propeller shafts and side shafts are used, in turn, to connect a drive unit, i.e. transmission, to a rear axle gearbox or differential. The tripod joint comprises an outer joint part having innerly a plurality of outer bores circumf erentially spaced between a plurality of longitudinally extending tracks. Each track has a bottom spaced between two oppositely disposed longitudinal sidetracks. There is an inner joint part disposed within said outer joint part having a plurality of spider sides circumferentially spaced between a plurality of trunions. Each trunion has a top and an inner race where a plurality of rollers having an inner bore are mounted on said inner race of each said trunion. Angular and axial displacements occur between the inner joint and the outer joint.

It would also be advantageous to have the above-mentioned features in a cross groove joint. The cross groove constant velocity joint is commonly know by automotive manufactures and suppliers as a VL type joint and the invention, here below, relates to this type of joint. A VL joint is used for accommodating rotary and axial displacements in a propeller shaft of a motor vehicle and for connecting a drive unit to a rear axle gearbox, having at least two articulatably connected shaft portions. The joint has an outer joint part with outer ball tracks, an inner joint part with inner ball tracks, a plurality of torque transmitting balls each guided in outer and inner ball tracks associated with one another. The associated outer ball tracks on the one hand and inner ball tracks on the other hand, forming angles of intersection in respect of the central axis of the joint, which are of identical size but are set in opposite directions. The balls are held in a constant velocity plane when the joint is axially displaced or articulated by a ball cage, which is provided with a plurality of cage windows each accommodating one of the balls. The outer joint part is connected to a hollow shaft and the inner joint part is connected to a connecting shaft allowing axial displacement.

It would be further advantageous to have the above-mentioned features in the cross groove hybrid joint. The cross groove hybrid constant velocity joint is commonly known by automotive manufactures and suppliers as a SX or XL type joint and the invention, here below, relates to this type of joint. A SX joint is used for accommodating angular and axial displacements in a propeller shaft. Propeller shafts, in turn, are used to connect a drive unit, i.e., transmission, to a rear axle gearbox, having at least two articulatable connected shaft portions. The joint has an outer joint part with outer ball tracks, an inner joint part with inner ball tracks, a plurality of torque transmitting balls each guided in outer and inner ball tracks associated with one another. The associated outer ball tracks on the one hand and inner ball tracks on the other hand, forming angles of intersection in respect of the central axis of the joint, which are of identical size but are set in opposite directions. These associated outer and inner ball tracks alternate with a corresponding pairs of the inner ball tracks and the outer ball tracks being axially straight in respect of the axis. The balls are held in a constant velocity plane when the joint is axially displaced or articulated by a ball cage, which is provided with a plurality of cage windows each accommodating one of the balls. The outer joint part is connected to a hollow shaft and the inner joint part is connected to a connecting shaft allowing axial displacement.

It would also be advantageous to have the above-mentioned features in the double offset joint. The double offset constant velocity joint is commonly known by automotive manufactures and suppliers as a DO type joint and the invention, here below, relates to this type of joint. Double offset joints are used for accommodating angular and axial displacements in a propeller shaft. Propeller shafts, in turn, are used to connect a drive unit, i.e. transmission, to a rear differential. The differential has an outer joint part in which a plurality of linear ball tracks are axially formed on an inner cylindrical surface thereof. This outer joint part contains an inner joint part in which a plurality of linear ball tracks are axially formed on an outer spherical surface thereof and an equal number of torque transmitting balls retained by cage windows in a ball cage and located in a pair of outer and inner ball tracks. Since the spherical center of the outer spherical face of the cage and the spherical center of the inner concave face thereof are offset to the opposite side in the axial direction from the center of the cage windows, they are called "double offset type". When this kind of joint transmits a torque while taking an operating angle, the cage rotates to the position of the torque transmitting balls moving in the ball tracks in response to the inclination of the inner joint part to retain the torque transmitting balls on the constant velocity plane bisecting the operating angle. Furthermore, as the outer joint part and the inner joint part relatively displace in the axial direction, a slipping occurs between the outer spherical face of the cage and the inner cylindrical surface of the outer joint part to ensure a smooth axial displacement (plunging).

Summary Of The Invention The present invention is directed toward a constant velocity joint for use in a vehicle driveline having at least one energy absorption element for improved crash- worthiness and energy absorption. In particular, at least one energy absorption element of the constant velocity joint described herein is tuned to control joint energy absorption for axial displacement beyond the normal axial travel range of the joint. An embodiment of the present invention provides an energy absorbing plunging constant velocity joint for improved crash-worthiness. In particular, a constant velocity joint has an outer joint part having innerly a normal axial range, an extended axial range, and a plurality of outer bores circumferentially spaced between a plurality of longitudinally extending tracks. Each track has a bottom spaced between two oppositely disposed sidetracks. Additionally, an inner joint part is disposed within said outer joint part and has a plurality of spider sides circumferentially spaced between a plurality of trunions. Each trunion has a top and an inner race. In addition, a plurality of rollers each having an inner bore are mounted adjacent to the inner race of each trunion. Angular and axial displacement occur between the inner joint part and the outer joint part. At least one energy absorption surfaces is located in the extended axial range on the outer joint part. Wherein the energy absorption surface interferes with the inner joint part when the joint is operated beyond said normal axial range, the joint absorbs the thrust energy. A further embodiment of the present invention provides an energy absorbing plunging constant velocity joint for improved crash-worthiness. In particular, a constant velocity joint has an outer joint part, an inner joint part, a plurality of torque transmitting balls, and a ball cage having cage windows for retaining the torque transmitting balls in the outer and the inner ball tracks of the outer and the inner joint parts. The torque transmitting balls are retained in a constant velocity plane by the ball cage and guided by corresponding pairs of the outer and the inner ball tracks. The outer and the inner ball tracks form angles of intersection with respect to an axis where the angles are identical in size but set in opposite directions to one another. The outer joint part and the inner joint part operate in a normal axial range when transmitting torque in a propeller shaft. There is an inner extended axial range and an outer extended axial range, which can accommodate axial motion when the inner joint part and the outer joint part are thrust beyond the normal axial range. There is at least one energy absorption surface located in the outer extended axial range or in the inner extended axial range. The energy absorption surface interferes with at least one of the torque transmitting balls when the joint is operated beyond said normal axial range, allowing the joint to absorb the thrust energy. A yet further embodiment of the present invention provides an energy absorbing plunging constant velocity joint for improved cr sh- worthiness. In particular, a constant velocity joint has an outer joint part, an inner joint part, a plurality of torque transmitting balls, and a ball cage having cage windows for retaining the torque transmitting balls in the outer and the inner ball tracks of the outer and the inner joint parts. The torque transmitting balls are retained in a constant velocity plane by the ball cage and guided by corresponding pairs of the outer and the inner ball tracks. The outer and the inner ball tracks form angles of intersection with respect to an axis where the angles are identical in size but set in opposite directions to one another. The corresponding pairs of the outer and the inner ball tracks alternate with other corresponding pairs of the inner ball tracks and the outer ball tracks being axially straight in respect of the axis. The outer joint part and the inner joint part operate in a normal axial range when transmitting torque in a propeller shaft. There is an inner extended axial range and an outer extended axial range, which can accommodate axial motion when the inner joint part and the outer joint part are thrust beyond the normal axial range. There is at least one energy absorption surface located in the outer extended axial range or in the inner extended axial range. The energy absorption surface interferes with at least one of the torque transmitting balls when the joint is operated beyond said normal axial range, allowing the joint to absorb the thrust energy.

A further embodiment of the present invention provides an energy absorbing plunging constant velocity joint for improved crash-worthiness. In particular, a constant velocity joint has an outer joint part, an inner joint part, a plurality of torque transmitting balls, and a ball cage having cage windows for retaining the torque transmitting balls in the outer and the inner ball tracks of the outer and the inner joint parts. The torque transmitting balls are retained in a constant velocity plane by the ball cage and guided by corresponding pairs of the outer and the inner ball tracks. The ball cage has an outer spherical face guided in contact by an inner bore of the outer joint part and an inner concave face rotatably guided in contact by the convex face of the inner joint part. The outer joint part having a normal axial range, an extended axial range, and at least one energy absorption surfaces located in the extended axial range. Wherein the energy absorption surface interferes with at least one of the torque transmitting balls when the joint is operated beyond the normal axial range, allowing the joint to absorb the thrust energy.

A feature of the present invention is that the constant velocity joint absorbs energy within an extended axial range when the joint is thrust beyond its normal axial range. The present invention itself, together with further objects and intended advantages, will be best understood by reference to the following detailed description, taken in conjunction with the accompanying drawings. Brief Description Of The Drawings For a more complete understanding of this invention, reference should now be made to the embodiments illustrated in greater detail in the accompanying drawings and described below by way of examples of the invention. In the drawings: Figure 1 shows a plan view of a four-wheel drive vehicle driveline in which the present invention may be used to advantage.

Figure 2 shows a half-sectional view of a vehicle propeller shaft assembly comprising one or more constant velocity joints in accordance with one embodiment of the present invention.

Figure 3 shows a half-sectional view of a constant velocity joint in accordance with one embodiment of the present invention in a propeller shaft assembly.

Figure 4 shows a partial view of a constant velocity joint in accordance with an alternative embodiment of the present invention. Figure 5 shows a partial view of a constant velocity joint in accordance with an alternative embodiment of the present invention. Figure 6 shows a sectional view of an outer joint part of a constant velocity joint in accordance with the present invention.

Figure 7 shows an end view of an outer joint part of a constant velocity joint in accordance with the present invention.

Figure 8 shows a plan view of an inner joint part of a constant velocity joint in accordance with the present invention.

Figure 9 shows a cross-sectional view of an inner joint part of Figure 8.

Figure 10 shows a half-sectional view of a constant velocity joint in accordance with one embodiment of the present invention in a propeller shaft assembly. Figure 11 shows a partial view of a constant velocity joint in accordance with alternative embodiments of the present invention. Figure 12 shows a partial view of a constant velocity joint in accordance with alternative embodiments of the present invention.

Figure 13 shows a layout view of an outer ball track according to one embodiment of the present invention. Figure 14 shows a layout view of an inner ball track according to one embodiment of the present invention. Figure 15 shows a half-sectional view of a constant velocity joint in accordance with one embodiment of the present invention in a propeller shaft assembly.

Figure 16 shows a partial view of a constant velocity joint in accordance with alternative embodiments of the present invention.

Figure 17 shows a partial view of a constant velocity joint in accordance with alternative embodiments of the present invention.

Figure 18 shows a layout view of an outer ball track according to alternative embodiments of the present invention. Figure 19 shows a layout view of an inner ball track according to alternative embodiments of the present invention.

Figure 20 shows a half-sectional view of a constant velocity joint in accordance with one embodiment of the present invention in a propeller shaft assembly.

Figure 21 shows a partial view of a constant velocity joint in accordance with alternative embodiment of the present invention.

Figure 22 shows a partial view of a constant velocity joint in accordance with alternative embodiment of the present invention.

Figure 23 shows a layout view of an outer ball track according to one embodiment of the present invention. Detailed Description Of The Invention In the following description, various operating parameters and components are described for one constructed embodiment. These specific parameters and components are included as examples and are not meant to be limiting. While the invention is described with respect to an apparatus having improved crash-worthiness within a propeller shaft of a vehicle, the following apparatus is capable of being adapted for various purposes including automotive vehicle drive axles, and other vehicles and non-vehicle applications which require collapsible propeller shaft assemblies. Referring now to Figure 1, there is shown a plan view of four-wheel drive vehicle driveline 10 wherein a constant velocity joint 11 in accordance with the present invention may be used to advantage. The driveline shown in Figure 1 is typical for a four-wheel drive vehicle, however, it should be noted that the constant velocity joint 11 of the present invention can also be used in rear wheel drive only vehicles, front wheel drive only vehicles, all wheel drive vehicles, and four-wheel drive vehicles. The vehicle driveline 10 includes an engine 14 that is connected to a transmission 16 and a power takeoff unit such as a transfer case 18. The front differential 20 has a right hand side shaft 22 and left hand side shaft 24, each of which are connected to a wheel and deliver power to the wheels. On both ends of the right hand front side shaft 22 and the left hand front side shaft 24 are constant velocity joints 12. A front propeller shaft 25 connects the front differential 20 to the transfer case 18. A propeller shaft 26 connects the transfer case 18 to the rear differential 28, wherein the rear differential 28 is coupled to a rear right hand side shaft 30 and a rear left hand side shaft 32, each of which is connected to a respective wheel. Constant velocity joints 12 are located on both ends of the side shafts 30, 32 that connect the rear wheels to the rear differential 28. The propeller shaft 26, shown in Figure 1, is a two-piece propeller shaft. Each end includes a rotary joint 34 that may comprise a Cardan joint or any one of several types of constant velocity joints or non-constant velocity joints. Between the two pieces of the propeller shaft 26 is a high-speed constant velocity joint 11 in accordance with the present invention as well as a support 36 such as an intermediate shaft bearing. The constant velocity joints 11, 12, 34 transmit power to the wheels through the propeller shaft 26, front propeller shaft 25 and side shafts 22, 24, 30, 32 even if the wheels or the shafts 25, 26 have changing angles due to the steering or raising or lowering of the suspension of the vehicle. The constant velocity joints 11, 12, 34 may be any of the standard types known and used to advantage, such as a plunging tripod, a cross-groove joint, a cross-groove hybrid joint, or a double offset joint or any other type of constant velocity joint.

Figure 2 shows a half-sectional view of a vehicle propeller shaft 26 assembly comprising one or more constant velocity joints 11, 34 in accordance with one embodiment of the present invention. The propeller shaft 26 assembly may include one, two or a combination of constant velocity joints 11, 34. The constant velocity joint can be of a monobloc, disc, flanged, or other styles of design know to those in the art. The propeller shaft 26 assembly transfers torque from the transmission 16 to the rear differential 28 by way of the propeller shaft 26. The constant velocity joints 11, 34 are axially plungeable. T he constant velocity joints 11, 34 have an inner joint part 38 and an outer joint part 40. The outer joint part 40 of constant velocity joint 11 is connected to one end of a hollow shaft 42 by, for example, a friction weld. The hollow shaft 42 being defined as having cylindrical shell having an inner diameter that is smaller than its outer diameter and two open ends. The other end of the hollow shaft 42 is connected to a rotary joint 35 that is connectable to a rear differential 28 or a transmission 16 depending upon the directional orientation of the propeller shaft 26. Into the inner joint part 38 there is inserted a connecting shaft 44 that, at a certain distance from the joint 11, is supported by a shaft bearing 36.

Similarly, in combination or alternatively, the outer joint part 40 of constant velocity joint 34 is connected to one end of a hollow shaft 43 by, for example, not shown, a bolted connection. The other end of the hollow shaft 43 is connected to a shaft bearing 36 on the opposite side of connecting shaft 44. Into the inner joint part 38 there is inserted a connecting shaft 45 that is connectable to a transmission 16 or a rear differential 28 depending upon the directional orientation of the propeller shaft 26. The propeller shaft 26 assembly transfers torque from the transmission 16 to the rear differential 28 by way of the propeller shaft 26. In addition to torque transfer, the propeller shaft 26 can accommodate axial and angular displacements within the constant velocity joints 11, 34. Where axial movement and articulation of the hollow shafts 42, 43 are relative to the connecting shafts 44, 45. Axial movement is relative to the shaft centerlines. In certain crash situations, however, the connecting shaft 44, 45 will thrust axially toward the shafts 42, 43, beyond the normal operating range of the joint while engaging a tuned energy absorption surface. The tuned energy absorption surface extends over an extended axial range of the constant velocity joints 11, 34. Energy may be absorbed until the extended axial range is exceeded and the joint parts are released into the hollow shafts 42, 43 or are impeded by the hollow shafts 42, 43. The required thrust for axial movement may be increased or decreased by increasing or decreasing the amount of interference caused by the energy absorption surface.

For clarity in the disclosure that follows, the inner joint part 52 is shown as a cylinder in the half-sectional views of Figures 3, 4 and 5 allowing the sectional view to depict one of the rollers 58 in a track 60. Reference may also be made to Figures 6, 7, 8 and 9 when Figures 3, 4 or 5 are discussed.

Figure 3 shows a half-sectional view of a constant velocity joint 11 in accordance with one embodiment of the present invention in a propeller shaft assembly. The joint 11 is an axially plungeable constant velocity joint of the tripod type and comprises an outer joint part 50, an inner joint part 52, and a plurality of rollers 58. The outer joint part 50 has innerly a normal axial range N, an extended axial range E, and a plurality of outer bores 74 circumferentially spaced between a plurality of longitudinally extending tracks 60, each track 60 having a bottom 86 spaced between two oppositely disposed sidetracks 80. The inner joint part 52 is disposed within said outer joint part 50 and has a plurality of spider sides 54 circumferentially spaced between a plurality of trunions 53. Each of the trunions 53 has a top 55 and an inner race 56. The plurality of rollers 58 have an inner bore 59. Each of the rollers 58 are mounted on the inner race 56 of one of the trunions 53. Thus, the outer joint part 50 and the inner joint part 52 are driveably connected through the rollers 58 located in the longitudinally extending tracks 60, allowing angular and axial displacement between the inner joint part 52 and the outer joint part 50. The outer joint part 50 is connected to a hollow shaft 42 that is fixed to the outer joint part by, for example, a friction weld. The hollow shaft 42 may also be flanged and connected to the outer joint part by way of, for example, bolts.

Into the inner joint part 52 there is inserted a connecting shaft 44. A plate cap 46 is secured to the outer joint part 50. A convoluted boot 47 seals the plate cap 46 relative to the connecting shaft 44. The other end of the joint 11 at the cylindrical open end 66, i.e., towards the hollow shaft 42, is sealed by a grease cover 48. In addition, the grease cover 48 may provide some energy absorption should the connecting shaft 44 be thrust beyond the extended axial range E of constant velocity joint 11. The constant velocity joint 11 is designed to operate in its normal axial range N until, however, compression from a crash or an unintended thrust is applied forcing the inner joint part 52 and the rollers 58 into or through the extended axial range E. In this embodiment of the present invention, the joint has a tuned energy absorption surface 70, which is a circlip 71. The circlip 71 is circumferentially located in the extended axial range E and coupled to the inside surface 51 of the outer joint part 50. The circlip 71, in this embodiment, is an annular ring, made from a deformable material, preferably metal or plastic, and positionable in the outer joint part 50 so as to reside in the longitudinally extending tracks 60. When the connecting shaft 44 along with the inner joint part 52 and the rollers 58 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the extended axial range E of the joint 11, the rollers 58, the tops 55 or the spider sides 54 of the inner joint part 52 will interfere with or be impeded by the circlip 71. The impediment of the circlip 71 causes an increase in the thrust required for axial motion, allowing energy to be absorbed by the constant velocity joint 11 and the propeller shaft 26. While impeding the motion of the joint 11 components, the circlip 71 may be dislodged, deformed or broken. The circlip 71 can be tuned to achieve different force levels, allowing for design of a controlled energy absorption profile within the constant velocity joint 11. The tuning may be accomplished by changing the size, the shape, the material, or the location of the circlip 71. There may be more than one circlip 71, although not shown, located within the extended axial range E of the constant velocity joint 11.

Thus, under normal operating conditions, the inner joint part 52 and the rollers 58 will operate in the normal axial range N of the constant velocity joint 11. In certain crash situations, however, the connecting shaft 44 along with the inner joint part 52 and the rollers 58 will be thrust toward the hollow shaft 42 allowing track and bore energy to be absorbed along the extended axial range E caused by the impediment of the circlip 71 upon the inside surface 51 of the outer joint part 50. It is contemplated that the circlip 71 could be a foreign body residing upon the extended axial range E absorbing plastic energy. Figure 4 shows a partial view of a constant velocity joint in accordance with an alternative embodiment of the present invention. In this embodiment, the joint has a tuned energy absorption surface 73, which is a bore surface 75. The bore surface 75 is circumferentially located in the extended axial range E, has an inclination Θ and is coupled to the outer bore 74 of the outer joint part 50 between any two longitudinally extending tracks 60. In addition to or in the alternative, the bore surface 75 can have multiple inclinations, stepped inclination, or variable inclination. The bore surface 75 may be located between any one or more longitudinally extending tracks 60 or entirely upon all of the outer bores 74 in the extend axial range E. The bore surface 75 may be manufactured by layering, i.e. welding, material upon the outer bore 74 or by undercutting, while machining, the outer bore surface 74. One embodiment contemplates the bore surface 75 to be manufactured from the same material as the outer joint part 50 by reducing the outer bore 74 diameter forming an inclination Θ in the extended axial range E during the machining process. However, one in the trade would recognize that the bore surface 75 could be accomplished, among other ways, by tacking, staking, or riveting a material upon the outer bore 74 (see Figure 7). Thus, when the connecting shaft 44 along with the inner joint part 52 and the rollers 58 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the extended axial range E of the joint 11, the spider sides 54 of the inner joint part 52 will interfere with or be impeded by the bore surfaces 75. The impediment of the bore surfaces 75 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 11 and the propeller shaft 26. The bore surfaces 75 can be tuned to achieve different force levels, allowing for the design of a controlled energy absorption profile within the constant velocity joint 11. The tuning may be accomplished by changing the size, the shape, the material, or the location of the bore surfaces 75. Any number of bore surfaces 75 may be combined with any number of circlips 71, as in Figure 3, in the extended axial range E of the constant velocity joint 11 to achieve a tuned and controlled energy absorption rate. Thus, under normal operating conditions, the inner joint part 52 and the rollers

58 will operate in the normal axial range N of the constant velocity joint 11. In certain crash situations, however, the connecting shaft 44 along with the inner joint part 52 and the rollers 58 will be thrust toward the hollow shaft 42 allowing bore energy to be absorb along the extended axial range E caused by the impediment of the bore surface 75 of the outer joint part 50

Additionally an alternative embodiment of the joint having a tuned energy absorption surface 87, which is a bottom surface 88, is as shown in Figure 4. The bottom surface 88 is circumferentially located in the extended axial range E, has an inclination Θl and is coupled to the bottom 86 of the outer joint part 50 between any two oppositely disposed sidetracks 80 of the longitudinally extending tracks 60. In addition to or in the alternative, the bottom surface 88 can have multiple inclinations, stepped inclination, or variable inclination. There are three inclinations shown in Figure 4 for the bottom surface 88 of this embodiment. The bottom surface 88 may be located between any of the one or more longitudinally extending tracks 60 in the extended axial range E. The bottom surface 88 may be manufactured by layering, i.e. welding, material upon the bottom 86 or by undercutting, while broaching, the bottom surface 88. One embodiment contemplates the bottom surface 88 to be manufactured from the same material as the outer joint part 50 by reducing the bottom surface 88 diameter forming an inclination Θl in the extended axial range E during the machining process. However, one in the trade would recognize that the bottom surface 88 could be accomplished, among other ways, by tacking, staking, or riveting a material upon the bottom 86 (see Figure 7). Thus, when the connecting shaft 44 along with the inner joint part 52 and the rollers 58 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the extended axial range E of the joint 11, the tops 55 of the inner joint part 52 will interfere with or be impeded by the bottom surface 88. The impediment of the bottom surface 88 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 11 and the propeller shaft 26. The bottom surface 88 can be tuned to achieve different force levels, allowing for the design of a controlled energy absorption profile within the constant velocity joint 11. The tuning may be accomplished by changing the size, the shape, the material, or the location of the bottom surface 88. Any number of bottom surfaces 88 may be combined with any number of circlips 71 or bore surfaces 75 in the extended axial range E of the constant velocity joint 11 to achieve a tuned and controllable energy absorption rate.

Thus, under normal operating conditions, the inner joint part 52 and the rollers 58 will operate in the normal axial range N of the constant velocity joint 11. In certain crash situations, however, the connecting shaft 44 along with the inner joint part 52 and the rollers 58 will be thrust toward the hollow shaft 42 allowing bottom energy to be absorb along the extended axial range E caused by the impediment of the bottom surface 88 of the outer joint part 50. Figure 5 shows a partial view of a constant velocity joint in accordance with an alternative embodiment of the present invention. In this embodiment, the joint has a tuned energy absorption surface 81, which is a track surface 82. The track surface 82 has a taper 84 and is located on a sidetrack 80 in the extended axial range E of the longitudinally extending track 60 of the outer joint part 50. There can be one or more track surfaces 82 located on anyone of the other sidetracks 80. The taper 82 may extend linearly over the extended axial range E as shown. Alternatively, not shown, the track surface may have a variable taper or a stepped taper of increasing or decreasing size. The track surface 82 may be manufactured by layering, i.e. welding, material upon the sidetrack 80 or by undercutting, while broaching, the track surface 82. One embodiment contemplates the track surface 82 is to be manufactured from the same material as the outer joint part 50 by reducing the track surface 82 taper in the extended axial range E during the machining process. However, one in the trade would recognize that the track surface 82 could be accomplished, among other ways, by tacking, staking, or riveting a material upon the bottom 86 (see Figure 7). Thus, when the connecting shaft 44 along with the inner joint part 52 and the rollers 58 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the extended axial range E of the joint 11, the rollers 58 will interfere with or be impeded by the track surface 82. The impediment of the track surface 82 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 11 and the propeller shaft 26. The track surface 82 can be tuned to achieve different force levels, allowing for the design of a controlled energy absorption profile within the constant velocity joint 11. The tuning may be accomplished by changing the size, the shape, the material, or the location of the track surface 82.

Thus, under normal operating conditions, the inner joint part 52 and the rollers 58 will operate in the normal axial range N of the constant velocity joint 11. In certain crash situations, however, the connecting shaft 44 along with the inner joint part 52 and the rollers 58 will be thrust toward the hollow shaft 42 allowing track energy to be absorb along the extended axial range E caused by the impediment of the rollers 58 of the inner joint part 52 upon the track surface 82 of the outer joint part 50. Figure 6 shows a sectional view of an outer joint part of a constant velocity joint in accordance with the present invention. The outer joint part 50 is shown having an outer bore 74 and a longitudinally extending track 60. The longitudinally extending track 60 having a bottom 86 spaced between two oppositely disposed longitudinal sidetracks 80. In the extended axial range, there are energy absorption surfaces 73, 81, 87, which are a bore surface 75, a track surface 82, and a bottom surface 88, respectfully.

The bore surface 75 is located on the outer bore 74, the track surface 82 is located on the sidetrack 80, and the bottom surface 88 is located on the bottom 86, all of which are in the extended axial range of the outer joint part 50.

The one or more track surfaces 82, the one or more circlips 71, the one or more bottom surfaces 88, and the one or more bore surfaces 75 are combinable to achieve a controlled and tuned energy absorption rate when the constant velocity joint 11 is operated beyond it's normal axial range N. Figure 10 shows a half-sectional view of a constant velocity joint 111 in accordance with one embodiment of the present invention in a propeller shaft assembly. The joint 111 is an axially plungeable constant velocity joint of the cross- groove type. The constant velocity joint 11 comprises an outer joint part 150, an inner joint part 152, a ball cage 154 and more than one torque transmitting balls 156 each held in a cage window 158. The outer joint part 150 comprises a cylindrical open end 166 located proximate to the hollow shaft 142, outer ball tracks 160 which longitudinally extend over the length of the outer joint part 150, having a normal axial range N and an outer extended axial range E. The inner joint part 152 comprises inner ball tracks 161 which longitudinally extend over the length of the inner joint part 152, having a normal axial range N and an inner extended axial range IE. The inner extended axial range IE of the inner joint part 152 is correspondingly positioned in opposite direction, about the normal axial range N, from the outer extended axial range E of the outer joint part 150. Each inner ball track 161 is associated with a corresponding outer ball track 160 forming angles of intersection with respect to an axis. The angles are identical in size but set in opposite directions and corresponding to the inner ball tracks 161 and the outer ball tracks 160. The length of each inner ball track 161 is commensurate with the length of each outer ball track 160, although shown in the figure as having different lengths for clarity of the inventive aspects. Alternatively, it can be recognized that the inner ball tracks 61 and the outer ball tracks 160 can have varying lengths, the shorter of which correspondingly commensurate to the angles of intersection of the longer of the two. Thus, the outer joint part 150 and the inner joint part 152 are driveably connected through the torque transmitting balls 156 located in the ball tracks 160, 161; there being one torque transmitting ball 156 for each corresponding pair of ball tracks 160, 161. The torque transmitting balls 156 are positioned and maintained in a constant velocity plane by the ball cage 154, wherein the ball cage 154 is located between the two joint parts 150, 152. The constant velocity joint 111 permits axial movement since the ball cage 154 is not positionably engaged to the inner joint part 152 and the outer joint part 150. The outer joint part 150 is connected to a hollow shaft 142 that is fixed to the outer joint part by, for example, a friction weld. The hollow shaft 142 may also be flanged and connected to the outer joint part by way of, for example, bolts.

Into the inner joint part 152 there is inserted a connecting shaft 144. A plate cap 146 is secured to the outer joint part 150. A convoluted boot 147 seals the plate cap 146 relative to the connecting shaft 144. The other end of the joint 111 at the cylindrical open end 166, i.e., towards the hollow shaft 142, is sealed by a grease cover 148. In addition, the cover 148 may provide some energy absorption should the connecting shaft 144 be thrust beyond the extended axial range E of constant velocity joint 111. The constant velocity joint 111 is designed to operate in it normal axial range N until, however, compression from a crash or an unintended thrust is applied forcing the inner joint part 152, the ball cage 154, and the torque transmitting balls 156 into or through the extended axial ranges E, IE of both joint components.

In this embodiment of the present invention, the joint has a tuned energy absorption surface 174, which is a circlip 176. The circlip 176 is circumferentially located in the outer extended axial range E and coupled to the outer joint part 150. The circlip 176, in this embodiment, is an annular ring, made from a deformable material, preferably metal or plastic, and positionable in the outer joint part 150 so as to reside in the outer ball tracks 160. When the connecting shaft 144 along with the inner joint part 152, the torque transmitting balls 156 and the ball cage 154 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the outer extended axial range E of the joint 111, the torque transmitting balls 156 will interfere with or be impeded by the circlip 176. The impediment of the circlip 176 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 111 and the propeller shaft 126. The circlip 176 can be tuned to achieve different force levels, allowing for design of a controlled energy absorption profile within the constant velocity joint 111. The tuning may be accomplished by changing the size, the shape, the material, or the location of the circlip 176. There may also be more than one circlip 176 located within the outer extended axial range E of the constant velocity joint 111. In addition or alternatively, the circlip 176 may be circumferentially located in the inner extended axial range IE and coupled to the inner joint part 152 (not shown in Fig. 3). When the connecting shaft 144 along with the inner joint part 152, the torque transmitting balls 156 and the ball cage 154 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the inner extended axial range IE of the joint 111, the torque transmitting balls 156 will interfere with or be impeded by the circlip 176. The impediment of the circlip 176 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 111 and the propeller shaft 126. Thus, under normal operating conditions, the torque transmitting balls 156 will operate in the normal axial range N of the constant velocity joint 111. In certain crash situations, however, the connecting shaft 144 along with the inner part 152, the ball cage 154 and the torque transmitting balls 156 will be thrust toward the hollow shaft 142 allowing track and bore energy to be absorb along the outer extended axial range E or the internal extended axial range IE caused by the impediment of the circlip 176 upon the outer joint part 150 or inner joint part 152, respectfully. When the joint is positioned in the outer extended axial range E, it is correspondingly positioned in the inner extended axial range IE. It is contemplated that the circlip 176 could be a foreign body, having the same energy absorbing effect as the ring given in this embodiment, residing upon the outer extended axial range E or inner extended axial range IE absorbing plastic energy.

Figure 11 shows a. partial view of a constant velocity joint in accordance with alternative embodiments of the present invention. In this embodiment, there is a tuned energy absorption surface 180, which is a bore surface 182. The bore surface 182 is circumferentially located in the extended axial range E, has an inclination Θ and is coupled to the inner bore 64 of the outer joint part 150 between any two outer ball tracks 160. In addition to or in the alternative, the bore surface 182 can have multiple inclinations, stepped inclination, or variable inclination. The bore surface 182 may be located between any set of one or more outer ball tracks 160 or upon the entire inner bore surface 164 in the outer extend axial range E. The bore surface 182 may be manufactured by layering, i.e. welding, material upon the inner bore surface 164 of the outer joint part 150 or by undercutting, while machining, the inner bore surface 164. One embodiment contemplates the bore surface 182 to be manufactured from the same material as the outer joint part 150 by reducing the inner bore 164 diameter and forming an inclination Θ in the outer extended axial range E during the machining process. However, one in the trade would recognize that the bore surface 182 could be accomplished, among other ways, by tacking, staking, or riveting a material upon the inner bore 164. Thus, when the connecting shaft 144 along with the inner joint part 152, the torque transmitting balls 156, and the ball cage 154 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the outer extended axial range E of the joint 111, the ball cage 154 will interfere with or be impeded by the bore surfaces 182. The impediment of the bore surfaces 182 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 111 and the propeller shaft 126. The bore surfaces 182 can be tuned to achieve different force levels, allowing for design of a controlled energy absorption profile within the constant velocity joint 111. The tuning may be accomplished by changing the size, the shape, the material, or the location of the bore surfaces 182.

In addition or alternatively, the energy absorption surface 180 may be an inner energy absorption surface 181 located in the inner extended axial range IE on the outer face 162 of the inner joint part 152. When the connecting shaft 144 along with the inner joint part 152, the torque transmitting balls 156, and the ball cage 154 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the inner extended axial range IE of the joint 111, the ball cage 154 will interfere with or be impeded by the inner energy absorption surfaces 181. The impediment of the inner energy absorption surfaces 181 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 111 and the propeller shaft 26.

Thus, under normal operating conditions, the ball cage 154 will operate in the normal axial range N of the constant velocity joint 111. In certain crash situations, however, the connecting shaft 144 along with the inner part 152, the ball cage 154 and the torque transmitting balls 156 will be thrust toward the hollow shaft 142 allowing bore energy to be absorb along the outer extended axial range E and or the internal extended axial range IE caused by the impediment of the energy absorption surface 180 upon the outer joint part 150 or inner joint part 152, respectfully. Any number of inner energy absorption surfaces 181 or bore surfaces 182 may be combined with any number of circlips 176, as in Figure 10, in the outer extended axial range E or the inner extended axial range IE of the constant velocity joint 111 to achieve a tuned and controlled energy absorption characteristic. Figure 12 shows a partial view of a constant velocity joint in accordance with an alternative embodiment of the present invention. In this embodiment, there is a tuned energy absorption surface 186, which is a track surface 188. The track surface 188 has a taper 190 and is longitudinally located in the outer extended axial range E of an outer ball track 160 of the outer joint part 150. There can be one or more track surfaces 188 located on anyone of the other outer ball tracks 160. The taper 190 may extend linearly over the outer extended axial range E as shown in the layout view of Figure 13. Alternatively, the track surface may have a variable taper or a stepped taper of increasing or decreasing size. Thus, when the connecting shaft 144 along with the inner joint part 152, the torque transmitting balls 156, and the ball cage 154 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the outer extended axial range E of the joint 111, the torque transmitting balls 156 will interfere with or be impeded by the track surface 188. The impediment of the track surface 188 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 111 and the propeller shaft 26. The track surface 188 can be tuned to achieve different force levels, allowing for the design of a controlled energy absorption profile within the constant velocity joint 111. The tuning may be accomplished by changing the size, the shape, the material, or the location of the track surface 188. The circlips 176 is combined with the track surface 188 as shown in Figure 12 is optional and is not required.

In addition or in the alternative, the track surface 189 having a taper 191 is longitudinally located in the inner extended axial range IE of an inner ball track 161 of the inner joint part 152. There can be one or more track surfaces 189 located on anyone of the other inner ball tracks 161. The taper 191 may extend linearly over the inner extended axial range IE as shown in the layout view of Figure 14. Alternatively, the track surface may have a variable taper or a stepped taper of increasing or decreasing size. Thus, when the connecting shaft 144 along with the inner joint part 152, the torque transmitting balls 156, and the ball cage 154 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the inner extended axial range IE of the joint 111, the torque transmitting balls 156 will interfere with or be impeded by the track surface 189. The impediment of the track surface 189 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 111 and the propeller shaft 26.

Thus, under normal operating conditions, the torque transmitting balls 156 will operate in the normal axial range N of the constant velocity joint 111. In certain crash situations, however, the connecting shaft 144 along with the inner joint part 152, the ball cage 154 and the torque transmitting balls 156 will be thrust toward the hollow shaft 142 allowing track energy to be absorb along the outer extended axial range E and or the internal extended axial range IE caused by the impediment of the track surface 188, 189 upon the outer joint part 150 or inner joint part 152, respectfully.

The one or more track surfaces 188, 189 the one or more circlips 176, the one or more inner energy absorption surfaces 181 and the one or more bore surfaces 182 are combinable to achieve a controlled and tuned energy absorption rate when the constant velocity joint 111 is operated beyond the normal axial range N.

Figure 13 shows a layout view of an outer ball track 160 according to one embodiment of the present invention. The layout view is representative of an outer ball track 160 having a track surface 188 with a taper 190 located in the extended axial range E of a constant velocity joint 111. Figure 14 shows a layout view of an inner ball track

161 according to one embodiment of the present invention. The layout view is representative of an inner ball track 161 having a track surface 189 with a taper 191 located in the inner extended axial range IE of a constant velocity joint 111. Figure 15 shows a half-sectional view of a constant velocity joint in accordance with one embodiment of the present invention in a propeller shaft assembly. The joint 211 is an axially plungeable constant velocity joint of the cross-groove hybrid type. The constant velocity joint 211 comprises an outer joint part 250, an inner joint part 252, a ball cage 254 and more than one torque transmitting ball 256 each held in a cage window 258. The outer joint part 250 comprises a cylindrical open end 266 located proximate to the hollow shaft 242, outer ball tracks 260 which longitudinally extend over the length of the outer joint part 250, having a normal axial range N and an outer extended axial range E. The inner joint part 252 comprises inner ball tracks 261 which longitudinally extend over the length of the inner joint part 252, having a normal axial range N and an inner extended axial range IE. The inner extended axial range IE of the inner joint part 252 is correspondingly positioned in opposite direction, about the normal axial range N, from the outer extended axial range E of the outer joint part 250. Each inner ball track 261 is associated with a corresponding outer ball track 260. Corresponding sets of the outer ball tracks 260 and the inner ball tracks 261 alternate between tracks being axially straight in respect of the axis and tracks forming angles of intersection with respect to an axis. The angles of intersection are identical in size but set in opposite directions and corresponding to the inner ball tracks 261 and the outer ball tracks 260. The length of each inner ball track 261 is commensurate with the length of each outer ball track 260. Alternatively, it can be recognized that the inner ball tracks 261 and the outer ball tracks 260 can have varying lengths, the shorter of which correspondingly commensurate to the angles of intersection of the longer of the two. Thus, the outer joint part 250 and the inner joint part 252 are driveably connected through the torque transmitting balls 256 located in the ball tracks 260, 261; there being one torque transmitting ball 256 for each corresponding pair of alternating sets of ball tracks 260, 261. The torque transmitting balls 256 are positioned and maintained in a constant velocity plane by the ball cage 254, wherein the ball cage 254 is located between the two joint parts 250, 252. The constant velocity joint 211 permits axial movement since the ball cage 254 is not positionably engaged to the inner joint part 252 and the outer joint part 250.

The outer joint part 250 is connected to a hollow shaft 242 that is fixed to the outer joint part by, for example, a friction weld. The hollow shaft 242 may also be flanged and connected to the outer joint part by way of, for example, bolts. Into the inner joint part 252 there is inserted a connecting shaft 244. A plate cap 246 is secured to the outer joint part 250. A convoluted boot 247 seals the plate cap 246 relative to the connecting shaft 244. The other end of the joint 211 at the cylindrical open end 266, i.e., towards the hollow shaft 242, is sealed by a grease cover 248. In addition, the cover 248 may provide some energy absorption should the connecting shaft 244 be thrust beyond the extended axial range E of constant velocity joint 211. The constant velocity joint 211 is designed to operate in it normal axial range N until, however, compression from a crash or an unintended thrust is applied forcing the inner joint part 252, the ball cage 254, and the torque transmitting balls 256 into or through the extended axial ranges E, IE of both joint components.

In this embodiment of the present invention, the joint has a tuned energy absorption surface 274, which is a circlip 276. The circlip 276 is circumferentially located in the outer extended axial range E and coupled to the outer joint part 250. The circlip 276, in this embodiment, is an annular ring, made from a deformable material, preferably metal or plastic, and positionable in the outer joint part 250 so as to reside in the outer ball tracks 260. When the connecting shaft 244 along with the inner joint part 252, the torque transmitting balls 256 and the ball cage 254 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the outer extended axial range E of the joint 211, the torque transmitting balls 256 will interfere with or be impeded by the circlip 276. The impediment of the circlip 276 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 211 and the propeller shaft 26. The circlip 276 can be tuned to achieve different force levels, allowing for design of a controlled energy absorption profile within the constant velocity joint 211. The tuning may be accomplished by changing the size, the shape, the material, or the location of the circlip 276. There may also be more than one circlip 276 located within the outer extended axial range E of the constant velocity joint 211. In addition or alternatively (not shown in Figure 15), the circlip 276 may be circumferentially located in the inner extended axial range IE and coupled to the inner joint part 252. Thus, under normal operating conditions, the torque transmitting balls 25b will operate in the normal axial range N of the constant velocity joint 211. In certain crash situations, however, the connecting shaft 244 along with the inner part 252, the ball cage 254 and the torque transmitting balls 256 will be thrust toward the hollow shaft 242 allowing track and bore energy to be absorb along the outer extended axial range E or the internal extended axial range IE caused by the impediment of the circlip 276 upon the outer joint part 250 or inner joint part 252, respectfully When the joint is positioned in the outer extended axial range E, it is correspondingly positioned in the inner extended axial range IE. It is contemplated that the circlip 276 could be a foreign body, having the same energy absorbing effect as the ring given in this embodiment, residing upon the outer extended axial range E or inner extended axial range IE absorbing plastic energy.

Figure 16 shows a partial view of a constant velocity joint in accordance with alternative embodiments of the present invention. In this embodiment, there is a tuned energy absorption surface 280, which is a bore surface 282. The bore surface 282 is circumferentially located in the extended axial range E, has an inclination Θ and is coupled to the inner bore 264 of the outer joint part 250 between any two outer ball tracks 260 In addition to or in the alternative, the bore surface 282 can have multiple inclinations, stepped inclination, or variable inclination The bore surface 282 ma\ be located between any set of one or more outer ball tracks 260 or upon the entire inner bore surface 264 in the outer extend axial range E. The bore surface 282 may be manufactured by layering, i.e. welding, material upon the inner bore surface 264 of the outer joint part 250 or by undercutting, while machining, the inner bore surface 264. One embodiment contemplates the bore surface 282 to be manufactured from the same material as the outer joint part 250 by reducing the inner bore 264 diameter and forming an inclination Θ in the outer extended axial range E during the machining process However, one in the trade would recognize that the bore surface 282 could be accomplished, among other ways, by tacking, staking, or riveting a material upon the inner bore 264 Thus, when the connecting shaft 244 along with the inner joint part 252, the torque transmitting balls 256, and the ball cage 254 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the outer extended axial range E of the joint 211, the ball cage 254 will interfere with or be impeded by the bore surfaces 282. The impediment of the bore surfaces 282 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 211 and the propeller shaft 26. The bore surfaces 282 can be tuned to achieve different force levels, allowing for design of a controlled energy absorption profile within the constant velocity joint 11. The tuning may be accomplished by changing the size, the shape, the material, or the location of the bore surfaces 282. In addition or alternatively, the energy absorption surface 280 may be an inner energy absorption surface 281 located in the inner extended axial range IE on the outer face 262 of the inner joint part 252. When the connecting shaft 244 along with the inner joint part 252, the torque transmitting balls 256, and the ball cage 254 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the inner extended axial range IE of the joint 211, the ball cage 254 will interfere with or be impeded by the inner energy absorption surfaces 281. The impediment of the inner energy absorption surfaces 281 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 211 and the propeller shaft 26.

Thus, under normal operating conditions, the ball cage 254 will operate in the normal axial range N of the constant velocity joint 211. In certain crash situations, however, the connecting shaft 244 along with the inner part 252, the ball cage 254 and the torque transmitting balls 256 will be thrust toward the hollow shaft 242 allowing bore energy to be absorbed along the outer extended axial range E and or the internal extended axial range IE caused by the impediment of the energy absorption surface 280 upon the outer joint part 250 or inner joint part 252, respectfully.

Any number of inner energy absorption surfaces 281 or bore surfaces 282 may be combined with any number of circlips 276, as in Figure 15, in the outer extended axial range E or the inner extended axial range IE of the constant velocity joint 211 to achieve a tuned and controlled energy absorption characteristic.

Figure 17 shows a partial view of a constant velocity joint in accordance with an alternative embodiment of the present invention. In this embodiment, there is a tuned energy absorption surface 286, which is a track surface 288. The track surface 288 has a taper 290 and is longitudinally located in the outer extended axial range E of an outer ball track 260 of the outer joint part 250. There can be one or more track surfaces 288 located on anyone of the other outer ball tracks 260. The taper 290 may extend linearly over the outer extended axial range E as shown in the layout view of Figure 18. Alternatively, the track surface may have a variable taper or a stepped taper of increasing or decreasing size. Thus, when the connecting shaft 244 along with the inner joint part 252, the torque transmitting balls 256, and the ball cage 254 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the outer extended axial range E of the joint 211, the torque transmitting balls 256 will interfere with or be impeded by the track surface 288. The impediment of the track surface 288 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 211 and the propeller shaft 26. The track surface 288 can be tuned to achieve different force levels, allowing for the design of a controlled energy absorption profile within the constant velocity joint 211. The tuning may be accomplished by changing the size, the shape, the material, or the location of the track surface 288. The circlip 276, combined with the track surface 288 as shown in Figure 17, is optional and is not required.

In addition or in the alternative, the tuned energy absorption surface 286, which is a track surface 289 has a taper 291 and is longitudinally located in the inner extended axial range IE of an inner ball track 261 of the inner joint part 252. There can be one or more track surfaces 289 located on anyone of the other inner ball tracks 261. The taper 291 may extend linearly over the inner extended axial range IE as shown in the layout view of Figure 19. Alternatively, the track surface may have a variable taper or a stepped taper of increasing or decreasing size. Thus, when the connecting shaft 244 along with the inner joint part 252, the torque transmitting balls 256, and the ball cage

254 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the inner extended axial range IE of the joint 211, the torque transmitting balls 256 will interfere with or be impeded by the track surface 289. The impediment of the track surface 289 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 211 and the propeller shaft 26. Thus, under normal operating conditions, the torque transmitting balls 256 will operate in the normal axial range N of the constant velocity joint 211. In certain crash situations, however, the connecting shaft 244 along with the inner joint part 252, the ball cage 254 and the torque transmitting balls 256 will be thrust toward the hollow shaft 242 allowing track energy to be absorb along the outer extended axial range E or the internal extended axial range IE caused by the impediment of the track surface 288, 289 upon the outer joint part 250 or inner joint part 252, respectfully.

The one or more track surfaces 288, 289, the one or more circlips 276, the one or more inner energy absorption surfaces 281, and the one or more bore surfaces 282 are combinable to achieve a controlled and tuned energy absorption rate when the constant velocity joint 211 is operated beyond the normal axial range N. Figure 18 shows a layout view of an outer ball track according to alternative embodiments of the present invention. The layout view is representative of the outer joint part 250 unrolled about its axis having a plurality of alternating outer ball tracks 260 extending in the axial direction over a normal axial range N and an extended axial range E. The energy absorption surfaces 286, 280, 274 are all within the extended axial range E of the outer joint part 250. One embodiment of the energy absorption surface 86, which is a track surface 288, is shown having a taper 290. Another alternative embodiment is by welding, tacking or riveting a material in the outer ball track 260 to form an energy absorption surface 286, which is a track surface 292. Alternatively, layering a weld bead 283 or riveting a material 284 upon the inner bore 264 forms an energy absorption surface 280 on the outer joint part 250. Figure 19 shows a layout view of an inner ball track according to alternative embodiments of the present invention. The layout view is representative of the inner joint part 252 unrolled about its axis having a plurality of alternating inner ball tracks

261 extending in the axial direction over a normal axial range N and an inner extended axial range IE. The energy absorption surfaces 286, 280, 274 are all within the inner extended axial range IE of the inner joint part 252. One embodiment of the energy absorption surface 286, which is a track surface 289, is shown having a taper 291. Another alternative embodiment is by welding, tacking or riveting a material in the outer ball track 261 to form an energy absorption surface 286, which is a track surface 293. Alternatively, layering a weld bead 285 upon the inner bore 264 forms an energy absorption surface 280 on the outer joint part 250.

Additionally, Figures 18 and 19 correspondingly show the location of the torque transmitting balls 256 for a particular articulation and axial displacement of the joint 211. Figure 20 shows a half-sectional view of a constant velocity joint 311 in accordance with one embodiment of the present invention in a propeller shaft assembly The joint 311 is an axially plungeable constant velocity joint of the double offset type. The constant velocity joint 311 comprises an outer joint part 350, an inner joint part 352, a ball cage 354 and more than one torque transmitting balls 356 each held in a cage window 358. The outer joint part 350 comprises an inner bore 364, a cylindrical open end 366 located at the end of the inner bore 364 and proximate to the hollow shaft 342, more than one outer ball tracks 360 which longitudinally extend over the length of the outer joint part 350, a normal axial range N and an extended axial range E. The inner joint part 352 comprises a convex guiding face 370, and more than one inner ball tracks 361 which longitudinally extend over the length of the inner joint part 352. Each inner ball track 61 has a corresponding outer ball track 360. Thus, the outer joint part 350 and the inner joint part 352 are driveably connected through the torque transmitting balls 356 located in axially straight ball tracks 360, 361; there being one torque transmitting ball 356 for each corresponding pair of ball tracks 360, 361 The torque transmitting balls 356 are positioned and maintained in a constant velocity plane by the ball cage 354. The ball cage 354 is located between the two joint parts 350, 352 and has an axially offset outer spherical face 362 and an inner concave guiding face 363 that defines a constant velocity plane. The constant velocity joint 311 permits axial movement since the convex guiding face 370 of the inner joint part 352 positionably engages the inner concave guiding face 363 of the ball cage 354 and the inner bore 364 of the outer joint part 350 guides the outer spherical face 362 of the ball cage 354. The outer joint part 350 is connected to a hollow shaft 342 that is fixed to the outer joint part by, for example, a friction weld. The hollow shaft 342 may also be flanged and connected to the outer joint part by way of, for example, bolts.

Into the inner joint part 352 there is inserted a connecting shaft 344. A plate cap 346 is secured to the outer joint part 350. A convoluted boot 347 seals the plate cap 346 relative to the connecting shaft 344. The other end of the joint 311 at the cylindrical open end 366, i.e., towards the hollow shaft 342, is sealed by a grease cover 348. In addition, the cover 348 may provide some energy absorption should the connecting shaft 344 be thrust beyond the extended axial range E of constant velocity joint 311. The constant velocity joint 311 is designed to operate in its normal axial range N until, however, compression from a crash or an unintended thrust is applied forcing the inner joint part 352, the ball cage 354, and the torque transmitting balls 356 into or through the extended axial range E.

In this embodiment of the present invention there is a tuned energy absorption surface 374, which is a circlip 376. The circlip 376 is circumferentially located in the extended axial range E and coupled to the inside surface 351 of the outer joint part 350. The circlip 376, in this embodiment, is an annular ring, made from a deformable material, preferably metal or plastic, and positionable in the outer joint part 350 so as to reside in the outer ball tracts 360. When the connecting shaft 344 along with the inner joint part 352, the torque transmitting balls 356 and the ball cage 354 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the extended axial range E of the joint 311, the torque transmitting balls 356 will interfere with or be impeded by the circlip 376. The impediment of the circlip 376 causes an increase in the thrust required for axial motion, thereby allowing energy to be absorbed by the constant velocity joint 311 and the propeller shaft 326. The circlip 376 can be a tuned so as to achieve different force levels, allowing for the design of a controlled energy absorption profile within the constant velocity joint 311. The tuning can be accomplished by changing the size, the shape, the material, or the location of the circlip 376. There may be more than one circlip 376, although not shown, located within the extended axial range E of the constant velocity joint 311. l nus, under normal operating conditions, the torque transmitting balls 356 will operate in the normal axial range N of the constant velocity joint 311. In certain crash situations, however, the connecting shaft 344 along with the inner part 352, the ball cage 354 and the torque transmitting balls 356 will be thrust toward the hollow shaft 342 allowing track and bore energy to be absorbed along the extended axial range E caused by the impediment of the circlip 376 upon the inside surface 351 of the outer joint part 350. It is contemplated that the circlip 376 could be a foreign body residing upon the extended axial range E absorbing plastic energy.

Figure 21 shows a partial view of a constant velocity joint in accordance with alternative embodiment of the present invention. In this embodiment, there is a tuned energy absorption surface 380, which is a bore surface 382. The bore surface 382 is circumferentially located in the extended axial range E, has an inclination Θ and is coupled to the inner bore 364 of the outer joint part 350 between any two adjacent outer ball tracks 360. In addition to or as an alternative, the bore surface 382 can have multiple inclinations, stepped inclination, or variable inclination. The bore surface 382 may be located between any set of one or more outer ball tracks 360 or upon the entire inner bore surface 364 in the extend axial range E. The bore surface 382 may be manufactured by layering, i.e. welding, material upon the inner bore surface 364 or by undercutting, while machining, the inner bore surface 364. One embodiment contemplates the bore surface 382 to be manufactured from the same material as the outer joint part 350 by reducing the inner bore 364 diameter forming an inclination Θ in the extended axial range E during the machining process. However, one in the trade would recognize that the bore surface 382 could be accomplished, among other ways, by tacking, staking, or riveting a material upon the inner bore 364. Thus, when the connecting shaft 344 along with the inner joint part 352, the torque transmitting balls

356, and the ball cage 354 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the extended axial range E of the joint 311, the ball cage 354 will interfere with or be impeded by the bore surfaces 382. The impediment of the bore surfaces 382 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 311 and the propeller shaft 26. The bore surfaces 382 can be tuned, so as to achieve different force levels, allowing for design of a controlled energy absorption profile within the constant velocity joint 311. The tuning may be accomplished by changing the size, the shape, the material, or the location of the bore surfaces 82. Any number of bore surfaces 382 may be combined with any number of circlips 376, as in Figure 20, in the extended axial range E of the constant velocity joint 311 to achieve a tuned and controllable energy absorption rate.

Thus, under normal operating conditions, the ball cage 354 will operate in the normal axial range N of the constant velocity joint 311. In certain crash situations, however, the connecting shaft 344 along with the inner part 352, the ball cage 354 and the torque transmitting balls 356 will be thrust toward the hollow shaft 342 allowing bore energy to be absorbed along the extended axial range E caused by the impediment of the bore surface 382 upon the inside surface 351 of the outer joint part 350.

Figure 22 shows a partial view of a constant velocity joint in accordance with alternative embodiment of the present invention. In this embodiment, there is a tuned energy absorption surface 386, which is a track surface 388. The track surface 388 having a taper 390 and is longitudinally located in the extended axial range E of an outer ball track 360 of the outer joint part 350. There can be one or more track surfaces 388 located on anyone of the other outer ball tracks 360. The taper 390 may extend linearly over the extended axial range E as shown in the layout view of Figure 23. Alternatively, not shown, the track surface may have a variable taper or a step taper of increasing or decreasing size. Thus, when the connecting shaft 344 along with the inner joint part 352, the torque transmitting balls 356, and the ball cage 354 are thrust, as a result of an unintended force, such as a crash, beyond the normal axial range N and into the extended axial range E of the joint 311, the torque transmitting balls 356 will interfere with or be impeded by the track surface 388. The impediment of the track surface 388 causes an increase in the thrust required for axial motion allowing energy to be absorbed by the constant velocity joint 311 and the propeller shaft 26. The track surface 388 can be tuned to achieve different force levels, allowing for the design of a controlled energy absorption profile within the constant velocity joint 311. The tuning may be accomplished by changing the size, the shape, the material, or the location of the^" track surface 388. The circlip 376 is combined with the track surface 388 as shown in Figure 22, but is not required. Thus, under normal operating conditions, the torque transmitting balls 356 will operate in the normal axial range N of the constant velocity joint 311. In certain crash situations, however, the connecting shaft 344 along with the inner joint part 352, the ball cage 354 and the torque transmitting balls 356 will be thrust toward the hollow shaft 342 allowing track energy to be absorb along the extended axial range E caused by the impediment of the track surface 388 upon the inside surface 351 of the outer joint part 350. The one or more track surfaces 388, the one or more circlips 376, and the one or more bore surfaces 382 are combinable to achieve a controlled and tuned energy absorption rate when the constant velocity joint 311 is operated beyond its normal axial range N.

Figure 23 shows a layout view of an outer ball track 360 according to one embodiment of the present invention. The layout view is representative of an outer ball track 360 having a track surface 388 with a taper 390 located in the extended axial range E of a constant velocity joint 311.

From the foregoing, it can be seen that there has been brought to the art a new and improved crash-worthy constant velocity joint. While the invention has been described in connection with one or more embodiments, it should be understood that the invention is not limited to those embodiments On the contrary, the invention covers all alternatives, modifications, and equivalents as may be included within the spirit and scope of the appended claims.

Claims

What Is Claimed Is:

1. An energy absorbing plunging constant velocity joint comprising: an outer joint part and an outer extended axial range; an inner joint part disposed within said outer joint part; a plurality of torque transmitting mechanisms guided between said outer joint part and said inner joint part within a normal axial range; and one or more energy absorption surfaces distal to the normal axial range and located in the extended axial range upon said outer joint part, wherein the energy absorption surface on the outer joint part interferes with said inner joint part or at least one of said plurality of torque transmitting mechanism when said outer joint part is operated beyond said normal axial range.

2. The joint according to claim 1, wherein one of the energy absorption surfaces is a circlip.

3. The joint according to claim 2, wherein the circlip is made from a deformable material.

4. The joint according to claim 3, wherein the deformable material is metal.

5. The joint according to claim 3, wherein the deformable material is plastic.

6. The joint according to claim 2, wherein the circlip is a ring.

7. The joint according to claim 1, wherein one of the energy absorption surfaces is a bottom surface located on a longitudinally extending track of said outer joint part.

8. The joint according to claim 7, wherein the bottom surface has one or more inclination, a stepped inclination or a variable inclination.

9. The joint according to claim 7, wherein the bottom surface is made from the same material piece as the outer joint part.

10. The joint according to claim 1, wherein one of the energy absorption surfaces is a bore surface.

11. The joint according to claim 10, wherein the bore surface has one or more inclination, a stepped inclination or a variable inclination.

12. The joint according to claim 10, wherein the bore surface is made from the same material piece as the outer joint part.

13. The joint according to claim 1, wherein one of the energy absorption surfaces is a track surface.

14. The joint according to claim 13, wherein the track surface has one or more tapers or a stepped taper.

15. The joint according to claim 14, wherein the track surface is made from the same material piece as the outer joint part.

16. The joint according to claim 1, wherein the outer joint part further comprises a cylindrical open end located adjacent the extended axial range and distal to the normal axial range of the outer joint part and a grease cover sealingly attached to the cylindrical open end.

17. The joint according to claim 16, wherein the grease cover is displaceable when the joint has axial travel beyond the extended axial range.

18. The joint according to claim 1, wherein one or more of the energy absorption surfaces is machined, forged, or staked into the outer joint part in the extended axial range.

19. A propeller shaft assembly for a vehicle having an energy absorbing plunging constant velocity joint comprising: an outer joint part and an outer extended axial range; an inner joint part disposed within said outer joint part; a plurality of torque transmitting mechanisms guided between said outer joint part and said inner joint part within a normal axial range; and one or more energy absorption surfaces distal to the normal axial range and located in the extended axial range upon said outer joint part, wherein the energy absorption surface on the outer joint part interferes with said inner joint part or at least one of said plurality of torque transmitting mechanism when said outer joint part is operated beyond said normal axial range; a hollow shaft connected to said outer joint part; and a connecting shaft connected to said inner joint part, wherein the hollow shaft contains the connecting shaft, the inner joint part, and the rollers when said joint is operated beyond the extended axial range.

20. The joint according to claim 19, wherein the outer joint part further comprises a cylindrical open end located adjacent the extended axial range and distal to the normal axial range of the outer joint part and a grease cover sealingly attached to the cylindrical open end, wherein the grease cover is displaceable when the joint has axial travel beyond the extended axial range.