ROLL RESTRICTOR SYSTEM FOR AN AUTOMOTIVE POWERTRAIN

Abstract

An aspect of the invention provides a roll restrictor system for an automotive powertrain, comprising: a torque roll restrictor bracket configured for attachment to the automotive powertrain; wherein attachment is mediated by a bushing; wherein the bushing is provided within a bearing which facilitates rotation of the bushing within the torque roll restrictor bracket.

Claims

1. A roll restrictor system for an automotive powertrain, comprising: a torque roll restrictor bracket configured for attachment to the automotive powertrain; wherein the attachment is mediated by a bushing; wherein the bushing is provided within a bearing which facilitates rotation of the bushing within the torque roll restrictor bracket.

2. The roll restrictor system according to claim 1, wherein the bushing is a voided bushing.

3. The roll restrictor system according to claim 2, wherein the voided bushing comprises at least two arms which support the voided bushing in an opening through the torque roll restrictor bracket.

4. The roll restrictor system according to claim 3, wherein the voided bushing comprises four arms.

5. The roll restrictor system according to claim 1, wherein the bearing is a ball bearing.

6. The roll restrictor system according to claim 5, wherein the ball bearing is a self-aligning ball bearing.

7. The roll restrictor system according to claim 1, wherein the bearing is a roller bearing.

8. The roll restrictor system according to claim 1, wherein the roll restrictor bracket is attached to the powertrain in at least two places and to a vehicle chassis or sub-frame in at least one place.

9. The roll restrictor system according to claim 1, wherein the bearing has an outer surface that is coated with a vibration absorbing material.

10. The roll restrictor system according to claim 9, wherein the vibration absorbing material is rubber.

11. The roll restrictor system according to claim 4, wherein the bearing is a ball bearing.

12. The roll restrictor system according to claim 3, wherein the roll restrictor bracket is attached to the powertrain in at least two places and to a vehicle chassis or sub-frame in at least one place.

13. The roll restrictor system according to claim 4, wherein the roll restrictor bracket is attached to the powertrain in at least two places and to a vehicle chassis or sub-frame in at least one place.

14. The roll restrictor system according to claim 3, wherein the bearing has an outer surface that is coated with a vibration absorbing material.

15. The roll restrictor system according to claim 5, wherein the bearing has an outer surface that is coated with a vibration absorbing material.

16. The roll restrictor system according to claim 7, wherein the bearing has an outer surface that is coated with a vibration absorbing material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The disclosure will now be further and more particularly described, by way of example only, and with reference to the accompanying drawings, in which:

[0019] FIG. 1 illustrates a prior art roll restriction system for an automotive powertrain;

[0020] FIG. 2 illustrates a voided bushing for use within a roll restriction system for an automotive powertrain;

[0021] FIG. 3 illustrates a ball bearing housing a voided bushing;

[0022] FIG. 4 illustrates a self-aligning ball bearing housing a voided bushing;

[0023] FIG. 5 illustrates a roller bearing housing a voided bushing;

[0024] FIG. 6 illustrates a bearing for receiving a bushing and having an outer rubber coating.

DETAILED DESCRIPTION

[0025] As shown in FIG. 1, an automotive powertrain 10 includes a prior art roll restriction system 12 comprising a core 14 that is attached to a vehicle sub-frame of a vehicle 2, e.g. via a link bolt 16; and a housing 18 that is in turn connected to a mounting bracket 20 via a bolt 22 through a bushing 24. The mounting bracket 20 is mounted to the transmission clutch housing 26 via one or more further bolts 28. The vehicle 2 may be a wheeled motor vehicle for travel on a road.

[0026] FIG. 2 illustrates one solution that results in reduced translational and rotational stiffness of the roll restriction system 10. The bushing 24 has a key shaped aperture 30 therethrough for receiving a bolt 22. The bushing 24 is voided such that it is supported in the mounting bracket 20 by two diametrically opposed rubber arms 32 instead of a solid rubber bush.

[0027] The bushing 24 is either bonded directly to the mounting bracket 20, or to a sleeve (not shown) which is pressed into the mounting bracket 20. As the powertrain 10 rotates it will induce rotation of the bushing 24 relative to the mounting bracket 20. This creates greater strain within a voided bushing 24 as compared to a solid bushing due to the reduced rubber and stiffness of the voided bushing 24. As temperature of the voided bushing 24 rises the rubber softens thus enhancing the strain within the voided bushing further.

[0028] Bonding the bushing 24 into a sleeve (not shown) and pressing the sleeve into the mounting bracket 20 results in sleeve wear due to rotation of the sleeve relative to the mounting bracket 20 and can result in axial movement of the bushing 24 relative to the mounting bracket 20 under cornering load.

[0029] A solution to increased strain exhibited by a voided bushing is found in FIGS. 3, 4 and 5. The voided bushing 24 is pressed directly into a bearing 34 (FIG. 3) or self-aligning ball-bearing 36 (FIG. 4) or roller bearing 38 (FIG. 5). The voided bushing 24 is permitted to rotate freely relative to the mounting bracket 20 while being held in place by the bearing 34, 36, 38. The bearing, in some embodiments, is a self-aligning ball bearing 36, as illustrated in FIG. 4 which permits certain rotation of the ball ring in both a first rotational orientation and a second rotational orientation relative to the ball bearing race.

[0030] In some embodiments, the voided bushing 24 is first pressed into a sleeve 40. The sleeve 40 is then pressed into the bearing 34, 36, 38.

[0031] In some embodiments the bearing 42, as illustrated in FIG. 6, is provided with an outer surface coated with a vibration absorbent material 44 such as rubber. FIG. 6 does not show a bushing pressed into the bearing 42 but it will be appreciated that either a voided bushing 24 or solid bushing could be used to mediate attachment of the mounting bracket 20 to the automotive powertrain 10.

[0032] FIGS. 1-6 show example configurations with relative positioning of the various components. If shown directly contacting each other, or directly coupled, then such elements may be referred to as directly contacting or directly coupled, respectively, at least in one example. Similarly, elements shown contiguous or adjacent to one another may be contiguous or adjacent to each other, respectively, at least in one example. As an example, components laying in face-sharing contact with each other may be referred to as in face-sharing contact. As another example, elements positioned apart from each other with only a space there-between and no other components may be referred to as such, in at least one example. As yet another example, elements shown above/below one another, at opposite sides to one another, or to the left/right of one another may be referred to as such, relative to one another. Further, as shown in the figures, a topmost element or point of element may be referred to as a top of the component and a bottommost element or point of the element may be referred to as a bottom of the component, in at least one example. As used herein, top/bottom, upper/lower, above/below, may be relative to a vertical axis of the figures and used to describe positioning of elements of the figures relative to one another. As such, elements shown above other elements are positioned vertically above the other elements, in one example. As yet another example, shapes of the elements depicted within the figures may be referred to as having those shapes (e.g., such as being circular, straight, planar, curved, rounded, chamfered, angled, or the like). Further, elements shown intersecting one another may be referred to as intersecting elements or intersecting one another, in at least one example. Further still, an element shown within another element or shown outside of another element may be referred as such, in one example.

[0033] Spatially relative terms, such as inner, outer, beneath, below, lower, above, upper, and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as below or beneath other elements or features would then be oriented above the other elements or features. Thus, the example term below can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0034] It will further be appreciated by those skilled in the art that although the invention has been described by way of example with reference to several embodiments it is not limited to the disclosed embodiments and that alternative embodiments could be constructed without departing from the scope of the invention as defined in the appended claims. In particular, reference to a voided bushing throughout the description is not intended to be limiting and those skilled in the art will appreciate that a solid bushing could be used in some applications of the invention.