Driveline for powersports vehicle

Abstract

A Powersports vehicle is disclosed which includes a frame, ground engaging members supporting the frame, comprising at least two front wheel, and a power source for driving the front wheels. A front drive is coupled to the power source and to the front wheels, the front drive being coupled to the frame through isolation mounts to reduce vibration of the front drive through the frame.

Claims

1. A vehicle, comprising: a frame; ground engaging members supporting the frame, comprising at least two wheels; a power source; a drive operably coupled to the power source at a drive input and to the wheels at a drive output, the drive being coupled to the frame through at least one isolation mount comprised of a vibration-absorbing material; wherein the at least one isolation mount includes a first portion and a second portion abutting the first portion, and the first portion having a hardness greater than a hardness of the second portion; and wherein the second portion includes a pair of isolation grommets and the first portion includes a sleeve extending between the pair of isolation grommets; and a diameter of the isolation grommets is greater than a diameter of the sleeve.

2. The vehicle of claim 1, wherein the drive includes at least one collar, an inner diameter of the at least one collar being less than the diameter of a first portion of the isolation grommets.

3. The vehicle of claim 2, wherein the first portion of the isolation grommets is positioned outward of the at least one collar.

4. The vehicle of claim 3, wherein a second portion of each of the pair of isolation grommets is inserted into the at least one collar.

5. The vehicle of claim 1, wherein a composition of the first portion is consistent throughout the first portion.

6. The vehicle of claim 1, wherein at least one of the first portion and the second portion is comprised of a rubber substance.

7. The vehicle of claim 1, wherein the at least one isolation mount is configured for multiple rates of resistance in relation to deflection of the at least one isolation mount.

8. A vehicle, comprising: a frame; ground engaging members supporting the frame, comprising at least two wheels; a power source; a drive coupled to the power source at a drive input and to the wheels at a drive output, the drive being coupled to the frame through at least one isolation mount comprised of a vibration-absorbing material; wherein the at least one isolation mount is configured for multiple rates of resistance in relation to deflection of the at least one isolation mount; and wherein the at least one isolation mount is directly coupled to the drive.

9. The vehicle of claim 8, wherein the at least one isolation mount is configured for multiple rates of resistance by comprising a first portion of a material having a first hardness and a second portion of a material having of a second hardness, the first hardness being greater than the second hardness.

10. The vehicle of claim 8, wherein at least a portion of the at least one isolation mount is comprised of a rubber substance.

11. The vehicle of claim 8, wherein the at least one isolation mount extends at least a width of the drive.

12. A vehicle, comprising: a frame; ground engaging members supporting the frame, comprising at least two wheels; a power source; a drive operably coupled to the power source at a drive input and to the wheels at a drive output, the drive being coupled to the frame through at least one isolation mount, the at least one isolation mount having a first portion and second portion; wherein the drive includes at least one collar configured to contact the first portion of the at least one isolation mount at a first compression force and configured to contact the second portion of the at least one isolation mount at a second compression force.

13. The vehicle of claim 12, wherein the first portion of the at least one isolation mount has a durometer value less than that of the second portion.

14. The vehicle of claim 13, wherein a diameter of the first portion when in a non-contact state with the at least one collar is greater than a diameter of the first portion when in a contact state with the at least one collar.

15. The vehicle of claim 12, wherein the first portion is adjacent the second portion within the at least one collar.

16. The vehicle of claim 12, wherein the first portion of the at least one isolation mount comprises a pair of isolation grommets configured to be at least partially received by the at least one collar, and the second portion of the at least one isolation mount comprises a sleeve extending between each of the pair of isolation grommets.

17. A method of reducing a transfer of vibrational forces at a front drive of a vehicle, comprising: providing a front drive having a mounting portion having an inner diameter; providing an isolation mount configured to cooperate with the mounting portion and comprising a first portion and a second portion, the first portion having an uncompressed diameter greater than the inner diameter of the mounting portion; receiving, at least partially, the first portion within the mounting portion by compressing the first portion such that the first portion has a compressed diameter less than or equal to the inner diameter of the mounting portion and less than the uncompressed diameter; compressing the first portion at a first reaction load; and contacting the second portion at a second reaction load greater than the first reaction load.

18. The method of claim 17, wherein the first portion has a durometer value less than that of the second portion.

19. The method of claim 17, wherein receiving, at least partially, the first portion within the mounting portion includes pre-stressing the first portion upon receipt of the first portion within the mounting portion.

20. The method of claim 17, wherein compressing the first portion at the first reaction load includes pre-stressing the first portion upon receipt of the first portion within the mounting portion.

21. The method of claim 17, wherein compressing the first portion includes resisting the first reaction load at a first rate of resistance and contacting the second portion includes resisting the second reaction load at a second rate of resistance.

22. A vehicle, comprising: a frame; a plurality of ground engaging members supporting the frame, comprising at least two wheels; a power source; a drive operably coupled to the power source at a drive input and to the wheels at a drive output, the drive being coupled to the frame through at least one isolation mount including a vibration-absorbing material; wherein the at least one isolation mount includes a first portion and a second portion abutting the first portion, and the first portion having a hardness greater than a hardness of the second portion, wherein the second portion includes a first isolation grommet with a first inner axial end face and a second isolation grommet with a second inner axial end face, and the first portion includes a sleeve extending directly between the first inner axial end face and the second inner axial end face.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a front left perspective view of a portion of the vehicle frame showing the front drive mounted in the frame;

(2) FIG. 2 is a left side view of the frame and front drive of FIG. 1;

(3) FIG. 3A is an enlarged left front perspective view of a portion of the frame shown in FIG. 1;

(4) FIG. 3B is an enlarged right rear perspective view of a portion of the frame shown in FIG. 1;

(5) FIG. 4 is an exploded view of the front drive and mounting hardware;

(6) FIG. 5 is a left side view of the front drive;

(7) FIG. 6 is a front view of the front drive;

(8) FIG. 7 is a cross-sectional view through lines 7-7 of FIG. 2;

(9) FIG. 8 shows a rear view of the mounting hardware;

(10) FIG. 9 is a view similar to that of FIG. 8 showing the right cast leg removed;

(11) FIG. 10 is a view similar to that of FIG. 8 showing the power steering rack in a mounted condition; and

(12) FIG. 11 is an alternate mount from that shown in FIG. 8.

DETAILED DESCRIPTION OF THE DRAWINGS

(13) With reference first to FIGS. 1 and 2, a vehicle front end is shown at 2 having a frame front end 4, a front drive 6 coupled to the frame 4 by way of a front drive mount 8. A prop shaft 10 extends forwardly from a powertrain (not shown) to supply power to the front drive 6 in order to drive wheels through outputs at 12. Half-shafts (not shown) would be coupled to the outputs 12 and then to the wheels, as is known. Front drive 6, may be a differential but need not be. While the embodiment shown is in the context of a front drive, the present disclosure is equally applicable to a rear drive for a vehicle.

(14) With reference now to FIGS. 3A and 3B, frame front end 4 will be described in greater detail. As shown, front end 4 includes main frame tubes 20 having longitudinally extending sections at 22 which neck down at 24 defining front lower frame tubes 26. A first channel 28 extends transversely of tubes 26 and includes apertures at 28a, while a second channel 30 extends transversely of tubes 26 and includes apertures 30a. It should be appreciated that channels 28 and 30 receive a lower A-arm of the suspension system having an inner end coupled to apertures 28a and 30a. Mounting brackets 32 (32L and 32R) extend from tubes 26 intermediate channels 28 and 30 and include mounting apertures 32a. Another channel 34 is defined between plates 36 and 38 and couple frame tubes 40 thereto.

(15) Frame tubes 40 include upright portions 42 and rearwardly extending portions 44. Rear upright tubes 50 extend upwardly from frame tubes 26 and include a further transverse channel at 52 providing another mount for an alignment arm at opposite ends thereof. Frame tubes 50 include a first mounting bracket at 56 having a mounting aperture at 56a, and a second mounting bracket 58 having a mounting aperture at 58a. A front mounting bracket 60 is coupled between the upright frame tubes 42 and defines a front mounting plate 62 for a winch, rear mounting plate 64 for a radiator and mounting brackets 66 (FIG. 3B) for the front drive mount 8 as described herein. Brackets 66 include mounting apertures at 66a.

(16) With reference now to FIG. 4, front drive mount 8 is shown having a top wall at 70, side walls at 72 and rear bracket walls at 74. Side walls 72 include mounting apertures 76 and embossed mounting areas 78 having apertures 80 therethrough. As shown, fasteners 82 are receivable through openings 76 and 80 to receive washers 84 and fasteners 86 as described herein. Rear bracket wall 74 further includes mounting apertures at 90 for receiving fasteners 92 as described herein.

(17) With reference still to FIG. 4, mounting posts 100, 102 are shown where mounting post 100 includes an upper post portion 104, an intermediate and arcuately shaped portion 106 and a lower post portion 108. Upper post portion 104 is notched at 110 and includes an aperture at 112 and lower post portion 108 is notched at 114 and includes a mounting aperture 115 (FIG. 8). Mounting apertures 116 are provided through the mounting post 100. Mounting post 102 includes an upper post portion 120, an intermediate and arcuate shaped portion 122 and a lower post portion 124. Upper post portion 120 is notched at 126 and includes a mounting aperture at 128. Lower post portion 124 is notched at 130 and includes a mounting aperture 131 (FIG. 8). Mounting apertures 132 are positioned through post 102. Post 100 includes a lower mounting surface at 140 and an upper mounting surface at 142. Post 102 includes a lower mounting surface 144 and an upper mounting surface at 146.

(18) Although not part of the front drive mount, mounting plate 150 is coupled between the mount 8 and the posts 100, 102 and provides a mounting structure for a power steering gear as described herein. Mounting plate 150 includes mounting apertures at 152, and indentation at 154 for receiving a portion of the power steering unit, mounting apertures 156 and mounting apertures 158. With reference now to FIGS. 4-6, front drive 6 will be described in greater detail. It should be understood that the front drive mount of the present disclosure is also useable without power steering.

(19) With reference first to FIG. 5, front drive 6 includes a housing 160 which houses a ring gear 162 shown in phantom which is driven by an input shaft 164 which couples to the prop shaft 10 through a universal joint 166 (FIG. 2). Front drive 6 further includes a front collar 170 adjacent a front end of the housing and a rear collar 172 adjacent a rear housing 160. As shown, both collars 170 and 172 are positioned towards an upper edge of housing 160 so as to suspend front drive 6 when mounted. Collar 170 has an inside diameter 174 (FIG. 4) and collar 172 has an inside diameter 176 (FIG. 4). Collars 170 and 172 are also positioned towards extreme front and rear positions of the housing as shown.

(20) Namely, a forwardmost edge of the collar is shown at 180 which is forward of a forwardmost edge 182 of ring gear 162. Forward edge 180 is positioned forward of forwardmost edge 182 of ring gear 162 by a dimension of D1 as shown in FIG. 5. In a like manner, collar 172 has a rearwardmost position at 186 which is rearward of a rearwardmost edge of ring gear 162 as shown at 188. Rearwardmost position 186 of collar 172 is positioned rearward of ring gear 162 by a dimension of D2 as shown in FIG. 5. As also shown in FIG. 5, a top of the ring gear 162 has an extreme upper position shown at 190 whereas a top of the collar 170 is shown at 192 where the top 192 is spaced from a top 190 of the ring gear 162 by a distance of D3. Preferably, a line drawn between centers of the collars 170, 172 does not intersect a center of the output 12.

(21) As shown in FIG. 5, the distance from a center of output 12 to a center of collar 170 is shown at R.sub.1. As also shown in FIG. 5, the distance from a center of output 12 to a center of collar 172 is shown at R.sub.2. In the embodiment shown, R.sub.1 and R.sub.2=117.8 mm. The radius of the ring gear 162 is 85.3 mm such that the ratio R.sub.1/Ring Gear Radius is 1.38. Also the arc defined between the radius lines for R.sub.1 and R.sub.2 is shown at θ, where θ=83.6°. The acceptable range for θ is between 70° and 170°, preferably between 75° and 120°; and more preferably between 80° and 100°. It is also more preferable to have the collars 170, 172 positioned at the top of the housing, such that the packaging the drive itself may limit the angle; that is, as the angle increases so does the length of the housing 160. While the collars 170, 172 are shown at the top of the housing, it should be understood that the collars 170, 172 could be positioned in a like position at the bottom of housing 160.

(22) With reference now to FIG. 6, the extreme lateral positions of the collar 170 are shown at 200 and 202 and extend the beyond the lateral width of the housing 160. As shown in FIG. 6, extreme lateral position 202 is spaced from an outer edge of output 12 by a distance of D.sub.4, where D.sub.4=30.58 mm. As also shown in FIG. 6, extreme lateral position 200 is spaced from an outer edge of left output 12 by a distance of D.sub.5, where D.sub.5=30.58 mm.

(23) With reference again to FIG. 4, isolation mounts 210 are positioned in each of the collars 170, 172. As shown, each isolation mount 210 is comprised of two isolation grommets 220, a single sleeve 230 and a tube 234. Grommets 220 are provided positioned in opposite ends of each of the collars 170 and 172. As shown in FIGS. 4 and 7, each of the isolation grommets 220 includes a head portion 222 having an aperture 224 extending through the entirety of the isolation grommet 220. The isolation grommets 220 also include a body portion 226 which press against inside diameters 174, 176 of the collars 170, 172 (see FIG. 7). With reference to FIGS. 4 and 7, the sleeve 230 is also provided having an aperture at 232. As shown in FIG. 7, the isolation mounts 220 are profiled such that the head portions 222 abut the ends of the collars 170, 172 whereas ends of the isolation grommets 220 abut the sleeve 230 in the collar.

(24) The tube 234 is profiled to fit within the inner diameter 224 of grommets 220 and within the inner diameter 232 of sleeve 230. The tube 234 has a length such that it fits within surfaces 66 as shown best in FIG. 7. At the rear connection (through collar 172, the tube 234 would extend between the embossments 78). Tube 234 is constructed from a rigid material such as a metal such as aluminum or steel, such that the fasteners 82, 86 do not crush the grommets 220 when torqued. It should be appreciated that the isolation mounts 210 could be provided in any configuration, for example as a plurality of components or as integrated components.

(25) To mount the front drive 6 to the front frame portion 4, posts 100, 102 are first mounted to the front frame portion 4. As shown in FIG. 1, post 100 is shown positioned between bracket 32L and bracket 56 with aperture 112 (FIG. 4) aligned with aperture 56a (FIG. 3A) and with aperture 115 (FIG. 8) aligned with aperture 32a (FIG. 3A). Fasteners would couple the post 100 to the front frame portion 4. In a like manner, post 102 would be positioned on bracket 32R (FIG. 3B) and bracket 58 (FIG. 3A) with aperture 128 aligned with aperture 58a (FIG. 3A) and with aperture 131 aligned with aperture 32a. Again fasteners would couple post 102 to the front frame portion 4. Mount 8 and plate 150 (FIG. 4) are then aligned such that apertures 90 on the right hand side of mount 8 are aligned with apertures 152 and with apertures 132 of post 102.

(26) Fasteners 92 are then positioned through apertures 90 and 152 and are threadably engaged in apertures 132 of post 102. This positions the mount 8 and the post 150 in the position of FIG. 8 whereby plate 150 is suspended between posts 100 and 102. Front drive 6 may then be mounted in the mount 8 by positioning a tube 234 within each sleeve, and positioning the sleeve into each collar 170, 170. The isolation mounts 220 are then positioned in each end of the collars 170 and 172. The tubes 234 are then aligned with the apertures 76 and 80 in the mount 8. Studs such as 82 may then be positioned through apertures 76 and 80, through the sleeve 230 and then through each of the isolation mounts 220. Fasteners 84 and 86 may be connected to the studs 82. The coupled positioned of the front drive 6 to the mount 8 is shown in cross-section in FIG. 7.

(27) With reference now to FIG. 10, the steering gear 250 may now be coupled to the backside of plate 150 whereby the boots 252 and 254 of the steering gear 250 nest within the arcuate shaped portions 106, 122 respectively.

(28) By positioning the collars at extreme locations relative to the front drive 6, the reaction forces based upon the torque transmitted through the housing are minimized at the mounting locations. By positioning the isolation mounts within the collars, the vibration associated with the front drive 6 is reduced to the frame and resultantly to the driver through vibration. More particularly, torque along two axes is applied to the front drive 6 which causes reaction forces. Namely, a first torque is applied to the front drive as shown at 300 (FIG. 5) through the shaft 164, and a second torque is shown at 302 through couplings 12.

(29) Also, as shown in FIG. 7, the diameter of the body portion 226 of the isolation grommets 220 is greater than the diameter of the sleeve 230. The diameter of the body portion 226 of the isolation grommets 220 is also slightly greater than the inside diameters 174, 176 of the collars 170, 172. Thus, the body portions 226 are pre-stressed upon insertion into the collars 170, 172. Also, when a reaction load is exerted on the isolation mounts 210 (from the collars 170, 172) the body portions 226 of the isolation grommets 220 will compress. If compression continues, the collar will contact the sleeve 230, which adds further resilience to the movement of the front drive 6. The sleeve 230 may have a higher durometer reading than that of the isolation grommets 220, such that the sleeve 230 is stiffer than the isolation grommets 220. This provides a dual rate spring effect to the collars 170, 172.

(30) For example, the sleeve 230 may have a hardness (durometer reading) in the medium soft to medium hard range, whereas the isolation grommets 220 may be in the range of soft to medium soft. Also, the material composition may be consistent throughout the isolation mounts or it may be different. Moreover, the isolation mounts may be an integrated component or be in plural components. It is anticipated that the isolation mounts are comprised of a rubber-like substance.

(31) Because the front drive 6 is suspended by the top of the front drive 6, the front drive 6 can be suspended over the lower frame tubes 26, with a portion of the front drive 6 being positioned between and lower than the lower frame tubes 26. By minimizing the spread distance between the front frame tubes 26, a length of the lower A-arms can be maximized while keeping the same track width. Furthermore, by providing the isolation mounts 220 as disclosed, forged gear sets may be used and have the NVH levels (noise/vibration/harshness) of much more expensive gear sets.

(32) As an alternative to the one-piece mount 8 shown in FIG. 4, mount 308 as shown in FIG. 11 has a two-piece construction including mount portions 308a and 308b. Each of the mount portions 308a, 308b has a top wall at 370, side walls at 372 and rear bracket walls at 374. Side walls 372 include mounting apertures 376 and 380 therethrough. The mount 308 has front flanges 378 with apertures 380 for fastening the mount 308 to the front frame portion 4. Mount 308 would otherwise operate in the same manner with fasteners 82 being receivable through apertures 376 and 380 to receive washers 84 and fasteners 86 as described herein. Rear bracket wall 374 would couple to the posts 100, 102 as previously described herein.

(33) While this invention has been described as having an exemplary design, the present invention may be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains.