Axle differential with stamped carrier cover pan
In combination, a cover and a seal, the combination includes a cover including a mounting face having a plurality of raised connection points. The cover is adapted to enclose an opening in a housing. A seal includes a plurality of section encircling a plurality of raised connection points. The plurality of encircling sections has a thickness greater than a distance the connection points are raised above the mounting face. The seal sections are adapted to compress to a thickness equal to the distance when the cover is mounted to the housing.
This application is a continuation of U.S. patent application Ser. No. 10/755,962 filed on Jan. 12, 2004. The disclosure of the above application is incorporated herein by reference.
FIELDThe present invention relates to a differential cover for a vehicle drivetrain assembly and further relates to a double seal ring that is pre-attached to the differential cover that also includes integral compression limiters.
BACKGROUND A differential assembly houses a gear assembly that is traditionally configured to change a direction of a power input from a drive shaft to two half shafts. The drive shaft receives power from an engine and through a transmission, while the half shafts deliver power to the wheels from the differential assembly. With reference to
Based on their construction, solid beam axle housings can be divided into two groups, an integral carrier, or a removable carrier. The integral carrier housing attaches directly to the rear suspension. A service cover, in the center of the housing, fits over the rear of the differential and axle assembly. When service is required, the cover must be removed and the components of the differential unit are then removed. Integral carriers are also commonly referred to as unitized or salisbury-type differentials, named after C. W. Salisbury one of the founders of Salisbury Axle Company.
A removable carrier assembly is configured so that the gearing assembly can be removed from the front of the differential housing as a unit, when the front portion of the differential housing unit is removed. With reference to rear live axles, a rear axle refers an axle mounted in the rear of a vehicle and to the rear tires. The front of the rear axle refers to the area which the driveshaft connects thereto and live denotes that the axle carries power, such as in a rear wheel drive vehicle. The typical housing of a removable carrier assembly has a cast-iron center section with axle shaft tubes pressed and welded into either side. The removable carrier assembly is sometimes called a “banjo” because of the bulge in the center of the housing. The bulge contains the final drive gears and differential gears. In appearance, the two designs of axle housing look similar except that the opening for the differential unit on a banjo axle is at the front and the rear of the housing is solid, while access to the salisbury axle is through a rear service cover.
It will be appreciated that variations of the salisbury and the banjo axles exist, such as independent front and rear axles. With an independent front or rear axle, the differential housing is mounted to the vehicle's chassis. As such, the differential housing does not move with the suspension. The half axles, however are connected to the wheels of vehicle which are suspended. To that end, constant velocity joints are used to connect the half axles to the differential assembly and the wheel hubs so that the half axles are able to move with the suspended wheels. The differential housing remains unsuspended and secured to the applicable subassemblies of the vehicle.
With reference to
It will be appreciated that the gasket 28 must be placed over the housing 14 in a proper orientation to ensure proper installation when the cover 22 is secured to the housing 14. It will be further appreciated that misalignment of the gasket 28 may lead to improper sealing of the gasket 28, which may manifest itself in leaks from the housing 14. Misalignment may also cause the gasket 28 to be pinched or crimped by the fasteners 26 when the cover 22 is secured to the housing 14. The pinched or crimped gasket 28 may also improperly seal when the cover 22 is secured to the housing 14.
When the cover 22 is secured to the housing 14, the fasteners 26 must be secured so as to apply a clamping force about the perimeter of the cover 22. The clamping force causes the gasket 28 to compress and thus form a seal between the cover 22 and the housing 14. The gasket 28 not only serves to retain the internal lubrication of the differential assembly 10, but also protects the differential assembly from the regimes of driving environment, such as water, salt, and dirt. It will be appreciated that the axle of a vehicle is located along the underbelly of the vehicle and by the very nature of its location is exposed to not just water, salt, and dirt as mentioned above but may also be exposed to high-pressure water from conventional car washes. It will be appreciated that the gasket 28 must not only seal the lubrication in the differential assembly, it must also keep many things out of differential assembly, so water, dirt, salt and the like does not pollute the lubrication.
To that end, an incorrect amount of clamping force applied to the cover 22 may lead to improper sealing of the gasket 28. Over-tightening the fasteners 26, for example, may generate too much clamping force and over compress the gasket 28, such that the gasket 28 may bulge or kink, which is sometimes referred to as coining. Coining and over-compression in general may lead to leaks especially when the gasket expands and contracts due to heating and cooling the assembly 10.
It is desirable, therefore, to secure the differential assembly cover to the housing without a separate compression limiting device. It is further desirable to have the compression limiting device pre-configured into the differential assembly cover. It is also desirable to have a seal pre-attached to the differential assembly cover that is cost-effective and robust. It is additionally desirable to avoid the steps of aligning the gasket while securing the differential assembly cover to the housing.
SUMMARYAn axle assembly that includes a differential gearset in a carrier housing. A housing cover is coupled to the carrier housing and is operable for sealingly closing a window on the carrier housing through which there is access to the differential gearset. The housing cover includes a cover member and a seal ring. The cover member includes a mating face and a plurality of raised connection points that are disposed between the carrier housing and the mating face. The seal ring is coupled to the mating face and encircles each of the raised connection points. The seal ring further includes at least first and second ring members that are disposed between each of the raised connection points. The seal ring sealingly engages the carrier housing and the mating face.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGSThe present invention will become more fully understood from the detailed description, the appended claims, and the accompanying drawings, wherein:
The following description of the various embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
With reference to
A seal ring 106 encircles a perimeter 108 of the cover 100. The perimeter 108 of the cover 100 includes a cover mating face 110. The seal ring 106 is connected to the cover mating face 110, which encircles the bowl portion 102, such that when the cover 100 is attached to the housing 14 (
The seal ring 106 may include at least a first sealing member 112 and a second sealing member 114 that may be approximately concentric with the first sealing member 112. The seal ring 106 can also include a web member (not shown) that connects the first sealing member 112 to the second member 114. It will be appreciated that either the first sealing member 112 and/or the second sealing member 114 may be individually applied or connected to the cover mating face 110 directly or as an assembly incorporating the web member (not shown) therebetween.
In the various embodiments of the present invention, the seal ring 106 is attached to the cover mating face 110 with a suitable adhesive. It will be appreciated that when the cover 100 is secured to the housing 14 (
The cover 100 also includes a plurality of raised connection points 116. The plurality of raised connection points 116 are integral to the cover mating face 110 and define a plurality of apertures 118 within the connection points 116 spaced along the perimeter 108 of the cover 100. In the various embodiments, there are ten (10) connection points 116 that are approximately equally spaced apart from one another. It will be appreciated, that while ten (10) connection points 116 are depicted in
The seal ring 106 encircles each connection point 116 so that a continuous seal is formed around the bowl portion 102 of the cover 100. It will be appreciated that the raised connection point 116 is at a different elevation than a portion of the cover mating face 110 adjacent to the raised connection point 116, as shown in
In the various embodiments, the cover 100 can be stamped as one piece. The stamping process creates, among other things, the bowl portion 102, the raised connection points 116, and the cover mating face 110 along with the general geometry of the bowl. Moreover, the seal ring 106 can be affixed to the cover 100 during the stamping process, so that the cover 100 and the seal ring 106 can be produced as a single unit. This can not only eliminate the need to match the cover 100 to the gasket 28 (
With reference to
With reference to
In the various embodiments, the housing 132 can be a salisbury differential housing, wherein the cover 100 is a modified housing cover configured to secure to a salisbury differential housing. The cover 100 may also be modified to seal to an axle assembly configured with independent suspension or to various transaxles. Moreover, the cover 100 can also be used in other areas of the vehicle beyond its use on front or rear axles.
The cover 100 is placed over the housing 132 and secured to the housing with the plurality of fasteners 122. It will be appreciated that when the apertures 118 of the connection points 116 are aligned with the housing mounting face 130, the seal ring 106 is necessarily aligned properly to the housing 132. The plurality of fasteners 122 are then used to secure the cover 100 to the housing 132. When the fasteners 122 are secured, the configuration of the cover 100 is such that the seal ring 106 is properly compressed between the cover mating face 110 and the housing mounting face 130. As such, the seal ring 106 can be compressed by an amount equal to the compression distance between the cover mating face 110 and the housing mounting face 130, while the connection points 116 make direct contact with the housing mounting face 130.
It will be appreciated that a proper seal between the housing cover 100 and the differential housing 132 is required to not only contain lubrication within the differential housing 132 but also keep out the many pollutants to which the exterior of the differential housing is exposed. Some of the pollutants, for example, include water, salt spray, dirt, oil, and the like. Moreover, axle assemblies are commonly exposed to high-pressure wash systems or driven through water both of which can add to the need to have a robust seal between the housing cover 100 and differential housing 132.
Other devices can be employed to address compression of the seal ring 106 a proper distance or put another way to limit compression. Any such device must not only be robust, easy to use, and compliant with other materials, it must also be cost effective in a mass production scale.
The shoulder bolt 134 can be inserted into a threaded aperture 148 or a conventional nut. It will be appreciated that the shoulder bolt 134 can only be inserted a distance 144 into the threaded aperture 148. As shown in
In lieu of the shoulder bolt 134, a compression limiter (not shown) may be introduced between the cover 100 and the housing 132 to establish a proper compression distance for the seal ring 106. In various embodiments, a compression limiter may take the form of a sleeve (not shown) over a conventional fastener, which may be used to limit the insertion of the fastener. While introducing compression limiters may be a less expensive option than using shoulder bolts, compression limiters add to the overall parts count of the assembly and can increase the overall cost of the process.
The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.
Claims
1. In combination, a cover and a seal, the combination comprising:
- a cover including a mounting face having a plurality of raised connection points, the cover being adapted to enclose an opening in a housing; and
- a seal having a plurality of sections encircling the plurality of raised connection points, the plurality of encircling sections having a thickness greater than a distance the connection points are raised above the mounting face, the seal sections being adapted to compress to a thickness equal to the distance when the cover is mounted to the housing.
2. The combination of claim 1, wherein the raised connection points are adapted to make direct contact with the housing and limit an amount by which the seal may be compressed between the mounting face and the housing.
3. The combination of claim 2, wherein the seal ring includes first and second concentric ring members that are positioned between each of the raised connection points, wherein the ring members are adapted to sealingly engage the mounting face.
4. The combination of claim 3, further comprising a web member connected to the first ring member and the second ring member.
5. The combination of claim 4, wherein the cover includes a plurality of fastener apertures extending through the plurality of connection points.
6. The combination of claim 5, wherein each of the first and second ring members is coupled at opposite ends to a pair of the encircling portions.
7. The combination of claim 6, wherein the seal is formed from an elastomeric material.
8. The combination of claim 1, wherein the seal is configured to remain clear of the connection points to allow the connection points to directly engage the housing.
9. In combination, a cover and a seal, the combination comprising:
- a cover including a flange having a mounting face and a plurality of pads circumferentially spaced apart from one another, each pad having a substantially planar contact surface adapted to engage a housing, each contact surface being offset from and substantially parallel to the mounting face; and
- a seal having a plurality of sections encircling the pads, the plurality of encircling sections having a thickness greater than a distance the contact surfaces are offset from the mounting face.
10. The combination of claim 9, wherein a fastener aperture extends through one of the pads.
11. The combination of claim 10, wherein the encircling sections are adapted to compress to a thickness equal to the distance when the cover is mounted to the housing.
12. The combination of claim 9, wherein each of the contact surfaces are aligned in a single plane.
13. The combination of claim 9, wherein the encircling portions are interconnected to one another by a first set of ring portions.
14. The combination of claim 13, further including a second set of ring portions interconnecting the encircling portions, the second set of ring portions being arranged concentrically with the first set of ring portions.
15. A method of assembling a cover and a seal to a housing, the housing having a cavity with a window providing access to the cavity and a housing face surrounding the window, the cover being adapted to enclose the window and including a mounting face having a plurality of connection points protruding from the mounting face, the connection points being adapted to engage the housing face, the seal having a plurality of sections sized to encircle the plurality of connection points, the method comprising:
- positioning the seal between the housing face of the housing and the mounting face of the cover;
- aligning the encircling portions of the seal with the connection points;
- inserting a plurality of fasteners through apertures extending through the connection points;
- placing the connection points in direct contact with the mounting face of the housing; and
- engaging the fasteners with the housing to secure the cover to the housing and compress the seal a predetermined amount equal to a distance the seal protruded beyond the connection points prior to securing the cover to the housing.
16. The method of claim 15, further including threadingly engaging the fasteners with the housing.
17. The method of claim 16, further including aligning each of the connecting points along a single plane.
18. The method of claim 17, further including rotatably supporting a differential assembly within the cavity.
19. The method of claim 18, further including attaching the seal to the to placing the connection points in direct contact with the mounting face.
20. The method of claim 15, further including positioning the seal clear of the connection points.
Type: Application
Filed: Feb 27, 2006
Publication Date: Jul 20, 2006
Inventor: Kevin Beutler (Columbiaville, MI)
Application Number: 11/363,102
International Classification: F02F 11/00 (20060101); B21D 53/84 (20060101);