Bearing retainer for U-joint shaft end

Abstract: A bearing assembly (20) that is preferably used on carden universal joint shafts. A bearing retainer (32) maintains a plurality of needle bearings (28) at a desired location during shipment, and maintains the bearing assembly (20) on the shaft (22) prior to assembly. The bearing retainer (32) preferably has an inner periphery diameter that is less than the outer diameter of the shaft (22), and an outer diameter that is less than the inner diameter of the bearing housing (26). In this way the bearing retainer (32) locks on the outer periphery of the shaft (22) at its inner periphery and clearance (36) is provided at the outer periphery of the retainer (32) such that it rotates with the shaft (22) within the housing (26).

Description: This application relates to a bearing retainer that has particular utility in supporting a universal joint shaft. Prior art universal joints have shaft ends which may each be mounted in a bearing cup that receives a plurality of needle bearings. The shafts rotate through limited angular extents relative to the bearing cup as the universal joint operates. Bearing retainers may be used with these bearings to retain the needle bearings in a proper position during shipment. Prior art bearings utilize a plurality of different types of bearing retainers that may not lock the shaft within the bearing cup during shipment. US-A-2976091 discloses a universal joint comprising: at least one shaft having an outer diameter, said shaft being rotatably received in a bearing assembly, said bearing assembly including a housing having first and second ends and an inner peripheral surface defining a housing bore of a first bore diameter, the shaft having a cylindrical shaft end extending into said housing bore from said second end and not extending beyond said first end; bearing members received within said housing bore, and means at said first end of said housing to prevent movement of said bearing members beyond said first end; and a ring-shaped bearing retainer mounted adjacent said bearing members and on a side of said bearing members spaced axially towards said second end to axially retain said bearing members within said housing bore, said bearing retainer having an inner peripheral surface defining a bearing retainer bore of a second bore diameter, which is less than the shaft outer diameter, the cylindrical shaft end being an interference fit in said bearing retainer bore. According to the present invention the bearing retainer is deflectable such that the interference fit deforms said inner peripheral surface of said bearing retainer bore towards said first end, locking said bearing retainer on said shaft, and the universal joint further comprises a seal which is forced into said housing from said second end, on a side of said bearing retainer spaced axially toward said second end, to secure said bearing retainer within said housing and to maintain said housing on said shaft. The inner periphery of the bearing retainer thus extends radially inwardly beyond the inner periphery of the bearing members. In the universal joint according to the invention, the bearings may be retained on the shaft, using the bearing retainer, during shipment. Furthermore, the bearing retainer remains within the housing during operation of the universal shaft and does not need to be removed prior to use. The bearing retainer used in the universal joint according to the invention maintains the bearing members in a desired position during use, and prevents the bearing members from contacting and damaging the seal during use. In a preferred embodiment the bearing retainer has an outer diameter less than the inner diameter of the housing such that there is a clearance between the two. The bearing retainer can thus rotate with the shaft within the bearing housing, and will not interfere with the other members of the bearing assembly. The shaft is preferably a carden universal joint cross shaft. The shaft does not actually rotate through 360° within the bearing, and hence the term rotation as used throughout this application may refer to movement of the shaft through a limited angular extent relative to the bearing housing. It should be understood, however, that the universal joint according to the invention has benefits which extend to other types of shafts, including fully rotating shafts. In a method of assembling a bearing assembly of the present invention, a bearing cup receives a plurality of the bearing members. An optional spacer may be inserted into the bearing cup prior to the bearing members. The bearing retainer is then placed within the cup and a seal is inserted to secure the bearing retainer. A shaft is then inserted into the cup and deflects the inner periphery of the bearing retainer axially further into the cup. The retainer locks on the shaft end, securing the bearing assembly to the shaft. These and other objects and features of the present invention can be best understood from the following specification and drawings. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a largely schematic view of a universal joint embodying the inventive bearing of the present invention. Figure 2 is an assembly view of an inventive bearing. Figure 3 is a view of detail 3 as shown in Figure 1. Figure 4 is a front view of a bearing retainer according to the present invention. Figure 5 is a view similar to Figure 4, but showing a second embodiment of the bearing retainer. DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT Shaft bearing assembly 20 for mounting carden universal joint shaft 22 is illustrated in Figure 1. Shaft 22 has shaft end 24 received in bearing cup 26, with a plurality of needle bearings 28 rotatably guiding shaft end 24. Spacer 30 is received between cup end 31 and needle bearings 28. Retainer 32 is received in the open end of bearing cup 26 and maintains bearings 28 in a desired position. Retainer 32 has an inner periphery diameter that is less than the outer diameter of shaft end 24, and thus locks in an interference fit onto shaft end 24. The outer diameter of retainer 32 is less than the inner periphery diameter of bearing cup 26, providing clearance 36 such that retainer 32 moves freely within bearing cup 26 as shaft end 24 rotates. The term rotation as used within this application may refer to the normal movement through a limited angular extent that shaft 22 may perform relative to bearing cup 26 during operation of a universal joint. It should be understood, however, that the inventive bearing has benefits which extend to other types of shafts, including fully rotating shafts. Seal 34 is forced into the open end of bearing cup 26 and maintains bearing retainer 32 in a desired position. Retainer 32 ensures that bearing cup 26 remains on shaft end 24, particularly during shipment. Retainer 32 also ensures that needle bearings 28 do not contact seal 34 during shipment or use. Figure 2 is an exploded view of bearing assembly 20. Cup 26 initially receives spacer 30, then a plurality of needle bearings 28, and then bearing retainer 32. Retainer 32 has a plurality of scalloped openings 38 at an outer periphery which allow air or lubricating fluid to move between the axial sides of retainer 32. Seal 34 is inserted and secures bearing retainer 32 within cup 26. Shaft end 24 is then forced into bearing cap 26, and its outer periphery is forced into an interference fit in the inner periphery 40 of retainer 32. The assembly is relatively simple and may be performed mechanically. As shown in Figure 3, when shaft end 24 is forced into inner periphery 40, bearing retainer 32 deflects or bends to position 42, locking on shaft end 24. The deflected retainer 32 could be described as having a circular concave deflection at inner periphery 40. When shaft end 24 rotates relative to bearing cup 26, retainer 32 rotates with the shaft. Since there is clearance 36 at the outer periphery of bearing retainer 32, this rotation does not affect the other portions of bearing assembly 20. Figure 4 is a front view of bearing retainer 32 including scalloped openings 38. Inner periphery 40 is smaller than the outer diameter of a shaft with which the retainer is to be used. Figure 5 shows an alternative embodiment retainer 44. Bearing retainer 44 has a number of small openings 46 at its outer periphery which allow fluid to flow between its axial faces. A bearing retainer for use on a shaft having an outer diameter of 16.74 - 17.0 mm (.659-.670 inches) may have an inner diameter between 16.43 - 16.51 mm (.647 and .650 inches). Such a sized bearing retainer would preferably be 0.51 - 0.64 mm (.020-.025) inches in width. The bearing retainer is formed from a plastic or elastomeric material. Preferably, nylon is used. Most preferably, Nylatron™ is used. The seal is preferably metal-backed. The other portions of bearing assembly 20 are formed of known materials. A preferred embodiment of the present invention has been disclosed, however, a worker of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. For that reason the following claims should be studied in order to determine the true scope and content of this invention.

Claims: A universal joint comprising: at least one shaft (22) having an outer diameter, said shaft being rotatably received in a bearing assembly (20), said bearing assembly (20) including a housing (26) having first and second ends and an inner peripheral surface defining a housing bore of a first bore diameter, the shaft (22) having a cylindrical shaft end (24) extending into said housing bore from said second end and not extending beyond said first end; bearing members (28) received within said housing bore, and means (30,31) at said first end of said housing to prevent movement of said bearing members (28) beyond said first end; and a ring-shaped bearing retainer (32) mounted adjacent said bearing members (28) and on a side of said bearing members (28) spaced axially towards said second end to axially retain said bearing members (28) within said housing bore, said bearing retainer (32) having an inner peripheral surface (40) defining a bearing retainer bore of a second bore diameter which is less than the shaft outer diameter, said cylindrical shaft end (24) being an interference fit in said bearing retainer bore, characterised in that the bearing retainer is deflectable such that the interference fit deforms said inner peripheral surface (40) of said bearing retainer bore towards said first end, locking said bearing retainer on said shaft, and in that the joint further comprises a seal (34) which is forced into said housing (26) from said second end, on a side of said bearing retainer (32) spaced axially toward said second end, to secure said bearing retainer (32) within said housing (26) and to maintain said housing (26) on said shaft (24). A universal joint as claimed in claim 1, wherein said bearing retainer (32) has an outer diameter which is less than said first bore diameter such that there is a clearance between said bearing retainer (32) and said housing inner peripheral surface. A universal joint as claimed in claim 2, wherein an outer peripheral surface of said bearing retainer (32) in non-circular and said inner peripheral surface of said housing (26) is circular such that clearances exist between said bearing retainer outer peripheral surface and said housing inner peripheral surface. A universal joint as claimed in any preceding claim, wherein said bearing members (28) are elongate needle bearings. A universal joint as claimed in any preceding claim, wherein said housing (26) is cup-shaped with an open second end and said means to prevent movement is a closed face (31) on said housing (26) at said first end. A universal joint as claimed in any preceding claim, wherein said bearing retainer (32) is formed from an elastomeric material.

Inventors: MARRIOTT THOMAS J, PEARSON MARTIN J, MARRIOTT, THOMAS J., PEARSON, MARTIN J.
Applicants: DANA CORP, DANA CORPORATION
Application year: 1992
Main classification: F16C19
IPC codes: F16C43, F16D3, F16C19, F16C41, F16C33, F16C21, F16C35