Abstract:
A rolling bearing unit with a pair of axially spaced grooves in the shaft, rolling bearing elements in the grooves, sheet metal outer race elements secured in a housing, and an adjusting ring for driving one of the outer race elements axially relative to the housing and to the other race element.

Description:
BACKGROUND OF THE INVENTION 
     This invention is in the field of rolling bearings, in particular a bearing with adjustment for the seating and play of the bearing on a pedal bearing shaft which includes two outer rings fixed in a housing bore and two rows of balls arranged in grooves on the shaft. 
     Such a bearing for pedal bearing shafts is disclosed in, for example, the prior art West German Pat. No. OS 21 42 954. This bearing consists of a series of complicated individual parts, the manufacture of which is relatively expensive. In addition, assembly of this bearing is cumbersome and time-consuming and may be done by automatic equipment only with difficulty. 
     It is therefore an objective of the present invention to provide a roller bearing unit of the type mentioned above which consists of parts inexpensive to manufacture, is supplied as a unit by the manufacturer, and may be assembled using automatic equipment. 
     SUMMARY OF THE INVENTION 
     The objective noted above is accomplished in a rolling bearing unit of the aforementioned type in that the two outer rings consist of two cup or pot-shaped parts of sheet metal with flanges directed radially inward, one of the outer rings being fixed in the housing bore by a split retaining ring, and the other outer ring being axially adjustable by means for adjusting the bearing play, which means have tapered surfaces on the sides turned toward the parts to be attached. 
     According to one preferred embodiment of the invention, the split retaining ring is inserted in an annular groove on the surface of one of the outer rings and rests on a tapered bore surface of the housing. The other outer ring in this embodiment is provided on the surface with a threaded section on which is arranged an adjusting ring, a tapered surface of which engages a tapered bore surface of the housing. It is easy to see that this design of the bearing parts permits inexpensive manufacture and easier assembly of the bearing by efficient automatic equipment. 
     According to another preferred embodiment, the split retaining ring is arranged in an annular groove of the housing and rests on the rounded-off surface of one of the outer rings. Inserted in the threaded bore of the housing is an adjusting ring, a tapered bore surface of which engages the rounded-off surface of the other outer ring. This results in a design requiring still less accurately worked surfaces and hence is still less expensive to manufacture. 
     The invention is described in greater detail below by reference to two embodiments represented schematically in the drawings attached hereto. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an axial section view showing a first embodiment of a pedal bearing unit with adjustable play; and 
     FIG. 2 is a similar view showing a second embodiment of a pedal bearing unit with adjustable play. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the bore 1 of a housing 2, represented schematically in FIG. 1, are inserted, in an O arrangement, two inclined ball bearings 3 and 4, which serve for seating a pedal bearing shaft 5. The pedal bearing shaft 5 has an essentially constant diameter and two grooved races 6 for the rolling elements 7. The outer rings 8 and 9 made of thin-walled sheet metal, are cup or pot-shaped, while the flanges 10, directed radially inward, confront one another and extend to near the pedal bearing shaft 5. In the shoulders 11 of the outer rings 8 and 9, sealing disks 12, having an L-shaped cross section, are provided the radially extended arm of each of which reaches, except for a clearance, to the surface 13 of the pedal bearing shaft 5. A split ring 14, with O-shaped cross section, which is inserted in an annular groove 15 on the surface of the outer ring 9 and rests on a tapered bore surface 16 of the housing 2, serves for axial fixation of the inclined ball bearing 4 (on the right-hand side of the drawing). On the surface of the outer ring 8 (on the left-hand side of the drawing), a threaded section 17 is provided, on which is screwed an adusting ring 18, a tapered surface 19 of which engages in a corresponding bore surface 20 of the housing 2. The adjustment of bearing play is made by the adjusting ring 18, which when screwed on the outer ring 8 is supported against the tapered bore surface 20 of the housing 2 and draws the outer ring 8 outward. At the same time the flange 10, directed radially inward, of the outer ring 8 extends behind the rolling elements 7 and shifts the latter with the shaft 5 to the left until the desired bearing play is obtained. 
     The pedal bearing unit shown in FIG. 2 consists of two similarly designed inclined ball bearings 21 and 22, which are inserted in the housing bore 1 in an X arrangement, so that the flanges 23 and 24 which extend drawn radially inward of the outer rings 25 and 26, are turned away from each other. Axial fixation of the right-hand outer ring 26 is likewise obtained by a split O-shaped ring 27 which engages an annular groove 28 in the bore 1 of the housing 2 and inwardly abruts the rounded-off section 29 of the outer ring 26. The adjustment of the bearing play is effected by an adjusting ring 31, which is provided with a tapered bore surface 30 and abuts the rounded-off surface 32 of the outer ring 25. When the adjusting ring 31 is screwed in, the left-hand bearing 21 and the pedal bearing shaft 5 are shifted to the right and the bearing play is thereby adjusted. The adjusting ring 31 is secured against turning by a plate spring 33, which is supported against the face 34 of the housing 2 and against the lateral surface 35 of the adjusting ring 31. The rolling bearing unit is sealed off on one side by a disk 36 arranged on the pedal bearing shaft 5, which disk encloses the outer housing section 37 with clearance. On the other side, a sealing ring 38 is arranged in a recess 39 formed in the adjusting ring 31 and rests on the pedal bearing shaft 5. 
     In the embodiments described, good centering of the bearing parts and bracing of the outer rings 8, 9 and 25, 26 by the housing 2 are obtained by, for example, cooperation of the tapered surfaces 19 and 20 and cooperation of the tapered surface 30 and rounded surface 32, respectively. 
     The embodiments described represent merely examples of a rolling bearing unit pursuant to the invention. Variations in the design of the individual components are of course possible within the scope of the invention.