Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02287615 1999-10-28
1 FIELD OF THE INVENTION
2 The present invention relates to an adapter for use in applying a
3 standard brake lathe to machine the rotor surfaces of a rotorlhub/bearing
4 assembly from a four wheel drive vehicle.
6 BACKGROUND OF THE INVENTION
7 In certain four wheel drive vehicles, the wheel hub and brake pad rotor
8 are formed separately and bolted together. The hub supports a bearing
9 assembly. The bearing assembly bolts to the stationary vehicle axle and the
hub and rotor rotate with the vehicle drive shaft.
11 It is occasionally necessary to grind or machine the front and rear
12 surfaces of the rotor. This is done to remove warpage arising from wear and
13 heat, to produce a re-conditioned rotor having true surfaces.
14 In most smaller brake shops, a small lathe, known as a standard or
bench brake lathe, is used to grind the rotor surfaces. In this connection,
the
16 rotor/hub/bearing assembly is first disassembled. The rotor is then mounted
17 on the lathe arbor or shaft using cones to center the rotor, so that its
surfaces
18 are oriented perpendicular to the axis of the arbor. The arbor is then
rotated
19 to turn the rotor relative to the cutting elements of the lathe.
There are two problems inherent in this system, namely:
21 ~ there is significant time and cost involved in disassembling the
22 rotor/hub/bearing assembly. Typically this might involve about 1-
23 1 /2 hours to do; and
2
CA 02287615 1999-10-28
1 ~ the rotor, when mounted on the cones, does not turn precisely as it
2 would if it were mounted on the vehicle drive shaft because the hub
3 and bearing assembly has been removed and replaced with the
4 cones. As a result, when the parts are reassembled and mounted
on the vehicle, there is a good possibility that the rotor surfaces will
6 not be "true" or precisely perpendicular relative to the axle. This
7 leads to a vibration of the vehicle in use, referred to as brake pedal
8 pulsation.
9 There are commercially available on-vehicle brake lathes designed to
grind the rotor surfaces while the rotor, hub and bearings remain assembled
11 in place on the vehicle. While, these lathes produce a true ground rotor
12 surface, they are however relatively expensive to purchase and few small
13 brake shops are equipped with them.
14 It would therefore be desirable to modify the standard brake lathe and
enable it to turn the entire rotor/hublbearing assembly in the course of
16 machining, to achieve "on-vehicle" quality re-surfacing.
17
18 SUMMARY OF THE: INVENTION
19 In accordance with the invention, an adapter is provided which is
operative to fit on the arbor of a standard brake lathe and to further conform
21 with and support the flange surface and l:he internal surface of the hub
and
22 bearing assembly of the rotorlhub/bearinc,~ assembly. The adapter enables
23 the rotor/hub/bearing assembly to be turned and machined as a unit, without
24 disassembly. As a result, the ground ro~ror surfaces will turn as true when
mounted on the vehicle axle as they are when turned on the lathe arbor.
3
CA 02287615 1999-10-28
1 Broadly stated, the invention is an adapter for use on the arbor of a
2 standard brake lathe to support a four wheel drive vehicle rotorlhublbearing
3 assembly so that the assembly may be turned to enable grinding of the rotor,
4 the assembly comprising a hub and bearing assembly having an inner end
surface and a stepped axial bore surface, said adapter comprising: a flange
6 and a tubular shaft extending perpendicularly and centrally from the flange;
7 the adapter flange being configured to conform with the inner end surface of
8 the hub and bearing assembly; the adapter shaft having an internal
cylindrical
9 axial bore sized to fit the lathe arbor and a~n outer stepped surface
configured
to conform with the axial surface of the hub and bearing assembly, the outer
11 stepped surface having a central axis coincident with the bore axis.
12
13 DESCRIPTION OF Tf~E DRAWINGS
14 Figure 1 is a front perspective view of the adapter;
Figure 2 is a rear perspective view of the adapter;
16 Figure 3 is a perspective, partly exploded view showing the brake
17 arbor, adapter, rotor/hublbearing assembly and lock nut, prior to assembly;
18 and
19 Figure 4 is a sectional side view of the rotorlhublbearing assembly
mounted on the adapter on the brake lathe arbor.
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CA 02287615 1999-10-28
1 DESCRIPTION OF THE PREFIERRED EMBODIMENT
2 Having reference to Figures 3 and 4, the rotor/hublbearing assembly 1
3 comprises a rotor 2 bolted to the hub 3 of a hub and bearing assembly 4. The
4 hub 3 supports a bearing assembly 5 and together they combine to form the
hub and bearing assembly 4.
6 The hub 3 has an axial bore 6 formed by an inner, partly splined,
7 stepped surface 7. The hub and bearing assembly 4 has an inner end
8 surface 8.
9 The adapter 10 is a body 11, preferably formed of steel, comprising a
flange 12 and an outwardly protruding, cylindrical shaft 13 extending
centrally
11 from the flange. The body 11 forms an axial bore 14, sized to conform with
12 and closely fit the arbor 15 of the rake lathe 16. The adapter shaft 13 has
an
13 outer surface 17 configured to conform vvith and closely fit the hub's
inner
14 stepped surface 7.
When assembled as shown in Figure 4, the adapter 10 supports and
16 centralizes the entire rotor/hublbearing assembly 1 on the lathe arbor 15.
The
17 adapter shaft surface 17 conforms with and fits hub stepped surface 7. The
18 surface 18 of the adapter flange bears against the end surface 8 of the hub
19 and bearing assembly 4, the lock nut 20 and spacers 21 are tightened to
lock
the assembly 1 to the arbor 15.
21 The lathe 16 may then be actuatedl to rotate the entire assembly 1 so
22 that the lathe cutting elements (not shown) may be used to machine the
rotor
23 surfaces 22 to achieve "on-vehicle" quality re-surfacing.
5
CA 02287615 1999-10-28
1 Although a specific best mode embodiment of the invention has been
2 described, it is contemplated that modifications may be made without
3 departing from the spirit and scope of they invention which is defined by
the
4 claim now following.
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