Brakes – Elements – Brake wheels
Reexamination Certificate
1999-06-11
2001-10-23
Oberleitner, Robert J. (Department: 3613)
Brakes
Elements
Brake wheels
C188S073200, C188S073380
Reexamination Certificate
active
06305510
ABSTRACT:
This invention is concerned with a disc brake system, for example for a wheel of a vehicle.
A conventional disc brake system of a vehicle comprises a hub mounted on a suspension link for rotation relative thereto about a central rotational axis. The hub provides a mounting for the wheel. The system also comprises a brake disc mounted on the hub to rotate therewith, friction material pads arranged on opposite sides of the disc, and at least one piston and cylinder assembly operable to urge the pads into engagement with the disc, to brake the hub and hence the wheel. Conventionally, the piston and cylinder assembly is slidably mounted on a slide bolted to the suspension link of the vehicle. The disc is conventionally rigidly fixed to the hub, and wear of the pads and/or the disc is accommodated by the sliding movement of the cylinder.
Disc brake systems which have discs which are non-rotational relative to the hub but slidable on the hub by means of splines or other non-circularity of the hub and the disc are also known, see, for example, GB 1 396 503. However, such systems are associated with technical problems. For example, since the discs are relatively thin, they tend to tilt on the hub and affect the braking ability. Also, there is a tendency for noise to be produced by rattle of the disc against the hub. At higher disc temperatures, these problems can be particularly severe since, when there is a large temperature differential, such as 600° C., between the braking surface of the disc and the hub, the disc expands considerably, away from the hub, exacerbating the problems of tilting and rattle.
The present invention addresses these technical problems.
According to the present invention, there is provided a disc brake system comprising a hub, and a disc, the hub being mounted for rotation about a central rotational axis and the disc being mounted on the hub to rotate therewith, wherein the disc is slidable on the hub in a direction which is parallel to said central rotational axis, characterised in that the system also comprises a plurality of resilient force applicators which are mounted between the hub and the disc, the force applicators acting to apply radially-directed forces to the disc, the force applicators being distributed circumferentially around the hub.
In a disc brake system according to the invention, the forces applied by the resilient force applicators serve to reduce noise from rattle of the disc against the hub, to control the sliding movement of the disc on the hub, to control the concentricity of the disc with the hub, and to provide stability of the disc to avoid tipping. In order to reduce disc wear, a disc brake system according to the invention may have two or more discs mounted side-by-side on the same hub, the resilient force applicators acting on all the discs.
Preferably, in order to achieve improved concentricity of the disc on the hub, the resilient force applicators are substantially equispaced about the central rotational axis. There may be at least three equally-spaced resilient force applicators.
Preferably, the force applicators are leaf springs. Each leaf spring may be secured to the outer surface of the hub in a manner such that the spring extends tangentially of the hub when the disc is not mounted on the hub.
In one possibility, the hub and the disc have intermeshing surface features which prevent relative rotational movement between the hub and the disc but allow relative movement parallel to the central rotational axis, there being spaces between said intermeshing surface features in which said force applicators are mounted. Said intermeshing surface features may comprise axially-extending splines on the external surface of the hub and teeth projecting from the internal surface of the disc.
In another possibility which reduces wear problems where the hub and the disc engage one another and difficulties in manufacturing intermeshing surface features, the internal surface of the disc and the external surface of the hub are formed with recesses in which a plurality of axially-extending rollers are captive, the rollers serving to transmit rotational drive between the hub and the disc, the disc being slidable axially on the rollers and hence relative to the hub. It is known from GB 983 548 to transmit driving force between the hub and the disc by means of axially-extending rollers which are captive between the hub and the disc. In this case, the leaf springs may be positioned between the rollers around the hub. Alternatively, at least some of the leaf springs may have an opening therein in which one of the rollers is received. Preferably, in order to reduce corrosion problems, the rollers have surfaces formed from a material of higher corrosion-resistance than steel, eg. nickel-chrome.
There now follow detailed descriptions, to be read with reference to the accompanying drawings, of three disc brake systems which are illustrative of the present invention.
REFERENCES:
patent: 1933176 (1933-10-01), Jonsson
patent: 1959213 (1934-05-01), Nygard
patent: 2724252 (1955-11-01), Schmal
patent: 2737033 (1956-03-01), Bendall
patent: 2764261 (1956-09-01), Bridges
patent: 2926760 (1960-03-01), Lucien
patent: 3171515 (1965-03-01), Wolfe
patent: 3191735 (1965-06-01), Wavak
patent: 3233704 (1966-02-01), Strain et al.
patent: 3438464 (1969-04-01), Barrington
patent: 3630320 (1971-12-01), Lochmann
patent: 3631953 (1972-01-01), Snoy et al.
patent: 3642101 (1972-02-01), Hauth
patent: 3692148 (1972-09-01), Hauth
patent: 3754624 (1973-08-01), Eldred
patent: 3788436 (1974-01-01), Sugahara
patent: 3829260 (1974-08-01), Shimoda
patent: 3915272 (1975-10-01), Maurice
patent: 3934686 (1976-01-01), Stimson et al.
patent: 4000791 (1977-01-01), Kovac
patent: 4058190 (1977-11-01), Gardner et al.
patent: 4256209 (1981-03-01), Lupertz
patent: 4280597 (1981-07-01), Schorwerth
patent: 4296851 (1981-10-01), Pierce
patent: 4478324 (1984-10-01), Sink
patent: 4479569 (1984-10-01), Kummer et al.
patent: 4511021 (1985-04-01), Grider
patent: 4534457 (1985-08-01), Eltze et al.
patent: 4557356 (1985-12-01), Petersen
patent: 4576255 (1986-03-01), Méry et al.
patent: 4585096 (1986-04-01), Bok
patent: 4798268 (1989-01-01), Fargier et al.
patent: 4844206 (1989-07-01), Casey
patent: 4865160 (1989-09-01), Casey
patent: 5137374 (1992-08-01), Orkin
patent: 5310025 (1994-05-01), Anderson
patent: 5383538 (1995-01-01), Bair et al.
patent: 5390769 (1995-02-01), Bair et al.
patent: 5437351 (1995-08-01), Lindner
patent: 5520269 (1996-05-01), Yamamoto et al.
patent: 5851056 (1998-12-01), Hyde
patent: 6035978 (2000-03-01), Metzen et al.
patent: 2039003 (1971-02-01), None
patent: 2 039 003 (1971-02-01), None
patent: 2 451 104 (1976-05-01), None
patent: 96553 (1983-12-01), None
patent: 983548 (1965-02-01), None
patent: 1350350 (1974-04-01), None
patent: 2015122 (1979-09-01), None
patent: 2 150 263 (1985-06-01), None
patent: 2184801 (1987-07-01), None
patent: WO 94/02753 (1994-02-01), None
patent: WO 94/02753 (1994-03-01), None
patent: 70/5340 (1970-08-01), None
patent: 70/5340-A1 (1970-08-01), None
Delphi Technologies Inc.
Oberleitner Robert J.
Pezzlo Benjamin A.
Synnestvedt & Lechner LLP
LandOfFree
Disc brake system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Disc brake system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Disc brake system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2567643