GB2093936A - Disc brake - Google Patents
Disc brake Download PDFInfo
- Publication number
- GB2093936A GB2093936A GB8204776A GB8204776A GB2093936A GB 2093936 A GB2093936 A GB 2093936A GB 8204776 A GB8204776 A GB 8204776A GB 8204776 A GB8204776 A GB 8204776A GB 2093936 A GB2093936 A GB 2093936A
- Authority
- GB
- United Kingdom
- Prior art keywords
- friction ring
- bell
- disc
- brake
- shaped
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000007423 decrease Effects 0.000 claims abstract description 3
- 230000008878 coupling Effects 0.000 abstract description 4
- 238000010168 coupling process Methods 0.000 abstract description 4
- 238000005859 coupling reaction Methods 0.000 abstract description 4
- 230000006378 damage Effects 0.000 abstract description 2
- 238000005336 cracking Methods 0.000 abstract 1
- 238000001816 cooling Methods 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 230000008646 thermal stress Effects 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 238000005266 casting Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
- 230000035882 stress Effects 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D65/00—Parts or details
- F16D65/02—Braking members; Mounting thereof
- F16D65/12—Discs; Drums for disc brakes
- F16D65/128—Discs; Drums for disc brakes characterised by means for cooling
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D65/00—Parts or details
- F16D65/0006—Noise or vibration control
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D65/00—Parts or details
- F16D65/02—Braking members; Mounting thereof
- F16D65/12—Discs; Drums for disc brakes
- F16D65/123—Discs; Drums for disc brakes comprising an annular disc secured to a hub member; Discs characterised by means for mounting
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D65/00—Parts or details
- F16D65/02—Braking members; Mounting thereof
- F16D2065/13—Parts or details of discs or drums
- F16D2065/1304—Structure
- F16D2065/1316—Structure radially segmented
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D65/00—Parts or details
- F16D65/02—Braking members; Mounting thereof
- F16D2065/13—Parts or details of discs or drums
- F16D2065/1304—Structure
- F16D2065/1328—Structure internal cavities, e.g. cooling channels
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D65/00—Parts or details
- F16D65/02—Braking members; Mounting thereof
- F16D2065/13—Parts or details of discs or drums
- F16D2065/134—Connection
- F16D2065/1348—Connection resilient
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D65/00—Parts or details
- F16D65/02—Braking members; Mounting thereof
- F16D2065/13—Parts or details of discs or drums
- F16D2065/134—Connection
- F16D2065/1356—Connection interlocking
- F16D2065/1368—Connection interlocking with relative movement both radially and axially
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Braking Arrangements (AREA)
Abstract
A brake disc (1) for a disc brake is composed integrally of a friction ring (2) and a bell-shaped disc portion (3). To reduce deformation, as for instance warping of the disc surface or torsion of the friction ring (2) and the bell- shaped disc portion (3), the coupling of the friction ring (2) to the bell- shaped disc portion (3) is designed elastically within limits, so that the deformation and tension caused thereby will be removed at this point and the danger of cracking and possible destruction of the brake disc (1) resulting therefrom will be reduced. The bell-shaped disc portion (3) includes for this purpose axial slots (10) which form webs (12) whose cross-section decreases towards the friction ring (2). <IMAGE>
Description
SPECIFICATION
Disc brake
This invention relates to a brake disc for a disc
brake of the kind which is composed of a friction
ring and a bell-shaped disc portion extending in
the direction of the axis of rotation for non
rotatable engagement between the friction ring
and an element to be braked, which bell-shaped
portion includes webs at its end close to the
friction ring, these webs having several axially
extending slots, carrying at their ends the friction
ring and having a varying cross-section
throughout their length.
Brake discs of the kind referred to are
employed in brakes subjected to high thermal and
mechanical stresses, wherein jamming may occur
between the friction ring and the bell-shaped
portion as a result of thermal expansion of the friction riny, for example. Such jamming can
cause deformation of the disc surface and torsion
of the friction ring and/or bell-shaped portion.
Local overheating will ensue and result in cracks
which may end in the destruction of the brake
disc. In addition, there is the danger of axial
movement being blocked in the case of a brake
disc which is designed to be axially slidable.
A brake disc is described in British Patent
Specification No. 1,133,1 10 wherein the friction
ring is connected to the bell-shaped portion by fasteners such as screws, for example, At the end
of the bell-shaped disc portion close to the friction
ring are axially directed slots which delineate a
number of fingers spread over the periphery.
These fingers are angled off at their free end and
coupled to the friction ring. The other end of the
fingers is delineated by bores in the bell-shaped
portion, these bores representing the end of the
slots and having a diameter larger than the slot
width; the fingers have a smaller cross-section in
this end area than in the end area which lies close
to the friction ring.
By arranging the fingers in the end area of the
bell-shaped disc portion, a radial flexibility is
produced in this area. Because of the end of the slots being formed by a bore with larger diameter, -the finger will be particularly yielding in this area
of smaller cross-section, the latter laying in the
extension of the bell-shaped portion, so that
deformations which are caused by, for instance,
thermal expansion of the friction ring will be
compensated for predominantly in this area.In the area of the transition bell-shaped disc
portion/friction ring, the fingers are less yielding because of the larger cross-section, the angled-off shape and the screw coupling, and, as a result, due to the rigidity at this point, the torsions between the bell-shaped disc portion and the friction ring are removed only to an incomplete degree, and the tension caused is transmitted to the bell-shaped portion in a disadvantageous
manner. It has to be regarded as a further disadvantage that an undesired heat flow.
takes place almost unhinderedly between the
friction ring and the bell-shaped disc portion as a result of the slot width being small in relation to the circumference of the bell-shaped portion.
It is an object of the present invention to provide a brake disc of the kind initially referred to which, for the purpose of reduction of deformations and torsions, is elastic within limits in the area where the bell-shaped disc portion is articulated to the friction ring, and wherein thermal stresses are minimized.
According to the invention in its broadest aspect, a brake disc for a disc brake of the kind referred to is characterized in that the friction ring and the bell-shaped disc portion are formed integrally and in that the cross-section of the webs decreases towards the friction ring.
By virtue of the inventive construction, the coupling of the bell-shaped portion of the disc to the friction ring is elastic within limits. This has as a consequence a reduction of the high rigidity of the arrangement friction ring/bell-shaped disc portion in this area so that elastic compensating movements of the friction ring are possible; thus, deformations and warpings as well as the tension resulting therefrom will be reduced in a favourable manner. In a particularly expedient way, this ensures the axial slidability of the floatingly-arranged brake disc.The shape of the webs having a smaller cross-section at the point of articulation prevents the bell-shaped portion of the disc from being excessively heated up due to the passing of heat from the brake ring onto the bell-shaped disc portion and thereby avoids the disadvantage of the slidability being impaired.
In a favourable manner, the thermal stresses exerted on the disc are reduced by arranging for radially extending cooling-air ducts to be accommodated in the interior of the friction ring; in addition to this, the flow of air through the cooling'air ducts is improved by the slots which form further intake ports for the air flow.
The webs may be spread over the circumference of the bell-shaped portion at a different distance from one another or, alternatively, the slots may be of different dimensions. Such an asymmetric arrangement of the webs or varying the dimensions of the slots accomplishes a reduction of brake noise in a very simple way by partial elimination of the vibrations caused.
Embodiments of the invention will now be described by way of example with reference to the accompanying drawings, in which:
Figure 1 is a view of a disc brake incorporating a first slot shape,
Figure 2 is a section taken along the line lI-li in Figure 1,
Figure 3 is a development of the bell-shaped disc portion having slot openings of different design, with the slot openings having differing dimensions and distances one from the other.
In Figures 1 and 2, reference numeral 1 designates the brake disc of a brake unit, the disc being composed of a friction ring 2 and a bellshaped disc portion 3. The friction ring 2 comprises two axially-spaced friction discs 4 and
5 which are interconnected by radialiy-extending
ribs 6. The ribs 6 form cooling-air ducts 7 for
cooling the brake disc 1 by ventilation and are
curved like vanes in a manner (not shown) for
achieving good flow conditions. The friction ring 2
is formed from a casting integrally with the
tubular bell-shaped disc portion 3 that extends in
the direction of the axis of rotation. At its end
remote from the friction ring 2, the bell-shaped
disc portion 3 has a collar 8 which is provided
with several bores 9 permitting the brake disc 1
to be fastened in a rotation-preventing manner.A
large number of slots 10 which extend axially and
are scattered over the periphery is arranged at the
bell-shaped disc portion 3. The slots 10 extend
from an unslotted area 11 of the bell-shaped disc
portion 3, adjacent the collar 8, to the friction ring
2 and increase in width continuously; this
provides a large number of axially-extending webs
12 along the circumference of the bell-shaped
disc portion 3, these webs having their smaliest
cross-section at the transition from the bell
shaped disc portion 3 to the friction ring 2. The
webs 12 extend in an axial direction up to the
friction disc 5.
When viewing the development of the bell
shaped disc portion, the slots are designed
approximately trapezoidally, with the larger
trapeze base line being located at the friction ring
2. In the embodiment according to Figure 1, the
smaller trapeze base line is rounded in a circular
manner so that the slot 10 has almost the shape
of a V. Because of the webs 12 having the
smallest cross-section in the point of articulation
between the friction ring 2 and the bell-shaped
disc portion 3, there is formed a coupling of the
bell-shaped disc portion 3 to the friction ring 2
which is elastic within limits.
Figure 3 shows the development of the
circumference of the bell-shaped disc portion. In this embodiment, the trapezoidal slots 10 are not
spread over the circumference equi-distantly, but have slightly varying distances from each other, e.g. the distances X, Y. Further, it can be seen that the axial depth of the slots 10, for instance relative to one another, also differs by the amount
S.
A reduction of brake noise will be achieved in that the bell-shaped element is asymmetrical and, therefore, has bad oscillating properties.
In another embodiment (not shown), each web 12 terminates beneath a cooling-air duct 7, and its end is designed as a guide surface for the air flow.
Claims (5)
1. Brake disc for a disc brake of the kind which is composed of a friction ring and a bell-shaped disc portion extending in the direction of the axis of rotation for non-rotatable engagement between the friction ring and an element to be braked, which beli-shaped portion includes webs at its end close to the friction ring, these webs having several axially extending slots, carrying at their ends the friction ring and having a varying cross-section throughout their length, characterized in that the friction ring (2) and the bell-shaped disc portion (3) are formed integrally and in that the cross-section of the webs (12) decreases towards the friction ring (2).
2. Brake disc as claimed in claim 1, characterized in that the friction ring (2) accommodates in its interior radially extending cooling-air ducts (7).
3. Brake disc as claimed in claim 1 or 2, characterized in that the webs (12) are spread over the circumference of the bell-shaped portion (3) at a different distance from one another.
4. Brake disc as claimed in any one of the preceding claims, characterized in that there are provided slots (10) of different dimensions.
5. Brake disc for a disc brake substantially as described with reference to the accompanying drawings.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19813107124 DE3107124A1 (en) | 1981-02-26 | 1981-02-26 | BRAKE DISC FOR A DISC BRAKE |
Publications (2)
Publication Number | Publication Date |
---|---|
GB2093936A true GB2093936A (en) | 1982-09-08 |
GB2093936B GB2093936B (en) | 1984-09-19 |
Family
ID=6125756
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB8204776A Expired GB2093936B (en) | 1981-02-26 | 1982-02-18 | Disc brake |
Country Status (5)
Country | Link |
---|---|
BR (1) | BR8200988A (en) |
DE (1) | DE3107124A1 (en) |
FR (1) | FR2500553A1 (en) |
GB (1) | GB2093936B (en) |
IT (1) | IT1190697B (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0143264A1 (en) * | 1983-10-01 | 1985-06-05 | Schwäbische Hüttenwerke Gesellschaft mit beschränkter Haftung | Disc brake and mould and method for manufacturing such a disc brake. |
EP1245852A2 (en) * | 2001-03-20 | 2002-10-02 | Bayerische Motoren Werke Aktiengesellschaft | Vehicle disc brake |
US6722478B2 (en) | 2000-11-10 | 2004-04-20 | Bayerische Motoren Werke Aktiengesellschaft | Assembly for vehicle brake disk |
CN100559040C (en) * | 2004-09-16 | 2009-11-11 | 乔治费希尔汽车技术有限公司 | The brake disc assembly of automotive wheel |
US7677368B2 (en) | 2004-06-04 | 2010-03-16 | Brembo S.P.A. | Apparatus for controlling the coning in a brake rotor |
US8720654B2 (en) | 2009-04-09 | 2014-05-13 | Bayerische Motoren Werke Aktiengesellschaft | Brake disc pot for motor vehicles |
US20190093719A1 (en) * | 2015-07-24 | 2019-03-28 | Ap Racing Limited | Disc brakes and braking systems |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3805994A1 (en) * | 1988-02-25 | 1989-09-07 | Bayerische Motoren Werke Ag | DISC BRAKE FOR A MOTOR VEHICLE |
DE3942651C1 (en) * | 1989-12-22 | 1991-07-18 | Bayerische Motoren Werke Ag, 8000 Muenchen, De | Cooling air passage for disc brake - has air flow aperture in brake cover, and inner, peripheral, air guide protrusion |
FR2675221B1 (en) * | 1991-04-09 | 1993-06-11 | Renault Vehicules Ind | BRAKE DISC FORMING A ROTATING HUB. |
DE19505014A1 (en) * | 1995-02-15 | 1996-08-22 | Teves Gmbh Alfred | Brake disc for use in disc brake assembly |
DE19843399A1 (en) * | 1998-09-22 | 2000-03-23 | Volkswagen Ag | Brake disc for disc brakes |
DE19929391B4 (en) * | 1999-06-28 | 2011-01-13 | Saf-Holland Gmbh | brake disc |
DE19943893A1 (en) * | 1999-09-14 | 2001-03-15 | Continental Teves Ag & Co Ohg | Brake disc |
SE531202C2 (en) * | 2006-09-13 | 2009-01-13 | Scania Cv Abp | Brake disc and vehicle |
DE102008047625B4 (en) * | 2008-09-17 | 2015-04-30 | Knorr-Bremse Systeme für Nutzfahrzeuge GmbH | Internally ventilated brake disc |
FR3049999B1 (en) * | 2016-04-08 | 2019-06-21 | Peugeot Citroen Automobiles Sa | ALLEGE BRAKE DISC |
DE102016117008A1 (en) | 2016-09-09 | 2018-03-15 | Gigant - Trenkamp & Gehle Gmbh | Hub flange with attached brake disc assembly |
DE102017130290B4 (en) * | 2017-12-18 | 2022-04-28 | Saf-Holland Gmbh | brake disc |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1211041B (en) * | 1963-11-26 | 1966-02-17 | Teves Kg Alfred | Brake disc with a pot-shaped hub |
DE1480319B2 (en) * | 1965-03-17 | 1977-03-31 | ROTATING FRICTION BODY OF A FRICTION BRAKE | |
GB1133110A (en) * | 1966-06-30 | 1968-11-06 | Girling Ltd | Improvements in or relating to disc brakes |
FR1488139A (en) * | 1966-08-01 | 1967-07-07 | Budd Co | Rotor for disc brakes |
DE1630304A1 (en) * | 1967-06-24 | 1971-06-03 | Daimler Benz Ag | Brake disc for motor vehicles, especially internally cooled, provided with cooling blades |
DE1625827C3 (en) * | 1967-09-20 | 1975-04-24 | Alfred Teves Gmbh, 6000 Frankfurt | Ventilated brake disc with two friction rings |
DE2110482A1 (en) * | 1971-03-05 | 1972-09-14 | Porsche Kg | Internally ventilated brake disc |
DE2128594C3 (en) * | 1971-06-09 | 1980-08-07 | Zahnraederfabrik Renk Ag, 8900 Augsburg | Liquid-cooled, dry-running full-lined single-disc brake |
DE2557649C2 (en) * | 1975-12-20 | 1985-10-03 | Schwäbische Hüttenwerke GmbH, 7080 Aalen | Brake disc |
GB1587825A (en) * | 1976-12-11 | 1981-04-08 | Girling Ltd | Discs for disc brakes |
DE2901349A1 (en) * | 1978-01-20 | 1979-07-26 | Kawasaki Heavy Ind Ltd | CRUSH-PROOF BRAKE DISC FOR VEHICLE BRAKES |
-
1981
- 1981-02-26 DE DE19813107124 patent/DE3107124A1/en active Granted
-
1982
- 1982-01-08 FR FR8200206A patent/FR2500553A1/en active Granted
- 1982-02-18 GB GB8204776A patent/GB2093936B/en not_active Expired
- 1982-02-24 IT IT19817/82A patent/IT1190697B/en active
- 1982-02-25 BR BR8200988A patent/BR8200988A/en unknown
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0143264A1 (en) * | 1983-10-01 | 1985-06-05 | Schwäbische Hüttenwerke Gesellschaft mit beschränkter Haftung | Disc brake and mould and method for manufacturing such a disc brake. |
US6722478B2 (en) | 2000-11-10 | 2004-04-20 | Bayerische Motoren Werke Aktiengesellschaft | Assembly for vehicle brake disk |
EP1245852A2 (en) * | 2001-03-20 | 2002-10-02 | Bayerische Motoren Werke Aktiengesellschaft | Vehicle disc brake |
EP1245852A3 (en) * | 2001-03-20 | 2003-03-12 | Bayerische Motoren Werke Aktiengesellschaft | Vehicle disc brake |
US7677368B2 (en) | 2004-06-04 | 2010-03-16 | Brembo S.P.A. | Apparatus for controlling the coning in a brake rotor |
CN100559040C (en) * | 2004-09-16 | 2009-11-11 | 乔治费希尔汽车技术有限公司 | The brake disc assembly of automotive wheel |
US8720654B2 (en) | 2009-04-09 | 2014-05-13 | Bayerische Motoren Werke Aktiengesellschaft | Brake disc pot for motor vehicles |
US20190093719A1 (en) * | 2015-07-24 | 2019-03-28 | Ap Racing Limited | Disc brakes and braking systems |
Also Published As
Publication number | Publication date |
---|---|
IT8219817A0 (en) | 1982-02-24 |
DE3107124C2 (en) | 1988-06-23 |
GB2093936B (en) | 1984-09-19 |
FR2500553A1 (en) | 1982-08-27 |
FR2500553B1 (en) | 1985-02-22 |
IT1190697B (en) | 1988-02-24 |
BR8200988A (en) | 1983-01-04 |
DE3107124A1 (en) | 1982-09-09 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19930218 |