PatentDe  


Dokumentenidentifikation EP1125771 18.10.2007
EP-Veröffentlichungsnummer 0001125771
Titel Reifengeräuschreduzierungsvorrichtung
Anmelder Sumitomo Rubber Industries Ltd., Kobe, Hyogo, JP
Erfinder Yukawa, Naoki, Kobe-shi, Hyogo-ken, JP;
Nakajima, Tokuzo, Kobe-shi, Hyogo-ken, JP;
Nishikawa, Masami, Kobe-shi, Hyogo-ken, JP;
Aoki, Chieko, Kobe-shi, Hyogo-ken, JP;
Sugihara, Hideaki, Kobe-shi, Hyogo-ken, JP
Vertreter Manitz, Finsterwald & Partner GbR, 80336 München
DE-Aktenzeichen 60036272
Vertragsstaaten DE, FR, GB
Sprache des Dokument EN
EP-Anmeldetag 21.12.2000
EP-Aktenzeichen 003115961
EP-Offenlegungsdatum 22.08.2001
EP date of grant 05.09.2007
Veröffentlichungstag im Patentblatt 18.10.2007
IPC-Hauptklasse B60C 19/00(2006.01)A, F, I, 20051017, B, H, EP

Beschreibung[en]

The present invention relates to a tyre noise reducing system, more particularly to an improved resonance damper disposed in a tyre hollow and secured to a wheel rim.

In recent years, as the mechanical noise from automobiles especially passenger cars is greatly reduced, the tyres especially passenger car tyres are strongly required to have reduced noise. There are many factors in tyre noise, but a circumferential resonance of the air in the annular tyre hollow is a major factor. That is, the ring of air inside the tyre which is continuous around the rim is excited by vibrations during running and resonates in the circumferential direction. Usually, a resonance peak occurs in a frequency range of from 50 to 400 Hz according to the tyre size.

In the published Japanese patent JP-B-7-14682 , an assembly of a wheel rim and a pneumatic tyre mounted thereon is disclosed, wherein a ball-like body which is made of rubber, sponge or the like is put in the annular tyre hollow to block the circumferential continuity thereof to control resonance.

Such a ball-like body is however, liable to disturb the high-speed rotational balance of the tyre because the inner surface of the tyre receives the full weight of the ball-like body which increases as the rotational speed increases. Further, it has a tendency to make it difficult to mount the tyre on a wheel rim.

EP 0 737 597 A1 describes a noise-reduction system for vehicle tyres according to the preamble of claim 1, comprising a wheel rim, a pneumatic tyre to be mounted on the wheel rim to form an annular tyre hollow, and a resonance damper to be disposed in the annular tyre hollow which is formed by flexible baffles being fixed to the rim at one of their ends.

US 4,392,522 discloses a tyre noise reducing system comprising noise absorbing means which are provided in the form of an open cell foam material inside a portion of the inner tyre volume. The noise absorbing means are fixed to the inner surface of the tyre or to the rim.

It is an object of the present invention to provide an improved tyre noise reducing system, in which resonance in the tyre hollow is controlled to reduce tyre noise without sacrificing the high-speed balance and rim-mounting operation.

This object is achieved with a tyre noise reducing system having the features of claim 1.

With the inventive tyre noise reducing system, the inner surface of the tyre receives none or only a part of the gravity and the high-speed rotational balance of the tyre becomes greatly improved.

The present invention will be described in detail in conjunction with the accompanying drawings:

  • Fig. 1 is a cross-sectional view of a system useful in understanding the present invention;
  • Figs. 2 and 3 are schematic sectional views each showing a tyre and a rim assembly taken along the tyre equator for showing examples of resonance dampers which are useful in understanding the present invention; and
  • Figs. 4 and 5 are sectional views each showing an example of an inventive resonance damper.

According to the present invention, a tyre noise reducing system 1 comprises a pneumatic tyre 2, a wheel rim 3a and a resonance damper 6.

In the drawings, the pneumatic tyre 2 is mounted on the wheel rim 3a and an annular closed hollow 4 is formed around the wheel rim 3a. The resonance damper 6 is disposed in the annular hollow 4.

The tyre 2 is a tubeless tyre comprising a tread portion 2T, a pair of sidewall portions 2S and a pair of bead portions 2B.

In this embodiment, the tyre 2 is a radial tyre for passenger cars.

The wheel rim 3a is provided around a disk 3b and they make up a wheel 3. The rim 3a comprises a pair of axially spaced bead seats on which the tyre bead portions 2B seat, a rim well between the bead seats, and a pair of flanges 10 each extending radially outwardly from one of the bead seats along the axially outer surface of the bead portion 2B.

The resonance damper 6 according to the present invention is made of a relatively thin flexible material and constructed to rise from the wheel rim 3a towards the tyre due to centrifugal force during running and thus to block the annular hollow 4.

For the resonance damper 6, various rubber-like solid materials, rubber-like porous materials, fibrous materials and the like can be used.

For the rubber-like solid materials, for example, diene rubbers such as natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene butadiene rubber (SBR), nitrile rubber (NBR), chloroprene rubber (CR) and the like can be used.

For the porous materials various sponge rubbers or foam rubbers of either closed-cell or open-cell foam can be used.

For the fibrous materials, non-woven fabric made of organic fibres such as felt, a kind of paper and the like can be used.

Preferably, foam rubbers, e.g. polyethylene foam and polyurethane foam are used.

In Fig.1 and Fig.2 which are not according to the invention, a loose band 5 is shown as an example of the resonance damper 6. The loose band 5 is a closed loop made of an elastic material and disposed around the wheel rim 3a. Thus it is secured to the wheel rim 3a.

The inside diameter D of the loose band 5 is set in a range of more than 1.02, preferably more than 1.07, more preferably more than 1.10 times the diameter Dr of the wheel rim 3a. But the inside diameter D is preferably less than 0.98, more preferably less than 0.96 times the inside diameter Di of the tyre measured at the tyre equator under such condition that the tyre is normally inflated but loaded with no tyre load.

In Fig.1, for the sake of convenience, the loose band 5 is illustrated as if it is a circle and floats between the tyre and rim coaxially with the tyre.

In the example shown in Fig.2, the loose band 5 is only put around the wheel rim 3a and is fixed to neither the tyre 2 nor the wheel 3. Therefore, in the annular hollow 4, the behaviour of the loose band 5 caused by a force F such as gravitation, centrifugal force etc. is such that a portion comes into contact with the wheel rim 3a but an opposite portion 5c comes into contact with or near the inner surface of the tread portion 2T as shown in Fig.2. These portions are not always a fixed portion. Their positions are changed according to the rotation as the loose band 5 is free. As a result, the loose band 5 divides the annular hollow 4 into uncertain parts for example two parts 4a and 4b in Fig.2. Accordingly, the occurrence of standing waves in fundamental harmonic and higher harmonics can be completely prevented.

On the other hand, in Fig.3 which shows a modification of the example shown in Fig.2, the loose band 5 is fixed to the wheel rim 3a at one point (A).

In Fig.4 further showing an inventive system , the loose band 5 is fixed to the wheel rim 3a at a plurality of points (A) so that portions 5c between the fixed points (A) are slacked. Usually, the fixed points (A) are provided evenly in the circumferential direction on both the loose band and the circumference of the rim 3a to form the slack portions 5c evenly around the wheel rim 3a.

Fig.5 shows another embodiment of the present invention wherein the resonance damper 6 is a slack strip 7 having a certain length and both ends 7a and 7b thereof are fixed to the wheel rim 3a and the portion 7c between the fixed points (A) is slacked.

In Fig.5, a single slack strip 7 is disposed, but it is also possible to provide two or more slack strips 7.

Therefore, the slacked portions 5c of the loose band 5s and the slacked portions 7c of the slack strip 7 are raised by centrifugal force F during running.

To fix the loose bands 5 in Figs.3 and 4 and the slack strip 7 on the wheel rim 3a, various adhesive agents, screws, bolts and the like may be used. Preferably, they are fixed to the bottom of the rim well so as not to interfere with tyre mounting. And for the same reason, the slack portion is folded during mounting the tyre.

In order to effectively block up the circumferential continuity of the annular hollow 4, the sizes of the slack portions 5c and 7c are set such that these portions rise up to a height Ha of at least 50%, preferably more than 70%, more preferably more than 100% (*1), still more preferably in a range of from 80 to 95 % of the section height of the annular hollow 4 {=(Di-Dr)/2}.

*1) The limitation "more than 100%" means that the portions can rise up beyond the section height if the tyre is removed. Thus, in the actual condition, it means that a certain area of the slack portion comes into contact with the inner surface of the tread portion as shown in Fig.3.

In a meridian section of the tyre under the normally inflated condition, the blockade area Sb or the cross sectional area of a part of the annular hollow which part is blocked by the rising slack portions 5c, 7c must be more than 30%, preferably more than 40% of the total sectional area Sa.

Therefore, in the case of the above-mentioned porous materials, the width BW is set in a range of not less than 20% of the maximum width W of the annular hollow 4, and the thickness is set in a range of from 2 to 30 mm, preferably 3 to 20 mm, more preferably 3 to 10 mm.

In the case of the rubber-like solid materials and fibrous materials, the width BW is set in a range of not less than 40%, preferably not less than 45%, more preferably 50 to 95% of the maximum width W, and the thickness is set in a range of from 0.5 to 6 mm, preferably 0.5 to 3 mm, more preferably 0.5 to 2 mm.

Comparison Tests Noise test

During coasting a Japanese 2000cc FR passenger car on a noise test course (rough asphalt road) at a speed of 60 km/hr, a total sound level at 226, 240 and 253 Hz was measured near the driver's ears. In Tables 1A, 1B and 1C, the results are indicated in dB using a difference from Ref.1.

Tyre size 195/65R15

Rim size 15X6JJ (Rim diameter 380.2 mm)

Tyre inflation pressure 200 KPa

Rim mounting test

The installation of the damper and the hand mounting operation of the tyre on the wheel under such a condition that the damper is already installed were evaluated by a skilled person. <u>Table 1A</u> Tyre Ref Ex.1 Ex.2 Ex.3 Ex.4 Ex.5 Ex.6 Ex.7 Ex.8 Ex.9 Damper - Fig.2 Fig.3 Fig.4 Fig.5 Fig.5 Fig.5 Fig.5 Fig.5 Fig.5 Material - rubber Rubber rubber rubber rubber rubber rubber rubber rubber Thickness (mm) - 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 Width BW(mm) - 110 110 110 110 110 110 140 80 110 BW/W(%) - 58 58 58 58 58 58 73 42 58 Loose band D(mm) - 446 446 477 - - - - - - D/Dr - 1.17 1.17 1.25 - - - - - - Slack strip Number - - - - 1 2 1 1 1 1 Rising height Ha(mm) - - - - 130 130 110 130 130 80 Ha/H(%)*1 - - - - 100 100 84 100 100 62 Sb/Sa(%)*2 - - - - 64 64 60 64 46 46 Noise (dB) 0 -4 -4.2 -1.4 -6.8 -7.9 -5 -7.2 -3.6 -3.5 Rim mounting good good Good good good no good good good good good
<u>Table 1B</u> Tyre Ex.10 Ex.11 Ex.12 Ex.13 Ex.14 Ex.15 Ex.16 Ex.17 Ex.18 Damper Fig.2 Fig.3 Fig.4 Fig.5 Fig.5 Fig.5 Fig.5 Fig.5 Fig.5 Material *3 sponge sponge Sponge sponge sponge sponge sponge sponge sponge Thickness (mm) 5 5 5 5 5 5 5 5 5 Width BW(mm) 110 110 110 110 110 110 140 80 110 BW/W(%) 58 58 58 58 58 58 73 42 58 Loose band D(mm) 446 446 477 - - - - - - D/Dr 1.17 1.17 1.25 - - - - - - Slack strip Number - - - 1 2 1 1 1 1 Rising height Ha(mm) - - - 130 130 110 130 130 80 Ha/H(%)*1 - - - 100 100 84 100 100 62 Sb/Sa(%)*2 - - - 64 64 60 64 46 46 Noise (dB) -5.7 -5.8 -6.2 -7.2 -8 -6 -7.7 -4.5 -5 Rim mounting good good Good good no good good good good good
<u>Table 1C</u> Tyre Ex.19 Ex.20 Ex.21 Ex.22 Damper Fig.2 Fig.2 Fig.2 Fig.2 Material *3 sponge sponge Sponge sponge Thickness (mm) 10 10 10 10 Width BW(mm) 110 90 70 50 BW/W(%) 58 47 37 26 Loose band D(mm) 446 446 446 446 D/Dr 1.17 1.17 1.17 1.17 Rising height Ha(mm) - - - - Ha/H(%) 1 - - - - Sb/Sa(%) 2 - - - - Noise (dB) -6.4 -4.8 -4 -3.6 Rim mounting good good Good good *1) Section height H =(Di-Dr)/2 of tyre annular hollow =130 mm

*2) Sectional area Sa of tyre annular hollow =189.8 sq.cm

*3) Polyurethane foam (Specific gravity 0.022)


Anspruch[de]
Reifengeräuschverminderungssystem, das umfasst: - eine Radfelge (3a), - einen Luftreifen (11) zum Aufziehen auf die Radfelge, um einen ringförmigen Reifenhohlraum (4) zu bilden, und - einen Resonanzdämpfer (6) zum Anordnen in dem ringförmigen Reifenhohlraum, dadurch gekennzeichnet, dass - der Dämpfer (6) eines von einem ringförmigen, elastischen, losen Band, das um die Felge herum angeordnet ist, und einem flexiblen, lockeren Streifen mit einer bestimmten Länge ist, und - der Dämpfer (6) an der Radfelge (3a) zumindest an zwei Punkten (A) befestigt ist, sodass ein Abschnitt (5c, 7c) zwischen den zwei befestigten Punkten (A) locker ist, wodurch der lockere Abschnitte (5c, 7c) während eines Laufes auf Grund einer Zentrifugalkraft angehoben wird, um den ringförmigen Reifenhohlraum zu blockieren. Reifengeräuschverminderungssystem nach Anspruch 1,

dadurch gekennzeichnet, dass

die maximale Anhebehöhe des lockeren Abschnitts zumindest 50 % der Querschnittshöhe des ringförmigen Hohlraumes beträgt.
Reifengeräuschverminderungssystem nach Anspruch 2,

dadurch gekennzeichnet, dass

die maximale Anhebehöhe des lockeren Abschnitts mehr als 70 % der Querschnittshöhe des ringförmigen Hohlraumes beträgt.
Reifengeräuschverminderungssystem nach Anspruch 3,

dadurch gekennzeichnet, dass

die maximale Anhebehöhe des lockeren Abschnitts mehr als 100 % der Querschnittshöhe des ringförmigen Hohlraumes beträgt.
Reifengeräuschverminderungssystem nach Anspruch 3,

dadurch gekennzeichnet, dass

die maximale Anhebehöhe (Ha) des lockeren Abschnitts in einem Bereich von 80 bis 95 % der Querschnittshöhe des ringförmigen Hohlraumes liegt.
Reifengeräuschverminderungssystem nach einem der Ansprüche 1 bis 5,

dadurch gekennzeichnet, dass

der Resonanzdämpfer aus einem gummiartigen, porösen Material hergestellt ist.
Reifengeräuschverminderungssystem nach einem der Ansprüche 1 bis 5,

dadurch gekennzeichnet, dass

der Resonanzdämpfer aus einem gummiartigen, kompakten Material hergestellt ist.
Reifengeräuschverminderungssystem nach einem der Ansprüche 1 bis 5,

dadurch gekennzeichnet, dass

der Resonanzdämpfer aus einem faserartigen Material hergestellt ist.
Reifengeräuschverminderungssystem nach einem der Ansprüche 1 bis 8,

dadurch gekennzeichnet, dass

der Resonanzdämpfer (6) eine Breite (BW) in einem Bereich von nicht weniger als 20 % der maximalen Breite des ringförmigen Reifenhohlraumes und eine Dicke in einem Bereich von 2 bis 30 mm aufweist.
Reifengeräuschverminderungssystem nach einem der Ansprüche 7 oder 8, wobei der Resonanzdämpfer eine Breite in einem Bereich von nicht weniger als 40 % der maximalen Breite des ringförmigen Reifenhohlraumes und eine Dicke in einem Bereich von 0,5 bis 6 mm aufweist. Reifengeräuschverminderungssystem nach einem der vorhergehenden Ansprüche,

dadurch gekennzeichnet, dass

der Dämpfer (6) an der Radfelge an zumindest drei Punkten (A) befestigt ist.
Reifengeräuschverminderungssystem nach einem der vorhergehenden Ansprüche,

dadurch gekennzeichnet, dass

der Dämpfer (6) aus einem Streifen (7) gebildet ist, der an der Radfelge (3a) an seinen beiden Enden befestigt ist.
Anspruch[en]
A tyre noise reducing system comprising - a wheel rim (3a), - a pneumatic tyre (11) to be mounted on the wheel rim to form an annular tyre hollow (4), and - a resonance damper (6) to be disposed in the annular tyre hollow, characterised in that - the damper (6) is one of an annular elastic loose band disposed around the rim and a flexible slack strip having a certain length, and - the damper (6) is fixed to the wheel rim (3a) at least at two points (A) so that a portion (5c, 7c) between the fixed points (A) is slack whereby the slack portion (5c, 7c) is raised by centrifugal force during running to block the annular tyre hollow. A tyre noise reducing system according to claim 1, characterised in that the maximum rising height of the slack portion is at least 50% of the section height of the annular hollow. A tyre noise reducing system according to claim 2, characterised in that the maximum rising height of the slack portion is more than 70% of the section height of the annular hollow. A tyre noise reducing system according to claim 3, characterised in that the maximum rising height of the slack portion is more than 100% of the section height of the annular hollow. A tyre noise reducing system according to claim 3, characterised in that the maximum rising height (Ha) of the slack portion is in a range of from 80 to 95 % of the section height of the annular hollow. A tyre noise reducing system according to any of claims 1 to 5, characterised in that the resonance damper is made of a rubber-like porous material. A tyre noise reducing system according to any of claims 1 to 5, characterised in that the resonance damper is made of a rubber-like solid material. A tyre noise reducing system according to any of claims 1 to 5, characterised in that the resonance damper is made of a fibrous material. A tyre noise reducing system according to any of claim 1 to 8, characterised in that the resonance damper (6) has a width (BW) in a range of not less than 20% of the maximum width of the annular tyre hollow, and a thickness in a range of from 2 to 30 mm. A tyre noise reducing system according to claim 7 or 8, wherein the resonance damper has a width in a range of not less than 40% of the maximum width of the annular tyre hollow, and a thickness in a range of from 0.5 to 6 mm. A tyre noise reducing system according to one of the preceding claims, characterized in that the damper (6) is fixed to the wheel rim at at least three points (A). A tyre noise reducing system according to anyone of the preceding claims, characterized in that the damper (6) is formed by a strip (7) fixed to the wheel rim (3a) at its both ends.
Anspruch[fr]
Système de réduction du bruit d'un bandage comprenant

une jante de roue (3a),

un bandage pneumatique (11) qui doit être monté sur la jante de roue pour former un creux de bandage annulaire (4), et

un amortisseur de résonance (6) qui doit être disposé dans le creux de bandage annulaire,

caractérisé en ce que

l'amortisseur (6) est un amortisseur composé d'une courroie lâche élastique annulaire disposée autour de la jante et d'une bande détendue flexible ayant une certaine longueur, et

l'amortisseur (6) est fixé à la jante de roue (3a) au moins au niveau de deux points (A) de façon à ce qu'une partie (5c, 7c) entre les points fixés (A) est détendue de sorte que la partie détendue (5c, 7c) est soulevée par la force centrifuge pendant la conduite pour bloquer le creux de bandage annulaire.
Système de réduction du bruit d'un bandage selon la revendication 1, caractérisé en ce que la hauteur d'élévation maximale de la partie détendue est au moins de 50 % de la hauteur de profilé du creux annulaire. Système de réduction du bruit d'un bandage selon la revendication 2, caractérisé en ce que la hauteur d'élévation maximale de la partie détendue est supérieure à 70 % de la hauteur de profilé du creux annulaire. Système de réduction du bruit d'un bandage selon la revendication 3, caractérisé en ce que la hauteur d'élévation maximale de la partie détendue est supérieure à 100 % de la hauteur de profilé du creux annulaire. Système de réduction du bruit d'un bandage selon la revendication 3, caractérisé en ce que la hauteur d'élévation maximale (Ha) de la partie détendue se trouve dans une plage allant de 80 à 95 % de la hauteur de profilé du creux annulaire. Système de réduction du bruit d'un bandage selon l'une quelconque des revendications 1 à 5, caractérisé en ce que l'amortisseur de résonance est fabriqué dans un matériau poreux similaire à du caoutchouc. Système de réduction du bruit d'un bandage selon l'une quelconque des revendications 1 à 5, caractérisé en ce que l'amortisseur de résonance est fabriqué dans un matériau solide similaire à du caoutchouc. Système de réduction du bruit d'un bandage selon l'une quelconque des revendications 1 à 5, caractérisé en ce que l'amortisseur de résonance est fabriqué dans un matériau fibreux. Système de réduction du bruit d'un bandage selon l'une quelconque des revendications 1 à 8, caractérisé en ce que l'amortisseur de résonance (6) a une largeur (BW) dans une plage d'au moins 20 % de la largeur maximale du creux de bandage annulaire, et une épaisseur dans une plage allant de 2 à 30 mm. Système de réduction du bruit d'un bandage selon la revendication 7 ou 8, dans lequel l'amortisseur de résonance a une largeur dans une plage d'au moins 40 % de la largeur maximale du creux de bandage annulaire, et une épaisseur dans une plage allant de 0,5 à 6 mm. Système de réduction du bruit d'un bandage selon l'une quelconque des revendications précédentes, caractérisé en ce que l'amortisseur (6) est fixé à la jante de roue au niveau d'au moins trois points (A). Système de réduction du bruit d'un bandage selon l'une quelconque des revendications précédentes, caractérisé en ce que l'amortisseur (6) est formé par une bande (7) fixée à la jante de roue (3a) au niveau de ses deux extrémités.






IPC
A Täglicher Lebensbedarf
B Arbeitsverfahren; Transportieren
C Chemie; Hüttenwesen
D Textilien; Papier
E Bauwesen; Erdbohren; Bergbau
F Maschinenbau; Beleuchtung; Heizung; Waffen; Sprengen
G Physik
H Elektrotechnik

Anmelder
Datum

Patentrecherche

Patent Zeichnungen (PDF)

Copyright © 2008 Patent-De Alle Rechte vorbehalten. eMail: info@patent-de.com