DE102009044079A1 - Drive belt e.g. motor vehicle V-belt, has angulated flanks completely forming force transfer zone, where flank angle of flanks of V-belt and flank angle of flanks of drive ribs of V-ribbed belt amount to greater than or equal to 65 degree - Google Patents

Abstract

The belt has flexible base bodies comprising a cover layer as a belt rear side and a base layer, which is provided with a group of drive ribs (20). Angulated flanks (21, 22) completely form a force transfer zone. Flank angle of flanks of a V-belt and flank angle (beta) of the former flanks of the drive ribs of the V-ribbed belt (19) amount to greater than or equal to 65 degree. The V-belt comprises a flexible base body such as cured rubber mixture or rubber component, and a traction cord made of polyethylentherephthalate or polyamide is embedded into the base body of the V-belt.

Description

• – Keilriemens mit einem elastischen keilförmigen Grundkörper, dessen beiden gewinkelten Flanken die Kraftübertragungszone bilden;

oder eines

• – Keilrippenriemens mit einem elastischen Grundkörper, umfassend eine Decklage als Riemenrücken sowie einen Unterbau, der mit einer Gruppe von Keilrippen versehen ist, wobei die gewinkelten Flanken sämtlicher Keilrippen die Kraftübertragungszone bilden.

The invention relates to a drive belt in the form of a

• - V-belt with an elastic wedge-shaped body whose two angled flanks form the power transmission zone;

or one

• - V-ribbed belt with an elastic body, comprising a cover layer as a belt back and a substructure, which is provided with a group of V-ribs, wherein the angled edges of all V-ribs form the power transmission zone.

Drive belts, also referred to as power transmission belts, may be formed as flat belts, V-belts, V-ribbed belts and toothed belts. However, the present invention relates exclusively to the V-belt and V-ribbed belt, reference being made in this regard in particular to the following patent literature:

fan belt

• EP 0 662 571 B1

V-ribbed belts

• DE 38 23 157 A1
• DE 100 16 351 A1
• DE 10 2006 007 509 A1
• EP 0 590 423 A2
• EP 0 737 228 B1
• EP 0 831 247 B1
• EP 0 866 834 B1
• EP 1 108 750 A1
• EP 1 129 308 B1
• WO 03/043922 A1
• US 3,981,206
• US 5 026 327
• US 2003/0121729 A1

As this document overview shows, the development focus is on the field of V-ribbed belts.

V-ribbed belts (KRR) for automotive applications and the predecessors used mainly in the industrial sector, the V-belts (KR), transmit frictional torques over the wedge flanks. Compared to flat belts, the surface pressure in the two belt types mentioned above is higher for geometrical reasons. A KR and KRR can therefore transmit more power than flat belts without the belt slipping too much. The smaller the flank angle, the more power can be transmitted. However, too small flank angles (<38 °) in combination with small discs can lead to pinching of the wedge or ribs and thus to the destruction of the belts. For a KR and KRR therefore a flank angle of 40 ° +/- 2 ° is the norm, with particular reference to the DIN 7867 is referenced. In V-ribbed belt drives it can easily come to unwanted chattering noises due to the compact design with disc misalignments in operation. This is avoided in a shaped KRR by a friction coefficient lowering coating. However, a coating is expensive and expensive. In addition, the coating wears with increasing mileage on aggressive engines. In a grinding KRR also fibers, such as aramid fibers are mixed into the sub-base mix, which also lower the coefficient of friction of the drive belt. This, too, leads to an increase in the production costs, since it takes a great deal of mixing work to achieve an acceptable fiber distribution. In addition, the preferred textile fibers themselves are relatively expensive. The fibers are particularly effective when they stick out of the wedge flanks. According to experience, however, they break off after a short period of time, as a result of which the noise behavior deteriorates.

In summary, the following should be noted: In the national and international standards, the smallest possible flank angle was included to ensure maximum surface pressure and transmission capability. For reasons of noise but at the same time the friction with expensive measures must be reduced again. From this point of view, it seems much easier to dispense with these measures, in the context of a new flank angle philosophy.

In the patent US 5 026 327 a KRR with a flank angle of about 60 ° is described. Experiments had shown, however, that with this angular magnification compared to a KRR with a flank angle of about 40 °, no basis for a concept change is given, which led to this path being abandoned.

In the publications US 2003/0121729 A1 and WO 03/043922 A1 For example, KRR having an increased flank angle, for example 90 °, is described from the viewpoint of an elevator belt. However, the dryness that can occur in automotive applications does not play a significant role in elevator belts. This is due to the fact that in elevator belts there are normally no discs of small diameters (<65 mm) chosen, which are common as generator discs in a motor vehicle (usually 50 mm to 60 mm). In addition, a less compact arrangement of the discs is selected in elevators, which is not possible disc misalignment as in a car to dry noise problems (chirping noises) lead.

In the background of the problem and conflict situation mentioned above, especially in the motor vehicle sector, the new KR and the KRR are characterized in that the flank angle α of the two flanks of a KR and the flank angle β of the two flanks of each V-rib of a KRR is ≥ 65 ° ,

The preferred flank angles α and β are ≥ 70 °, in particular ≥ 75 °, in particular again ≥ 80 °, but ≦ 90 °. A test series has shown that with a flank angle of 80 ° to 85 °, in particular at 85 °, the best results are achieved.

The KR and KRR in conjunction with the new angle concept have a preferred belt height of 3.2 mm to 4.8 mm, in particular of 3.6 mm to 4.4 mm. So far belt heights of 4.4 mm to 5.2 mm are usual.

For a KRR, the pitch is preferably 3 mm to 4 mm. So far, it is 3.56 mm.

The drive belt, in particular the KRR, is used as a vehicle belt.

The preferred materials for the elastic body of a KR and KRR are presented in more detail in the description of the embodiments.

• – Es können weniger aufwendige Unterbaumischungen, insbesondere für einen Schleif-KRR, verwendet werden, da keine Fasern eingemischt und homogen verteilt werden müssen.
• – Auf eine aufwendige und teure Beschichtung, insbesondere für einen Form-KRR, kann verzichtet werden.
• – Es kann ein konstanter Reibbeiwert erzielt werden, auch nach Abrieb.
• – Es tritt keine Klemmwirkung auf, die den Bewegungsablauf beeinträchtigt und zu einer Zerstörung des Riemens führt.
• – Wenn man die Flankenfläche konstant lässt, kann die Riemenhöhe abgesenkt werden, insbesondere, wenn man von einem Flankenwinkel von 40° auf einen Flankenwinkel von 85° geht. Dies reduziert den Materialeinsatz weiter und erhöht zusätzlich die Lebensdauer, insbesondere bei einem KRR.

The following advantages are associated with this novel angle concept for a KR and KRR:

• - Less complex sub-mixes, especially for a grinding KRR, can be used, as no fibers have to be mixed in and distributed homogeneously.
• - On a complex and expensive coating, especially for a shape KRR, can be dispensed with.
• - It can be achieved a constant coefficient of friction, even after abrasion.
• - There is no clamping action that affects the movement and leads to a destruction of the belt.
• - If you leave the flank area constant, the belt height can be lowered, especially if you go from a flank angle of 40 ° to a flank angle of 85 °. This further reduces the use of materials and additionally increases the service life, especially for a KRR.

The invention will now be explained by means of exemplary embodiments with reference to schematic drawings. Show it:

1 a KR having a flank angle α according to the prior art;

2 a KR with a flank angle α according to the invention;

3 a KRR in two versions A and B according to the prior art;

4 a KRR with a flank angle β according to the invention.

1 shows a KR 1 with an elastic wedge-shaped basic body 2 whose two angled flanks 3 and 4 form the power transmission zone. The flank angle α is 40 ° here. According to the prior art, the two flanks are provided in particular with an abrasion-resistant and noise-reducing coating ( EP 0 662 751 B1 ).

2 also shows a KR 5 with an elastic wedge-shaped basic body 6 comprising the two angled flanks 7 and 8th as a power transmission zone. However, the flank angle α is 85 ° here. At this wide angle of a KR can be dispensed with a coating. In addition, compared to the KR 1 to 1 a reduction of the belt height can be realized.

3 shows a KRR 9 with an elastic base body, comprising a cover layer 10 as a belt back and a substructure 11 that with a group of V-ribs 12 is provided, with the angled flanks 13 and 14 all V-ribs 12 form the power transmission zone.

In the body is at least one running in the belt longitudinal tensile strand 16 embedded. In most cases form several parallel Zugstränge 16 , in particular in the form of individual cords, a reinforcement layer 15 , The tensile strand consists of polyethylene terephthalate (PET), polyamide (PA), in particular PA6.6 again, or polyethylene-2,6-naphthalate (PEN). This tension cord concept can also be used for a KR 1 and 2 come into use.

Within the power transmission zone is the KRR 9 with a flock coating 17 (Section A), for example made of cotton or aramid, or with a textile cover 18 (Section B), for example in the form of a woven, knitted or knitted fabric provided. In this regard, reference is made to the above cited state of KRR technology.

4 now shows angle technical details of the V-ribs 20 of the KRR 19 , The angled flanks 21 and 22 all V-ribs 20 here have a flank angle β of also 85 °. At a such wide angle can be on the coating 17 or 18 ( 3 ) are waived.

The elasticity including the bending elasticity of a KR and a KRR is achieved in that the base body and thus the cover layer and the substructure in a KRR consist of a polymeric material with elastic properties, in which case the two material groups elastomers and thermoplastic elastomers (TPE) to call.

In particular, the polymeric material is a vulcanized rubber composition containing at least one rubber component and blend ingredients. As the rubber component, ethylene-propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), (partially) hydrogenated nitrile rubber (HNBR), fluororubber (FKM), natural rubber (NR), chloroprene rubber (CR), butadiene Rubber (BR) or styrene-butadiene rubber (SBR), which are uncut or blended with at least one other rubber component, in particular with one of the aforementioned rubber types, for example in the form of an EPM / EPDM or SBR / BR blend. Of particular importance is CR or EPM or EPDM or an EPM / EPDM blend. The mixture ingredients thereby comprise at least one crosslinker or a crosslinker system (crosslinking agent and accelerator). Other mixing ingredients are usually still a filler and / or a processing aid and / or a plasticizer and / or an aging inhibitor and optionally further additives, such as fibers and color pigments. In this regard, reference is made to the general state of rubber mixing technology.

LIST OF REFERENCE NUMBERS

1

V-belt (KR)

2

elastic wedge-shaped body

3

flank

4

flank

5

V-belt (KR)

6

elastic wedge-shaped body

7

flank

8th

flank

9

V-ribbed belt (KRR)

10

Cover layer (strap back) as part of the elastic body

11

Substructure as part of the elastic body

12

V-rib

13

flank

14

flank

15

Reinforcement layer

16

tension cord

17

Flock edition

18

textile wraps

19

V-ribbed belt (KRR)

20

V-rib

21

flank

22

flank

α

Flank angle KR

β

Flank angle KRR

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 0662571 B1 [0002]
• DE 3823157 A1 [0002]
• DE 10016351 A1 [0002]
• DE 102006007509 A1 [0002]
• EP 0590423 A2 [0002]
• EP 0737228 B1 [0002]
• EP 0831247 B1 [0002]
• EP 0866834 B1 [0002]
• EP 1108750 A1 [0002]
• EP 1129308 B1 [0002]
• WO 03/043922 A1 [0002, 0007]
• US 3,981,206 [0002]
• US 5026327 [0002, 0006]
• US 2003/0121729 A1 [0002, 0007]
• EP 0662751 B1 [0020]

Cited non-patent literature

• DIN 7867 [0004]

Claims (20)

Drive belt in the form of a V-belt ( 1 . 5 ) with an elastic wedge-shaped basic body ( 2 . 6 ), whose two angled flanks ( 3 . 4 . 7 . 8th ) form the power transmission zone; or a V-ribbed belt ( 9 . 19 ) with an elastic base body ( 10 . 11 ), comprising a cover layer ( 10 ) as a belt back and a substructure ( 11 ) with a group of V-ribs ( 12 . 20 ), wherein the angled flanks ( 13 . 14 . 21 . 22 ) of all V-ribs ( 12 . 20 ) form the power transmission zone; characterized in that the flank angle (α) of the two flanks ( 3 . 4 . 7 . 8th ) of a V-belt ( 1 . 5 ) and the flank angle (β) of the two flanks ( 13 . 14 . 21 . 22 ) each V-rib ( 12 . 20 ) of a V-ribbed belt ( 9 . 19 ) ≥ 65 °. Drive belt according to claim 1, characterized in that the flank angle (α, β) ≥ 70 °. Drive belt according to claim 2, characterized in that the flank angle (α, β) ≥ 75 °. Drive belt according to claim 3, characterized in that the flank angle (α, β) ≥ 80 °. Drive belt according to one of claims 1 to 4, characterized in that the flank angle ≤ 90 °. Drive belt according to claim 4 or 5, characterized in that the flank angle (α, β) is 80 ° to 85 °. Drive belt according to claim 6, characterized in that the flank angle (α, β) is 85 °. Drive belt according to one of claims 1 to 7, characterized in that the belt height is 3.2 mm to 4.8 mm. Drive belt according to claim 8, characterized in that the belt height is 3.6 mm to 4.4 mm. Drive belt according to one of claims 1 to 9, characterized in that the drive belt in the form of a V-ribbed belt has a pitch of 3 mm to 4 mm. Drive belt according to one of claims 1 to 10, characterized in that the elastic base body ( 2 . 6 ) is a vulcanized rubber composition containing at least one rubber component as well as compounding ingredients. Drive belt according to claim 11, characterized in that the rubber component is ethylene-propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), (partially) hydrogenated nitrile rubber (HNBR), chloroprene rubber (CR), fluorine rubber (FKM), natural rubber (NR), styrene-butadiene rubber (SBR) or butadiene rubber (BR), which are used uncut or in admixture with at least one further rubber component, in particular in combination with one of the abovementioned rubber types. Drive belt according to claim 12, characterized in that the rubber component is CR or EPM or EPDM or an EPM / EPDM blend. Drive belt according to one of claims 1 to 13, characterized in that in the main body of the V-belt ( 1 . 5 ) or V-ribbed belt ( 9 . 19 ) at least one running in the belt longitudinal tensile strand ( 16 ) is embedded. Drive belt according to claim 14, characterized in that the tension cord ( 16 ) consists of polyethylene terephthalate (PET). Drive belt according to claim 14, characterized in that the tension cord ( 16 ) consists of polyamide (PA). Drive belt according to claim 16, characterized in that the tension cord ( 16 ) consists of PA6.6. Drive belt according to claim 14, characterized in that the tension cord ( 16 ) consists of polyethylene-2,6-naphthalate (PEN). Drive belt according to one of claims 1 to 18 for use as a motor vehicle belt. Drive belt according to claim 19 for use as a motor vehicle V-ribbed belt.

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