DE102018113974A1 - Torsional vibration damper with sliding cups made of sintered material - Google Patents

Abstract

The invention relates to a torsional vibration damper (1) of an internal combustion engine driven vehicle, comprising a primary mass (2) and a secondary mass, which can be rotated against the resistance of arc springs (3) which are curved towards an axis of rotation, ends of the primary mass (2) and the secondary mass in each case are connected to an arc spring (3) which is greased, supported and guided in the circumferential direction via its outer diameter on a sliding shell (7) used in a spring chamber (5) and designed as a half-shell, the anti-wear element forming the arc spring (3) Sliding shell (7) is made of a sintered material.

Description

The invention relates to a torsional vibration damper of a vehicle powered by an internal combustion engine, comprising a primary mass and a secondary mass, which are rotatable against the resistance of curved to a rotational axis bow springs, wherein at ends of the masses located drivers are each associated with a bow spring and the bow springs in the circumferential direction on their Outer diameter are supported and guided on a sliding shell. The invention further relates to two methods for producing such sliding plates used in torsional vibration dampers.

A well-known two-mass flywheel (DMF) and generally known torsional vibration damper is used for damping torsional vibrations or torsional vibrations in drive trains of internal combustion engine-powered vehicles. Due to combustion processes of the reciprocating internal combustion engine, a rotational nonuniformity occurs which, transmitted to the drive train of the vehicle, leads to a loss of comfort. The torsional vibration damper dampens the vibrations emanating from the internal combustion engine, prevents transmission to the drive train of the vehicle and thus improves driving comfort.

From the DE 10 2009 039 997 A1 as well as the DE 10 2011 015 637 A1 For example, torsional vibration dampers are known, which are used in the drive train of a vehicle whose primary mass and secondary mass are arranged relatively rotatable against the resistance of bow springs. The bow springs are supported by wear protection elements forming sliding shells, which partially enclose the bow springs on the outside and are rotationally fixed in position on the primary mass. If the bow springs, which are preferably designed as helical compression springs, are compressed by the angular momentum in the operating state of the torsional vibration damper, then the individual turns of the bow springs move on the associated sliding shell, resulting in friction. Depending on the speed and the centrifugal forces that occur, a comparatively large, wear-increasing friction can be established.

The invention has for its object to provide a wear-resistant and friction-optimized and weight-optimized sliding shell, which avoids inlet effects and is inexpensive to produce.

This problem is solved according to the invention by the features of claim 1 and by the method according to claims 8 to 10. Further preferred embodiments or developments of the invention can be found in the subclaims, the description and the associated figures.

According to the invention it is provided according to claim 1, that one, a wear protection element for the bow spring and a spring chamber wall of the primary mass of the torsional vibration damper forming sliding shell is made of a sintered material. Due to the sintering process, the sintered material, which is also called sintered metal, which consists of fine-grained metallic substances, forms a solid component, the sliding shell. By means of the temperature treatment of the sintering, the sliding shell receives its final properties such as hardness and strength.

The sliding shell produced by a sintering process possesses a certain porosity due to the sintered material consisting of metal particles or metal powder, which advantageously makes it possible to absorb lubricant and consequently leads to a friction optimization of the tribological system of the ZMS or torsional vibration damper consisting of the bow springs, sliding shells and the lubricating grease. The comparison with known tribosystems adjusting, reduced friction leads to the avoidance or to a significantly reduced wear on contact zones of the sliding shells and bow springs. At the same time can be increased with the measure according to the invention, the fatigue life or durability of the grease used in the bow spring assembly.

Furthermore, with the concept according to the invention even in the new state already a low coefficient of friction of the tribological system can be realized, which avoids a negative run-in effect, which improves, for example, only after a certain mileage of the vehicle or neutralized.

The sintering process makes it possible to manufacture the sliding shell without chipping and without forming. The product, a standardized slip bowl, can thus be manufactured ready for installation without any subsequent treatment or waste. In addition, the production of sliding shells with relatively short throughput times can be achieved by sintering, so that even high batch sizes with low production costs are environmentally friendly and energy-poor to produce. Furthermore, sintering provides an optimum surface texture, also called surface roughness. This corresponds to the surfaces of previous, made of solid materials sliding plates in which the surfaces or contact surfaces were machined by grinding and subsequent fine turning.

With the sliding cup produced according to the invention from a sintered material, a friction-optimized torsional vibration damper can be represented which furthermore has improved vibration isolation and reduced component wear. By means of the sintering applied, a sliding cup can be produced with a high degree of accuracy, dimensional accuracy and a small tolerance band level, with predetermined dimensional tolerances being reliably maintained even for large batches.

The microporosity of the sintered metal advantageously leads to a low mass of the finished sliding shell. Compared with a sliding shell made with solid material, a weight advantage of> 5 to ≤ 25% can thus be realized. Thus, if necessary, necessary adjustments in design can be compensated for sliding cups made of sintered metal, which lead to an increase in weight compared to previous designs. In addition, due to the internal porosity of the sintered part, a desired advantageous vibration damping occurs.

According to an advantageous embodiment of the invention, it is provided to introduce a heat-dissipating material in the sintering material selection intended for the sliding shell. As an embedded material for admixing is preferably copper or aluminum, with which an effective heat dissipation of the sliding shell can be achieved. In addition or as an alternative, the sintered metal mixture may include a material optimizing the lubrication and consequently reducing the friction. In particular, molybdenum, which is introduced into the sintered metal powder before the compression, which is also referred to as pressing, and in addition to the heat treatment, is suitable for this purpose. With this measure, advantageously over the entire life of the torsional vibration damper, a tribosystem with a reduced coefficient of friction and with increased wear resistance.

As an alternative or in addition to an admixture, it is provided according to the invention to immerse the sliding shell completely in an impregnation medium, for example oil, immediately after the heat treatment. To achieve a different, or a desired, selectively adjustable friction between the bow spring and the inner Gleitschalenkrümmung the sliding shell can alternatively be partially immersed in the circumferential direction in oil. Due to the relatively large porosity, a suction effect occurs when the sintered metal is immersed in oil, forming a permanent lubricating film on the surface. Preference is given to using a friction minimizing and corrosion-avoiding, preferably suitable additives including impregnating medium. Furthermore, a suitable additive can be used as the impregnation medium, which ensures sufficient lubrication already in the new, unrestrained state of the torsional vibration damper. A different friction is also achieved by a targeted admixture of solid lubricants (FKSS) during sintering along the inner Gleitschalenkrümmung, so that deliberately sets a lower or higher friction in certain areas between the bow spring and the sliding shell.

The sliding shells made of sintered metal can also be designed as complex moldings or in different designs. For example, sliding shells can be used with a radially outer flat contact surface. By a over the entire width of the sliding shell extending flat contact surface, a large-scale reinforced back, which increases the breaking strength of the sliding significantly. This conception also leads to a secure, improved support and positional fixation of the sliding shell in the installed state, for which also advantageously set constant friction conditions. As a measure for weight optimization, it makes sense to produce a waisted sliding shell which forms a recess locally on both sides.

Furthermore, sliding shells made from a sintered material can be structurally adapted to specific installation situations and can consequently be integrated into existing ZMS concepts.

According to a preferred arrangement, the sliding shell made of sintered metal is inserted in a spring space of the bow spring arrangement of the torsional vibration damper. The spring chamber is on the drive side and the outside of the primary mass and the output side limited by a lid connected to the primary mass. The bow springs are each enclosed by designed as half shells sliding cups, which are supported radially on the outside of the primary mass.

• - Bereitstellen von feinkörnigen oder pulvrigen metallischen Stoffen, die vermischt einem Sinterprozess zugeführt werden;
• - daran schließt sich das Sintern, ein Verdichten der metallischen Stoffe an, wobei mittels Erwärmung bzw. einer Wärmebehandlung die metallischen Ausgangsstoffe zur Herstellung der Gleitschale zusammengebacken werden.

The present invention further provides a method for producing a sliding shell on which bow springs of a torsional vibration damper are supported and guided, comprising the following method steps:

• - Providing fine-grained or powdery metallic materials, which are mixed fed to a sintering process;
• - This is followed by sintering, a densification of the metallic substances, wherein by means of heating or a heat treatment, the metallic starting materials for the production of the sliding shell are zusammengebacken.

• - Bereitstellen von feinkörnigen oder pulvrigen metallischen Stoffen, denen zur Erreichung einer gezielten, einstellbaren Reibung zwischen den Bogenfedern und der Gleitschale entlang der inneren Gleitschalenkrümmung geeignete Festkörperschmierstoffe (FKSS) beigemischt sind und alle Sintermaterialien vermischt einem Sinterprozess zugeführt werden, alternativ oder ergänzend können zur Erreichung einer wunschgemäßen, definierten Wärmeabfuhr ebenso geeignete Sintermaterialien zugefügt werden;
• - daran schließt sich das Sintern, ein Verdichten der metallischen Sintermaterialien an, wobei mittels Erwärmung bzw. einer Wärmebehandlung die metallischen Ausgangsstoffe zur Herstellung der Gleitschale zusammengebacken werden.

According to claim 9, a method for producing a sliding shell is provided, are supported and guided on the bow springs of a torsional vibration damper, comprising the following steps:

• - Provision of fine-grained or powdery metallic materials which are mixed to achieve a targeted, adjustable friction between the bow springs and the sliding along the inner Gleitschalenkrümmung suitable solid lubricants (FKSS) and all sintered materials are fed to a sintering process mixed, alternatively or additionally, to achieve a desired, defined heat removal as suitable sintered materials are added;
• - This is followed by the sintering, a densification of the metallic sintered materials, wherein by means of heating or a heat treatment, the metallic starting materials are caked together for the production of the sliding shell.

• - Bereitstellen von feinkörnigen oder pulvrigen metallischen Stoffen, denen zur Optimierung der Schmierung und eines Einlaufverhaltens geeignete Materialien beigemischt sind und alle Sintermaterialien vermischt einem Sinterprozess zugeführt werden;
• - daran schließt sich das Sintern, ein Verdichten der metallischen Sintermaterialien an, wobei mittels Erwärmung bzw. einer Wärmebehandlung die metallischen Ausgangsstoffe zur Herstellung der Gleitschale zusammengebacken werden;
• - abschließend wird die Gleitschale vollständig oder teilweise zur Erreichung einer wunschgemäßen, gezielt einstellbaren Reibung zwischen den Bogenfedern und der Gleitschale entlang der inneren Gleitschalenkrümmung in Umfangsrichtung in ein Imprägnierungsmedium, beispielsweise Öl oder ein geeignete Additive einschließendes Medium eingetaucht.

According to claim 10, a method for producing a sliding shell is provided, are supported and guided on the bow springs of a torsional vibration damper, comprising the following steps:

• - Provision of fine-grained or powdery metallic materials, which are mixed to optimize the lubrication and run-in behavior suitable materials and all sintered materials are mixed fed to a sintering process;
• - This is followed by sintering, a densification of the metallic sintered materials, wherein by means of heating or a heat treatment, the metallic starting materials for the production of the sliding shell are baked together;
• - Finally, the sliding is completely or partially immersed to achieve a desired, specifically adjustable friction between the bow springs and the sliding along the inner Gleitschalenkrümmung in the circumferential direction in an impregnation medium, for example, oil or a suitable additives enclosing medium.

According to the invention, the methods for selectively influencing the friction in defined zones of the sliding shell, in particular the inner Gleitschalenkrümmung, be carried out separately or combined.

• 1: einen Ausschnitt eines Drehschwingungsdämpfers mit einer erfindungsgemäßen Gleitschale;
• 2: eine Gleitschale als Einzelteil mit einer äußeren, ebenen Außenkontur.

In the following, the invention will be shown with reference to two embodiments, which are described in more detail below. However, the invention is not limited to the exemplary embodiments shown. It shows:

• 1 a section of a torsional vibration damper with a sliding shell according to the invention;
• 2 : a sliding shell as an individual part with an outer, flat outer contour.

The 1 shows a partial section or a partial view of a two-mass flywheel called torsional vibration damper 1 used in a power train of a vehicle (not shown) between an internal combustion engine and a friction clutch. The torsional vibration damper 1 includes internal combustion engine side, also referred to as an input part primary mass 2 and on the output side a, also called output part secondary mass (not shown). The primary mass 2 and the secondary mass are over a bow springs 3 enclosing, a spring damper forming bow spring assembly 4 connected and rotatable about an axis of rotation (not shown) rotatable and limited relative to each other. The one hand on the primary mass 2 and on the other hand on the secondary mass supported bow springs 3 are in a spring room 5 introduced, the drive side and the outside of the primary mass 2 and on the output side of a cohesive to the primary mass 2 attached lid 6 is limited. A relative twisting of the secondary mass compared to the primary mass 2 takes place counter to a spring force direction of the bow springs 3 ,

The torsional vibration damper 1 closes as wear protection between the primary mass 2 and the spring elements forming bow springs 3 several sliding cups 7 on. The sliding shells designed as half-shells 7 surround radially on the outside the bow springs 3 and are at the same time inside on the primary mass 2 supported and guided. The torsional vibration damper 1 includes circumferentially several separately positioned sliding cups 7 , which are produced according to the invention in one piece from a sintered material. Each partially encircling, preferably semi-circular sliding shell 7 extends on the outside almost over the entire length of a bent curved bow spring in the installed state 3 , Here are the bow springs 3 in the shell-shaped cross-sectional profile of the sliding shells 7 positively received and at the same time non-positively due to a biasing force on a contact surface 8th supported. For fixing the position in the spring chamber 5 can the slip bowl 7 For example, include guide tabs (not shown), the form-fitting in corresponding openings of the primary mass 2 intervention.

The 2 shows the slip bowl 17 , the radially outside a flat, over the entire width the slip bowl 17 extending contact surface 9 having. This is the slip bowl 17 large area and safe in the primary mass 2 supported.

LIST OF REFERENCE NUMBERS

1

torsional vibration dampers

2

primary mass

3

bow spring

4

Arch spring assembly

5

spring chamber

6

cover

7

sliding

8th

contact area

9

outer contour

17

sliding

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

• DE 102009039997 A1 [0003]
• DE 102011015637 A1 [0003]

Claims (10)

Torsional vibration damper (1) of an internal combustion engine-driven vehicle, comprising a primary mass (2) and a secondary mass, which are rotatable counter to the resistance of bow springs (3) pre-curved to an axis of rotation, wherein ends of the primary mass (2) and the secondary mass each comprise a bow spring ( 3) are connected, which in the circumferential direction over its outer diameter on a in a spring chamber (5) inserted, designed as a half shell sliding shell (7, 17) greased, supported and guided, characterized in that a wear protection element of the bow spring (3) forming Sliding tray (7, 17) is made of a sintered material. Torsional vibration damper after Claim 1 , characterized in that in the sintered material of the sliding shell (7, 17) a heat dissipating material is incorporated. Torsional vibration damper according to one of the preceding claims, characterized in that in the sintered material of the sliding shell (7, 17) a lubrication and the friction improving material is incorporated. Torsional vibration damper according to one of the preceding claims, characterized in that after a heat treatment, immersion of the sliding shell (7, 17) is provided in an impregnation medium. Torsional vibration damper according to one of the preceding claims, characterized in that the sliding shell (17) via a flat outer contour (9) in the spring chamber (5) is supported. Torsional vibration damper according to one of the preceding claims, characterized in that the bow springs (3) are guided on waisted sliding shells (7, 17). Torsional vibration damper according to one of the preceding claims, characterized in that the sliding shell (7, 17) in the spring chamber (5) is inserted, the drive side and on the outside of the primary mass (2) and the output side of a primary mass (2) connected to the lid ( 6) is limited. Method for producing a sliding shell (7, 17) on which bow springs (3) of a torsional vibration damper (1) are supported and guided, comprising the following method steps: - Providing fine-grained or powdery metallic materials, which are mixed fed to a sintering process; - Sintering, in which by compaction of the metallic sintered materials and by heating or a heat treatment, the starting materials for producing the sliding shell (7, 17) are baked together. Method for producing a sliding shell (7, 17) on which bow springs (3) of a torsional vibration damper (1) are supported and guided, comprising the following method steps: - Provision of fine-grained or powdery metallic materials, which are mixed to achieve a targeted, adjustable friction between the bow springs and the sliding shell along the inner Gleitschalenkrümmung suitable solid lubricants (FKSS); Alternatively or additionally, suitable sintering materials can be added to achieve a desired, defined heat dissipation; - Sintering, in which by compaction of the metallic sintered materials and by heating or a heat treatment, the starting materials for producing the sliding shell (7, 17) are baked together. Method for producing a sliding shell (7, 17) on which bow springs (3) of a torsional vibration damper (1) are supported and guided, comprising the following method steps: - Provision of fine-grained or powdery metallic materials, which are mixed to optimize the lubrication and running-in behavior suitable materials and all sintered materials are mixed fed a sintering process; - This is followed by the sintering, a densification of the metallic sintered materials, wherein by means of heating or a heat treatment, the metallic starting materials for producing the sliding shell (7, 17) are baked together; - Finally, the sliding shell (7, 17) completely or partially immersed to achieve a desired, specifically adjustable friction between the bow springs and the sliding along the inner Gleitschalenkrümmung in the circumferential direction in an impregnation medium, such as oil or a suitable additives enclosing medium.

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