Strut mount unit for a motor vehicle

Abstract

A strut bearing unit (1) for a motor vehicle is disclosed, comprising a lower shell (2) designed to support a suspension spring, an upper shell (3) designed to couple with an upper mounting providing a connection to a chassis of the motor vehicle, a bearing (4, 5, 6) inserted between the upper shell (3) and the lower shell (2), wherein the strut bearing unit (1) comprises an inner sealing element (7) and an outer sealing element (8) that are separate from each other, each sealing element (7, 8) being received by a specific sealing seat provided by the upper shell (3) and / or the lower shell (2).

Description

Technical field

[0001] The present invention relates to a strut bearing unit for a motor vehicle according to the preamble of claim 1. Background of the invention

[0002] A motor vehicle suspension system comprises a strut that supports an axle and a wheel of a vehicle. A strut bearing unit, or suspension bearing unit, is located in the upper part of the strut, opposite the wheel and the ground, between a suspension spring and an upper element, the so-called upper mounting, which is either integral to the vehicle chassis or can be attached to it. Such a strut bearing unit is suitable for transmitting axial forces between the strut and the vehicle chassis. The strut bearing unit consists of a lower shell and an upper shell, with a bearing located between the lower and upper shells.

[0003] In current suspension systems, the bearing must be sealed by a mostly complicated or delicate and therefore expensive sealing unit in order to provide an internally and externally sealed strut bearing unit.

[0004] It is therefore an object of the present invention to provide a strut bearing unit that enables a simplified and cost-effective seal. Summary of the invention

[0005] This problem is solved by a strut bearing unit for a motor vehicle according to claim 1.

[0006] The strut mount, also called the suspension bearing unit, can be of the MacPherson type (so-called MacPherson suspension bearing unit). As described above, the strut mount can be located in the upper part of the strut, opposite the wheel and the ground, between a suspension spring and an upper element, hereinafter referred to as the upper mount. The upper mount can either be integral with the vehicle chassis or attached to the vehicle chassis.

[0007] The strut bearing assembly comprises a lower shell designed to support the suspension spring, an upper shell designed to couple with the upper mounting which provides a connection to a vehicle chassis, and a bearing inserted between the upper shell and the lower shell.

[0008] The strut mount assembly comprises an inner and an outer sealing element, which are separate from each other. Each sealing element is received by a specific sealing seat provided by the upper and / or lower shell. Because the sealing elements can be inserted into the strut mount assembly separately, handling and arrangement of the sealing elements is simplified compared to previous sealing elements, which were large and therefore complicated to install. The sealing elements described here offer a simple and cost-effective way to create an internal and external seal for the strut mount assembly and can be easily incorporated into a suitable manufacturing process.

[0009] According to one embodiment, the inner and outer sealing elements are provided as axial and / or radial seals. In the case of a radial seal, the sealing element is compressed primarily in the radial direction. If the sealing element is an axial seal, the compression occurs primarily in the direction of installation. This allows the seal to be individually adapted to specific requirements and conditions. The advantages of an axial seal are low friction, small installation width, long service life, and favorable production costs. The advantages of a radial seal are reduced friction and therefore a long service life, good resistance to oils, lubricants, greases, and hydraulic fluids, and suitability for high pressures at low speeds.Depending on customer requirements, the type of sealing element can be selected, thus providing flexibility to adapt to the specific requirements of the application. Furthermore, only one sealing element could be used, or the sealing elements could be supplemented with additional sealing elements.

[0010] According to a further embodiment, one or more grooves are provided in the upper shell and / or the lower shell in which the inner sealing element and / or the outer sealing element are arranged. The advantage of one or more grooves is that the inner and / or outer sealing element can be easily arranged in the strut bearing unit and held in a specific position.

[0011] Preferably, the one or more grooves have a rectangular and / or trapezoidal cross-sectional shape. This allows the one or more grooves to be optimally adapted to the inner and / or outer sealing element or the type of seal used. Furthermore, such a groove shape can be easily manufactured.

[0012] According to a further embodiment, centering diameters are provided in the upper and / or lower shell, which form a chamber for the inner and / or outer sealing element. In particular, the inner and / or outer sealing element can be clamped or pressed between the centering diameters of the upper and / or lower shell. Such an arrangement offers the advantage of simple manufacturing, since the upper and / or lower shell can be formed accordingly during production, and no additional step of producing grooves or other sealing seats is required.

[0013] According to a further embodiment, the inner sealing element and / or the outer sealing element overlaps with the upper shell and / or the lower shell. This ensures a reliable and stable connection between the sealing element(s) and the contact surfaces of the upper shell and / or the lower shell, thus guaranteeing an optimal seal between the sealing element and the lower or upper shell.

[0014] According to another embodiment, the inner and / or outer sealing element comprises a lubricant that reduces frictional torque, or the inner and / or outer sealing element is made of a material with reduced frictional torque. The advantage of this is to ensure a long-lasting seal. For example, the inner and / or outer sealing element can be made of fluoroelastomer or polytetrafluoroethylene. The lubricant can be silicone-based and / or can be grease or oil.

[0015] According to another embodiment, the inner and / or outer sealing element is manufactured in the form of a ring, for example, an O-ring or any other shape such as a four-lobed ring, or an injection seal. Designing the inner and / or outer sealing element in the form of a ring or an injection seal offers the advantage that, for example, a single O-ring can replace a radial and axial lip seal system. Thus, the design of the inner and / or outer sealing element can be simplified compared to existing sealing elements, which have a more complex structure and design. Furthermore, there is a direct connection between sealing compression and frictional torque, which can be easily adjusted and controlled.

[0016] The inner sealing element and / or the outer sealing element can be made, for example, from nitrile butadiene rubber, hydrogenated nitrile butadiene rubber, fluororubber, ethylene propylene, butyl, silicone, fluorosilicone, fluorocarbon, nitrile, chloroprene, polyacrylic, polytetrafluoroethylene or any other type of polymer or rubber.

[0017] The ring can be a standard solid (O)ring or a strip-cut (O)ring, where the ring is cut to size and fitted during the assembly of the strut mount unit. Alternatively, the injection-molded seal can be added during or prior to the manufacturing process. The injection-molded seal can be made of, for example, polyurethane, self-lubricating material, or TPS-SEBS (thermoplastic elastomer-styrene-ethylene-butylene copolymer).

[0018] According to a further embodiment, the upper shell and / or the lower shell have a projection extending towards and opposite the inner and / or outer sealing element. The projection can be triangular in shape. It can extend completely or partially along the area to be sealed. The projection, which is preferably in direct contact with the inner and / or outer sealing element, can ensure a reliable fit and arrangement of the respective sealing element. This can be achieved, for example, by pressing the respective sealing element onto the corresponding contact surface (i.e., the lower and / or the upper shell or the groove provided in the lower and / or upper shell) by means of the projection.This can further improve the sealing function, so that nothing can penetrate the strut bearing unit from the outside or escape from the strut bearing unit from the inside, for example lubricant from the seal or from the bearing.

[0019] Further preferred embodiments are defined in the dependent claims, as well as in the description and the figures. Elements described or shown in combination with other elements may be present alone or in combination with other elements without deviating from the scope of protection. Brief character description

[0020] Preferred embodiments of the invention are described below with reference to the drawings, which are only exemplary and are not intended to limit the scope of protection. The scope of protection is defined exclusively by the accompanying claims.

[0021] The figures show: Fig. 1: A first embodiment of a strut bearing unit in a side sectional view, Fig. 2: A second embodiment of the strut bearing unit in a side section view, Fig. 3: a third embodiment of the strut bearing unit in a side section view and Fig. 4: A fourth embodiment of the strut bearing unit in a side section view. Detailed description of the invention

[0022] In the following, identical or similarly functioning elements are marked with the same reference symbols.

[0023] Fig. 1, Fig. 2, Fig. 3 to Fig. Figures 4 each show a different embodiment of a strut bearing unit 1 in a side-sectional view with a lower shell 2 and an upper shell 3. Each shell 2, 3 can have the general shape of a cylindrical ring. A bearing is arranged between the lower shell 2 and the upper shell 3, comprising an inner ring 4, an outer ring 5, and rolling elements 6 inserted between the inner ring 4 and the outer ring 5. The bearing can be a rolling bearing, for example a ball bearing, but can also be any other type of bearing, such as a plain bearing or a roller bearing. The strut bearing unit 1, as shown in Figure 4, is shown in Figure 4. Fig. 1, Fig. 2, Fig. 3 to Fig. The upper shell 3, as shown in Figure 4, comprises an inner sealing element 7 and an outer sealing element 8. The upper shell 3 can be coupled to the chassis of a motor vehicle (not shown), and the lower shell 4 comprises a connecting part 12 for coupling to the suspension spring of the motor vehicle (not shown).

[0024] Fig. Figure 1 shows a first embodiment of the strut bearing unit 1 in a side-sectional view, wherein the inner sealing element 7 and the outer sealing element 8 are each provided as radial seals. Centering diameters 10 are provided in the upper shell 3 and the lower shell 2, each forming a chamber for the inner sealing element 7 and the outer sealing element 8. These chambers function as sealing seats that hold the inner sealing element 7 and the outer sealing element 8 in a predetermined position between the lower shell 2 and the upper shell 3, the position being defined by the centering diameters 10 provided in the lower shell 2 and the upper shell 3. The inner sealing element 7 and the outer sealing element 8 are here manufactured in the form of an O-ring.

[0025] Fig. Figure 2 shows a second embodiment of the strut bearing unit 1 in a side-sectional view, wherein the inner sealing element 7 and the outer sealing element 8 are each provided as axial seals. Grooves 9 are provided in the lower shell 2 as sealing seats in which the inner sealing element 7 and the outer sealing element 8 are arranged. Here too, the inner sealing element 7 and the outer sealing element 8 are manufactured in the form of an O-ring. Alternatively, the sealing elements 7, 8, or one of the sealing elements 7, 8, could be formed by injection molding, creating an injection seal. In this case, the material of the sealing element(s) 7, 8 could be injected directly into the respective groove 9.

[0026] Furthermore, the upper shell 3 comprises two projections 13, each extending in the direction of the inner sealing element 7 and the outer sealing element 8 and positioned opposite them. In the example shown here, the projections 13 have a triangular cross-section. However, it should be noted that the projections 13 can have any suitable shape, for example, a rectangular shape. It should also be noted that the projections 13 can extend continuously in the circumferential direction or can consist of several separate elements in the circumferential direction.

[0027] Fig. Figure 3 shows a third embodiment of the strut bearing unit 1 in a side-sectional view, wherein the inner sealing element 7 is provided as a radial seal and the outer sealing element 8 as an axial seal. Centering diameters 10 are provided in the upper shell 3 and the lower shell 2, forming a chamber for the inner sealing element 7. These chambers function as sealing seats that hold the inner sealing element 7 in a predetermined position between the lower shell 2 and the upper shell 3, the position being defined by the centering diameters 10 provided in the lower shell 2 and the upper shell 3. Grooves 9 are provided in the lower shell 2 as sealing seats in which the outer sealing element 8 is arranged. In the example shown here, the projections 13 have a triangular cross-section.It should be noted, however, that the projections 13 can have any suitable shape, for example, a rectangular shape. The inner sealing element 7 and the outer sealing element 8 are also manufactured in the form of an O-ring.

[0028] Fig. Figure 4 shows a fourth embodiment of the strut bearing unit 1 in a side-sectional view, wherein the inner sealing element 7 is provided as an axial seal and the outer sealing element 8 as a radial seal. Thus, it shows the third embodiment of the strut bearing unit according to Fig.3 in an opposite arrangement. Therefore, centering diameters 10 are provided in the upper shell 3 and the lower shell 2, forming a chamber for the outer sealing element 8. These chambers function as sealing seats that hold the outer sealing element 8 in a predetermined position between the lower shell 2 and the upper shell 3, the position being defined by the centering diameters 10 provided in the lower shell 2 and the upper shell 3. For the axial seal, a groove 9 is provided in the lower shell 2, which serves as a sealing seat and in which the outer sealing element 8 is arranged. The inner sealing element 7 and the outer sealing element 8 are also manufactured in the form of an O-ring. Alternatively, the sealing elements 7, 8, or one of the sealing elements 7, 8, could be formed by injection molding, creating an injection seal.In this case, the material of the sealing element(s) 7, 8 could be injected directly into the respective groove 9.

[0029] Furthermore, the upper shell 3 includes a cantilever 13 that extends towards the outer sealing element 8 and is positioned opposite it. In the example shown here, the cantilever 13 has a triangular cross-section. However, it should be noted that the cantilever 13 can have any suitable shape, for example, a rectangular shape.

[0030] In summary, a strut bearing unit is provided with an inner sealing element and an outer sealing element that are separate from each other, with each sealing element being received by a specific sealing seat provided by the upper shell and / or the lower shell, allowing for a simplified and cost-effective seal for a strut bearing unit for a motor vehicle. Reference symbol list 1 strut bearing unit 2 Lower bowl 3 Upper bowl 4 inner ring 5 outer ring 6 rolling elements 7 Inner sealing element 8 Outer sealing element 9 Nut 10 centering diameters 12 Connecting part lower shell 13 Cantilever

Claims

Strut mounting unit (1) for a motor vehicle, comprising a lower shell (2) designed to support a suspension spring, an upper shell (3) designed to couple with an upper mounting providing a connection to a chassis of the motor vehicle, a bearing (4, 5, 6) inserted between the upper shell (3) and the lower shell (2), characterized in that the strut mounting unit (1) comprises an inner sealing element (7) and an outer sealing element (8) that are separate from each other, each sealing element (7, 8) being received by a specific sealing seat provided by the upper shell (3) and / or the lower shell (2). Strut bearing unit according to claim 1, wherein the inner sealing element (7) and the outer sealing element (8) are provided as an axial seal and / or a radial seal. Strut bearing unit according to claim 1 or 2, wherein one or more grooves (9) are provided in the upper shell (3) and / or the lower shell (2) in which the inner sealing element (7) and / or the outer sealing element (8) are arranged. Strut bearing unit according to claim 3, wherein the one or more grooves (9) have a rectangular and / or trapezoidal cross-sectional shape. Strut bearing unit according to claim 1 or 2, wherein centering diameters (10) are provided in the upper shell (3) and / or the lower shell (2) which provide a chamber for the inner sealing element (7) and / or the outer sealing element (8). Strut bearing unit according to one of the preceding claims, wherein the inner sealing element (7) and / or the outer sealing element (8) overlaps with the upper shell (3) and / or the lower shell (2). Strut bearing unit according to one of the preceding claims, wherein the inner sealing element (7) and / or the outer sealing element (8) comprises a lubricant for reducing the frictional torque. Strut bearing unit according to one of the preceding claims, wherein the inner sealing element (7) and / or the outer sealing element (8) is made of a material with a reduced frictional torque. Strut bearing unit according to one of the preceding claims, wherein the inner sealing element (7) and / or the outer sealing element (8) is made in the form of an O-ring or an injection seal, preferably made of nitrile butadiene rubber, hydrogenated nitrile butadiene rubber, fluororubber or polytetrafluoroethylene. Strut bearing unit according to one of the preceding claims, wherein the upper shell (3) and / or the lower shell (2) have a projection (13) which extends in the direction of the inner sealing element (7) and / or the outer sealing element (8) and is arranged opposite them.

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