WO2015124150A1

WO2015124150A1 - Sealing lip for a sealing element for sealing two parts that can move in relation to one another

Info

Publication number: WO2015124150A1
Application number: PCT/DE2015/200021
Authority: WO
Inventors: Jérémy Keller
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2014-02-24
Filing date: 2015-01-23
Publication date: 2015-08-27
Also published as: DE112015000935A5

Abstract

The invention relates to a sealing lip (1) for a sealing element (2) for sealing two parts (10, 11) that can move in relation to one another, said sealing lip comprising at least the following components: a contact lip (3) having a length (4) designed to moveably and entirely abut a corresponding sealing surface (5) in the assembly, thereby generating a sealing effect; a spring arm (6) that exerts, in the assembly, a preload force on the contact lip (3), such that the contact lip (3) is pressed onto the corresponding sealing surface (5), said sealing lip (1) having at least one mass element (7, 8) that increases the mass of the sealing lip (1).

Description

Sealing lip for a sealing element for sealing two relatively movable

parts

The invention relates to a sealing lip for a sealing element for sealing two relatively displaceable parts and a sealing element and a hydraulic or pneumatic return system for a friction clutch, in particular for a motor vehicle.

Various sealing elements are known from the prior art, which are suitable for sealing in a hydraulic system. In this case, however, due to the spring force of the sealing lip and the frictional contact with the corresponding sealing surface, a so-called stick-slip effect occur, that is, the sealing lip lifts due to the friction and the bias and lowers again, thus generating an audible noise, for example a rattle or squeak.

On this basis, the present invention has the object, at least partially overcome the known from the prior art disadvantages. The object is solved by the features of the independent claims. Advantageous developments are the subject of the dependent claims.

The invention relates to a sealing lip for a sealing element for sealing two relatively displaceable parts, which comprises at least the following components: a contact lip with a circumference, which is adapted to abut circumferentially slidably in installation on a corresponding sealing surface and thus set a sealing effect;

a spring arm, which exerts a biasing force on the contact lip during installation, so that the contact lip is pressed against the corresponding sealing surface,

characterized in that

the sealing lip further comprises at least one mass element which increases the mass of the sealing lip.

The sealing lip is provided for example for a sealing element of a piston, for example a master piston or slave piston of a hydraulic or pneumatic return system, and serves to seal a hydraulic fluid or a

pneumatic gas relative to the environment. For this purpose, the sealing lip has a contact lip which rests on a corresponding sealing surface and carries out a movement relative to the sealing surface. The contact lip is so by means of a spring arm against the Pressed sealing surface that no or only a negligible amount of hydraulic fluid or pneumatic gas can break this barrier.

The spring arm not only has to apply the force to the contact lip, but it can also be set up so that it is supported by the fluid and the contact lip is additionally pressed against the corresponding sealing surface. The sealing lip proposed here also has a mass element, which increases the mass of the sealing lip. By increasing the mass of the sealing lip, the inertia of the sealing lip is increased and thus reduces the likelihood of lifting the contact lip of the corresponding sealing surface. In addition, the natural frequency of the sealing lip is changed, so that the necessary excitation frequency for a Sti ck-S I i p effect e ect is changed. This at least reduces the noise.

According to a further advantageous embodiment of the sealing lip is at least one

Ground element arranged at the extreme end of the spring arm.

The arrangement of the mass element at the end of the spring arm, the mass is increased at the end of the spring arm and thus the ratio between spring and mass, which are the relevant components for a vibration, ideally exploited, at the same time the contact lip almost unchanged at the corresponding sealing surface can be present. In this case, it must be ensured that the mass elements come into contact with the sealing surface in as little as possible, because they could thus change the vibration behavior of the sealing lip or even impair the sealing effect of the sealing lip.

In a further advantageous embodiment of the sealing lip, a plurality of mass elements are arranged spaced from each other over the circumference of the contact lip.

The mass is further increased by the plurality of mass elements. Furthermore, a new element is generated, which taken together for an increase in the mass of

Sealing lip ensures. In addition, no vibration of a single mass element can be transmitted directly to an adjacent mass element, but only indirectly attenuated by the over the contact lip or the spring arm, which usually consists of a

Elastomer are made. Due to the arrangement on the circumference of the contact lip can

In particular, with the above-described feature of the arrangement of the mass elements at the outer end of the spring arm an increase in the total mass of the sealing lip can be achieved at a particularly effective location with respect to the spring arm. According to a further advantageous embodiment of the sealing lip, a plurality of mass elements is provided, wherein the mass elements differ at least partially by their mass, wherein preferably the mass elements are not arranged symmetrically with the same mass.

In this advantageous embodiment, at least some differ

Mass elements of others, particularly preferably two types of mass elements or several types of mass elements are provided. Due to the different masses of the mass elements, a different excitation of the mass elements is achieved.

This results in no uniform but an irregular loading of the contact lip or the spring arm and thus to an irregular relief of the corresponding sealing surface with a corresponding excitation of the sealing elements. As a result, the noise is significantly reduced and greatly improves the sealing effect. Most preferably, the mass elements are arranged so that the damping effect of the sealing lip to extinguish suggestions of others

Mass elements leads. In this case, the deformation is preferably in the contact lip

or added to the Federaurm that it regularly comes to internal friction and heating and thus the excitation is converted into heat energy, rather than moving

According to a further aspect of the invention, a sealing element for sealing two relatively displaceable parts is proposed, wherein the sealing element is a

A receptacle for a first part and a sealing lip according to one of the preceding claims, and wherein the contact lip for abutment against a relative to the first part

movable second part is set up.

The sealing element has a receptacle for a first part, for example a piston, wherein the sealing lip is arranged with its contact lip for abutment against a second part, for example the cylinder wall of a cylinder. The first part and the second part are movable relative to each other, in absolute terms, the sealing element can be moved or the corresponding sealing surface of the second part relative to the sealing lip can be moved. The contact lip is prevented due to the at least one mass element in many states of excitement from performing a stick-slip effect and thus to produce a lower noise. According to a further aspect of the invention, a hydraulic or pneumatic return system for a friction clutch is proposed which comprises at least the following

Components comprising:

a master piston in a master cylinder,

a slave piston in a slave cylinder, wherein the master cylinder and the slave cylinder fluidly communicate with each other, so that a movement of the master piston is convertible into a movement of the slave piston, wherein at least one of the piston comprises at least one sealing element according to the above description, wherein by means of the sealing element of the piston opposite the associated cylinder can be sealed in such a way that an overflow of the fluid in the associated cylinder can be prevented.

The hydraulic or pneumatic return system consists of a master piston, which can compress a master cylinder in a master cylinder and a corresponding slave piston, which in a slave cylinder due to a volume expansion in

Slave cylinder is moved. Contrary to the naming of master piston and slave piston and a retrograde transmission of forces is possible. In addition, a translation can take place by different piston surfaces or other elements. At least one of the pistons in this case has a sealing element according to the above description, wherein the

Sealing element due to the at least one mass element only a reduced stick-slip effect exerts. Due to friction in the sealing element, it is particularly preferred that a piece effect be prevented so far that noise development no longer takes place and a significantly improved sealing effect is achieved over all excitation states.

According to another aspect of the invention is a friction clutch with a

Rotary axis for releasably connecting an output shaft proposed with a drive train, which has at least the following components:

at least one friction pack, wherein a torque can be transmitted via the friction pack in the pressed-on state;

a return system according to the above description for actuating the Reibpakets means of the slave piston.

The friction clutch is adapted to releasably transfer torque from an output shaft to a drive train and vice versa. This is generally achieved via the at least one friction pack, as described above, which has an axially displaceable pressure plate which is rotationally fixed, as a rule, with the output shaft, which can be pressed against at least one corresponding friction disk and then a torque can transfer. The force is generated by an actuating system which is actuated directly or indirectly by a user. From this actuation system, the force goes out, which leads to an axial compression of the at least one Reibpakets. Particularly preferably, the actuating system is arranged hydraulically or pneumatically, whereby particularly large axial forces can be generated and a transmission ratio is easily adjustable. Here, the use of a sealing element according to the above

Description advantageous because noise can disturb the driver. In particular, noises of novel elements such as a hydraulic or pneumatic

Translation, where conventionally a lever mechanism was used.

According to a further aspect of the invention, a motor vehicle is proposed, which has a drive unit with an output shaft, a drive train and a

Has friction clutch according to the above description for releasably connecting the output shaft to the drive train.

Most motor vehicles today have a front-wheel drive and therefore preferably arrange the drive unit, for example an internal combustion engine or an electric motor, in front of the driver's cab and transversely to the main drive direction. The space is particularly small in such an arrangement and it is therefore particularly advantageous to use a friction clutch small size.

The installation space situation for passenger cars of the small car class according to European classification is exacerbated. The units used in a passenger car of the small car class are not significantly reduced compared to passenger cars larger car classes. Nevertheless, the available space for small cars is much smaller. The sealing lip proposed here allows noise-free operation of a hydraulic release device. This is particularly pleasant for the driver and for small cars, the hydraulic actuation prevails due to increasing component quantities.

Passenger cars are classified according to a vehicle class according to, for example, size, price, weight, power, this definition being a constant change according to the

Market needs. In the US market, vehicles of the class small cars and microcars are classified according to European classification of the class of Subcompact Car and in the British market they correspond to the class Supermini, for example, the class City Car. Examples of the Kleinstwagenklasse are a Volkswagen Fox or a Renault Twingo. Examples of the small car class are an Alfa Romeo Mito, Volkswagen Polo, Ford Fiesta or Renault Clio.

The features listed individually in the claims can be combined with each other in any technologically meaningful manner and can be supplemented by explanatory facts from the description and details of the figures, with further

Embodiments of the invention will be shown.

The invention and the technical environment will be explained in more detail with reference to FIGS. The figures show particularly preferred embodiments, to which the invention is not limited. In particular, it should be noted that the figures and in particular the illustrated proportions are only schematic. Show it:

1: a sealing element with sealing lip,

2: a sealing lip with a plurality of mass elements, FIG. 3: a sealing element with a plurality of different mass elements, FIG. 4: a hydraulic or pneumatic reverse system with friction clutch, FIG. 5: a motor vehicle with friction clutch.

In Fig. 1, a sealing element 2 is shown with a sealing lip 1, which receives a first part 10 and by means of the contact lip 3 of the sealing lip 1 with a second part 1 1 in contact, wherein the first part 10 and the second part 1 1 relative are mutually displaceable. The sealing lip 1 has a spring arm 6 and a contact lip 3, wherein the contact lip 3 is mounted in the vicinity of the outermost end 9 and the spring arm 6 exerts a biasing force on the contact lip 3. At the outermost end 9 viewed from the connection of the spring arm 6 of the sealing lip 1 on the sealing element 2, a first mass element 7 is arranged. As a result, the mass spring system of the sealing lip 2 is changed in favor of a higher inertia and lower excitation frequency. The mass element 7 comes at no time with the corresponding sealing surface 5 in contact.

FIG. 2 shows a plan view of a sealing lip 1, wherein a plurality of identical first mass elements 7 are arranged on the circumference 4 of the sealing lip 1.

In Fig. 3 is a similar arrangement as shown in Fig. 2, wherein here a first

Mass element 7 several times in alternation with a second mass element 8 on the Scope 4 of the sealing lip 1 are distributed, wherein the mass of the two mass elements 7 and 8 differs. Thus, an uneven excitation of the sealing lip 1 is achieved, whereby a Walgbewegung is generated, which is converted into heat and thus an input excitation energy is converted into heat and an excitation-induced stick-slip effect is avoided.

In Fig. 4, a hydraulic or pneumatic return system 12 is shown, wherein a

Master piston 14 in a master cylinder 15 via a clutch pedal 28 can be actuated. The master piston 14 is sealed relative to the master cylinder 15 by means of a sealing element 2, as shown for example in FIG. 1, and thus a fluid 18 in the master cylinder 15 can be influenced by the master piston 14. Via the connecting line 30, the fluid is pressed into the slave cylinder 17 when the clutch pedal 28 is actuated, and the effect of the flowing fluid 18 is transmitted to the slave piston 16 by means of a further sealing element 2, as shown, for example, in FIG. This in turn actuates a plate spring 31, which thus releases the friction pack 22 of a friction clutch 13, so that a torque applied to an output shaft 20 is released from a transmission to the transmission shaft 29. The friction clutch 13 has an axis of rotation 19 about which the elements of the friction clutch 13 are rotatable.

In Fig. 5, a motor vehicle 23 is shown with a drive unit 24, which is arranged with its motor axis 27 transversely to the longitudinal axis 26 in front of the driver's cab 25. The

Drive unit 24 is shown here as an internal combustion engine, which has an output shaft 20 by means of a friction clutch 13, a rotation axis 19 in alignment with the motor axis 27, connected to a drive train 21 shown here purely schematically.

With the sealing lip proposed here with at least one additional mass element, the stick-slip effect is reduced and the mass inertia of the lip is increased, without the rigidity of the sealing lip being changed. Sealing lip

sealing element

contact lip

scope

sealing surface

spring arm

first mass element

second mass element

extreme end

first part

second part

hydraulic or pneumatic reverse system friction clutch

master piston

Master cylinder

slave piston

slave cylinder

fluid

axis of rotation

output shaft

powertrain

Reibpaket

motor vehicle

drive unit

cab

longitudinal axis

motor axis

clutch pedal gear shaft

connecting line

Belleville spring

Claims

claims

1 . Sealing lip (1) for a sealing element (2) for sealing two relative to each other

sliding parts (10.1 1), comprising at least the following components:

- A contact lip (3) with a circumference (4) which is adapted to slidably abut in installation on a corresponding sealing surface (5) and thus set a sealing effect;

- A spring arm (6) which exerts a biasing force on the contact lip (3) during installation, so that the contact lip (3) is pressed against the corresponding sealing surface (5), characterized in that

the sealing lip (1) further comprises at least one mass element (7, 8) which increases the mass of the sealing lip (1).

Second sealing lip (1) according to claim 1, wherein at least one mass element (7,8) at the outermost end (9) of the spring arm (6) is arranged.

3. Sealing lip (1) according to claim 1 or 2, wherein a plurality of mass elements (7,8) over the circumference (4) of the contact lip (3) are arranged spaced.

4. Sealing lip (1) according to one of the preceding claims, wherein a plurality of

Mass elements (7,8) is provided and wherein the mass elements (7,8) differ at least partially by their mass, wherein preferably the mass elements (7,8) are not arranged symmetrically with the same mass.

5. sealing element (2) for sealing two relatively displaceable parts (10, 1 1), wherein the sealing element (2) comprises a receptacle for a first part (10) and a sealing lip (1) according to one of the preceding claims and wherein the Contact lip (3) is arranged to rest on a first part (10) relatively displaceable second part (1 1).

6. Hydraulic or pneumatic return system (12) for a friction clutch (13),

comprising at least the following components:

a master piston (14) in a master cylinder (15), a slave piston (16) in a slave cylinder (17),

wherein the master cylinder (15) and the slave cylinder (17) fluidly communicate with each other, so that a movement of the master piston (14) in a movement of the slave piston (16) is implementable, wherein at least one of

Piston (14,16) comprises at least one sealing element (2) according to claim 5, wherein by means of the sealing element (2) of the piston (14) relative to the associated cylinder (15) is sealable such that an overflow of the fluid (18) in the associated Cylinder (15) can be prevented.

7. friction clutch (13) having an axis of rotation (19) for releasably connecting a

Output shaft (20) with a drive train (21), comprising at least the following components:

- At least one friction pack (22), wherein on the friction pack (22) in the pressed state, a torque is transferable;

- A return system (12) according to claim 6 for actuating the Reibpakets (22) by means of the slave piston (16).

8. Motor vehicle (23) comprising a drive unit (24) with an output shaft (20), a drive train (21) and a friction clutch (13) according to claim 7.