DE29711923U1 - Vibration damping device, in particular vibration damper - Google Patents

Description

G 05564GM / "Vibration absorberZ-damper. ¹¹ / Voitf{Turbo ^# <*mbH*& cS. KC*/ AWrgb«*« /** July 1997

·

Device for damping vibrations of a rotating component,

especially vibration dampers

The invention relates to a device for damping vibrations of a rotating component, in particular a vibration damper, in particular with the features of the preamble of claim 1.

Devices for damping vibrations, in particular vibration absorbers, are known in a wide range of designs. A vibration absorber is understood to be a device that serves to reduce vibrations occurring in the drive train, in particular from rotating components, and not to dampen vibrations during the torque transmission between two components in the drive train. The absorber is therefore not involved in the torque transmission from an input side to an output side.

A main application of such devices is vibration damping in the area of a part of the crankshaft which is opposite the output of the internal combustion engine, ie the coupling with the drive train ^, and which serves to drive auxiliary units - ^e.g. a fan device. Such a system in the form of a

Viscous torsional vibration damper is described in the publication.

This damper comprises a primary mass and a secondary mass, which is referred to as a flywheel. The primary mass is screwed to the free end of the crankshaft and is designed as a closed housing.

The secondary mass, the so-called flywheel, is enclosed as a loose mass inside this housing and is only coupled to the primary mass by the active medium filling the gaps, e.g. in the form of silicone oil. The flywheel is guided radially by a one- or two-part bearing bush. The axial guidance is provided either by the side surfaces of the bush or by an additional ring. The two

G 05564GM / "Vibration absorber/damper." / VoithjTurt)&tin&H& c$. &Kgr;&bgr;7 AWrg'oetdfe / f * July 1997

Parts of the housing are welded, screwed or rolled together. The coupling of the secondary mass with the primary mass through the active medium represents a damping and spring coupling between the housing and the flywheel. This means that the work performed by the thrust forces through a relative movement in the circumferential direction between the primary and secondary masses is not completely converted into heat. The thrust forces also perform a non-negligible loss-free work component in a sinusoidal relative movement of the two damper masses. This type of spring coupling increases the effectiveness of the damping effect and therefore represents a useful effect that must be taken into account when tuning the damper.

The key parameter in tuning the damper is the so-called gap number, which summarizes all dimensions of the effective space that influence the shear stress. By multiplying the gap number by the storage modulus of the silicone oil, you then get the torsional stiffness and by multiplying it by the loss modulus, you get the damping coefficient of the viscous torsional vibration damper. The storage and loss modulus of the silicone oil depend on the excitation frequency of the

20" ^if oil temperature and -depending on the type of oil; ^s - .,--<?&mdash;- _: -,*#.,

The purpose of such a vibration damper is to minimize the torsional stress on rotating components, in particular shafts, e.g. the crankshaft, with the additional condition that the shear stresses of the silicone oil and the heat output in the damper remain within permissible limits. A significant disadvantage of such a system is that optimal coordination by selecting the damping coefficient and the torsional stiffness is not possible, since both functions are taken over by the silicone oil.

G 05564GM / "Vibration absorber/damper." / Voitf{TufoV(3mfc>Hi& Ce. KG*/ AK/rgOC4ee /·7* July 1997

Furthermore, a number of vibration absorbers are known in the prior art which have elastic media as a damping and spring coupling element, for example a rubber spring ring, as disclosed in EP 0 647 796 A1. This vibration absorber comprises an inertia ring which has at least one rubber spring ring and is fixed in a shaft so that it can rotate relatively and which directly touches the outer circumference of the shaft and is pressed against the shaft by the inertia ring so that it cannot rotate. The reactive displacements of the inertia ring which occur during intended use are based exclusively on an elastic deformation of the spring ring within itself. The surfaces which border the spring ring on the inside and outside touch the surfaces which touch them, on the one hand on the shaft and on the other hand on the inertia ring, in a completely immovable manner. The relative displacements of the inertia ring in relation to the shaft that occur when longitudinal and/or torsional vibrations are absorbed exclusively by an elastic deformation of the spring ring. The problem with this design is that an optimal adjustment to the specific application by selecting the appropriate damping coefficient and the stiffness is not possible, since

2Q- * ^To realize both functions the same coupling medium, the elastic ¹ spring ring, is used.

The invention is based on the task of further developing a device for reducing vibrations, in particular a vibration damper, in such a way that the disadvantages mentioned in the prior art are avoided. In particular, an optimal adaptation to the specific application should be achieved by a suitable choice of the damping coefficient and the torsional stiffness. The structural design should be characterized by a small space requirement, simple assembly and, above all, low costs.

G 05564GM / "Vibration absorberZ-damper." / VoitfjTufkJb ^# Qmi?H;& C$. YOI Ali/rgQOjie /·/ July 1997

The solution to the problem according to the invention is characterized by the features of claim 1. Advantageous embodiments are described in the subclaims.

The device for damping vibrations of a rotating component comprises a primary mass that can be coupled to the rotating component at least indirectly in a rotationally fixed manner and a secondary mass in the form of an inertial mass, which can be coupled to one another via a damping and spring coupling. According to the invention, first means for implementing the spring coupling and further second means for implementing the damping coupling are provided. In contrast to the designs known in the prior art, there is therefore a functional division into different devices or means.

In terms of the device, the primary mass can be coupled in a rotationally fixed manner to a rotating component, for example in the form of a shaft, the vibrations of which are to be dampened or reduced. The secondary mass, which is preferably designed in the form of a so-called flywheel ring, is assigned to the primary mass in a loose form and is guided "at least radially" by means of a corresponding bearing. Between the primary mass and the secondary mass, means for transmitting vibrations are provided in the form of at least one compression spring device, preferably arranged and acting in the circumferential direction. Furthermore, between the primary and secondary masses, means for damping longitudinal and/or rotational vibrations are provided, which counteract a relative movement of the primary mass with respect to the secondary mass and convert the work performed by the thrust forces due to the relative movement of the primary mass with respect to the secondary mass, for example into heat. The secondary mass is not connected to other parts of the drive train.

G 05584GM / "Vibration absorber/damper." / Voitt|Tuflft>^#Grr\l>lC&df>. YfHl AK/raQCiSe 1*7 July 1987

connected, so that the entire vibration damping system is not suitable for torque transmission.

The solution according to the invention makes it possible to create a device for damping vibrations, in particular longitudinal and/or torsional vibrations on rotating components, in particular shafts, which enables optimal adaptation to the specific application. In particular, the solution according to the invention makes it possible to control the spring stiffness of the system and the degree of damping independently of one another and much more precisely or finely. The three most important variables for the design of the device for damping vibrations are

1) the moment of inertia I of the secondary mass,

2) the damping and

3) the spring or torsional stiffness

to watch.

Preferably, the damping is hydraulic. For this purpose, the damping means between the primary and secondary masses comprise a

2(T -■ Hydraulic fluid, i.e. an incompressible liquid. The use of other media, e.g. an elastic material, is also conceivable. The damping medium can be arranged in separate, essentially closed chambers, which are provided between the primary mass and the secondary mass with the provision of corresponding, complementary recesses, or in the area of the spring devices. It is conceivable, for example, to provide the damping medium in the area of the device for implementing the angle of rotation limitation. Complete filling or filling of the space between the primary and secondary masses is also possible.

G 05564GM / "Vibration damper." / VoitTwTurfcefimbHS. Ca. KG^*AK/rge018B / 7.»July 1897

The supply of hydraulic fluid as a damping medium can be done once from the outside, during operation or by exchange via a hydraulic fluid supply system. Furthermore, the supply can be done once using a separate

The hydraulic fluid can be supplied by a supply device, i.e. by means of a separate damping filling or directly from the unit to be damped via appropriate supply lines. In this context, it is also conceivable to create a circuit that enables the hydraulic fluid to always be kept at a constant temperature. In this case, it is also possible to use lower-quality hydraulic fluids as a damping medium.

In the structural design, the primary mass, which is preferably designed as a disk-shaped element, can be coupled at least indirectly in a rotationally fixed manner to the rotating component in the drive train, on which longitudinal and/or torsional vibrations occur that are to be compensated. The secondary mass, which is also referred to as the inertial mass, is assigned to the primary mass. For at least radial guidance relative to the element whose longitudinal and/or torsional vibrations are to be dampened.

-■- should be, for the secondary mass a bearing arrangement is required, preferably in, ^

Form of at least one bearing bush, provided by means of which it is supported on the rotating component. Means are provided which ensure rotation of the secondary mass in the form of the inertial mass with the primary mass during the start-up phase and the acceleration phases.

The transmission of the occurring longitudinal and/or torsional vibrations or support on the secondary mass takes place by means of a corresponding device in the form of at least one compression spring unit. The compression spring units are arranged on a certain defined diameter, preferably in the circumferential direction, in corresponding recesses on the primary mass and are supported on the secondary mass. Regarding the structurally conceivable possibilities of the

G 05564GM / "Vibration absorber damper." / VoiltiTu{tip,GmbHt& Ce. KGt/*AK/r90Oiee / 7* July 1997

For the spring support, reference can be made to the statements in the publications DE-OS 36 35 043 and DE 39 16 575. The disclosure content of these publications regarding the possibilities of spring support between two elements is hereby fully included in the disclosure content of the application.

The vibrations caused by relative movements of the primary mass compared to the secondary mass are compensated by the latter via spring devices.

In the optimal case, i.e. when there are no longitudinal and/or torsional vibrations on the drive unit on which the vibration damping device is arranged, the primary and secondary masses rotate at the same speed, i.e. there is no relative movement between the two. The spring devices provided between the two elements only serve to drive the secondary mass during the start-up phase and the acceleration phases. Otherwise, there is essentially no torque transmission.

If longitudinal and/or torsional vibrations occur on the rotating component, they are introduced into the primary mass. The spring devices transfer them to the secondary mass.

Result of the relative movements between the primary and secondary masses.

The secondary mass must be designed in terms of its inertia in such a way that it can support a certain amount of vibration without problems. This design is achieved by setting the moment of inertia I accordingly.

The attenuation of the relative movement that occurs is carried out by appropriate means, preferably hydraulically. In this case, for example, in the area of the compression springs or a stop to limit the angle of rotation, chambers are provided which are filled with a hydraulic fluid.

G 05564GM / "Vibration absorber damper." / VoithiTuiltnGmbH* C«. KG"/ AK^rgO0|$3 / 7'JuIi 1997

can be filled. This fluid is displaced when relative movement occurs between the primary mass and the secondary mass, but represents a resistance.

Furthermore, the use of other elastically deformable materials is conceivable, whereby a large number of arrangement variants between the primary and secondary masses are possible. The damping media can extend over at least part of the radial dimensions of the primary and secondary masses or essentially over the entire dimension. In the simplest case, damping can also be achieved through friction between the two masses - primary mass and secondary mass.

Preferably, devices are provided which limit the relative movement between the primary and secondary masses in the circumferential direction. The limitation is implemented by means of screw connections guided in elongated holes. For this purpose, the primary mass preferably has at least one elongated opening running in the circumferential direction, preferably in the form of an elongated hole, on a certain diameter in the circumferential direction. The secondary mass preferably has at least two parts which form a structural unit - a first part and a second part. The first part essentially characterizes the inertial mass, while the second part serves as a cover plate for sealing the primary mass. The moment of inertia of this second part is preferably relatively low. The first part and second part of the secondary mass enclose the primary mass and are coupled to one another via corresponding connecting elements. The coupling takes place via the primary mass, with the connecting elements being guided through corresponding through-openings on a certain diameter in the circumferential direction of the primary mass. The size of these through-openings on the primary mass in the circumferential direction determines the size of the angle of rotation of the primary mass relative to the secondary mass, due to the longitudinal and/or torsional vibrations introduced.

G 05584GM / "Vibration absorber damper." / VoiKTuaMnGmbHlSi Ce. KG»/*AK/rgBOJ$B / 7· July 1997

Regarding the possibilities, in particular the structural design of the hydraulic damping, reference is made to the publication DE 38 41 692. The disclosure content of the publication regarding the individual possibilities of the damping is hereby included in the disclosure content of this application.

The solution according to the invention makes it possible to provide a structurally simple device for vibration damping of a rotating component for different purposes, whereby an optimal design can be achieved in adaptation to the specific application by suitable selection of the corresponding moment of inertia I of the secondary mass, the spring stiffness, the means for compensating the vibrations and the damping. Due to the simplicity of the structure, this variant is also characterized by low costs.

The overall system offers the advantage of realizing an optimal adaptation of the vibration damper to the specific application, since the individual influencing factors can be changed and determined independently of one another through structural design with the smallest possible number of components, which means that the effort required and the costs of the -. - ---r■-■■■· overall system are kept relatively low.

The solution according to the invention is explained below using figures. The following is shown in detail: 25

Fig.1 shows an embodiment of a device according to the invention for vibration damping of a rotating component in axial section;

Fig.2 shows a view I -1 corresponding to Fig.1. 30

G 05564GM / "Vibration absorber damper." / VoitTiJrurfcg ßmbHji C<i. KG^K/rgCOI« / 7.·July 1997

Figure 1 shows an axial section of a design of a device for vibration damping 1 of a rotating component, in particular a vibration damper, which is used to dampen longitudinal and/or rotational vibrations on a rotating component, for example a shaft 2. The damper 1 comprises two masses, a first so-called primary mass 3 and a second so-called secondary mass 4. The secondary mass 4 is also referred to as an inertial mass or flywheel. The primary mass 1 can be coupled in a rotationally fixed manner to the rotating component whose vibrations are to be dampened, i.e. the shaft 2.

In the case shown, the primary mass 3 is connected to the shaft 2 in a rotationally fixed manner. In the simplest case, the primary mass 3 is designed as a disk-shaped element which has recesses 5, preferably in the form of through-openings, in the circumferential direction on a certain diameter d _1. In the simplest case, the secondary mass 4 comprises a first part in the form of a flywheel ring 6. In the case shown,

In the embodiment, a second part 7 is additionally provided, which is coupled to the flywheel 6 in a rotationally fixed manner. The connection between the first part 6 and the second part 7 is made via connecting elements 8, which are preferably designed in the form of screw connections. The -20- - radial guidance of the secondary mass 4* is carried out via a bearing arrangement 9;..-*~* The bearing arrangement 9 comprises a bearing bush 10, which is arranged between the shaft 2 and the secondary mass 4 in the radial direction. The bearing is designed as a plain bearing and is supplied with lubricant via a lubricant connection 11. In the case shown, the lubricant is supplied via the shaft 2.

The secondary mass 4 is loosely arranged or mounted opposite the primary mass 3. A coupling between the two masses is realized to realize the spring coupling via at least one spring device 12, which comprises at least one compression spring device. The spring device 12 is for this purpose in the recesses 5 in the primary mass

G 05564GM / "Vibration absorber damper." / Voi&iTul«rf3mbHii!i Ce. KGV*AK/rg!)0ia3 / 7· July 1997

arranged, extends in the circumferential direction of the primary mass 3 and is supported on the secondary mass 4. The function of the spring device 12 is to transfer torque to the secondary mass during the start-up and/or acceleration phases in order to set it in rotation. During operation, i.e. when the shaft 2 rotates in the optimal case in which no vibrations occur, both - primary mass 3 and secondary mass 4 - rotate at the same speed. In this case, no torque is transferred to the secondary mass or only to a small extent. The latter is simply carried along.

With regard to the implementation of the support of the spring devices between the primary and secondary masses, reference can be made to the embodiments according to DE 36 35 043 and DE 39 16 575, the disclosure content of which is included in this application. For example, it is conceivable that in the present case both parts 6 and 7 of the secondary mass have window-shaped cutouts running in the circumferential direction on a certain diameter d ₂ , which are designed in a way that is essentially complementary to the recesses on the primary mass that accommodate the spring devices 12 in terms of their distance from one another and their size. Both parts grip the spring devices 12 tangentially on both sides or, as shown in Figure 2, on the guide pieces 20 assigned to their ends. Furthermore, this also applies to the recess 5 on the primary mass.

If longitudinal and/or torsional vibrations occur on the shaft, these are introduced into the primary mass 3 via the rotationally fixed coupling of the primary mass 3 with the shaft. Under the effect of a torsional moment during the operation of the rotating component, the spring devices 12 are compressed and thus there is a relative movement between the primary and secondary masses, which leads to the setting of a certain angle of rotation alpha, whereby the vibrations are compensated by the secondary mass 4.

G 05564GM / "Vibration absorberZ-damper."

C«. KGV AK/rgCOiae / 7.·July 1997 &bull; · · ··· ·

Appropriate means are provided for damping the relative movement between the primary mass 3 and the secondary mass 4. In the case shown, the damping is carried out using a hydraulic fluid. This is filled into a space between the primary mass 3 and the secondary mass 4, which is designated here by 13. The filling of the space can be carried out in such a way that either only the area in which the spring devices 12 are located or additional chambers, not shown in detail here, which can be formed between the primary and secondary masses, are filled or the entire space between the primary mass 3 and the secondary mass 4. In the case shown, it is possible to form the damping chamber 22 between the bushing 21 surrounding the connecting element 8 and the elongated hole 16. There are a number of different options for filling with hydraulic fluid. In the case shown, the supply of hydraulic fluid is carried out via a corresponding

Hydraulic fluid supply device 14 via the shaft 2. The filling of the gap 13 can be done once or, depending on the application, via the rotating units. Theoretically, it is also possible to design the supply or supply of hydraulic fluid in the gap in such a way that the hydraulic fluid present in the gap can also be exchanged when heated. For this purpose, appropriate discharge lines must be provided. The case shown illustrates the possibility of supplying the gap 13 with hydraulic fluid via the hydraulic fluid supply system 14. Part of this hydraulic fluid supply system is the operating medium or lubricant system of the shaft 2, which is coupled to the gap 13 via a connecting line 15. The bearing arrangement 10 is also supplied with lubricant from the same operating medium or lubricant supply system.

G 05564GM / "Vibration absorberZ-damper." / VoifhJTuiJsf .GmbHji CJ. KG^*AK/rgt)01$3 / 7.July 1997

Another option, not shown here, is to fill the chambers with grease.

The angle of rotation σ in the circumferential direction of the primary mass 3 relative to the secondary mass 4, which causes the spring device 12, which preferably comprises at least one compression spring, to be compressed, can be limited in accordance with the embodiment in Figure 1. The limitation is achieved by means of corresponding stops on the primary mass 3. These stops are implemented via elongated holes 16 in the primary mass 3, which are arranged on a specific diameter in the circumferential direction and are preferably distributed at equal distances from one another in the circumferential direction. For this purpose, projections in the region of the diameter d ₂ are assigned to the secondary mass 4, which, in the installed position, protrude into the recesses or the elongated holes of the primary mass 3. The projections are designed in such a way that the elongated holes can be moved in the circumferential direction relative to the projections without any problems. It is also conceivable to assign the function of the projection-bearing element to the primary mass and to provide the recesses on the secondary part or the secondary mass.

Friction between the two, i.e. the projections of the secondary mass and the primary mass, must be avoided. The projections can be part of the secondary mass 4, i.e. form a structural unit with it, or can be implemented using additional elements. In the case shown, the connecting elements 8, which connect the first part 6 of the secondary mass 4 to the second part 7 in a rotationally fixed manner, take over the function of these projections. The connecting element 8 extends through the slot 16 of the primary mass 3. This coupling and assignment to the primary mass 3, i.e. in the case shown, enclosing the primary mass 3 in the axial and radial direction and corresponding design of the bearing of the secondary mass 4, and additional elements

G 05564GM / "Vibration absorberZ-damper." / Voi1t>jriji|iopmbH$i C(J KG^*K/rg$01$ / 7,AIi 1997

the secondary mass 4 is fixed in the axial direction. The elongated hole or elongated holes 16, which extend in the circumferential direction on the primary mass 3, then form the stop for the connecting element 8, which limits the possible angle of rotation α when the primary mass 3 moves relative to the secondary mass 4. The angle of rotation α is limited by the extension I of the elongated holes 16 in the circumferential direction. The use of connecting elements to implement this stop or limiting function for the angle of rotation σ makes it possible to create a compact system with simple, easily replaceable components. If the secondary mass 4 is designed with projections that form a structural unit with the secondary mass 4, additional measures would be required to fix the secondary mass 4 axially.

Figure 2 shows a view of the primary mass I-1 corresponding to Figure I. This shows the elongated holes 16. The extension of the elongated holes in the circumferential direction _I1, the connecting element 8 and the recesses for the spring devices 12, which are only indicated here, the recesses being designated here with 5. The same recesses are also located in the areas of the secondary mass 4 which are adjacent in the installed position. These are designated there with 17 or for the second part of the secondary mass 4.

Claims (9)

G 05564GM / "Vibration absorber" / VoifhJ'urteßmbHi C* KGV*AK/rgtoi& / 7.JuIi 19&THgr;7 P-atei^anspnjche 1. Device for damping vibrations of a rotating component, in particular a damper 1.1 with a primary mass that can be coupled at least indirectly in a rotationally fixed manner to the rotating component; 1.2 with a secondary mass; 1.3 the primary mass and the secondary mass can be coupled to one another via a damping and spring coupling; characterised by the following features: 1.4 with first means for realizing the spring coupling and further second means for realizing the damping coupling. 2. Device for vibration damping according to claim 1, characterized in that the first means comprises at least one compression spring acting in the circumferential direction between the primary mass and the secondary mass. 3. Vibration damping device according to claim 2, characterized by the following features: .^ - ■«■■--- ·..·.·* ■.* 3.1 the primary mass comprises first recesses running along the circumference; 3.2 the secondary mass comprises, in the installed position, second recesses which are essentially complementary to the first recesses on the primary mass in terms of their spacing and size; 3.3 Each spring device is assigned a guide body at each spring end, to which the two masses - primary mass and secondary mass - act tangentially in the area of the recesses. G 05564GM / "Vibration absorberZ-damper." / Voit^Tu8W3mbHi& Ce. KG/AK/rgboiJe / 7 July 1997 4. Device for vibration damping according to one of claims 1 to 3, characterized in that the stiffness of the spring coupling is determined by the number and/or design of the individual compression spring devices. 5. Vibration damping device according to one of claims 1 to 4, characterized in that the second means comprises at least one elastic element which is arranged between the primary mass and the secondary mass. 6. Device for vibration damping according to one of claims 1 to 4, characterized by the following features: 6.1 the second means comprises at least one
hydraulic fluid supply system; 6.2 the hydraulic fluid supply system is coupled with a gap between the primary mass and the secondary mass. 7. Device for vibration damping according to one of claims 1 to 6, characterized in that further third means for Limitation of the twist angle of the primary mass relative to the Secondary mass is provided in the circumferential direction. 8. Device for vibration damping according to claim 7, characterized by the following features: 8.1 the third means comprises at least one projection arranged on the secondary mass; 8.2 the projection engages in recesses on the primary mass in the installation position in the circumferential direction in such a way that it can be displaced relative to the primary mass; 8.3 the recesses on the primary mass in the circumferential direction form a stop for the projection of the secondary mass. G 05564GM / "Vibration absorber damper." / VoitH;TuJ35.GmbHjl C{. KGjVK/rg})01$3 I 7.JuIi 1997 17 9. Device for vibration damping according to claim 8, characterized in that the projection is realized via a connecting element in the form of a screw.