Viscosity-torsional vibration damper or absorber for a crankshaft of a combustion engine

Abstract

A viscosity-torsional vibration damper or absorber for a crankshaft of a combustion engine includes an annular damping or absorbing arrangement which can be fastened to the crankshaft. The damping or absorbing arrangement is fastened in an outer diameter region to a holding device which, on the other hand, can be fastened to the crankshaft and can be sprung in the axial direction of the crankshaft, but is inherently rigid radially with respect to the crankshaft.

Claims

1. A viscosity-torsional vibration damper or absorber for a crankshaft of an internal combustion engine, comprising: a ring-shaped damping or absorption arrangement which is fastenable on the crankshaft, wherein the damping or absorption arrangement is arranged in an outer diameter region on a holding apparatus, which on the other hand is arrangeable, on the crankshaft and which is formed to be capable of being sprung in an axial direction of the crankshaft, but inherently rigid radially with respect to the crankshaft, the damping or absorption arrangement has a ring-shaped housing which is fastenable on the crankshaft with a flywheel which is mounted rotatably therein in a silicon oil relative to the housing, the ring-shaped housing is fastened in an outer diameter region on an end surface or on both end surfaces on two of the holding apparatuses which project in the direction of the crankshaft beyond the housing, and the two holding apparatuses are fastened on two opposite end surfaces of the ring-shaped housing and protrude in the direction of the crankshaft beyond the ring-shaped housing, and in said protruding region are connected to one another by a spacer sleeve, wherein the two holding apparatus are configured to be inherently rigid radially relative to the crankshaft and configured to be capable of being sprung in the axial direction of the crankshaft, and overall the arrangement with the two holding elements is fixable on the crankshaft.

2. The viscosity-torsional vibration damper or absorber as claimed in claim 1, wherein the holding apparatuses are formed from an annular connecting disk.

3. The viscosity-torsional vibration damper or absorber as claimed in claim 1, wherein the holding apparatuses is or are composed in each case from several sector-shaped struts.

4. The viscosity-torsional vibration damper or absorber as claimed in claim 3, wherein the connecting discs or the struts are provided with axial openings.

5. The viscosity-torsional vibration damper or absorber as claimed in claim 4, wherein the openings are formed to be circular, arc-shaped and/or sector-shaped.

6. The viscosity-torsional vibration damper or absorber as claimed in claim 1, wherein a damping element, which acts in the axial direction, is arranged between the spacer sleeve and the housing.

7. The viscosity-torsional vibration damper or absorber as claimed in claim 6, wherein the damping element is composed of a ring which is supported at the end side on both holding apparatuses.

8. The viscosity-torsional vibration damper or absorber as claimed in claim 7, wherein the ring is produced from an elastomer.

9. A crankshaft, comprising a viscosity-torsional vibration damper according to claim 1, the damper or absorber being arranged on the crankshaft.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a partial section through a viscosity-torsional vibration damper according to the invention.

(2) FIG. 2 shows a schematically represented view in the direction of arrow II in FIG. 1 with alternative configurations of a holding apparatus for a housing of the viscosity-torsional vibration damper from FIG. 1.

(3) FIG. 3 shows a further exemplary embodiment for a holding apparatus of a housing of a viscosity-torsional vibration damper.

(4) FIG. 4 shows a further holding apparatus for a housing of a torsional vibration damper.

(5) FIG. 5 shows a partial section corresponding to FIG. 1 through a further exemplary embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

(6) In FIG. 1, the reference number 1 designates overall a viscosity-torsional vibration damper which can be fixed on a flange 2 of a crankshaft 3 of an internal combustion engine. The following statements can be applied in an analogous manner to viscosity-torsional vibration absorbers.

(7) Viscosity-torsional vibration damper 1 of FIG. 1 comprises, as a ring-like damping or absorbing arrangement in a preferred configuration, a ring-like housing 4 with a flywheel 5 mounted rotatably therein in a viscous medium such as a silicon oil or the like.

(8) Here, it further comprises two holding apparatuses 6 which are fastened on the one hand on opposite end surfaces of housing 4 and on the other hand on a spacer sleeve 7, wherein both holding apparatuses 6 can be fixed jointly with spacer sleeve 7 on flange 2 of a crankshaft 3. The connection of holding apparatuses 6 to housing 4 is performed in the outer diameter region of housing 4. Here, holding apparatuses 6 can further in a preferred configuration be held in each case via spacers or spacer rings 8 at a distance to the end surfaces of housing 4.

(9) Holding apparatuses 6 are configured in such a manner that these holding apparatuses are formed to be inherently rigid radially with respect to crankshaft 3 and are configured to be capable of being sprung in the axial direction of crankshaft 3.

(10) As FIG. 1 clearly shows, holding apparatuses 6 project in the direction of crankshaft 3 beyond housing 4 and are fastened in this region with spacer sleeve 7 and flange 2 of crankshaft 3.

(11) Due to the fact that holding apparatuses 6 are formed to be capable of being axially sprung, it is possible to effectively damp or absorb axial vibrations of crankshaft 3 which occur during operation.

(12) Since holding apparatuses 6 are in contrast formed to be inherently rigid in the direction running radially with respect to crankshaft 3, the action of viscosity-torsional vibration damper or absorber 1 in the circumferential direction is not impaired.

(13) The exemplary embodiment of the invention represented in FIG. 1 with two holding apparatuses 6 on both end sides of housing 4 has the advantage that housing 4 can where necessary also act as a belt pulley since the bending moment introduced by the belt can be taken up by both holding apparatuses 6 without deformation.

(14) If, however, the use of viscosity-torsional vibration damper or absorber 1 without the use of a belt is intended, a single holding apparatus 6 on an axial end side of housing 4 is also sufficient.

(15) Holding apparatuses 6 can advantageously be formed from annular connecting disks. These annular connecting discs can, as FIG. 2 very clearly shows, be broken through with openings 9 of various graphic configurations in order to set a desired capability to be sprung axially with respect to crankshaft 3.

(16) It is thus possible to attach circular, sector-shaped or sickle-shaped openings 9 in order to achieve a desired capacity to be axially sprung of holding apparatuses 6.

(17) As FIGS. 3 and 4 make clear, holding apparatuses 6 can, however, also be formed from several sector-shaped struts 10 which are fastened at their outer ends on a ring 11 and in the central region on a sleeve 12, as a result of which a fully manufacturable mounting unit is formed. It is, however, also conceivable, as FIG. 3 shows, that sector-like struts 10 are fixed in their outer edge region directly with housing 4 and centrally on a spacer sleeve 7 as in the case of the exemplary embodiment according to FIG. 1.

(18) The exemplary embodiment of the invention represented in FIG. 5 shows that a damping element which acts in particular in the axial direction and can have, for example, the form of a ring 13 is arranged between housing 4 and spacer sleeve 7, wherein this damping element reaches at the end sides to both holding apparatuses 6. As a result of this vibration-isolated fastening of the damper on crankshaft 3, the axial resonant frequencies of the crankshaft-damper system are increased (up to the frequency of the vibration isolation). This can be advantageous since as a result of this the resonant frequencies are simultaneously increased and in the most expedient case these resonances then lie outside the excitation spectrum.

(19) As a result of the additional damping shown here between damper housing 4 and crankshaft flange 2, in the case of which ring 13 is composed, for example, from an elastomer, not only is the vibration isolation damped, but also all the axial resonant frequencies, as a result of which viscosity-torsional vibration damper 1 then takes on the additional function of a seismic axial vibration damper. The adjustment of the torsional vibration damping function is entirely independent of the function axial vibration damping in this case.

LIST OF REFERENCE NUMBERS

(20) 1 Viscosity-torsional vibration damper 2 Flange 3 Crankshaft 4 Housing 5 Flywheel 6 Holding apparatus 7 Spacer sleeve 8 Spacer ring 9 Opening 10 Strut 11 Ring 12 Sleeve 13 Ring