DE4205493C1 - Crankshaft bearing with axial damping for IC engine - has non elastic shells between bearing shells and housing to accommodate axial movements - Google Patents

Abstract

The crankshaft (3) of the IC engine is mounted inside the housing (1) via a bearing block (5) split in a plane through the centre of the shaft. Two bearing shells (9,10) support the crankshaft and the bearings are supported inside the bearing block by two outer shells (14,15,17,18) arranged in half shells. The outer shells are non elastic and accommodate small axial movements. The bearing shells support the crankshaft via a lubrication gap (11) while the support shells only have axial movement. The support shells are mounted via lateral flanges (19,20) parallel to the join line in the bearing block. USE/ADVANTAGE - IC engine crankshaft bearing with axial damping giving large reduction in axial vibrations between crankshaft and housing, quieter running engine.

Description

The invention relates to a bearing for a crankshaft Internal combustion engine according to the preamble of claim ches 1 specified characteristics.

A crankshaft bearing with a vibration-damping insert is known from DE-PS 33 09 792. The Lagerscha le on an elastic insert body, which from the combustible engine noise on the piston excited and on the crankshaft vibrations transmitted to the crankcase in radial Dampens direction. The generated by the combustion noise Axial vibrations of the crankshaft, which are also used for excitation of the crankcase and thus for the emission of airborne sound contribute, however, from the cushioning effect of the insert body hardly detected. In addition, as a result of the motor Combustion on the piston forces the crankshaft bent, which reduces the lubrication gap and thus the excitation of the crankcase by the axial vibrations of the Crankshaft is even further reinforced.

From DE-OS 38 13 223 is a bearing for a reciprocating machine ne known, in which a between the bearing shells and bearing housing Structure-borne noise reducing insert made of an inelastic rule material, especially ceramic is provided.

The invention has for its object a generic Develop crankshaft bearings in such a way that a possible good damping of the vibration excitation of the crankcase infol ge of the axial vibration generated by the combustion noises conditions of the crankshaft is achieved.  

The object is according to the invention in that in claim 1 specified characteristic features solved.

An insert body is made of an inelastic material provided which moves in the longitudinal direction of the crankshaft arranged bar between the bearing shell and the bearing housing is. This will transfer part of the crankcase NEN excitation energy of the axial vibrations of the crankshaft in a sliding movement of the insert body in the longitudinal direction of the cure belwelle implemented. Overall, this reduces the suggestions energy on the crankcase, which provides good damping of the Combustion noise from the engine is reached.

In an advantageous embodiment of the invention according to An Proverb 2 is through the complete enclosure of the camp peel the excitation energy of the vibrating body from the insert body The crankshaft is extensively absorbed by this, which means a large greater proportion of excitation energy in a sliding movement of the one position body implemented and thus a particularly good damping is achieved.

In a further advantageous embodiment of the invention according to claim 3, the bearing shell of insert bodies Mehrla gig enclosed. Due to the additional layers on insert bodies the damping of the axial vibration transmission continues elevated. An inner insert body transmits the through its sliding motion already damped vibration excitation on egg NEN outer insert body, which in turn the vibration excitation due to its sliding movement in the longitudinal direction of the crank wave dampens.

The insert body is made as smooth as possible their friction on the bearing bracket, on the bearing cap and with each other reduced and thereby the sliding ability of the insert body  increased so that a conversion of excitation energy of the axial vibrations in a sliding movement of the insert body with little Friction losses, d. H. with little energy transfer to the adjacent bearing parts and thus an improved damping of the Vibration excitation is achieved. The lubricity of the one Position body can, for example, by lubricating them Surfaces are promoted with lubricants.

In a further embodiment according to claim 5, the inlet body attached to the bearing bracket with the bearing cover. Thereby is a rotation of the insert body with the rotating cure belwelle and the associated wear between Insert body and bearing shell avoided.

Regardless of the attachment, the insert body can deflect conditions in the longitudinal direction of the crankshaft in the form of micro movements execute conditions so that a mobility of the insert body in Longitudinal direction of the crankshaft guaranteed within narrow limits is.

In the following description of the drawing, an exec Example of the invention explained in more detail.

It shows:

Fig. 1, a crankcase with a crankshaft bearing with a sheet bodies in cross section,

Fig. 2 Fig. 1 in a longitudinal section with a schematically given operating principle of the damping of the Axialschwingungsanre supply in the camp.

In Fig. 1, a bearing 2 for a crankshaft 3 is arranged in a crankcase 1 , which is designed as a plain bearing.

The bearing 2 comprises a bearing housing 4 , which consists of a molded on the crankcase 1 bearing bracket 5 and by means of Be fastening screws 6 with this to form a separating joint 7 screwed bearing cap 8 .

Furthermore, the bearing 2 comprises a bearing shell formed from two semi-cylindrical halves 9 , 10 , in which the crankshaft 3 is supported to form a lubricating gap 11 in the bearing.

The bearing shell half 9 is arranged in the bearing block 5 and the bearing half 10 in the bearing cap 8 , the parting plane of the two halves 9 , 10 being in the parting line 7 .

Between the bearing shell and the bearing housing 4 , a gap 12 is provided, in which an insert body 13 made of an inelastic material is inserted. The insert body 13 consists of two shell halves 14 , 15 corresponding to the bearing shell and is attached to the outside of the bearing shell in the sliding fit.

In the gap 12 is another, two shell halves 16 , 17 existing in the same shape as the insert body 13 A insert body 18 is used, which is attached to this outside and at the same time on the bearing housing 4 in the sliding seat. The Einlagekör by 13 , 18 are thus arranged together, on the bearing housing 4 and on the bearing shell in the sliding seat.

Laterally, the shell halves 14 , 15 , 16 , 17 of the insert body by 13 , 18 have longitudinal flanges 19 , 20 running parallel to the parting line 7 , via which the insert bodies 13 , 18 are screwed together with the bearing cover 8 to the bearing bracket 5 by means of the fastening screws 6 .

The insert bodies are preferably made of gray cast iron or steel, with light metal engines in particular, one with increasing Temperature increase in the bearing clearance caused by the different expansion coefficients of the materials be can be limited.

At a longitudinal section of the crankcase 1, the attenuation characteristic of the excitation is shown in Fig. 2 of the excited by the engine combustion noise axial oscillations of the crankshaft 3 se for Kurbelgehäu indicated 1 and the bearing cap 8 back and schematically illustrated by adjacent double arrows, the lengths of which a measure of the strength of the axial vibration designate at the bearing point. The formation of the lubrication gap 11 leads to a damped transmission of the axial vibrations of the crankshaft 3 to the bearing shell. Since the abutting on the bearing shell A position body 13 can perform micro-movements in the longitudinal direction of the crankshaft 3 in its attachment, the already damped axial vibrations experience a further damping by the conversion of part of the excitation energy into a sliding movement of the insert body 13 , which is caused by the arrangement of the inlet body 18 is further enlarged towards the outside. The overall vibration excitation of the crankcase 1 adjoining the insert bodies 13 , 18 via the bearing housing 4 is thus low, which leads to a greatly reduced airborne sound radiation.

Claims (6)

1. Bearing for a crankshaft of an internal combustion engine with egg NEM arranged on the crankcase bearing housing, which comprises a bearing block and an attachable to this bearing cover, further with a bearing shell used in the bearing housing and with an arranged between the bearing housing and bearing shell insert body made of an inelastic material for silencing of the combustion engine transferred to the crankcase, characterized in that the insert body ( 13 , 18 ) is slidably mounted in the longitudinal direction of the crankshaft between the bearing shell and the bearing housing ( 4 ) in the assembled bearing, such that it is in operation on the bearing acting loads as Gan zes micro movements in the longitudinal direction of the crankshaft can perform. 2. Bearing according to claim 1, characterized in that the bearing shell is completely enclosed by the insert body ( 13 , 18 ). 3. Bearing according to one of claims 1 or 2, characterized in that the bearing shell of insert bodies ( 13 , 18 ) is closed in several layers. 4. Bearing according to one of claims 1 to 3, characterized in that the insert body ( 13 , 18 ) consists of two semi-cylindrical halves ( 14 , 15 , 16 , 17 ) formed corresponding to the La shell. 5. Bearing according to one of claims 1 to 4, characterized in that the insert body ( 13 , 18 ) together with the bearing cover ( 8 ) are attached to the bearing bracket ( 5 ). 6. Bearing according to one of claims 1 to 5, characterized in that the insert body ( 13 , 18 ) laterally have longitudinal flanges ( 19 , 20 ), via which they are screwed together with the bearing cover ( 8 ) on the bearing bracket ( 5 ).