DE102022119407A1 - Surface molding and motor vehicle with at least one surface molding - Google Patents

Abstract

A surface molded part of an underbody cladding or a thermal insulation cladding (20) for a motor vehicle (1) with a vehicle body (10) which has a lower body floor (12) with a body floor wall (13) which is provided with at least one indentation (14), wherein the surface molding (2, 2') is provided in or under the indentation (14), whereby a cavity (15) at least partially encompasses the indentation (14) between the surface molding (2, 2') and the body floor (12). is formed, is characterized in that the surface molding (2, 2') has, on its upper side (21) facing the body floor wall (13), a plurality of webs (23, 23', 23'', 23'' that are spaced apart relative to one another. ', 23''''), battlements (24) and/or rows of battlements (25).

Description

The invention relates to a surface molding of an underbody cladding or a thermal insulation cladding for a motor vehicle according to the preamble of claim 1. It further relates to a motor vehicle equipped with at least one such surface molding.

Vehicle parts that move in rotation, in particular drive components, generate sound waves, some of which are emitted directly as airborne sound and some of which are passed on as structure-borne sound to other vehicle parts that are in physical contact with the moving vehicle parts and are converted by them into audible airborne sound. This airborne noise can be unpleasant for both vehicle passengers and people outside.

A practical example is noise emissions in rear-wheel drive vehicles, which arise due to gear meshing in the rear axle gear and are perceived as unpleasant airborne noise (so-called rear axle gear whine) in the passenger compartment by the excited cardan shaft that couples the front drive components to the rear axle gear.

To prevent or reduce the sound transmission of engine noise and driving noise into the vehicle cabin, insulating materials are usually attached to the body walls. However, effective passive measures through sound insulation are not possible everywhere due to a lack of installation space. For example, there is not enough space available in the vehicle's cardan tunnel, neither on the outside nor on the inside of the body floor wall, to install thick sound insulation pads.

The object of the present invention is to provide a generic surface molding that not only forms a cavity cover and/or a thermal shield, but also enables noise reduction.

This task is solved with the features of patent claim 1.

A surface molding of an underbody panel or a thermal insulation panel for a motor vehicle with a vehicle body that has a lower body floor with a body floor wall which is provided with at least one indentation, the surface molding being provided in or under the indentation, whereby between the surface molding and the body floor a cavity is formed that at least partially encompasses the indentation, is characterized in that the surface molding is provided on its upper side facing the body floor wall with a plurality of webs, pinnacles and/or rows of pinnacles that are spaced apart relative to one another.

The provision of the webs, crenellations and/or rows of crenellations on the upper side of the surface molding directed towards the body floor wall, i.e. towards the cavity formed between the surface molding and the body floor wall, disrupts the propagation of standing waves in this cavity and thus reduces the generation of sound. The cavity is acoustically influenced by this structure in such a way that a standing wave that forms in the cavity is changed in such a way that the noise in the interior is significantly reduced. This change is achieved by applying the webs, pinnacles and/or rows of pinnacles to the surface molding, with their position, their shape, their size and/or their relative distance from one another being based on the wavelengths of the sound to be suppressed, for example the sound emitted by the cardan shaft a cardan tunnel.

Further preferred and advantageous design features of the surface molding according to the invention are the subject of subclaims 2 to 9.

The webs or rows of battlements preferably run parallel to one another. Further preferably, the webs or rows of battlements are evenly spaced laterally from one another. Furthermore, it is advantageous if the lateral distance between the webs or rows of crenellations corresponds to the wavelength or a fraction or an even multiple of the wavelength of a standing acoustic wave forming in the cavity.

In a particularly preferred embodiment of the invention, which can be combined with other embodiments, the webs or rows of crenellations each extend in a plane that is essentially perpendicular to the upper side of the surface molding that faces the body floor wall. This plane and thus the respective web or the respective row of battlements extends, for example, in the vehicle's transverse direction Y, which is particularly advantageous if the direction of propagation of the standing wave is in the vehicle's longitudinal direction X. The course of the webs or rows of pinnacles can also be directed in any other direction if this can achieve the desired disturbance of the standing wave.

It is also advantageous if the height of the webs, pinnacles or rows of pinnacles, measured from the top of the surface molding, is the same along the respective course. In addition, it can also be advantageous if the respective height of at least two adjacent webs, pinnacles or rows of pinnacles, measured from the top of the surface molding, is the same.

Advantageously, the webs or rows of battlements can run in the transverse direction of the vehicle or in a direction that has a, preferably dominant, directional vector pointing in the transverse direction of the vehicle.

According to a preferred application of the invention, the surface molding is designed as a thermal insulation element of at least part of an exhaust system.

The invention is also directed to a motor vehicle with at least one surface molding according to the invention.

Preferred exemplary embodiments of the invention with additional design details and further advantages are described and explained in more detail below with reference to the accompanying drawing.

• 1 eine vereinfachte Querschnittsansicht durch einen Ausschnitt eines Kraftfahrzeug-Karosseriebodens mit einem erfindungsgemäßen Flächenformteil;
• 2 eine perspektivische Draufsicht auf ein erfindungsgemäß ausgestaltetes Flächenformteil und
• 3 eine alternative Ausführungsform eines erfindungsgemäßen Flächenformteils in der Querschnittsansicht der 1.

It shows:

• 1 a simplified cross-sectional view through a section of a motor vehicle body floor with a surface molding according to the invention;
• 2 a perspective top view of a surface molding designed according to the invention and
• 3 an alternative embodiment of a surface molding according to the invention in the cross-sectional view 1 .

1 shows a simplified cross-sectional view of a section of a lower body floor 12 of a vehicle body 10 of a motor vehicle 1. The body floor 12 has a body floor wall 13, which in the area of the vertical vehicle longitudinal center plane XZ forms a tunnel 11 running in the vehicle longitudinal direction X as an upwardly curved indentation 14 of the body floor 12 .

A thermal insulation cladding 20 designed as a surface molding 2 is inserted into the tunnel 11 as an insulation insert. Which is fastened with its side edges 21 ', 21" to the body floor wall 13 and which extends transversely through the cardan tunnel 11 and in the vehicle's longitudinal direction the tunnel 11 forming part of the body floor wall 13 are formed.

The surface molding 2 forming the insulation cladding 20 has a wavy cross-sectional contour with two upwardly directed wave crests 20', 20" and a wave trough 20"' located between them. The wave trough 20''' forms a trough 22 running in the vehicle's longitudinal direction X, which at a distance surrounds a cardan shaft 16 of the motor vehicle 1 along a lower peripheral region. The wave crests 20 ', 20" each rise above an exhaust pipe 17, 18 of an exhaust system 19 of the motor vehicle 1 and surround an upper peripheral region of the respectively assigned exhaust pipe 17, 18, wherein the insulation cladding 20 is spaced apart from both exhaust pipes 17, 18. Such insulating inserts are well known to those skilled in the art.

The surface molding 2 forming the insulation cladding 20 here has, on its upper side 21 facing the body floor wall 13, webs 23, 23', 23'', 23''', 23'''' running in the vehicle transverse direction Y ( 2 ) provided, the height of which extends essentially vertically out of the top 21 upwards towards the body floor wall 13. In their longitudinal direction, the webs 23, 23 ', 23'', 23''', 23'''' in the example shown run in the transverse direction of the vehicle Y and thereby follow the wave shape of the surface molding 2 shown here.

As it appears in the perspective view of the 2 can be seen, a plurality of webs 23, 23 ', 23'', 23''', 23'''', preferably evenly spaced from one another in the vehicle's longitudinal direction The webs 23, 23 ', 23'', 23''', 23'''' can also be provided along the entire length of the surface molding 2.

3 shows one of the in a simplified cross-sectional view 1 corresponding section of a lower body floor 12 with a modified surface molding 2 '. Instead of the webs, rows of pinnacles 24 are arranged on the top 21 of the surface molding 2 '. The webs 23, 23 ', 23'', 23''', 23'''' of the embodiment of 1 are here each interrupted along their respective longitudinal extent by gaps 26 and form rows of battlements 25. The length of a respective battlement 24 in the longitudinal extent of a row of battlements 25 preferably corresponds to the length of a gap 26 existing between two adjacent battlements 24.

However, the battlements 24 do not have to - as in 3 is shown - be arranged in rows, but can also be distributed, for example in rows of battlements next to each other with the battlement position offset from one another. In addition to a battlement of a row of battlements, the gaps between two battlements adjacent in the longitudinal direction of the rows of battlements arranged to the left and / or right of it are then provided. It is also possible to distribute the battlements arbitrarily over the surface 21.

The invention is not limited to the above exemplary embodiments, which only serve to generally explain the core idea of the invention. Within the scope of protection, the device according to the invention can also assume embodiments other than those described above. The device can in particular have features that represent a combination of the respective individual features of the claims.

Reference numerals in the claims, the description and the drawings are only intended to facilitate the understanding of the invention and are not intended to limit the scope of protection.

REFERENCE SYMBOL LIST

1

motor vehicle

2

Surface molding

2'

Surface molding

10

Vehicle body

11

Cardan tunnel

12

Body floor

13

Body floor wall

14

indentation

15

cavity

16

propeller shaft

17

exhaust pipe

18

exhaust pipe

19

Exhaust system

20

Insulation cladding

20'

Wellenberg

20''

Wellenberg

21

Top

21'

side edge

21''

side edge

22

trough

23

web

23'

web

23''

web

23'''

web

23''''

web

24

Pinnacle

25

Row of battlements

26

gap

X

Vehicle longitudinal direction

XZ

vertical vehicle longitudinal center plane

Y

Vehicle transverse direction

Claims (10)

Surface molding of an underbody cladding or a thermal insulation cladding (20) for a motor vehicle (1) with a vehicle body (10) which has a lower body floor (12) with a body floor wall (13) which is provided with at least one indentation (14), whereby the surface molding (2, 2') is provided in or under the indentation (14), whereby a cavity (15) which at least partially encompasses the indentation (14) is formed between the surface molding (2, 2') and the body floor (12). is, characterized in that the surface molding (2, 2') is provided on its upper side (21) facing the body floor wall (13) with a plurality of webs (23, 23', 23'', 23''', 23) which are spaced apart relative to one another ''''), battlements (24) and/or rows of battlements (25). Surface molding according to Claim 1 , characterized in that the webs (23, 23 ', 23'', 23''', 23'''') or rows of battlements (25) run parallel to one another. Surface molding according to Claim 2 , characterized in that the webs (23, 23 ', 23'', 23''', 23'''') or rows of battlements (25) are evenly spaced laterally from one another. Surface molding according to Claim 3 , characterized in that the lateral distance of the webs (23, 23', 23'', 23''', 23'''') or rows of battlements (25) from one another is the wavelength or a fraction or an even multiple of the wavelength of one corresponds to the standing acoustic wave forming in the cavity. Surface molding according to one of the preceding claims, characterized in that the webs (23, 23', 23'', 23''', 23'''') or crenellated rows (25) are each located essentially at right angles to the body floor wall dung (13) facing top (21) of the surface molding (2, 2 '). Surface molding according to one of the preceding claims, characterized in that the height of the webs (23, 23 ', 23'', 23''', 23''''), battlements (24) or rows of battlements (25), measured from the Top (21) of the surface molding (2, 2 '), is the same along their respective course. Surface molding according to one of the preceding claims, characterized in that the respective height of at least two adjacent webs (23, 23 ', 23'', 23''', 23''''), battlements (24) or rows of battlements (25) , measured from the top (21) of the surface molding (2, 2 '), is the same. Surface molding according to one of the preceding claims, characterized in that the webs (23, 23 ', 23'', 23''', 23'''') or crenellated rows (25) in the vehicle transverse direction (Y) or in a direction has a preferably dominant direction vector pointing in the transverse direction of the vehicle (Y). Surface molding according to one of the preceding claims, characterized in that the surface molding (2, 2') is designed as a thermal insulation element of at least part of an exhaust system (19). Motor vehicle with at least one surface molding (2, 2') according to one of the preceding claims.

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