DE102014226955A1 - Attachment for connection to a component and method for connecting the attachment to the component - Google Patents

Abstract

The invention relates to an attachment for connection to a component, wherein the attachment has to be welded to the component by means of torsional ultrasonic welding welding section (1), wherein the welding section (1) has a contact surface (A) for contact with a Torsionssonotrode and an opposite welding surface Has connection with the component, and wherein the welding portion (1) is at least partially surrounded by an outer vibration decoupling zone (2). It is further provided according to the invention that the welded portion (1) is annular and is at least partially bounded by an annular inner vibration decoupling zone (3).

Description

The invention relates to an attachment for connection to a component and to a method for connecting the attachment to the component.

An attachment according to the preamble of claim 1 is known from EP 2 246 178 B1 known. The known attachment is designed in the manner of a square plate, which has a square or circular welding section in the center. The welding section is surrounded by a vibration decoupling zone, which is formed by openings or material thinning. The vibration decoupling zone is in turn surrounded by an outer attachment portion. To produce a connection between such an attachment and a component, the attachment is placed on a predetermined attachment portion of the component. Subsequently, pressure is applied to the welding section by means of a torsion sonotrode so that a welding surface of the welding section is pressed against the mounting section. Finally, a torsional ultrasonic vibration is introduced by means of the torsion sonotrode into the welding section, whereby the welding surface is intended to merge with the fastening section. In practice, however, has shown that with the known attachment a weld sufficient strength is not reliable to produce.

To overcome this drawback, it has also been attempted to increase the pressure and / or energy of the induced ultrasonic vibration applied to the welding surface. This allows for certain geometries of the attachment manufacturing a sufficiently strong welded joint. However, it can not be predicted in practice for which geometries of add-on parts a reliable welded connection can be produced. Moreover, in particular, the increase of the introduced ultrasonic energy causes a surface of the component located opposite the fixing section to deform.

Such deformation is not tolerable in practice if this surface is a visible surface of the component. If the surface has been provided with a coating before the connection with the attachment is made, an increase in the ultrasound energy introduced will also destroy or impair the coating layer. Even that is not tolerable in practice.

The object of the present invention is to eliminate the disadvantages of the prior art. In particular, an attachment is to be specified which can be securely and reliably attached to a component by means of a torsional ultrasonic welding process. According to an object of the invention, the attachment should be designed such that in the production of a welded joint, an opposite surface of the component is not affected. Another object of the invention is to provide a method of attaching an attachment to a component by torsional ultrasonic welding.

This object is solved by the features of claims 1 and 16. Advantageous embodiments of the invention will become apparent from the features of claims 2 to 15 and 17 to 22nd

According to the invention it is proposed that the welding section is annular and is limited at least in sections by an annular inner vibration decoupling zone. - In departure from the prior art, the weld portion is no longer in the manner of a circular surface, but in the manner of an annular surface in plan view of the attachment. The annular surface is delimited, in further departure from the prior art, both from the outer and from an annular inner vibration decoupling zone.

An attachment according to the invention can be securely and reliably welded to a component by means of torsional ultrasonic welding. The production of the welded connection succeeds in comparison to the prior art using a reduced ultrasonic power. An opposite visible surface of a component is not affected by the production of the ultrasonic welding connection. This is advantageously the case even if the opposite visible surface is already provided with a lacquer layer.

An attachment according to the subject of the present invention must - in departure from the prior art - are no longer rotationally symmetrical within the weld section. Ie. an inner attachment portion surrounded by the inner vibration isolation zone may also have an asymmetric weight distribution with respect to an axis of rotation of the torsion sonotrode. This increases the freedom in the design of the attachment. The attachment can be designed in particular as a holder for elements to be attached thereto, wherein retaining elements provided on the attachment can be designed corresponding to the element to be held.

According to an advantageous embodiment, the inner vibration decoupling zone at least partially surrounds an inner attachment section. Preferably, the inner attachment portion is completely continuous circumferential inner vibration decoupling zone largely decoupled with respect to the vibration transmission. As a result, an ultrasonic energy introduced into the welding portion is largely transmitted to the welding surface. Thus, with reduced energy consumption, the production of a welded connection is safe and reliable.

According to a further advantageous embodiment, at least in sections, an outer attachment section extends from the outer vibration decoupling zone. Also, the outer attachment portion need not be rotationally symmetric with respect to the axis of the annular inner vibration isolation zone. Advantageously, the outer vibration isolation zone is surrounded by the outer attachment portion. The outer attachment portion is expediently rotationally symmetrical with respect to the axis of the inner vibration decoupling zone.

The inner attachment portion may include a first aperture disposed concentrically with the inner vibration isolation zone. The first breakthrough may be configured in particular circular. By providing a central first opening in the attachment weight can be saved.

According to a further advantageous embodiment, the welding section and the outer attachment section form a common plate. The weld portion may have a thickness in the range of 1.0 to 3.0 mm, preferably in the range of 1.2 to 1.6 mm. The outer attachment portion is in particular designed such that it rests in the attached state on the inner surface of the component. The outer attachment portion can be used in particular for producing a bond with the component. Such a bond may be required, for example, in case of repair.

According to a further embodiment, the inner attachment portion has a plurality of concentrically arranged with respect to the first opening, extending from the plate mounting portions for securing a corresponding to the mounting portions formed member. The element may, for example, be a distance sensor of a motor vehicle or the like. The attachment portions may include substantially perpendicularly extending from the plate holding and locking tongues.

According to a further, particularly advantageous embodiment of the invention, the inner and / or outer vibration decoupling zone is formed by a plurality of second openings or by one or more material thinning. The second openings may be round, trapezoidal, oval or slit-shaped. The configuration of the second openings depends on the rigidity of the material used for the production of the attachment and its thickness.

Advantageously, the second openings are formed oval. A long axis of the oval-shaped second openings in this case advantageously extends radially with respect to the axis of the welding section. The long axis has expediently a length of 1.5 to 6.0 mm. A short axis extending perpendicular to the long axis may have a length in the range of 0.5 to 3.0 mm. In particular, it may also be that a first breakdown area of the first openings is smaller than a second breakdown area of the second openings. In this way, a particularly effective decoupling of the welding section with respect to the inner and outer attachment sections can be achieved.

The vibration decoupling zones may also be formed by material thinning in the manner of a groove.

According to a further advantageous embodiment, the welding surface is formed by at least one rib extending from the welding section. The rib expediently extends concentrically with the axis of the inner vibration decoupling zone. It can be formed circumferentially. The rib can also be formed from a plurality of circumferentially arranged rib sections. Conveniently, the rib is formed tapering in cross section. As a result, a contact area between the rib and the component at the beginning of the torsional ultrasonic welding process is particularly low, so that initially act a high ultrasonic energy and a high pressure on the contact surface. This facilitates and accelerates the welding process.

According to a further advantageous embodiment, which is considered independent of the claimed invention as a separate invention, it may also be that varies in plan view of the rib whose width along the extension direction. Due to a possibly asymmetrical design of the inner attachment portion, it may be that along the extension direction of the rib, the intensity introduced on the contact surface changes. This can be counteracted by changing the width of the rib: the higher an intensity introduced onto a rib section, the broader the rib is formed in this rib section. It can thus be achieved a homogeneous intensity distribution along the extension direction of the rib. For the ratio of a minimum width B _min to a maximum width B _{max of} the rib is suitably the following relationship: B _max = n × B _min , where n is a number in the range of 1.2 and 7.0.

As a result of the width of the rib which is changed in the circumferential direction, it is also advantageously achieved that, during the ultrasonic welding process, a distance between the component and an underside of the attachment facing the component remains essentially the same. Ie. the attachment can not get into an undesirable inclination with respect to the component during the ultrasonic welding process. By the proposed embodiment of the rib can be ensured that the attachment is mounted on the component, that the underside of the attachment parallel to an opposite upper side of the component.

According to another aspect of the invention, a method is proposed for attaching an attachment to a component with the following steps:

Placing the attachment according to the invention on a predetermined attachment portion of the component,

Applying a predetermined pressure by means of a Torsionssonotrode on the contact surface, so that the welding surface is pressed against the mounting portion, and
Introducing a torsional ultrasonic vibration by means of the torsion sonotrode in the welding section, so that the welding surface merges with the attachment portion.

According to the invention, the torsional ultrasonic welding method is now used for producing a connection of an attachment with a component, wherein the attachment has a ring-shaped welded portion and is at least partially bounded by an annular inner vibration decoupling zone. When applying the torsional ultrasonic welding method to the attachment proposed according to the invention, it is possible to reliably and reliably produce an ultrasonic welded connection with the component. In contrast to the prior art, a lower vibration energy must be coupled into the component. A mounting surface of the component opposite the mounting portion remains unaffected, even if it is provided with a coating layer.

According to an advantageous embodiment of the invention, the attachment is placed on the component such that a first breakthrough provided therein is aligned with a further breakthrough provided in the component, d. H. the attachment is aligned in its xy plane with respect to the component. In the proposed embodiment, the attachment can serve as a holder for an element to be fastened therein, which passes through the opening and the further breakthrough.

According to a further embodiment, at least one vibration damping element is brought into contact with the outer and / or the inner attachment section before the introduction of the torsional ultrasonic vibration. A first vibration damping element may be a centering device, which passes through the first breakthrough and the further breakthrough after placement of the attachment. Advantageously, with the centering the attachment with respect to the component with respect to an xy plane and in a predetermined angular position with respect to a perpendicular to the xy plane extending z-axis aligned. This can ensure that, for example, a sensor inserted in the attachment, for example a distance sensor, is held in a predetermined position relative to the component.

A second vibration damping element may be brought into contact with the outer attachment portion prior to making the ultrasonic weld joint. With the first and / or the second vibration damping element of the relevant attachment portion is held relative to the component. An oscillation caused by the torsion sonotrode is damped or completely suppressed by the vibration damping elements in the respective attachment sections.

According to a further particularly advantageous embodiment of the method, the component is provided before placing the attachment on a side opposite the mounting portion side with a paint job. Thus, in particular, a method for producing a motor vehicle bumper can be carried out particularly efficiently. A conventional procedure, in which attachments for receiving distance sensors after painting the bumper are attached by means of an adhesive bond can be maintained. Ie. With the method according to the invention, it is also possible, after the production of a paint finish of the bumper by means of the proposed fastening method to attach the attachment according to the invention. The fastening method according to the invention can be performed faster, easier and cheaper.

Embodiments of the invention will be explained in more detail with reference to the drawings. Show it:

1 a perspective view of a first attachment,

2 a plan view of the attachment according to 1 .

2a a detail view of a second breakthrough in 2a .

2 B a detailed view of a second embodiment of a second breakthrough,

2c a detailed view of a third embodiment of the second breakthrough,

2d a detailed view of a fourth embodiment of the second breakthrough,

3 the amplitude of an ultrasonic vibration introduced to the welding section above the in 2 shown section,

4 a plan view of a second attachment,

5 a partial sectional view along the section line AA 'in 4 and

6 a bottom view of a third attachment.

In the 1 and 2 has a first attachment made of plastic a welding section 1 for contact with a torsion sonotrode (not shown). The welding section 1 has a substantially annular contact surface A for contact with the Torsionssonotrode. The contact surface A extends in an xy plane. Opposite the contact surface A is a (not visible here) welding surface for connection to a (not shown here) component. The welding section 1 is from an outer vibration decoupling zone 2 and an inner vibration decoupling zone 3 limited. The outer vibration decoupling zone 2 may also be formed in sections by an edge R of the attachment.

With the reference number 4 is an inner attachment portion referred to, which is designed here in the manner of a pipe socket. The outer vibration decoupling zone 2 is partially surrounded by an outer attachment section 5 , The welding section 1 is formed substantially annular. An axis of the annular welding section 1 is in 2 denoted by the reference z. The axis Z extends perpendicular to the xy plane.

Inside the inner attachment section 4 is a first breakthrough 6 formed, which is formed here circular. The first breakthrough 6 is arranged concentrically with respect to the axis z.

The inner one 3 as well as the outer vibration decoupling zone 2 are each of a plurality of adjacently arranged oval second openings 7 educated. The oval second breakthroughs 7 each form concentric with respect to the axis X annular or ring-shaped zones.

Neighboring second breakthroughs 7 the outer vibration decoupling zone 2 are arranged at a first distance D1 of 0.5 to 3.0 mm, adjacent second openings 7 the inner vibration decoupling zone 3 at a second distance D2 of 1.0 to 4.0 mm. The second breakthroughs 7 are in the in 2a shown first embodiment formed oval. They each have a long axis A1 extending in the radial direction and a short axis A2 extending perpendicularly thereto.

The welding section 1 , the inner ones 3 , the outer vibration decoupling zone 2 and the outer attachment section 5 are formed from a plate. A thickness of the welding portion is in the range of 1.0 to 3.0 mm. An angle α between two adjacent second openings 7 is preferably 2 to 5 °, more preferably 3.5 to 4.5 °.

The 2 B to 2d show further embodiments of second breakthroughs 7 ,

At the in 2 B shown second embodiment is the radially extending second aperture 7 slit-shaped, wherein at the short ends of the slot in each case a circular recess 7a is provided. The circular recess 7a serves to reduce voltage spikes and consequent tearing of the second breakthrough 7 in the area of its short ends.

The 2c shows a third embodiment of a turn radially extending second aperture 7 , In this case, the second breakthrough 7 rectangular designed. A jetty 7b between two adjacent second openings 7 here has a trapezoidal shape.

At the in 2d shown fourth embodiment, the second openings 7 trapezoidal shaped in such a way that the slot width increases radially outward. A jetty 7b between two adjacent second openings 7 is designed in this case substantially rectangular. A resulting uniform web width of the webs 7b simplified in constructive Regards the design and layout of the vibration isolation zones 2 . 3 ,

The function of the attachment is now in conjunction with 3 explained in more detail.

To produce an ultrasonic welded connection with a component (not shown here), the attachment is placed on a fastening section of the component. Then, a torsion sonotrode (not shown) is pressed against the seating surface A. Subsequently, a torsional vibration is applied to the welding section by means of the torsion sonotrode 1 transfer. The torsional oscillation oscillates about the axis z, which substantially coincides with a torsion axis of the torsion sonotrode during the production of the welded connection. In 3 is the amount of a corresponding amplitude of the torsional vibration over the corresponding zones of the in 2 shown attachment. How out 3 it can be seen, the amplitude and thus the transmitted vibration energy falls within the vibration decoupling zones 2 and 3 strong. Ie. via the vibration decoupling zones 2 . 3 hardly any vibration energy is applied to the inner attachment section 4 and the outer attachment section 5 transfer.

An entry of vibrational energy into the inner attachment section 4 and / or the outer attachment portion 5 can be further reduced by vibration damping elements with the inner attachment portion 4 and / or the outer attachment portion 5 be brought into frictional contact. This ensures that one on the inner 4 and / or outer attachment section 5 dampened during the ultrasonic welding process vibration is attenuated.

4 shows a plan view of a second attachment. The second attachment R is the edge by a circumferential wall 8th formed, which with respect to the outer attachment portion 5 acts as a vibration damping element. The inner attachment section 4 Here is several of the particular of the welding section 1 forming plate extending mounting portions 9 educated. The attachment sections 9 include functional elements, eg. B. locking tongues and columnar support sections, which are each arranged concentrically with respect to the axis X. The attachment sections 9 are designed corresponding to the housing of a distance sensor (not shown here), which can be fixed therein positively and / or non-positively.

5 shows a partial sectional view along the line AA 'in 4 , How out 5 clearly shows, is opposite the Aufsetzfläche A of the welding section 1 a welding surface is provided which has a circumferential rib 10 having. The welding section 1 is in the radial direction on both sides by the second openings 7 the inner vibration decoupling zone 3 and the outer vibration isolation zone 2 limited. The outer attachment section 5 is with the perimeter wall 8th Mistake. The inner attachment section is made up of the retaining elements 9 formed, which from the plate-shaped welding section 1 extend.

6 shows a schematic bottom view of a third attachment. As can be seen, the rib can 10 have a minimum width B _min and a maximum width B _max in the circumferential direction. The minimum B _min is, for example, 0.5 to 1.5 mm and the maximum width B _{max is} 1.0 to 2.5 mm. As in 6 shown, the rib can 10 have two opposite minimum widths B _min and two opposite maximum widths B _max . By in the extension direction of the rib 10 changing width, a homogeneous energy distribution can be achieved when coupling the ultrasonic vibration.

LIST OF REFERENCE NUMBERS

1

welding portion

2

outer vibration decoupling zone

3

inner vibration decoupling zone

4

inner attachment section

5

outer attachment section

6

first breakthrough

7

second breakthrough

7a

circular recess

7b

web

8th

wall

9

attachment section

10

rib

A

touchdown

A1

long axis

A2

short axis

B _min

minimum width

B _max

maximum width

D1

first distance

D2

second distance

R

edge

xy

level

z

axis

α

angle

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 2246178 B1 [0002]

Claims (22)

Attachment for connection to a component, wherein the attachment part to be welded to the component by means of torsional ultrasonic welding welding section ( 1 ), wherein the welding section ( 1 ) has a contact surface (A) for contact with a Torsionssonotrode and an opposite welding surface for connection to the component, and wherein the welding portion ( 1 ) at least in sections from an outer vibration decoupling zone ( 2 ), characterized in that the welding section ( 1 ) annularly formed and at least partially by an annular inner vibration decoupling zone ( 3 ) is limited. Attachment according to claim 1, wherein the inner vibration decoupling zone ( 3 ) at least in sections an inner attachment section ( 4 ) surrounds. Attachment according to one of the preceding claims, wherein the outer vibration isolation zone ( 2 ) at least in sections an outer attachment section ( 5 ). Attachment according to one of the preceding claims, wherein the outer vibration decoupling zone ( 2 ) from the outer attachment section ( 5 ) is surrounded. Attachment according to one of the preceding claims, wherein the inner attachment portion ( 4 ) one concentric with an axis (z) of the welding section ( 1 ) arranged first breakthrough ( 6 ) having. Attachment according to one of the preceding claims, wherein the welding section ( 1 ) and the outer attachment section ( 5 ) form a common plate. Attachment according to one of the preceding claims, wherein the welding section ( 1 ) has a thickness in the range of 1.0 to 3.0 mm, preferably in the range of 1.2 to 1.6 mm. Attachment according to one of the preceding claims, wherein the inner attachment portion ( 4 ) several regarding the first breakthrough ( 6 ) concentrically arranged, extending from the plate mounting portions ( 9 ) for fixing a corresponding to the attachment portion ( 9 ) formed element. Attachment according to one of the preceding claims, wherein the inner ( 3 ) and / or outer vibration decoupling zone ( 2 ) by a plurality of second breakthroughs ( 7 ) or formed by one or more material thinning. Attachment according to one of the preceding claims, wherein the second openings ( 7 ) are round, oval or slit-shaped. Attachment according to one of the preceding claims, wherein a long axis (A1) of the oval-shaped second openings ( 7 ) radially with respect to the axis (z) of the welding section ( 1 ) runs.  Attachment according to one of the preceding claims, wherein the long axis (A1) has a length of 1.5 to 6.0 mm.  Attachment according to one of the preceding claims, wherein the at least one material thinning in the manner of a groove is formed. An attachment according to one of the preceding claims, wherein the welding surface is defined by at least one of the welding portion ( 1 ) extending rib ( 10 ) is formed. Attachment according to one of the preceding claims, wherein a width (B _min , B _max ) of the rib ( 10 ) changes along the direction of extension. Method for fastening an attachment to a component with the following steps: placing the attachment according to one of the preceding claims on a predetermined attachment portion ( 9 ) of the component, applying a predetermined pressure by means of a Torsionssonotrode on the contact surface (A), so that the welding surface against the mounting portion ( 9 ) and introducing a torsional ultrasonic vibration by means of the torsion sonotrode into the welding section ( 1 ), so that the welding surface with the attachment portion ( 9 ) merges. The method of claim 16, wherein the attachment is placed on the component such that a therein provided first breakthrough ( 6 ) is aligned with a provided in the component further breakthrough. A method according to claim 16 or 17, wherein prior to the initiation of the torsional ultrasonic vibration at least one vibration damping element with the outer ( 5 ) and / or inner attachment section ( 4 ) is brought into contact. Method according to one of claims 16 to 18, wherein a first vibration damping element is a centering means, which after the attachment of the attachment the first breakthrough ( 6 ) and the further breakthrough.  Method according to one of claims 16 to 19, wherein aligned with the centering means, the attachment part with respect to the component both in an xy plane and in a predetermined angular position with respect to a perpendicular to the xy plane z-axis (z). Method according to one of claims 16 to 20, wherein the component before attaching the attachment to a the mounting portion ( 9 ) opposite side is provided with a paint job.  Method according to one of claims 16 to 21, wherein the component is a bumper of a motor vehicle and the attachment is a fastening means for fixing a distance sensor.

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