LU100866B1

LU100866B1 - A method of coupling a first socket part to a second socket part using a friction piece and clamping tool usable in such a method

Info

Publication number: LU100866B1
Application number: LU100866A
Authority: LU
Inventors: Pinto José Miguel Teixeira; Baptiste Audrezet; Patrick VATIN
Original assignee: Aliaxis R&D Sas
Priority date: 2018-07-03
Filing date: 2018-07-03
Publication date: 2020-01-07

Abstract

The present invention proposes a method of coupling a first socket part to a second socket part comprising the steps of Inserting a first axial end of an intermediate or friction piece into the first socket part along a first interface, wherein the friction piece is distinct from the second socket part, and the friction piece having a main friction body extending between said first axial end and a second axial end, with an outer friction surface at the first and axial ends, and an actuated part there between, and Generating heat locally at the first interface, wherein heat is generated by one of a rotation between the friction piece and the socket part, or vibrations of the friction piece relative to the first socket part, thereby causing welding of friction piece and of the first socket part along the first interface. The present invention further proposes a friction piece usable in such a method and a tool .

Description

F27509LU PORTMANN 1 a © friction piece and clamping tool usable in such a method Applicant: Aliaxis R&D SAS Our Reference: F27509LU Description Cross-reference to related applications None Field of the invention The present invention generally relates to bonding technologies using thermal activation and/or energy supply. More precisely, the present invention relates to a method of a method of coupling a first socket part to a second socket part, a tool for coupling a first socket part to a second socket part, and a friction piece for of coupling a first socket part to a second socket part.

A coupling element designed to allow assembly by induction welding or electrofusion of at least two thermoplastic components is already known from patent application FR 2 748 415 Al. The coupling element includes a body of thermoplastic material in which elastic heating elements, e.g. elastic spiral spring (s), are embedded in a pre-tensioned state. During the welding operation, the elastic heating element melts the material surrounding the elastic heating element. This allows it to then move and transition from its pre-tensioned state to its natural state astride between the two welded parts. Other methods of joining or coupling pipes are known in which adhesives are used for connecting pipes. However, the adhesives comprise chemical substances such as solvents which are prone to evaporate during assembly. It is known, however, that some of the chemical substances may have a negative impact on the environment and/or human health. Industrials are trying to reduce the impact of the industry on the environment and/or the human health, in particular by identifying potential hazardous chemical substances to protect humans and the environment. This is for example one of the objectives of the European 3 juillet 2018

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, 1 regulation entitled Registration, Evaluation, Authorisation and Restriction of Chemicals LU100866 (REACH) Among these chemical substances, solvents are known to have a negative impact.

It is therefore an object of the present invention to provide alternative solution to coupling, in which there is no need for solvent-based adhesives. Summary of the invention To this end, the invention proposes a method of coupling a first socket part to a second socket part comprising the steps of inserting a first axial end of an intermediate or friction piece into | the first socket part along a first interface, wherein the friction piece is distinct from the second socket part, and the friction piece having a main friction body extending between said first axial end and a second axial end, with an outer friction surface at the first and axial ends, and an actuated part there between, and generating heat locally at the first interface, wherein heat is generated by one of a rotation between the friction piece and the socket part, or vibrations of the friction piece relative to the first socket part, thereby causing welding of friction piece and of the first socket part along the first interface The method may further comprise inserting a second axial end of the friction piece opposite | the first axial end into the second socket part along a second interface, generating heat locally at the second interface, wherein heat is generated by one of a rotation of the friction piece, a rotation of the friction piece or vibrations of the friction piece, thereby causing welding of the along the second interface, wherein heat is generated simultaneously at the first interface and at the second interface. The invention further proposes a method of coupling a first socket part to a second socket part comprising the steps of inserting the first socket part into the second socket part along a first interface, wherein the second socket part is provided with a friction piece with main friction body having an inner friction surface extending along the first interface, at the first and axial ends, and a friction actuated part on an outer surface of the socket part, and generating heat locally at the first interface, wherein heat is generated by one of a rotation between the friction piece and the socket part, or vibrations of the friction piece relative to the first socket 3 juillet 2018

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SONNENBERG part, thereby causing welding of friction piece and of the first socket part along the first LU100866 interface.

The present invention advantageously suggests using heating a friction piece by friction or vibration for coupling two socket parts.

The friction piece may be integral with one of the socket part or may be an intermediate piece.

An intermediate piece is easier to rotate, e.g. between a fitting as a first socket part and a tube as a second socket part.

In an aspect, heat is generated by rotation of the friction piece or by vibration of the friction piece, the method comprising applying pressure, by a clamping tool, on the first socket part, to prevent movement of the first socket part during heat generation.

In a further aspect, heat is generated by rotation of the first socket part, the method comprising applying pressure, by a clamping tool, on the friction body of the friction piece, to prevent movement of the friction piece during heat generation.

Heat may be generated by rotation of the friction piece at alternate high frequency small rotations.

In an aspect, the method comprises measuring a torque applied on the friction piece and/or on the first socket part during relative rotation of the friction piece relative to the first socket part.

This allows controlling the welding., by giving a feedback on the quality of the welding.

The torque applied on the friction piece and/or on the first socket part during relative rotation of the friction piece relative to the first socket par will first increase at the beginning of the rotation.

When the bonding material starts to melt, the torque stars decreasing, and keeps decreasing until the bonding material is molten.

The torque therefore gives an indication of the mixing and welding of the bonding materials.

In another aspect, the method comprises providing at least one of a first bonding material on an outer surface of the friction piece, a second material on an inner surface of the first socket part and a third material on an inner surface of the second socket part, wherein the first bonding material, second material, and third bonding material comprises a transition polymer (hot melt). Hot melt polymers are based on thermoplastic polymers., which are solid at room temperature and have a softening or melting temperature which is known to be low, less than 3 juillet 2018 —— ddarc SHUTS a 150°C. Upon solidification, hot melt polymers return to a physical state that has structural LU100866 integrity and can function as an adhesive. By providing a transition polymer, also named hot melt, for the bonding material, one can ensure a lower melting temperature whilst providing a robust coupling thanks to the adhesive properties of melted transition polymers.

The present invention also proposes a friction piece usable in such a method, wherein the friction piece has a friction body with a first axial end and a second axial end opposite the first axial end, the friction body comprises a friction actuated part on its outer surface for rotation or vibration to the friction piece through a friction tool. | 10 The first axial end and/or the second axial end may have a conical shape along the main axis, in particular wherein an inner diameter of the friction body is greater at the center of the friction body than at the first axial end or at the second axial end. A conical shape may help The present invention further proposes a tool usable in a method according to claim 1, the tool comprising a first jaw for clamping the first socket part on the first socket part along a first interface, and an actuating part for actuating the remaining one of the first socket part or the friction piece, wherein the actuating part is configured to rotate the friction piece about said main axis or to rotate the first socket part along said main axis In an aspect, the tool comprises a pressure applying part for applying pressure on the first socket part or the friction piece along the first interface, to increase the friction between the first socket part and the friction piece In yet a further aspect, the tool comprises a torque sensor adapted to detect a torque applied by the actuating part on either one of the socket part or friction piece during rotation of the socket part or friction piece. The actuating part may be a vibration actuating part, configured to rotate the friction piece at alternate high frequency small rotations. Brief Description of the figures 3 juillet 2018 Sn}

Other features and advantages of the present invention will become apparent from the LU100866 description below in conjunction with the accompanying drawings showing an example of an embodiment which include, but are not limited to: Figure 1 is a block diagram of a method of coupling a first socket part to a second socket part according to an embodiment of the present invention; Figure 2 shows a coupling of the first socket part to a second socket part using a method according to another embodiment of the present invention; Figure 3 shows a coupling of the first socket part to a second socket part using a method according to another embodiment of the present invention; Figure 4 shows a friction piece inserted between a first socket part and a second socket part in a method according to another embodiment of the present invention Figures 5 to 6 show a clamping tool usable in a method according to an embodiment of the present invention; In the drawings, identical or similar elements are indicated with identical or similar reference numbers. Figure 1 shows a method of coupling a first socket part 10 to a second socket part 20, described with reference to Figure 2 or Figure 3. The first socket 10 in the example is a pipe element, and the second socket part 20 is a fitting. This is not limiting the invention, and the first socket part and the second part may be two fittings, or two pipe elements.

A friction piece 50 with an outer friction surface 54 and a friction actuated part 55 is provided to the second socket part 20. In the example of Fig. 2, the friction piece 50 is distinct from the second socket part 20. The friction piece 50 has a main friction body 53 extending along a main axis, with a first axial end 51 and a second axial end 52, with the outer friction surface 54 at the first axial ends 51 and 52, and the actuated part 55 in-between. 3 juillet 2018

SONNENBERG £27509LU FORTMANN 6 In the example of Fig. 3 the friction piece is integral with the second socket part 20. In this LU100866 case, the outer friction surface 54 is provided at the inner surface of the second socket part 20, and the friction actuated part 55 is provided at the outer surface of the second socket part 20. In a first step S1, the first axial end 51 of the friction piece 50 is inserted into the socket part along a first interface 12. In an aspect, the first axial end 51 and/or the second axial end 52 has a conical shape along the main axis, with an inner diameter of the friction piece 50 being greater at a center of the 10 friction body 53 than at the first axial end 51 and/or at the second axial end 52, respectively.

The conical shape facilitates the insertion of the socket part 10 and/or the socket part 20 into the axial ends 51, 52, respectively.

Additionally, a conical shape enables to maintain the friction piece in place axially, thereby keeping the pressure homogeneously.

In other words, the conical shape enables the deformation or expansion of the axial ends of the friction piece, resulting in an optimisation of the pressure loss due to the melting of the bonding material.

In a second step S2, heat is generated at the first interface 12, by relative rotation of the friction piece 50 and the first socket part 10 or by vibrations of the friction piece 50 relative to the first socket part 10, or by ultrasound generation, thereby causing welding of friction piece and bonding of the first socket part along the first interface.

More precisely, heat is generated by the relative rotation or vibrations of the outer friction surface 54 of the friction piece 20 with respect to the first socket part 10, at the first interface 12 In the example of Fig. 3, the friction piece 50 is integral with the second socket part 20, the welding of the friction piece 50 along the first interface 12 results directly in the coupling between the first socket part 10 and the second socket part 20. In the example of Fig.2, the friction piece 50 is not integral with the second socket part 20, the method therefore comprises inserting the second axial end 52 into the second socket part 20 part along a second interface 22, and generating heat locally at the second interface 22 (third 3 juillet 2018 N:

SONNENBERG F27509LU FORTMANN 7 step S3). The friction piece fitted between the first socket part and the second socket part is-U100866 illustrated on Fig.4. Preferably, heat is generated by relative rotation of the friction piece 50 with respect to the second socket part 20 or vibrations of the friction piece 50 along the second interface 22, thereby causing welding of friction piece along the second interface 22. Preferably, heat is generated simultaneously at the first interface 12 and at the second interface 22. To do so, the friction piece 50 is rotated when both the first axial end 51 and the second axial end 52 are inserted into the first and second socket parts 10, 20, respectively.

At least one of the friction piece 50, the first socket 10 or the second socket 20 may be provided with a bonding material on its outer surface.

In an embodiment the friction piece 50 comprise a first bonding material at least at its outer surface.

In an embodiment, the first socket part 10 also comprises a second bonding material at least at its outer surface, and the second socket part 20 also comprises a third bonding material at least at its outer surface, respectively.

Preferably, the bonding material is a transition polymer, also named hot melt.

Hot melt polymers are based on thermoplastic polymers., which are solid at room temperature and have a softening or melting temperature which is known to be low, less than 150°C.

Upon solidification, hot melt polymers return to a physical state that has structural integrity and can function as an adhesive.

It is known to use hot melt polymers as glue, wherein the holt melt polymer is applied as a liquid adhesive by extruding, rolling, co-extrusion, bi-injection, in line assembly or spraying the hot melt polymer on the surface of a first object to be assembled and joining with another object is carried out immediately after application.

The second bonding material and/or the third bonding material is also a transition polymer. 3 juillet 2018 -—_—-_"—-_-_—_-_-_--—"—""— "—"—"""———————————————— 77 |

The first, second and third bonding material may be the same material or different transitionLU100866 polymer having different melting properties or temperatures. Similarly, it should be understood that each of the first, second and third bonding materials may comprise different layers of transition polymers.

Advantageously, the melting temperature can remain lower than the melting temperature of the substrate, implying less volume/mass and lower melting temperature, therefor less energy to be provided. As mentioned above, the melting temperature can be up to 150 °C or lower (120, 130, 110, 100...°C). It should be noted that the melting temperature can be tailored by playing with the molecular weight of the hot melt or by adding additives modifying the material viscosity of the hot melt polymer. An example of bonding material that can be used in the coupling elements of the present invention is a Platamid hotmelt, which is well indicated for adhesion with a substrate made of C-PVC. The present invention suggests providing a friction piece with such a transition polymer, and heating via vibration or rotation of the bonding material at the surfaces for pipe couplings or in the plumbing, as described in the following.

The step of applying heat also comprises applying pressure, by a clamping tool 70, on the first socket part 10 and/or on the second socket part 20, to prevent movement of the first socket part 10, respectively the second socket part 20 during heat generation.

An example of clamping tool 70 is shown on Figure 4-6. The clamping tool 70 comprises two clamping jaws 71, 72, to block the first socket part 10 and the second socket part 20, during relative rotation or vibration of the first socket part and second socket part and the friction piece.

The clamping tool 70 comprises a rotation actuating part 75, adapted to interact with the friction actuated part 55 of the friction piece 50 and cause the rotation of the friction piece 50, as seen on Fig. 4-6. 3 juillet 2018

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In the example of Fig. 2 of the present disclosure, the friction actuated part 55 is provided on-U100866 the outer surface of the friction body 53 for interaction with said clamping tool 70. The friction actuated part 55 may have a gear shape to mesh with the rotation actuating part 75.

In the example illustrated in figures 43 to 6, the rotation actuating part 75 is a transmission belt 75 of the tool, but this is not limiting the invention. For example, a double gear actuator, a specific friction shape, are also contemplated.

An actuator 78 is provided on the clamping tool 70, to operate the rotation actuating part 75.

In the examples of Figures 2 to 5, the skilled person understands that the friction piece 50 is a rotative part between the pipe 10 (example of a first socket part) and the fitting 20 (example of second socket part). The friction piece 50 is therefore inserted into the pipe 10 and the fitting 20, which are clamped to ensure a pressure between the pipe 10 and the rotative friction piece 50 and respectively between the fitting 20 and the friction piece 50. When the clamping tool 70 is applying pressure on the pipe 10 and the fitting 20, the pipe 10 and the fitting 20 are prevented from moving during the rotation of the friction piece 50.

When the friction piece 50 rotates, friction is generated friction at the first interface 12 between the friction piece 50 and the pipe 10, respectively at the second interface 22, between the friction piece 50 and the fitting 20. The friction heats locally at said interfaces 12, 22, resulting in the melting of the bonding material of the friction piece 50.

It should be noted that in the embodiments in which the pipe 10 has a second bonding material and the fitting 20 has a third bonding material with transition polymers, the second bonding material and the third bonding material mix themselves under heat creating a fused/welded zone.

In order to control the welding of the first, second and/or third bonding material, the clamping tool 70 is provided with a sensor 80 adapted to measure a torque applied by the rotation actuating part 75 on either one of the first socket part 10, second socket part 20 when applicable, or friction piece 50 during relative rotation of the friction piece 50 with respect to the first socket part 10, or second socket part 20.

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The method therefore comprises measuring a torque applied on the friction piece 50 and/or on U100866 the first socket part 10 during relative rotation of the friction piece relative to the first socket part.

Measuring the torque needed to rotate the friction piece 50, gives a direct feedback on the quality of the welding. Indeed, the skilled person understands that the torque at the beginning of the rotation will be increased and the decreasing of the torque is an indication that the first bonding material is molten, as well as the second bonding material and third bonding material when present. The torque therefore gives an indication of the mixing and welding of the bonding materials, resulting in the coupling of the first socket part 10 with the second socket part 20. A pressure applying part for applying pressure on the first socket part or the friction piece along the first interface, may also be provided, to increase the friction between the first socket part and the friction piece In the examples of Figures 4 to 6, the skilled person understands that the friction piece 50 is a rotated between the pipe 10 (example of a first socket part) and the fitting 20 (example of second socket part), and the clamping tool is provided with a friction actuated part. When the friction piece 50 rotates, friction is generated friction at the first interface 12 between the friction piece 50 and the pipe 10, respectively at the second interface 22, between the friction piece 50 and the fitting 20. The friction heats locally at said interfaces 12, 22, resulting in the melting of the bonding material of the friction piece 50. In another embodiment, heat is generated by vibrations of the friction piece 50, using a clamping tool is provided with a friction actuated part. In this embodiment the clamping tool similar to the clamping tool 70, yet adapted to transmit high frequency back and forth small rotations.

The clamping tool causes the vibrations of the friction piece 50 by means of alternate high frequency small rotations, thereby generating friction at the first interface 12 or second interface 22. It should be noted that energy concentrators can be used. For example, a 3 juillet 2018 -—_—_—_—_-_-_-_- -—_-_-_-_-_ -—_—_—_

SONNENBERG SOW Fora TT frequency of 100-240 Hz may be used, however the frequencies need for vibration welding LU100866 may depend on the material of the first and second socket and/or of the friction piece.

In yet another embodiment heat can be generated by vibrations of the friction piece 50, using a clamping tool provided with a friction actuated part adapted to generate ultrasound. In this embodiment the clamping tool causes the vibrations of the friction piece 50 by means of ultrasounds, thereby generating friction at the first interface 12 or second interface 3 juillet 2018

Claims

friction piece and clamping tool usable in such a method Applicant: Aliaxis R&D SAS Our Reference: F27509LU Claims

1. Method of coupling a first socket part to a second socket part comprising the steps of - Inserting a first axial end of an intermediate or friction piece into the first socket part along a first interface, wherein the friction piece is distinct from the second socket part, and the friction piece having a main friction body extending between said first axial end and a second axial end, with an outer friction surface at the first and axial ends, and an actuated part there between, - Generating heat locally at the first interface, wherein heat is generated by one of a rotation between the friction piece and the socket part, or vibrations of the friction piece relative to the first socket part, thereby causing welding of friction piece and of the first socket part along the first interface

2. The method of claim 1, further comprising inserting a second axial end of the friction piece opposite the first axial end into the second socket part along a second interface, generating heat locally at the second interface, wherein heat is generated by one of a | 20 rotation of the friction piece, a rotation of the friction piece or vibrations of the friction piece, thereby causing welding of the along the second interface, wherein heat is generated simultaneously at the first interface and at the second interface.

3. Method of coupling a first socket part to a second socket part comprising the steps of - Inserting the first socket part into the second socket part along a first interface, wherein the second socket part is provided with a friction piece with main friction body having an inner friction surface extending along the first interface, at the first and axial ends, and a friction actuated part on an outer surface of the socket part, - Generating heat locally at the first interface, wherein heat is generated by one of a rotation between the friction piece and the socket part, or vibrations of the friction 3 juillet 2018

SONNENBERG soo0 I ARTMANN 13 piece relative to the first socket part, thereby causing welding of friction piece and_U100866 of the first socket part along the first interface

4. The method of any of claims 1 to 3, wherein heat is generated by rotation of the friction piece or by vibration of the friction piece, the method comprising applying pressure, by a clamping tool, on the first socket part, to prevent movement of the first socket part during heat generation.

5. The method of any of claims 1 to 4, wherein heat is generated by rotation of the first socket part, the method comprising applying pressure, by a clamping tool, on the friction body of the friction piece, to prevent movement of the friction piece during heat generation.

6. The method of any of claims 1 to 5, wherein heat is generated by rotation of the friction piece at alternate high frequency small rotations.

7. The method of any of claims 1 to 6, comprising measuring a torque applied on the friction piece and/or on the first socket part during relative rotation of the friction piece relative to the first socket part.

8. The method of any of the preceding claims, comprising providing at least one of a first bonding material on an outer surface of the friction piece, a second material on an inner surface of the first socket part and a third material on an inner surface of the second socket part, wherein the first bonding material, second material, and third bonding material comprises a transition polymer (hot melt).

9. Friction piece usable in a method according to claims 1 to 8, wherein the friction piece has a friction body with a first axial end and a second axial end opposite the first axial end, the friction body comprises a friction actuated part on its outer surface for rotation or vibration to the friction piece through a friction tool.

10. Friction piece according to claim 9, wherein the first axial end and/or the second axial end has a conical shape along the main axis, in particular wherein an inner diameter of the friction body is greater at the center of the friction body than at the first axial end or at the second axial end. 3 juillet 2018

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F27509LU FORTAN 14

11. Tool usable in a method according to claim 1, the tool comprising LU100866 a first jaw for clamping the first socket part on the first socket part along a first interface, an actuating part for actuating the remaining one of the first socket part or the friction piece, wherein the actuating part is configured to rotate the friction piece about said main axis or to rotate the first socket part along said main axis

12. The tool according to claim 11, the tool comprising a pressure applying part for applying pressure on the first socket part or the friction piece along the first interface, to increase the friction between the first socket part and the friction piece

13. The tool according to any of claims 11 to 12, comprising a torque sensor adapted to detect a torque applied by the actuating part on either one of the socket part or friction piece during rotation of the socket part or friction piece.

14. The tool according to any of claims 11 to 13, wherein the actuating part is a vibration actuating part, configured to rotate the friction piece at alternate high frequency small rotations.

3 juillet 2018