WO2017081258A1

WO2017081258A1 - Inducing a gelation and/or phase transition or a chemical change of state in a sealant to be applied

Info

Publication number: WO2017081258A1
Application number: PCT/EP2016/077442
Authority: WO
Inventors: Johann Resch; Martin ACHTER
Original assignee: Polyplan-GmbH Polyurethan-Maschinen
Priority date: 2015-11-11
Filing date: 2016-11-11
Publication date: 2017-05-18
Also published as: EP3374094A1

Abstract

The invention relates to a method for applying a sealant, particularly a wax blend, onto a body component or into a cavity of a vehicle, using a sealant applicator, particularly a wax applicator lance, wherein said sealant is conveyed in the liquid state by a conveyor device through the sealant applicator, and gelation and/or a phase transition or a chemical change of state is induced, gelation being induced within the sealant by virtue of the sealant being irradiated with electromagnetic radiation and particularly with UV light, immediately before, during, or immediately after application onto the body component, in order to induce a change of state using the electromagnetic radiation and to convert the sealant into a solid, particularly a gel-like and/or molecularly-crosslinked state.

Description

Inducing a gelling and / or a phase transition or a chemical change in state in a sealing substance to be applied

description

The invention relates to a method for applying a sealing substance, in particular a wax mixture on a body component or in a cavity of a vehicle by means of a sealing substance applicator, in particular a wax applicator lance, wherein the sealing substance from a conveyor in the liquid state through the

A sealant and / or a phase transition or a chemical change of state is induced according to the features of claim 1. Furthermore, an arrangement for applying a sealing substance, in particular a wax mixture on a body component or in a cavity of a vehicle with the features of claim 8 indicated.

The automotive industry has been applying for some time now

Sealant on body components or in cavities of a

Vehicle integrated in the manufacturing process to a seal

corrosion sensitive areas, such as folding, cavities, holes, etc. to effect. Conventionally, there has been a problem that the applied sealing substance could not be fixed by baking in a furnace until relatively late after application. As a result, there was a problem that the applied sealing substance was particularly liable to gravitational force, and thus, a sufficient sealing coat was no longer ensured at the site to be sealed with the sealing substance. Moreover, the provision of a furnace is disadvantageous from several points of view. There are significant installation costs and high energy because of the required energy

Operating costs. In addition, the production process is delayed by the necessary furnace time.

The object of the present invention is to specify a method and an arrangement with which a sealing substance can be applied to a body component of a vehicle and fixed there at the same time. This object is achieved in procedural terms with the features of claim 1 and in device-technical terms with the features of claim 11. Advantageous developments are specified in the subclaims.

A key consideration of the present invention is to effectuate the gelling within the sealant by causing the sealant to be applied to the body component or cavity immediately prior to application or immediately after application

Electromagnetic radiation is irradiated, in particular with UV light, to induce a change in state by the electromagnetic radiation and to convert the sealing substance in a firmer, in particular gel and / or molecularly crosslinked state. As already mentioned, the electromagnetic radiation can be in the UV range or even shorter wavelength. However, it is also possible to use micro or radio waves or even visible light. The irradiation can be continuous, intermittent or pulsed. It can be used relatively broadband or even radiation with a very narrow spectrum. As light sources, in addition to UV lamps or stroboscopic lamps and laser, in particular semiconductor or diode lasers, into consideration.

It is pointed out at this point that instead of the electromagnetic radiation for inducing a change in state and for transferring the sealing substance into a more solid, in particular gel and / or molecularly crosslinked state, alternatively or additionally, the use of other high-energy radiation into consideration and insofar the Electromagnetic radiation replaced by other high-energy radiation or both types of radiation can be applied combined.

In a first preferred embodiment of the method according to the invention, the transfer of the sealing substance from the liquid state to a more solid, in particular gel, state takes place within a process time t _P between 10 minutes and 10 seconds, preferably between 2 minutes and 30 seconds. Due to these relatively short process times, it is sufficiently ensured that bleeding of the sealing substance, in particular under the action of the sealing substance

Gravity no longer or no longer takes place to any appreciable extent. In a development of the method according to the invention, after the gelling of the sealing substance, a hardening process may take place, in which the sealing substance hardens.

A separation between gelling and final curing may be desired in the production process, since an immediate curing in the curing process itself or in the further production of the vehicle could lead to fractures and thus to an insufficiently effective seal.

It may be provided that the curing process is used automatically, at the latest after the start of gelling, possibly with a time delay, or that the curing process is also induced separately.

In an advantageous development of the method, the curing process compared to the process of transferring the sealing substance from a liquid state to a gel state (process of gelling) is set so that it takes much longer, preferably at least twice as long, more preferably at least 10th times it takes so long. On the one hand, this reciprocal adjustment of the processes of gelling on the one hand and hardening on the other hand ensures that the sealing substance is sufficiently fixed and, in particular, sagging under the action of gravity is prevented, but at the same time the sealing coating is still sufficiently flexible to allow further processing of the vehicle during assembly - not to impair process or survive without damage or even breaks.

In one possible embodiment, the final curing process is applied for a few hours to a few days.

In general, the duration of the gelling process can be defined by changing the fluidity of the material. In this case, the flowability of the sealing substance during application, before inducing gelling, may have a first value V, and after passing through the gelling process, a second value V _g . It can be considered as the start of the gelation process, as soon as the flowability of V, on V _g has reduced by at least 2% and as the end of the gelling process, as soon as 98% of the value V _{g are} reached. In the curing process, the start can be considered as the beginning of a cure and the end of the cure process when 80% of a final hardness (eg to Shore) is reached.

It may be provided in an advantageous development that an additional Induierungierung the gelling or Induzierung a curing takes place in that the sealing substance is heated before or during application to an application temperature T _A above an activation threshold T _s . The activation of a wax mixture by a so-called Heizkick is known per se. According to the present method, however, activation of at least one gelling, possibly also of the curing process, is induced by irradiation with electromagnetic radiation. Only additionally could gelling be supported by heating the sealing substance above an activation threshold T _s . At the same time, the activation of the curing process could be initiated by the heating of the sealing substance above the activation threshold T _s .

Furthermore, it is conceivable to additionally induce the gelling or to induce a hardening of the sealing substance before, during or after application to the body component or in a cavity by substances in the ambient air, such as oxygen, moisture or by another process-fed component.

In an optional embodiment of the proposed method, the sealing substance may be chosen such that the activation threshold T _{s is} in the range between 60 ° C and 120 ° C, preferably at about 80 ° C. The sealant may be ejected from the sealant applicator at a deployment temperature T _A of 90 ° C to 120 ° C, preferably about 95 ° C.

According to a central idea of the application according to the invention, it is provided that the means for inducing gelation or a

Phase transition or a chemical change in state in the

Sealing substance are provided from a liquid phase to a firmer, in particular gel, phase, wherein the means for inducing gelling comprise one or more irradiation means to the

Sealant to be irradiated immediately before, during or after impact with the body component and to induce gelling. It is explicitly pointed out that the means for inducing gelling can also induce curing at the same time, if the

Sealant is set and formed accordingly.

In one possible development, the means for inducing gelling or curing may also include heating means in the sealant applicator or upstream of the sealant applicator to heat the sealant and expel it at an application temperature T _A from the sealant applicator such that the sealing substance is kept liquid when ejected by the sealing substance applying means and gels after impacting the body member. In this variant, it may be useful to control the gelation of the sealing substance after hitting the body component also by the

Body component is maintained at a predetermined temperature or is heated to a predetermined temperature.

If UV light is used for the irradiation, radiation hardening takes place, for example, in such a way that a chemical change in state is produced with the aid of the high-energy radiation provided by the UV light. In example, reactive materials can be converted from a low molecular weight to a high molecular weight state by the high-energy radiation provided by the UV light.

The heaters may be provided upstream of the sealant application device. It is also conceivable that the heating devices heat the sealing substance over a prolonged period of time such that when it is expelled from the sealing application device

Application temperature T _{A is} guaranteed. As an alternative, it is also possible, in the manner of a continuous flow heater in the sealing substance application device or upstream of the sealing substance application device, to heat only the conveyed portion of the volumes of sealing substance to be discharged directly. If heating takes place directly in the sealant application device, heat losses during transport or storage are minimized. However, it is also conceivable to keep the heating process in two stages, for example, to heat the sealing substance in a storage container to a storage temperature T _v , which above the ambient temperature, z. B. at 50 ° C and only the remaining heating immediately before the ejection of the sealing substance in

To make a pass.

The invention will be explained below with regard to further features and advantages with reference to the description of exemplary embodiments and with reference to the following drawings:

Hereby show:

1 shows a first embodiment of an inventive arrangement for carrying out a variant of the method according to the invention;

Figure 2 shows a modified embodiment of an arrangement according to the

Invention for carrying out another variant of the method according to the invention; and

Figure 3 shows a further modified embodiment of an arrangement according to the invention for carrying out a further variant of the method according to the invention.

FIG. 1 illustrates a first embodiment of an arrangement according to the invention for carrying out a variant of the method according to the invention. In a storage container 15, a wax mixture is stored. The storage container 15 is in fluid communication with a delivery device 12, an interruption valve 16, and a sealant application device 11. The sealing substance accommodated in the storage container 15 can thus be ejected via the wax delivery device 12, the interruption valve 16 and the sealing substance application device 11 in the direction of a body component or into a cavity of a vehicle.

A control device 18 is in operative connection with the delivery device 12, the optionally provided interruption valve 16 and a UV irradiation device 14. Immediately upon ejection of the wax mixture from the sealant application device 11 or shortly after impact of the wax mixture on the body component, it is irradiated with UV light to to convert the wax mixture from a liquid to a firmer state, in particular by a chemical change of state. By the high-energy radiation of UV light, for example, low molecular weight components can be converted into high molecular weight components and thus a stronger crosslinking or solidification of the wax mixture can be achieved.

Irradiation with UV light can be continuous, intermittent or pulsed.

FIG. 2 illustrates a modified embodiment of an arrangement according to the invention for carrying out another variant of the method according to the invention. Here, the sealing substance stockpiled in the storage container 15 is heated by a heater 13 on a first

Temperature level above room temperature of z. B. 90 ° C held. Furthermore, between the optionally provided interruption valve 16 and the

Sealing substance application device 11, a second heater 17 is provided to the concretely conveyed via the conveyor 12 and ejected from the sealing substance application device 11

Sealant on the principle of the water heater on a

Application temperature T _A, for example, 105 ° C to heat. In this respect, in this embodiment, heated sealing substance on a

Applied body component or in a cavity of a vehicle and induced by the UV irradiation device 14, the gelling. Possibly. In addition, the gelation can also be supported by the heating, wherein the

Sealant is heated to an application temperature T _A above the activation threshold T _s . The activation threshold can

for example, be at 100 ° C.

A hardening process of the sealing substance can be achieved either by the

Heating over the activation threshold T _s or via the irradiation with electromagnetic radiation, in particular by irradiation with UV light initiated.

FIG. 3 illustrates a further modified embodiment of an arrangement according to the invention for carrying out a further variant of the method according to the invention. In a storage container 15, a sealing substance is stored, the analogous to the arrangements or process variants according to Figures 1 or 2 via a conveyor 12 and an optionally provided interruption valve 16 is conveyed to a sealing substance application device 11. Furthermore, a Hilfsstoffausstoßeinrichtung 19 is provided, which is kept ready in a Hilfsstoffbevorratungsbehälter 20 and conveyed via an auxiliary material conveyor 21 and an optional auxiliary material interruption valve 22 to the aforementioned auxiliary ejector 19. Both the discharge of the wax mixture from the sealant substance delivery device 11 and the discharge of the excipient via the excipient discharge device 19 can be controlled via a control device 18, either by controlling the performance of the delivery device 12 or of the auxiliary substance delivery device 21 and / or by appropriate actuation of the interruption valve 16 or the auxiliary substance interruption valve 22.

Via the excipient ejected via the auxiliary substance ejection device 19, the induction of gelling can be assisted or the curing of the

Sealant induced or supported.

LIST OF REFERENCE NUMBERS

11 Sealing application device

12 conveyor

13 heating device

14 UV irradiation device

15 storage container

16 break valve

17 (second) heater

18 control device

19 auxiliary ejector

20 auxiliary storage containers

21 auxiliary material conveyor

22 auxiliary stop valve

T _A application temperature

Ts activation threshold

t _P process time

Claims

claims

Method for applying a sealing substance, in particular a wax mixture, to a body component or cavity of a vehicle by means of a sealing substance application device (11), in particular a wax application lance, the sealing substance being conveyed by a conveying device (12) in the liquid state through the sealing substance application device (11 ) and gelling and / or a phase transition or a chemical change of state is induced, whereby the gelling is induced within the sealing substance by applying the sealing substance immediately before, during application or immediately after application to the body component with electromagnetic radiation, in particular with UV light is irradiated in order to induce a change in state by the electromagnetic radiation and the sealing substance in a firmer, in particular gel and / or molecular verne to transform the damaged state.

2. The method according to claim 1,

It does not mean that

the transfer of the sealing substance from the liquid state to a firmer, in particular gel state, takes place within a process time t _p between 10 min and 10 s, preferably between 2 min and 30 s.

3. The method according to any one of claims 1 or 2,

It does not mean that

after the gelling of the sealing substance, a hardening process follows, in which the sealing substance hardens.

4. The method according to claim 3,

It does not mean that

the curing process automatically at the latest after the beginning of the Gelling may be delayed, or that the curing process is induced separately.

5. The method according to claim 3 or 4,

It does not mean that

the curing process is carried out in comparison to the transfer of the sealing substance from a liquid state to a gel state, preferably for at least a double, more preferably at least 10 times as long duration.

6. The method according to any one of claims 3 to 4,

It does not mean that

the curing process takes between a few hours to a few days.

7. The method according to claim 1,

It does not mean that

an additional inducing of the gelling or an induction of hardening takes place in that the sealing substance is heated to an application temperature T _A above an activation threshold T _s before or during application.

8. The method according to any one of claims 1 or 2,

It does not mean that

additionally inducing gelling or inducing hardening of the sealing substance before, during or after

Applying to the body component or in a cavity by substances in the ambient air, such as oxygen, moisture or by another process supplied component takes place.

9. The method according to any one of claims 7 or 8,

There is no sign that

the sealing substance is chosen so that the activation threshold T _{s is} in the range between 60 ° C and 120 ° C, preferably at about 80 ° C.

10. The method according to any one of claims 1 to 9,

It does not mean that

the sealing substance with a discharge temperature T _A of 90 ° C to 120 ° C, preferably from about 95 ° C from the Dichtungsausausungs- device (11) is ejected.

11. Arrangement for applying a sealing substance, in particular a wax mixture, to a body component or in a cavity of a vehicle, in particular for carrying out the method according to claims 1 to 10, comprising:

a sealing applicator (11),

a conveying device (12) for conveying the sealing substance through the sealing substance application device (11), which indicates that

Means (13/14) are provided for inducing a gellation or a phase change or a chemical change of state in the sealing substance from a liquid phase to a firmer, in particular gel phase, wherein the means for

Inducing gelling, comprising one or more irradiation means (14) for irradiating the wax mixture with electromagnetic radiation, in particular UV light, immediately before, during or after striking the body component, and inducing gelling.

12. Arrangement according to claim 11,

It does not mean that

the means for inducing gelling or curing comprise heating means (13) in the sealing substance applying means or upstream of the sealing substance applying means (11) for heating the sealing substance and discharging it from the sealing substance applying means (11) at an application temperature T _A so that the sealing substance is kept liquid on ejection by the sealing substance applying means (11) and gels upon striking the body member.

13. Arrangement according to claim 11 or 12,

It does not mean that

the irradiation devices (14) are arranged or integrated in or on the wax application lance.