Open Time Compensated Gluing Process and Gluing Apparatus

Abstract

In a manufacturing method of a laminate structure according to the invention, a manufacturing apparatus of the laminate structure is used, which apparatus comprises material containers for the glue paste components, a separate pump for each glue paste component, which pumps are arranged to pump the components of the glue paste to be manufactured through the outlet pipes to the mixing unit. Furthermore, the glue paste manufacturing apparatus comprises a control unit of the glue manufacturing apparatus, which control unit is arranged to determine the mutual mixing ratio of the glue components at the starting moment of the glue manufacturing process, to start the pumping of the different glue components in connection with the starting of the mixing unit, to pump the glue components with component-specific pumps to the mixing unit in a mixture ratio determined by the control unit, and that the control unit is arranged to adjust the ratio of the glue components as a function of time so that the open time of the glue coming out from the mixing unit shortens towards the end of the gluing process, whereby the clamping time of the elements of the laminate to be glued together shortens so as to be as long as the clamping time of the glue layer having the shortest open time, upon the expiry of which all the glue layers of the laminate structure have reached the target hardness.

Claims

1. A gluing method for gluing part elements of a laminate structure, in which method: at least two glue components and a hardener to be used in the gluing of the part elements are selected at a control unit of a glue manufacturing apparatus, the control unit of the glue manufacturing apparatus determines a mutual mixing ratio of selected glue components at a starting moment of glue manufacturing process, pumping of different glue components to a mixing unit is started after the determination of the mixing ratio, the glue components are pumped to the mixing unit with component-specific pumps in a mixture ratio determined by the control unit, wherein, the selected glue components have open times of different lengths and the control unit adjusts the mixing ratio of the glue components to be administered on a part element as a function of time so that the open time of the glue coming out from the mixing unit shortens after each part element fastened to the laminate structure towards end of gluing process, whereby a clamping time of the part elements of the laminate structure to be glued together is as long as a clamping time of last administered glue layer having the shortest open time, upon expiry of which all glue layers have reached a target hardness.

2. (canceled)

3. The gluing method according to claim 1, wherein the determination of the mutual mixing ratio of the glue components at the starting moment of the process, the temperature of the production area used in the gluing is measured and the reaction rate curves of the different mixture ratios in the measured temperature are taken into consideration in the determination.

4. The gluing method according to claim 3, wherein the temperature rise of the production area is compensated by increasing the proportion of the glue component having the longest open time in the finished glue mixture and that the temperature drop of the production area is compensated by increasing the proportion of the glue component having the shortest open time in the finished glue mixture.

5. The gluing method according to claim 1, wherein the mixing ratio of the glue components is continuously changed so that the proportion of the glue component having the shortest open time is increased with continuous control until the end of the glue manufacturing process of the elements to be glued together.

6. The gluing method according to claim 1, wherein the mixing ratio of the glue components is changed stepwise when starting the manufacture of a new glue layer on the part element fastened last onto the laminate.

7. The gluing method according to claim 1, wherein the glue components are either polyurethane- or epoxy-based components.

8. A manufacturing arrangement of a laminate structure comprised of part elements, which arrangement comprises a glue manufacturing apparatus, comprising: material containers for glue components, a separate pump for each glue component, which pumps are arranged to pump the components of the glue to be manufactured through outlet pipes to a mixing unit, a control unit of the glue manufacturing apparatus, which control unit is arranged: to determine a mutual mixing ratio of the glue components at a starting moment of glue manufacturing process, to start pumping of the different glue components in connection with starting of the mixing unit, to pump the glue components to the mixing unit with component-specific pumps in a mixture ratio determined by the control unit, wherein, the selected glue components have open times of different lengths and the control unit is arranged to control the ratio of the components of the glue to be administered on a part element as a function of time, so that the open time of the glue coming out from the mixing unit shortens after every part element fastened to the laminate structure towards the end of the gluing process, whereby the clamping time of the part elements to be glued together of the laminate to be manufactured is as long as the clamping time of the last administered glue layer having the shortest open time, upon the expiry of which time all the glue layers have reached the target hardness.

9. (canceled)

10. The manufacturing arrangement of a laminate structure comprised of part elements according to claim 8, wherein in the manufacturing apparatus, the temperature of the production area to be used in the gluing is arranged to be measured, which temperature is arranged to be taken into consideration in the determination of the mutual mixing ratio of the glue components at the starting moment of the glue manufacturing process and that the reaction rate curves of the different mixture ratios in the measured temperature are arranged to be taken into consideration in the determination.

11. The manufacturing arrangement of a laminate structure comprised of part elements according to claim 10, wherein in the manufacturing apparatus, the temperature rise of the production area is arranged to be compensated by increasing the proportion of the glue component having the longest open time in the finished glue mixture and that the temperature drop of the production area is arranged to be compensated by increasing the proportion of the glue component having the shortest open time in the finished glue mixture.

12. The manufacturing arrangement of a laminate structure comprised of part elements according to claim 8, wherein the mixing ratio of the glue components is arranged to be continuously changed, so that the proportion of the glue component having the shorter open time is increased with continuous control until the end of the glue manufacturing process.

13. The manufacturing arrangement of a laminate structure comprised of part elements according to claim 8, wherein the mixing ratio of the glue components is arranged to be changed stepwise when starting the glue manufacture on the part element last glued to the laminate.

14. The manufacturing arrangement of a laminate structure comprised of part elements according to claim 8 wherein the used glue components are either polyurethane- or epoxy-based components.

15. A computer program product, which comprises computer program code means stored on a computer-readable storage medium, which code means, when said computer program product is run on a computer, are arranged to select the at least two glue components and a hardener of the glue to be used in gluing of the laminate structure, to determine a mutual mixing ratio of the selected glue components at a starting moment of the glue manufacturing process, to start pumping of the different glue components to a mixing unit after the determination of the mixing ratio, wherein, in the computer program product further comprises code means, which are for gluing part elements of a laminate structure arranged to select the glue components having open times of different lengths and to control the mixing ratio of the glue components as a function of time so that the open time of the glue coming out from the mixing unit shortens after every part element fastened to the laminate structure towards the end of the gluing process, whereby the clamping time of the part elements to be glued together of the laminate structure to be manufactured is as long as the clamping time of the last glue layer having the shortest open time, upon the expiry of which time all the glue layers have reached the target hardness.

Description

[0026] In the following, the invention will be described in detail. In the description, reference is made to the enclosed drawings, in which

[0027] FIG. 1 shows by way of an example glue layers manufactured for the gluing of two part elements together according to the prior art and the total time required by the gluing,

[0028] FIG. 2 shows by way of an example a glue paste manufacturing apparatus according to the invention,

[0029] FIG. 3 shows by way of an example glue layers manufactured for the gluing of two part elements together according to the prior art and the total time required by the gluing, and

[0030] FIG. 4 shows as an exemplary flow chart the main stages of the glue manufacturing method according to the invention.

[0031] The embodiments in the following description are only exemplary and a person skilled in the art can carry out the basic idea of the invention also in some other way than what is described in the description. Even though it may be referred to an embodiment or embodiments in several places of the description, this does not mean that the reference would be directed to only one described embodiment or that the described characteristic would be usable only in one described embodiment. The individual characteristics of two or more embodiments may be combined and new embodiments of the invention may thus be provided.

[0032] FIG. 1 is presented in connection with the description of the prior art.

[0033] FIG. 2 shows a glue paste manufacturing apparatus 100 according to the invention. The functions of the glue paste manufacturing apparatus 100 are controlled by a control unit 40. The control unit can preferably be for example a data processing device, a PC or a tablet, built up for the glue paste manufacturing apparatus 100. In all alternative embodiments the control unit 40 comprises a processor, memory units, a power source, a display and a user interface. The computer program to be utilized in the glue manufacturing method according to the invention is preferably stored in the memory unit of the control unit 40, from where the processor of the control unit 40 retrieves and performs the computer program commands to be utilized in the glue manufacturing method.

[0034] The glue needed in the gluing object 60 is mixed in the mixing unit 30 from two or more glue components to meet the requirements of the gluing object 60.

[0035] The first component of the glue to be used is in the material container 1, reference 10. Due to the properties of the glue to be manufactured, other components are mixed to the first component from at least one further material container 2, reference 11. The components can be for example a hardener and different kinds of filling agents.

[0036] Each material container 10-12 of the glue component is connected to its own pump through a feeding pipe. In the example of FIG. 2, the material container 10 is connected to the pump 1 through a feeding pipe 10a of the respective pump, reference 20. Respectively, the material container 11 is connected to the pump 2, reference 21, through a feeding pipe 11a and the material container 12 is connected to the pump N through a feeding pipe 12a of the respective pump, reference 22. The operation of the pumps 20-22 is controlled by the control unit 40, which belongs to the glue paste manufacturing apparatus 100, so that the first glue component from the container 10 and other components from the containers 11-12 are fed to the mixer 30 in a mixture ratio determined by the open time required by the gluing object 60.

[0037] Preferably, in the beginning of the glue manufacturing process, the open times of all glue components and also the ambient temperature in the gluing object are taken into consideration in the determination of the mixture ratio of the components. All these affect the open time to be generated for the glue mixture to be manufactured.

[0038] From each pump 20-22, an outlet pipe 20a, 21a and 22a of its own is connected to the inlet of the mixing unit 30. The operation principle of the mixing unit 30 can be selected according to the glue to be manufactured and/or according to the gluing object 60. The mixing unit 30 can be for example a contrarotary spiral mixer. The glue paste manufactured in the mixing unit 30 is guided through the outlet pipe 30a to the actual gluing object 60.

[0039] The operation of the glue paste manufacturing apparatus 100 is controlled by the control unit 40. The control unit 40 receives the ambient temperature information either trough a wireless or wire data transmission 51 from an electronic thermometer 50, which is near the gluing object 60. In a preferred embodiment of the invention the thermometer measures the surface temperature of the part elements to be glued together of the laminate to be manufactured at the starting moment of the gluing. The open time scheduled for the gluing object 60 can be preferably entered through the user interface, which belongs to the control unit 30.

[0040] On the basis of the measured ambient temperature or the surface temperature of the part elements to be glued, on the basis of the reaction rate curves measured for the different mixing ratios of the glue components and on the basis of the open time scheduled for the gluing object 60, the determination and control program of the glue mixing ratio installed in the control unit 40 determines the mixture ratio of the glue components, with which mixture ratio the glue manufacture is started in the mixing unit 30. Preferably, at the starting moment of the manufacture, 80% of the glue component having the longest open time is added to the glue mixture and the rest 20% can be of one or more glue components having a shorter open time.

[0041] The starting commands, which preferably comprise running speed determinations of the pumps 20, 21 and 22, by which the mixture ratio of the components of the glue to be manufactured is determined, are sent by the control unit 40 through the connections 40a, 40b and 40n. The operation and mode of the mixing unit 30 are controlled and monitored by the control unit 40 through the connections 41 and 42.

[0042] In the glue manufacturing apparatus 100 according to the invention, the mixture ratio of the components of the glue to be manufactured is continuously changed during the glue manufacture. The ambient temperature data stored in the control unit 40 and the open time of the glue mixture set as a target are utilized by the control unit 40 when changing the mixture ratio of the components of the glue mixture so that when the glue layers of the last two part elements of the laminate are finished, 80% of the glue mixture is of the glue component having the shortest open time and 20% is of the glue component having the longest open time.

[0043] The control unit 30 preferably continuously (steplessly) changes the mixture ratio of the glue to be manufactured from the starting mixture ratio towards the end mixture ratio.

[0044] In a preferred embodiment of the invention, the mixture ratios of the glue to be manufactured are preferably changed stepwise when a new glue layer is spread on the existing already glued part element in the gluing object 60. Also in this embodiment, the lowest (the first) glue layer has the longest open time and the uppermost (the last) glue layer between the two uppermost part elements of the laminate has the shortest open time.

[0045] When using both manufacturing methods according to the invention, the clamping time needed for one gluing is approximately shortened by 50% compared to the gluing according to the prior art (FIG. 1), in which glue, the open time of which is not changed during the gluing process, is used.

[0046] FIG. 3 shows as an exemplary schematic representation, how the manufacturing method according to the invention substantially shortens the time needed for the gluing compared to a gluing situation similar to the example of FIG. 1. The open times and the mixture ratios of the different glue components in the beginning and at the end of the gluing shown in FIG. 3 are only exemplary. The lowest, the intermediate and the uppermost part elements of the laminate of the glue layers 1-5 are not shown in FIG. 3.

[0047] In the example of FIG. 3, the glue is mixed from the two glue components A and B (the glue hardener is not shown in the Figure). The glue component has an open time of 15 minutes and a substantially equally long clamping time. The second glue component B has an open time of 30 minutes and a substantially equally long clamping time. It is obvious for the person skilled in the art that it is possible to apply the invention also with other kinds of mixture ratios depending on the purpose of use. When the glue manufacture in the example of FIG. 3 is started, the mixture ratio of the glue components A/B in the glue is 20/80%. Thus, the open time of the glue is slightly shorter than the open time of 30 minutes of the component B.

[0048] When the gluing progresses from the layer number 1, which is the glue layer between the two lowest part elements of the laminate to be manufactured to the layer number 5, with which the uppermost part element of the laminate is glued to the laminate, the mixture ratio A/B of the glue is changed so that in the glue manufacture, when the need of glue for the gluing object 60 ends in point Y, the mixture ratio A/B of the glue is 80/20%. In that case, the open time of the glue is slightly longer than the open time of 15 minutes of the component B. In point Y, also the last glue layer has been spread, whereby the clamping of the elements can be started. In the beginning of the clamping, the last spread glue layers are still in the open time mode, wherein the start of the clamping stage is possible after 30 minutes. In about 60 minutes from the start of the gluing process all the glue layers 1-5 between the part elements of the laminate have hardened substantially equally hard, wherein the laminate to be glued can be removed from the clamping device.

[0049] Depending on the purpose of application (how hard the glue must be hardened) the necessary clamping time can be either shorter or longer than what can be calculated from the open time alone.

[0050] In the first preferred embodiment of the invention the mixture ratio A/B of the glue components is continuously changed as a function of time from the mixture ratio of 20/80% of the starting situation to a mixture ratio of 80/20%. By acting this way, the clamping time of the last glue layer and the clamping time required by the lowest layer substantially expire at the same time in about 60 minutes from the start of the gluing in the gluing object 60. In this case, the hardness of the glue layers 1-5 between all part elements of the laminate to be manufactured is of the same hardness category, wherein the clamping can be stopped. With the gluing method and the gluing apparatus 100 according to the invention, by shortening the clamping time, a time saving of about 30% compared to the gluing time needed with a manufacturing technique according to the prior art of FIG. 1, is thus achieved.

[0051] In another preferred embodiment of the invention the mixture ratio NB of the glue components is changed stepwise when a new glue layer is laminated on the already existing glue layer in the gluing object 60.

[0052] FIG. 4 shows as an exemplary flow chart the main stages of the gluing method according to the invention. In connection with the description of the method, it is referred to the example shown in FIG. 3 and to the glue components A and B used therein. However, the invention is not only limited to the components A and B according to FIG. 3 or to their exemplary mixture ratios in FIG. 3.

[0053] In stage 300, the glue manufacture is started.

[0054] In stage 340, the pumps 20-22 of the glue components and the mixing unit 30 are started, whereby the glue manufacture starts.

[0055] In stage 310, the control unit 40 of the glue paste manufacturing apparatus 100 stores the temperature measured by the thermometer 50 in the gluing object 60 in its memory.

[0056] In stage 320, the different glue components A and B are selected. The selection can either be based on the choices made by the person operating the glue manufacturing apparatus or the selection can, in some cases, be made by the control unit 40 of the glue manufacturing apparatus 100 with an artificial intelligence software stored therein.

[0057] In stage 330, the control unit 40 determines the mixture ratio of the glue components A/B at the starting moment of the glue manufacture. The determination of the mixture ratio is based on the selected glue components A and B, on the measured ambient temperature and on the target-oriented time needed for the gluing, which time is calculated from the open times and clamping times needed with different mixture ratios of the glue components A/B. Also the reaction rate curves measured experimentally with the mixture ratios of the different components in different temperatures can be preferably utilized in the determination of the starting mixture ratio.

[0058] In stage 340, the control unit 40 of the glue paste manufacturing apparatus 100 sends the starting commands to the mixing unit 30 and to the pumps 20-22. The starting commands of the pumps include standard values for such rotation speeds, that the mixture ratio A/B of the glue of the starting situation corresponds to the mixture ratio determination made in stage 330, for example the mixture ratio A/B of 20/80% of FIG. 3.

[0059] In stage 350, the pumps 20-22 of the glue paste manufacturing apparatus 100 pump the different glue components in a mixture ratio A/B determined by the control unit 40, each with its own outlet pipe 20a, 21a and 22a to the inlet connectors 30 of the mixer. The pumps 20-22 suck the glue components A and B from the material containers 10-12 through the pump-specific feeding pipes 10a-12a.

[0060] In stage 360, the glue mixing unit 30 and the pumps 20-22 are in operation. The control unit 40 of the glue paste manufacturing apparatus 100 continuously economizes the rotation rate of the pumps 20-22 so that the mixture ratio of the glue components A/B changes so that the open time of the glue mixture shortens as a function of time towards the open time of the glue component B having the shortest open time. The glue received from the mixing unit 30 is spread during the stage 360 as one or more glue layers on the surface of at least one element to be glued.

[0061] In stage 370, it is stated that all the glue layers necessary for the manufacture of the laminate between the different part elements of the laminate are finished (point Y in FIG. 3), thus, the manufacturing process of the glue is interrupted.

[0062] In stage 380, the elements to be glued together are clamped against each other. The clamping stage lasts about 30 minutes with the values of the open time and of the clamping time of the glue components A and B having the open time and clamping time according to the example of FIG. 3.

[0063] In stage 390, the elements are glued together.

[0064] The process steps describing the gluing process shown in FIG. 4 can be accomplished with computer program commands, which are performed in an appropriate universal processor or in a special processor, which is a part of the control unit 40 of the glue paste manufacturing apparatus 100. The computer program commands can be stored in a computer-readable media, such as a data disk or a memory of the control unit 40, from where the processor of the control unit 40 can retrieve said computer program commands and implement them. The references to the computer-readable media can for example also contain special components, such as programmable USB Flash memories, logic arrays (FPLA), application-specific integrated circuits (ASIC) and signal processors (DSP).

[0065] Some advantageous embodiments of the gluing method and the manufacturing apparatus arrangement of the laminate structure according to the invention have been described above. The invention is not limited to the solutions described above, but the inventive idea can be applied in numerous ways within the scope of the claims.