Producing a profile strand

Abstract

In order to achieve high product quality and process reliability in a process for manufacturing an endless profile strand of soft plastic and/or rubber material fed to a supply storage for a sealing profile, edge protection profile or the like on a motor vehicle, it is provided that the manufacturing process be divided into two process sections which are carried out on two manufacturing lines that can be operated independently of one another.

Claims

1. A method for processing a profile strand, comprising: feeding the profile strand to an intermediate storage during a first process section; removing the profile strand from the intermediate storage during a second process section that is downstream of the first process section; and then feeding the profile strand to a supply storage; wherein the second process section includes cutting one or more defects out of the profile strand, and then one or both of (a) rejoining ends of the profile strand created by cutting out the one or more defects to form one or more joints, or (b) applying an adhesive strip to the profile strand over ends of the profile strand created by cutting out the one or more defects to form the one or more joints, and wherein a temperature of the profile strand when the profile strand is removed from the intermediate storage at the beginning of the second process section is at least 50% lower than a temperature of the profile strand at which the profile strand is fed to the intermediate storage at the end of the first process section.

2. The method of claim 1, wherein the second process section performed on a second manufacturing line is performed temporally downstream of the first process section and independently of the first process section.

3. The method of claim 1, wherein the profile strand is fed to the intermediate storage before cutting out the defects or applying the adhesive strip.

4. The method of claim 1, further comprising, during the first process section, marking the one or more defects with defect markings on the profile strand, and in the second process section, identifying the one or more defects marked in the first process section by a detection device on the basis of the defect markings made in the first process section.

5. The method of claim 4, further comprising, in the second process section, separating the one or more defects identified by the detecting device out of the profile strand with a separating device, and rejoining ends of the profile strand created by cutting out the one or more defects with a joining device to form the one or more joints.

6. The method of claim 1, wherein at least twenty-four hours elapse between carrying out the first process section and carrying out the second process section with the intermediate storage.

7. The method of claim 1, wherein, in the second process section, one of the ends of the profile strand created by cutting out the one or more defects is a lagging end with respect to a feed direction, and the lagging end is fed in the feed direction to a joining device for subsequent joining one of the ends that is a leading end with respect to the feed direction for producing one of the one or more joints.

8. The method of method of claim 7, wherein, in the second process section, an adhesive strip station for applying an adhesive strip applies the adhesive strip without interruption over a previously created one of the one or more joints.

9. The method of claim 1, wherein the second process section further includes at least one of (a) monitoring to ensure a minimum distance L.sub.MIN between joints or (b) monitoring to ensure a length-related maximum number of joints Z.sub.MAX.

10. A method for processing a profile strand, comprising: feeding the profile strand to an intermediate storage during a first process section; removing the profile strand from the intermediate storage during a second process section that is downstream of the first process section; and then feeding the profile strand to a supply storage; wherein the second process section includes cutting one or more defects out of the profile strand, and then one or both of (a) rejoining ends of the profile strand created by cutting out the one or more defects to form one or more joints, or (b) applying an adhesive strip to the profile strand over ends of the profile strand created by cutting out the one or more defects to form the one or more joints, wherein, in the second process section, one of the ends of the profile strand created by cutting out the one or more defects is a lagging end with respect to a feed direction, and the lagging end is fed in the feed direction to a joining device for subsequent joining one of the ends that is a leading end with respect to the feed direction for producing one of the one or more joints, and wherein, in the second process section, an adhesive strip station applies the adhesive strip without interruption over a previously created one of the one or more joints.

Description

BRIEF SUMMARY OF THE DRAWINGS

(1) In the following drawings, the disclosure is described according to an exemplarily illustrated process control.

(2) The drawings show:

(3) FIG. 1: a profile strand in a perspective view looking at an end parting of a profile strand;

(4) FIG. 2: a profile strand having a joint and provided with an adhesive strip;

(5) FIG. 3: a first manufacturing line by performing a first process section; and

(6) FIGS. 4A-4F different states of a second manufacturing line for performing a second process section.

DESCRIPTION

(7) FIG. 1 shows an example of a profile strand 1 typically used as a door seal in a motor vehicle. The profile strand 1 is multi-component and has a first material region 2 made of a (soft) rubber or rubber material (e.g. EPDM) and a second material region 3 made of a soft (rubber) or rubber material (e.g. EPDM). The first material region 2 is highly flexible on the outside due to the material, which is preferably sponge rubber, and the tubular design of the hollow-chamber profile strand cross-section it forms, and is able to fit sealingly against the body portion with which it comes into contact when the door is closed. The second material area 3, which is somewhat stiffer than the first material area 2, forms a U-shaped receiving channel A. The profile strand 1 is attached to the motor vehicle via the second material area 3, in particular by means of an adhesive tape.

(8) The lower, free leg of the U-shaped receiving channel A in FIG. 1 has an adhesive strip 4 on its underside. As can be seen from the illustration in FIG. 2, the adhesive strip 4 has a multi-layer structure with an adhesive layer 5 and a liner 6, which is removed before the profile strand is applied to the body. As can be seen from FIG. 2, the adhesive strip 4 extends without interruption (without itself being interrupted) over a joint V which was created before application of the adhesive strip 4 by cutting out a defective area and rejoining the resulting separating ends. To join the separating ends, a jointing compound 8 was introduced into the joint, by means of which the separating ends were joined materially bonded.

(9) The section of the profile strand shown as an example in FIG. 1 and FIG. 2 can be part of an endless profile strand, such as can be produced by the method explained below.

(10) FIG. 3 shows a first manufacturing line 100 on which, starting from a starting material, typically a (soft) rubber (e.g. an EPDM rubber compound and/or another sponge rubber compound) in granular or strip form, an endless profile strand 110 is produced in a continuous process. The starting material is fed to an extruder 101, extruded, heated in multiple stages for through-vulcanization (microwaves 102), cooled (spray cooling 104), dried (drying 106), lacquered with release lacquer (release lacquering device 108) and dried again (lacquer drying 110). The result of this production section is an endless profile strand which has been vulcanized through and lacquered with release lacquer at a temperature which is high due to the process. The exact sequence of the measures described above and the number and arrangement of the devices required for this purpose are shown in FIG. 3 purely by way of example and for explanatory purposes only and are not the actual subject matter of the disclosure.

(11) Following the measures described above, the first manufacturing line 100 shown in FIG. 3 has an inspection device 120 for inspecting the profile strand for any defects. The inspection device 120 preferably comprises an optical, software-supported inspection system with a camera 122, which is capable of independently detecting unmarked defects 10, which are marked with an “x” in FIG. 3, on the basis of software-supported optical monitoring of the endless profile strand moving past the camera 122 in the feed direction S. The camera 122 is then used to check the continuous profile strand for defects 10. If a defect 10 is recognized as a defect to be separated out, it is marked by a marking device 124. Preferably, a colored marking is applied to the profile strand surface in the area of a defect or close in front of or close behind a defect, which marking is visually distinct from the typically black surface of the profile strand. The defect marked in this way becomes a marked defect 11, which is indicated by a “.circle-solid.” in FIG. 3 and FIG. 4.

(12) The first manufacturing line 100 may further comprise a first strand accumulator 130, which is capable of compensating for speed differences before and after the first strand accumulator 130 by varying the effective accumulator height H.sub.A1. In addition to the effective accumulator height, the line storage capacity of the accumulator is also determined by the number of upper and lower deflection rollers, which in practice are typically arranged on a common axis, unlike in the schematic diagram of FIG. 3. However, in the process according to the disclosure, due to the separation of the process into the two independent process sections shown in FIG. 3 and FIG. 4 and carried out on different manufacturing lines, a strand accumulator is not always necessary in the first process section, since the measures that make strand accumulation in a strand accumulator significantly necessary are preferably carried out in the second process section.

(13) At the end of the first process section, the endless profile strand produced in this process section is preferably fed to an intermediate storage 150 with marked defects that still have to be cut out and without adhesive strips applied. At this point, the profile strand has a high temperature due to the process. The intermediate storage is removed from the first manufacturing line and at a later time fed to the second manufacturing line 200, which is independent of the first manufacturing line 100 in terms of control technology, to carry out the second process section.

(14) FIG. 4 shows in FIG. 4A to FIG. 4F a total of six individual representations of various measures and process stages of the second process section carried out on the second manufacturing line 200, which, due to the separation of the first manufacturing line 100 and the second manufacturing line 200, can be carried out not only in terms of automated process control but also at a location and time separate from the first process section at the profile strand manufacturer.

(15) At the start of the second process section, an intermediate storage 150 filled in the first process section on the first manufacturing line 100 is first fed to the second manufacturing line 200 or the second process section. The profile strand located thereon is subsequently removed from the intermediate storage 150 and guided in the feed direction S past a detection device 210, such as a camera illustrated in FIG. 4A, which is capable of identifying the defect 11 detected and marked in the first process section on the basis of the marking applied in the first process section. The use of a marking applied in the first process section in the second process section has several advantages. In particular, a substantially simplified detection device 210 can be used, which, for example, only has to detect a large-area colored marking that is clearly distinguishable from the surface of the profile strand. Furthermore, such markings can also be seen with the naked eye by a system operator, who can verify the proper functioning of the system by following the color marking with the naked eye and can thus make a significant contribution to process reliability and product quality.

(16) A defect station 220 is provided at a defined distance L.sub.MIN from the detection device 210, through which the profile strand passes at a feed speed v.sub.220 adapted to the measures carried out in the defect station, which can also be temporarily zero. This defect station is followed by a control device, preferably in the form of a control rocker 240, by means of which it can be detected whether and to what extent the feed speeds differ along the manufacturing line and to what extent the profile strand to be wound onto the supply storage 250, the feed speed v.sub.260 of which should be kept as constant as possible when passing through an adhesive strip station 260 to ensure good adhesive strip application throughout the profile strand length, must be tracked from the strand accumulator 230. For this purpose, the strand section passing through the control rocker is loaded with the weight force F.sub.G via a weight 242, and the control rocker registers a lifting and or lowering of a deflection or urging upwards or downwards from a set position, which is to be attributed to any local speed differences, which then results in a reduction or increase of the instantaneous height H.sub.A2 of the strand accumulator 230, since the control system endeavors to keep the control rocker in the set position.

(17) At the end of the second process section, the finished endless profile strand is finally fed to the supply storage 250 to be delivered to the customer. Only this profile strand is free of defects due to the process and only has high quality joints. Furthermore, the profile strand fed to the supply storage has an adhesive strip extending uninterruptedly over a joint and therefore also imparts high structural integrity to the joint. In the following, some of the process steps indicated above are explained separately with reference to individual illustrations of FIGS. 4A-4F.

(18) In FIG. 4A, it can be seen that the defect detecting device 210 detects a marked defect 11′. This defect 11′ is continued to the separating device 222, which preferably has a distance L.sub.MIN from the defect detecting device. The defect 11′ is then separated from the profile strand by the separating device 222, as shown in FIG. 4B. The short strand section containing the defect 11′ can be disposed of. Since for the separation of the defect 11′ the profile strand section located in the area of the separating device 222 and the joining device 226 is temporarily stopped (temporary local feed speed v.sub.220=0), after the separating end resulting from the separation, which precedes the cut out profile strand section, has been continued in the direction of the joining device 226 (temporary local feed speed v.sub.220 briefly greater than but close to 0), but the profile strand section passing through the adhesive strip station 260 is preferably kept at a constant local feed speed (v.sub.260=constant), the two said local feed speeds v.sub.220 and v.sub.260 differ. The control rocker 240 registers the local slowing and stopping of the profile strand in front of the control rocker by urging the control rocker deflection upward. To compensate for the speed difference, the height H.sub.A2 of the strand accumulator 230 is reduced so that local feed speed V.sub.260 can be kept constant in the gluing strip station 260.

(19) In FIG. 4B it can then be seen that a further marked defect 11″ has already passed the defect detection device 210 before the defect 11′ has reached the separation device. This means that the second defect 11″ follows the leading defect 11′ at a distance which is less than the minimum distance L.sub.MIN to be maintained between two successive marked defects 11 according to the manufacturer's specifications. This leads to activation of a deflection device 224, via which the profile strand section following the first defect 11′ is deflected or diverted from the manufacturing line 200 processing the endless profile strand until the second defect 11″ arrives in the area of the separating device and can be detected by the separating device 222 (FIG. 4C). At this point, further profile strand has been removed from the strand accumulator 230 to continue feeding profile strand at a constant rate v.sub.260 to the adhesive strip station 260 and the downstream supply storage. Deflection of the control rocker continues to push upwards. The height H.sub.A2 in FIG. 4C is therefore further reduced compared to the height shown in FIG. 4B.

(20) In FIG. 4D, the profile strand section containing the defect 11″ is cut out by activating the separating device 222 and can be disposed of. The deflecting device 224 is deactivated because the detecting device 210 has not detected another marked defect in the area of the minimum distance L.sub.MIN. The strand profile fed to the adhesive strip station 260 is still removed from the strand accumulator 230 and its height H.sub.A2 is further reduced.

(21) In FIG. 4E, it can be seen how the separating end following the cut-out strand section is fed in the feed direction to the now activated joining device 226 and the two separating ends are joined to form a joint V (FIG. 2) in a manner known to the skilled person, while the strand profile fed to the adhesive strip station 260 is still taken from the strand accumulator 230.

(22) Finally, FIG. 4F shows how the manufacturing line is returned to the state shown in FIG. 4A after cutting out a defective section of the extruded profile. Cutting device 222, deflection device 224 and joining device 226 are deactivated. The previously generated joint V has in the meantime passed the control rocker, whose deflection now reacts with a downward yielding due to the control of the feed speed v.sub.220 to a value greater than v.sub.260, which is counteracted by increasing the height H.sub.A2 of the strand accumulator 230 while keeping the feed speed v.sub.260 constant, so that the strand accumulator 230 can be filled again.

(23) At the end of the second process section, the supply storage 250 is filled with an endless profile strand which—in accordance with the vehicle manufacturer's specifications—is free of defects and has joints of the highest quality over which an adhesive strip extends without interruption as shown in FIG. 2.

(24) The process sequence described in FIG. 3 and FIGS. 4A-4E and the allocation of individual process steps to the first or second process section or to the first or second manufacturing line can of course vary in individual cases.

(25) In particular, it can be provided that instead of or in addition to the specification of a minimum distance L.sub.MIN between successive flaws, a maximum number of flaws Z.sub.MAX in relation to a specific profile strand length is also or additionally used.

LIST OF REFERENCE SIGNS

(26) 1 Profile strand

(27) 2 first material area

(28) 3 second material area

(29) 4 Adhesive strip

(30) 5 Adhesive layer

(31) 6 Liner

(32) 7′/7″ first/second separating end

(33) 8 Joining compound

(34) 9 metallic foil/mass mixed with metal particles

(35) 10 defects

(36) 11 marked defects

(37) 100 first manufacturing line

(38) 102 Microwave

(39) 104 Spray cooling

(40) 106 Drying

(41) 108 Lacquering device

(42) 110 Lacquer drying

(43) 120 Inspection device

(44) 122 Camera

(45) 124 Marking device

(46) 130 First strand accumulator

(47) 150 Intermediate storage

(48) 200 second manufacturing line

(49) 210 Detecting device

(50) 220 Defect station

(51) 222 Separating device

(52) 224 Deflection device

(53) 226 Joining device

(54) 230 Second strand accumulator

(55) 240 Control rocker

(56) 242 Control rocker weight

(57) 250 Supply storage

(58) 260 Adhesive strip station

(59) V Joint

(60) A Receiving channel

(61) S Feed direction

(62) H.sub.A1 variable height of the first strand accumulator

(63) H.sub.A2 variable height of the second strand accumulator

(64) L.sub.MIN

(65) F.sub.G weight force acting on the control rocker arm

(66) V.sub.220 local feed speed

(67) V.sub.260 local feed speed