A kind of automobile cavity intercepts offset plate and preparation method thereof
Technical field
The present invention relates to a kind of automobile-used material and corresponding preparation method, in particular, it relates to a kind of automobile cavity and intercepts offset plate and preparation method thereof.
Background technology
The NVH characteristic, be that noise, vibration and sound vibration roughness overall characteristic are the integrated technology indexs of weighing the Hyundai Motor manufacture level, it is the important component part of the various brands vehicle market competitiveness, therefore each big car load manufacturing enterprise and auto parts and components enterprise think little of this nothing, promote the NVH characteristic of automobile one after another by every means.Have some cavity members in the body structure of automobile,, in the galloping process, form high velocity air in the cavity, produce wind and make an uproar as central post and roof side rail, and and then be delivered in the car, cause and take discomfort.At this noise like controlling party face, at present mainly be to adopt packing material to carry out air-flow to intercept and reach the noise reduction purpose in the prior art.Material commonly used is an expansion offset plate material, before the welding of cavity member, expansion offset plate material is attached on the cavity inner wall, and in the baking operation behind electrophoresis, expansion glue expanded by heating, thus filled chamber intercepts air-flow, subdues wind and makes an uproar.This type of expansion offset plate material is solid material, can obviously increase car weight after large tracts of land is used.Notification number is that the utility model patent of CN201677832U discloses a kind of automobile cavity internal sound insulation blob of viscose on December 22nd, 2010, this utility model comprises rack body, rack body is fixedlyed connected with the vehicle body panel beating by buckle, because being machinery, this sound insulation blob of viscose and panel beating install, compare with the gluing fixed form that existing expansion glue is common, fixing more firm, but this sound insulation blob of viscose exists large tracts of land use meeting obviously to increase the problem of car weight also as existing expansion glue.
Summary of the invention
For the filling material density that overcomes existing vehicle cavity member solid construction relatively large, large tracts of land is used the defective that can obviously increase car weight, the invention provides a kind of a kind of automobile cavity obstruct offset plate inside and outside composite construction, that global density is less that has.
Technical scheme of the present invention is: a kind of automobile cavity intercepts offset plate, and its integral body is composite construction, but comprises inner core made from elastic porous material and the external capsule made from the expanded material of expanded by heating, and external capsule is coated on outside the inner core.Existing automobile cavity barrier material all is solid materials, and automobile cavity obstruct offset plate provided by the invention is composited by density less elastic porous material and expandable expanded material, therefore this automobile cavity obstruct offset plate is lighter than the existing solid material weight of equal volume, and the car weight that large tracts of land uses the back to increase is less relatively.Before the operation that is welded, this automobile cavity is intercepted offset plate and be attached to cavity member inboard, finish be welded and electrophoresis after, the cavity member enters roasting procedure, around here, under 180 ℃ temperature, the automobile cavity intercepts the external capsule foaming and intumescing of offset plate, it surrounds the inner chamber that forms and enlarges, the volume of the inner core that compresses also recovers thereupon gradually, after the external capsule cooled and solidified that finishes to be baked, the external capsule of expansion fills up the cavity member space in the rubberizing section, the air-flow in the blocking-up cavity, at this moment, the density of external capsule is 20g/cm
3~30g/cm
3, the density of inner core is 5g/cm
3~10g/cm
3, two kinds of formed density gradients of material have increased the difficulty of sound wave by material itself, and inner core itself also has the effect that absorbs sound wave simultaneously, can obtain desirable noise reduction and less increase car weight so use this automobile cavity to intercept offset plate.
As preferably, described inner core material is a melamine resin foam.This material has the microstructure of three dimensional network trellis, and high percent opening is arranged, and this makes sound wave energy effectively enter the material deep layer, and changes the vibration of sound wave the vibration of grid into, sound wave is consumed in a large number and absorbs, and effectively eliminate back wave.This in addition material also has excellent compressibility.
As preferably, described outer capsule material is the ethylene propylene diene rubber that is mixed with blowing agent.The ethylene propylene diene rubber resistance to oxidation, anti-erosion can add filler in a large number and the physical and mechanical properties range of decrease is little, can stand 20 minutes 180 ℃ high-temperature baking in the roasting procedure behind the electrophoresis, is the material of desirable processing external capsule.
As preferably, the integral thickness that described automobile cavity intercepts offset plate is 2mm to 8mm.The setting of this size range is the convenience in order to process, to store and using.
As preferably, the outer surface of described external capsule is provided with adhesive linkage.Adhesive linkage is convenient to automobile cavity obstruct offset plate and is sticked in the cavity member.The high temperature of this adhesive linkage in must can ovenable roasting operation.
A kind of automobile cavity intercepts the preparation method of offset plate, may further comprise the steps:
A. inner core cell cube preparation;
B. external capsule cell cube preparation;
C. clamp an inner core cell cube with two external capsule cell cubes, compound with the hot pressing compounding machine;
D. cut the matching edge that is compounded to form;
E. stick on double-sided tape at external capsule cell cube outer surface.
When this automobile cavity of preparation intercepted offset plate, inner core elder generation compression volume was compound with external capsule again.
As preferably, described inner core cell cube preparation method is, it is 40mm to 90mm that the foams of the inner core material melamine resin foam of outsourcing are cut into length, and width is 20mm to 50mm, and thickness is the cell cube of 5 mm to 12mm.Melamine resin foam production difficulty is higher, and more economical from the market buying at present, its physical and chemical performance can satisfy product design requirement of the present invention, need not deep processing, only need cut into the size that is applicable to the vehicle cavity member and get final product.
As preferably, described external capsule cell cube preparation may further comprise the steps:
A. the ethylene propylene diene rubber rubber is plasticated under 40 ℃ to 50 ℃ temperature in mill;
B. it is mixing under 100 ℃ to 120 ℃ temperature in banbury that ethylene propylene diene rubber after plasticating adds auxiliary agent, foaming agent ac, and wherein the dosage percentage of foaming agent ac is 2% to 5%;
C. mixing product is extruded into coiled material after adding the cold feed extruder fusion;
D. will extruding coiled material, to cut into length be 50mm to 100mm, and width is 35mm to 65mm, and thickness is the cell cube of 2mm to 6mm.
Plasticate, mixing and to extrude be ripe ethylene propylene diene rubber rubber preparation method, add dosage percentage on this basis and be 2% to 5% foaming agent ac, and cut by above-mentioned size, the physical and chemical performance of the product that makes and size are adapted at using on the vehicle cavity member most.
The invention has the beneficial effects as follows:
Falling wind makes an uproar effective.Its unique composite construction can absorb it again and slackens the noise sound wave in the air-flow in blocking-up cavity member.
Reduce the increase of car weight.It is low that the design feature that its outer empty pocket coats inner light material makes global density compare to existing solid material, and therefore the car weight that increases after under equal conditions a large amount of the use also still less compared with prior art can reduce oil consumption.
Description of drawings
The invention will be further described below in conjunction with drawings and the specific embodiments.
Fig. 1 is a kind of cutaway view of the present invention;
Fig. 2 is a kind of use schematic diagram of the present invention;
Fig. 3 is a kind of preparation flow figure of the present invention.
Among the figure, 1-inner core, 2-external capsule, 3-vehicle cavity member.
The specific embodiment
Embodiment 1
As depicted in figs. 1 and 2, a kind of automobile cavity intercepts offset plate, its integral body is composite construction, comprise inner core 1 and external capsule 2, inner core 1 is the melamine resin foam of BASF AG's production of market purchasing, external capsule 2 is for being mixed with the ethylene propylene diene rubber of foaming agent ac, and ethylene propylene diene rubber forms the empty pocket that wall thickness is 3mm, with the melamine resin foam integral coating in interior.It is long 86mm that the automobile cavity intercepts the offset plate finished product, and wide 50mm, the flexible rectangle sheet material of thick 7.5mm, automobile cavity intercept the bottom surface of offset plate and post 86mm length, the double-sided tape that 50mm is wide, coated with protective film on the glue face one.This automobile cavity intercepts offset plate and can make by preparation flow shown in Figure 3: prepare earlier inner core and external capsule respectively.The preparation of inner core can then cut growth 80mm, wide 44mm, the cell cube of thick 6mm directly from market purchasing melamine resin foam foams.External capsule prepares by following step:
A. the ethylene propylene diene rubber rubber is plasticated under 48 ℃ in mill;
B. it is mixing under 110 ℃ in banbury that the ethylene propylene diene rubber after plasticating adds auxiliary agent, foaming agent ac, and wherein the dosage percentage of foaming agent ac is 3%;
C. it is wide to be extruded into 60mm after the fusion of mixing product adding cold feed extruder, the coiled material that 3mm is thick;
D. will extrude coiled material and cut into the long ethylene propylene diene rubber cell cube of 100mm.
After finishing the preparation of inner core and external capsule, a melamine resin foam cell cube is clipped between two ethylene propylene diene rubber cell cubes, the position of melamine resin foam cell cube on the ethylene propylene diene rubber cell cube occupy the center, use the hot pressing compounding machine to carry out the compound of inner core 1 and exterior material 2, the hot pressing compounding machine is provided with the die cavity of a 86mm * 50 mm * 4.5mm, melamine resin foam cell cube and ethylene propylene diene rubber cell cube that will be compound be placed in the die cavity between two parties, with the press-down type pressing plate that has heating head trilaminate material is compressed, the thickness of melamine resin foam cell cube is compressed into about 1.5mm by former 6mm, with the hot pressing fusion respectively of two ethylene propylene diene rubber cell cube four limits, finish the compound of inner core 1 and external capsule 2 simultaneously.At last the superimposed ledge of two ethylene propylene diene rubber cell cubes is cut out go and the material bottom after compound stick on can anti-180 ℃ of temperature double-sided tape, just finish the preparation that the automobile cavity intercepts the offset plate monomer.
Embodiment 2
It is long 52mm that the automobile cavity intercepts the offset plate finished product, and wide 30mm, the flexible rectangle sheet material of thick 4mm, automobile cavity intercept the bottom surface of offset plate and post 52mm length one, and the double-sided tape that 30mm is wide, external capsule wall thickness are 1mm.Inner core 1 is long 50mm, wide 28mm, the melamine resin foam of thick 6mm, external capsule 2 is mixing down for plasticated, add 108 ℃ of 4% blowing agents under 46 ℃ by the ethylene propylene diene rubber rubber, and the 40mm that forms after the extrusion molding is wide, it is the ethylene propylene terpolymer sheet of 60 mm that the thick coiled material of 1mm cuts the length that forms, and is 52mm * 30 mm * 2mm in order to the cavity dimension on the compound hot pressing compounding machine of inner core and exterior material, and compound back inner core thickness is compressed into 2mm.All the other are with embodiment 1.
During use, before the operation that is welded, the automobile cavity for preparing is intercepted offset plate is attached to vehicle cavity member 3 by the double faced adhesive tape of its bottom inboard, finish be welded and electrophoresis after, vehicle cavity member 3 enters roasting procedure, around here, under 180 ℃ temperature, outer capsule material ethylene propylene diene rubber foaming expands, it surrounds the inner chamber that forms and enlarges, the volume of inner compacted melamine resin foam cell cube also recovers thereupon gradually, after the external capsule material cooled that finishes to be baked is solidified, the external capsule that expands fills up cavity member 3 spaces in the rubberizing section, air-flow in the blocking-up cavity, the volume of melamine resin foam cell cube restores or recovers most of simultaneously, can bring into play the effect of absorption of noise sound wave.