Ultrasonic vuam txheej txheem tsis
Cov txheej txheem tseem ceeb ntawm ultrasonic vuam yog: kev ua kom dav, lub sijhawm vuam, tuav lub sijhawm siab, vuam siab, zaus, thiab lwm yam. Qhov hloov kho ntawm vuam tsis nyob ntawm qhov loj me thiab nruj ntawm qhov, tshwj xeeb tshaj yog qhov kev ncua deb ntawm qhov chaw tiv tauj ntawm lub taub hau vuam thiab vuam sib koom ua ke. Lub peev xwm vuam tsuas yog txwv los ntawm yas' s muaj peev xwm kis tau ultrasonic kev co (thiab cov seem tsis puas).
1 zaus
Nquag siv cov nquag siv rau ultrasound yog 20, 30, thiab 40 kHz, thiab 15 kHz feem ntau siv rau cov nplai ib nrab crystalline. 20 kHz yog qhov feem ntau siv ultrasonic zaus, vim hais tias qhov ntau thiab lub zog tsim nyog rau melting thermoplastics ntawm qhov zaus no tau yooj yim, tab sis nws yuav tsim ntau cov tshuab kev co uas nyuaj rau kev tswj hwm, thiab lub cuab tam tau loj heev. Ib qhov ntau zaus dua (40 kHz) uas ua rau muaj kev co qis yog ua tau, thiab feem ntau siv rau vuam engineering plastics thiab cov muaj zog polymers. Qhov zoo ntawm cov khoom siv vuam ntau muaj xws li: suab nrov qis, qhov me me ntawm qhov loj me, txhim kho feem ntawm kev tiv thaiv (vim txo qis kev ntxhov siab thiab tsis muaj cua sov ntawm qhov chaw sab nraud ntawm qhov sib txuam sib txuam), txhim kho lub zog ua kom tsis muaj zog, qis dua vuam lub zog, thiab nrawm dua kev ceev. Qhov tsis zoo yog tias nws nyuaj rau kev ua kom deb li deb vuam vim yog qhov me me ntawm qhov seem, txo hwj chim loj thiab txo qhov nrawm. Ntau qhov loj dua ultrasonic vuam tshuab feem ntau yog siv los txuas cov me me, qhov chaw ua haujlwm (xws li lub tshuab hluav taws xob) thiab qhov chaw uas yuav tsum muaj cov khoom pov thawj tsawg. Tus 15 kHz qhov txuas tau sai sai weld feem ntau thermoplastics, feem ntau, cov khoom siv tsawg dua qhov cuam tshuam qis dua li 20 kHz qhov txuas. Cov seem uas tsis tuaj yeem yog welded nrog 20 kHz (tshwj xeeb tshaj yog cov ua los ntawm cov roj hmab ua tau zoo thiab cov thev naus laus zis thev naus laus zis thiab cov khoom siv) tuaj yeem txuas tau zoo nrog 15 kHz. Ntawm qis zaus zaus, vuam taub hau muaj lub ntsej muag ntev dua thiab tuaj yeem ua qhov loj dua rau txhua qhov ntev. Lwm qhov kom zoo dua ntawm kev siv 15 kHz yog tias piv nrog kev siv ntau dua, nws zoo heev txo cov attenuation ntawm ultrasonic vuam hauv plastics, tso cai rau cov hlau txuas ntawm softer plastics thiab ntau qhov chaw nyob deb.
2 amplitude
Kev vam meej ntawm vuam nyob ntawm txoj kev tsim nyog ntawm qhov kawg ntawm lub taub hau vuam. Rau txhua lub horn / vuam sib txuas lub taub hau, qhov ntau ntxiv tag nrho. Xaiv qhov ntau raws li cov khoom siv los yog welded kom tau txais qhov ntsuas kev tsim nyog ntawm melting. Feem ntau hais lus, semi-crystalline plastics yuav tsum muaj lub zog ntau dua li cov uas tsis muaj crystalline plastics, thiab yog li ntawd xav tau ntau dua qhov ntau ntawm cov kawg. Cov txheej txheem kev tswj ntawm niaj hnub siv tshuab ultrasonic vuam tso cai rau gradation. Lub siab siv tau siv los pib melting, thiab qhov tsawg kawg yog siv los tswj cov viscosity ntawm cov khoom siv dag. Ua kom ntxiv dag zog yuav txhim kho qhov weld zoo ntawm chais shear tsim qhov. Rau cov pob qij txha txuas, thaum lub dav zuj zus ntxiv, lub weld zoo txhim kho thiab lub sijhawm vuam txo. Hauv ultrasonic vuam nrog lub zog taw qhia, qhov nruab nrab ntawm qhov kub tsis txaus (Qavg) yog nyob ntawm cov txheej txheem hluav taws xob tsis zoo (Eʺ), zaus (ω) thiab ua yeeb yam (ε 0) ntawm cov khoom siv: Qavg=ωε 02 Eʺ / 2
Cov sib txuas hluav taws xob tsis sib txuas ntawm cov thermoplastics zoo sib xws nrog rau qhov kub thiab txias. Thaum lub ntsiab lus melting los yog lub iav hloov qhov kub tau mus txog, qhov poob lawm modulus nce thiab ntau lub zog hloov mus rau hauv tshav kub. Tom qab cov cua sov pib, qhov kub ntawm qhov chaw sib tshuam vuam nce siab (txog 1 000 ℃ / s). Tus cwj pwm coj cwj pwm yog qhov sib npaug rau lub zog ntawm vuam lub taub hau, yog li ntawd cov cua sov ntawm lub vuam sib txuas tuaj yeem tswj tau los ntawm kev hloov pauv ntau yam. Amplitude yog qhov tseem ceeb uas ntsuas qhov ntsuas ntws ntawm thermoplastic extrusion. Thaum lub amplitude siab, qhov vuam interface cua sov ua rau siab dua, qhov kub nce, thiab cov khoom siv molten ntws nrawm dua, uas ua rau muaj qhov nce ntawm cov txheej txheem molecular, ntau cov flashes thiab qis weld lub zog. Siab amplitude yog tsim nyog los pib melting. Tsawg dhau lawm ib qho tsis tuaj yeem ua rau cov yaj tsis sib xws thiab ua tsis tau thaum ntxov. Thaum lub amplitude muaj ntau ntxiv, ntau qhov kev co lub zog ntawm lub zog siv nyob hauv cov thermoplastic, thiab cov seem yuav tsum tau txuas nrog yog qhov kev ntxhov siab ntau dua. Thaum lub amplitude tsis tu ncua thoob plaws lub voj vuam, qhov ntau tshaj plaws uas yuav tsis ua rau muaj kev puas tsuaj ntau rau cov ntu yuav tsum tau txuas yog feem ntau siv. Rau cov siv lead ua plastics xws li polyethylene thiab polypropylene, qhov cuam tshuam ntawm cov khoom siv dav yog ntau dua rau cov uas tsis muaj crystalline plastics xws li ABS thiab polystyrene. Qhov no tuaj yeem ua rau qhov xav tau ntau lub zog rau kev yaj thiab vuam ntawm cov kab hluav taws xob crystalline. Lub amplitude tuaj yeem hloov kho kev siv tshuab (los ntawm kev hloov lub tshuab raj lub taub hau lossis lub taub hau) lossis hluav taws xob (los ntawm kev hloov cov voltage uas tau xa mus rau lub tshuab hloov pauv). Hauv kev xyaum, qhov loj dua ntawm kev hloov kho loj yoog ib txoj kev siv tshuab thiab lub zog me siv cov qauv hluav taws xob. High melting point cov ntaub ntawv, deb-teb welds, thiab semi-crystalline plastics feem ntau yuav tsum ntau ntau dua li cov uas tsis yog-crystalline uas thiab ze-teb welds. Feem ntau tag nrho cov kev ua kom dav ntawm amorphous plastics yog 30-100 μm, thaum lub sijhawm ntawd ntawm cov kab hluav taws xob crystalline yog 60-125 μm. Amplitude profiling tuaj yeem ua tiav zoo melt ntws thiab ua tau zoo weld lub zog loj. Rau kev sib xyaw ua ke thiab qib quab yuam, qhov siab dav thiab quab yuam tau siv los pib yaj, thiab tom qab ntawd qhov khoo thiab cov quab yuam txo kom txo qhov molecular orientation raws txoj kab weld.
3 Vuam lub sijhawm
Lub sijhawm vuam yog lub sijhawm thaum kev vibration tau siv. Lub sijhawm tsim nyog vuam rau txhua daim ntawv thov yog txiav txim los ntawm kev sim. Ua kom lub sijhawm vuam ntxiv yuav ua rau muaj zog ntawm lub weld kom txog rau thaum lub sijhawm ua haujlwm siab. Ib qho kev nce ntxiv ntawm vuam lub sijhawm yuav ua rau txo qis ntawm weld lub zog lossis tsuas yog nce me ntsis ntawm lub zog, thaum tib lub sijhawm nws yuav nce weld flash thiab nce ntxiv ntawm qee qhov kev poob haujlwm. Nws yog ib qho tseem ceeb kom tsis txhob cuam tshuam kev siv hlau ntau, vim tias nws yuav tsim cov nyem ntau dhau uas yuav tsum tau txiav, uas yuav txo qhov zoo ntawm cov hlau txuas thiab tsim kom muaj xau hauv qhov chaw uas yuav tsum tau muab khi ua ke. Lub taub hau vuam tuaj yeem kos cov nplaim. Rau lub sijhawm ua haujlwm ntev dua, lub sijhawm yaj thiab pob txha lov kuj tseem tuaj yeem tshwm sim rau hauv qhov chaw kom deb ntawm thaj chaw sib koom tes, tshwj xeeb tshaj yog nyob ntawm qhov, txuas cov kab thiab lub pob ntse nyob hauv qhov pwm.
4 Tuav sijhawm
Tuav lub sijhawm siab txhawm rau hais txog lub sijhawm nominal rau cov ntu kom sib xyaw thiab khov kho hauv qab kev co-nias siab tom qab vuam. Feem ntau, nws tsis yog qhov tseem ceeb tsis txaus, 0.3 ~ 0.5 s yog feem ntau txaus, tshwj tsis yog kev thauj khoom sab hauv yog yooj yim rau kev rho tawm ntawm qhov chaw welded (xws li coil caij nplooj ntoos hlav compressed ua ntej welding).
5 lub siab
Lub vuam siab muab lub zog zoo li qub uas xav tau rau kev sib txuas ntawm lub taub hau vuam thiab rau ntu kom qhov kev co tuaj yeem xa mus rau hauv ib feem. Thaum cov molten khoom ntawm qhov sib koom ua ke lub zog thaum lub siab tuav theem ntawm lub vuam kev ua haujlwm, tib lub thauj zoo li qub kom paub meej tias cov seem. Qhov kev txiav txim siab ntawm kev pom qhov siab yog qhov tseem ceeb rau kev ua haujlwm zoo. Yog tias lub siab poob qis, nws yuav ua rau tsis zoo lossis tsis txaus siab nthwv dej rau hauv qhov hloov mus rau lub zog, ua rau muaj qhov tsis tseem ceeb rau vuam ntev mus ntev. Ua kom lub vuam siab ntxiv yuav txo qhov vuam sij hawm kom ua tiav qhov ua haujlwm tib yam. Yog tias lub siab dhau dhau lawm, nws yuav ua rau muaj qhov sib qhia txog molecular raws qhov kev taw qhia ntws thiab txo lub zog ntawm lub weld, uas yuav ua rau qee qhov tsis muaj chaw. Thaum muaj teeb meem loj tshaj plaws, yog tias lub siab siab dhau ntawm qhov txheeb ze ntawm qhov kawg ntawm lub vuam taub hau, nws yuav dhau dhau thiab nres lub taub hau vuam. Hauv ultrasonic welding, qhov loj siv yuav tsum tau ua kom muaj qhov siab, thiab tsawg zaus yuav tsum muaj qhov siab. Raws li tus amplitude tsub kom, txais tau siab khwv. Yog li no, qhov tseem ceeb tshaj plaws rau kev ua haujlwm siab yog nrhiav qhov siab zoo. Feem ntau cov vuam ultrasonic ua tiav los ntawm kev txiav txim siab tas li lossis lub zog tas li. Rau qee lub cuab yeej, lub zog tuaj yeem hloov tau thaum lub voj voog, uas yog, lub zog profiling raug ua, thiab lub zog vuam txo thaum lub sijhawm thov ultrasonic zog rau ntu. Lub vuam nyem lossis quab yuam uas poob rau ntawm qhov kawg ntawm lub voj vuam txo qhov nyiaj ntawm cov khoom sib txuas los ntawm qhov sib koom tes, ntev lub sij hawm diffusion ntawm molecules, txo cov kev taw qhia molecular thiab nce lub zog ntawm weld. Rau cov ntaub ntawv nrog qis yaj viscosity zoo ib yam li polyamide, qhov no yuav ntau ntxiv lub zog weld.
6 Vuam hom
Vuam raws lub sijhawm yog hu ua txoj kev qhib lub voj. Cov seem yuav tsum tau welded yog sib sau ua ke ntawm qhov ua ntej ua haujlwm vuam taub hau thiab kov. Tom qab ntawd lub ultrasonic yoj ua haujlwm rau cov khoom siv rau lub sijhawm ruaj khov, feem ntau yog 0.2 txog 1 s. Kev vam meej vuam tsis tau tshwm sim thaum txoj haujlwm no. Kev vam meej vuam yog qhov xwm txheej zoo tshaj plaws nyob rau hauv qhov kev xav tias lub sijhawm vuam ruaj ruaj ua rau lub zog ruaj khov ntawm kev sib koom tes ntawm qhov sib koom tes, uas ua rau tswj tau cov nyiaj melting. Qhov tseeb, lub hwj chim nqus tau los ntawm kev tswj lub amplitude los ntawm ib lub voj voog mus rau tom ntej tsis zoo li qub. Qhov no yog vim muaj ntau yam (xws li haum ntawm ob ntu). Vim tias lub zog hloov nrog lub zog thiab lub sijhawm, thiab lub sijhawm tau hloov pauv, lub zog siv yuav hloov ntawm ib ntu mus rau lwm qhov. Rau huab hwm coj ntau qhov twg sib xws yog qhov tseem ceeb, qhov no yog qhia meej yam tsis xav tau. Lub zog vuam hluav taws xob yog lub voj kev kaw nrog lub tswv yim tswj hwm. Ultrasonic tshuab software ntsuas ntsuas lub zog nqus thiab kho cov sijhawm ua haujlwm kom xa cov lus xav tau ntawm lub zog mus rau kev sib koom tes. Qhov kev xav ntawm qhov txheej txheem no yog tias yog lub zog siv los ntawm txhua lub weld yog qhov qub, tus nqi ntawm cov khoom siv ntawm qhov sib koom ua ke yog tib yam txhua lub sijhawm. Txawm li cas los xij, qhov xwm txheej tiag tiag yog tias muaj lub zog poob hauv cov khoom siv vuam vuam thiab tshwj xeeb tshaj yog nyob ntawm qhov kev sib tshuam ntawm vuam taub hau thiab ntu. Raws li qhov tshwm sim, qee qhov chaw yuav tau txais lub zog ntau dua li lwm qhov, uas yuav ua rau tsis muaj qhov txuas tsis sib haum. Vuam los ntawm kev deb tso cai rau ntu tau koom nrog ntawm qhov tshwj xeeb vuam txuas. Hom kev ua haujlwm no tsis nyob ntawm lub sijhawm, nqus lub zog lossis lub zog, thiab them nyiaj rau txhua qhov kev sib txawv ntawm qhov pwm, yog li qhov zoo tshaj plaws kom ntseeg tau tias tib cov yas ploj nyob rau hauv qhov sib koom ua ke txhua zaus. Txhawm rau tswj hwm qhov ua tau zoo, ib qho kev txwv tau teeb tsa lub zog lossis lub sijhawm siv los tsim lub weld
