Dab tsi yog Undercut?
Txhua lub geometry uas kaw qhov chaw rau hauv lub hauv paus lossis kab noj hniav tom qab molding. Piv txwv li:
Snap- haum hooks
Sab qhov los yog qhov qhib
Xov (internal los yog sab nraud)
Recessed tav los yog bosses
Kev daws rau Undercuts
| Txoj kev | Nws ua haujlwm li cas | Zoo tshaj rau | Tus nqi cuam tshuam |
|---|---|---|---|
| Sliders (Side Cores) | Ib tug txav core retracts ua ntej ejection | Loj undercuts, sib sib zog nqus sab qhov, sab nraud nta | Nruab nrab mus rau siab |
| Lifters | Lub kaum sab xis lifts ib feem thaum nws ejects | Internal undercuts, me me snaps -fits | Nruab nrab |
| Bumpoff (Tshooj) | Saj zawg zog ib feem geometry yog deformed me ntsis thaum ejection | Cov ntaub ntawv yooj yim (PP, PE), me me undercuts | Tsawg |
| Tes Loads/Manual Inserts | Loose pieces ntxig thiab tshem tawm ntawm tes | Tsawg ntim, prototypes, complex undercuts | Tsawg tooling tab sis siab zog |
| Core Pullers (Hydraulic / Pneumatic) | Actuated slides rau loj los yog ntau undercuts | Cov pwm loj, ntau lawm | Siab |
Cov kev coj ua zoo tshaj plaws
1. Tsim rau Moldability Ua Ntej
Thaum twg los tau, tsis txhob undercuts los ntawm reorienting kab parting los yog hloov qhov geometry ib feem. Ib qho kev hloov me me tuaj yeem tshem tawm cov slider thiab txuag tau ntau txhiab daus las.
2. Xaiv txoj cai zoo
Sliders rau sab nraud undercuts ntawm kab noj hniav sab.
Lifters rau sab hauv undercuts ntawm lub hauv paus sab.
Bumpoffs tsuas yog rau cov resins hloov tau nrog txaus elongation.
3. Xav txog qhov ntim ntau lawm
Tsawg ntim (<10,000 parts): Bumpoffs or hand loads often make sense.
High volume (>100,000 qhov chaw): Kev nqis peev hauv cov sliders ruaj khov lossis cov nqa nqa nrog hnav- cov khoom tiv thaiv.
4. Tus account rau Slide thiab Lifter Clearance
Xyuas kom txaus qhov chaw nyob rau hauv pwm puag rau lub mechanism mus. Cov cuab yeej neeg coob ua rau muaj teeb meem hnav thiab tu thaum ntxov.
5. Siv cov hlau tsim nyog
Tsiv cov khoom xws li slides thiab lifters yuav tsum tau hardened steel (piv txwv li, H13, S136) tiv thaiv rov ua dua. Softer steels yuav khaus lossis hnav sai.