US3779506A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for equalizing the flow rate of molding compound into each of a series of mold cavities
Assignee: Motorola Solutions Inc
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Filing: 1971-08-25
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Granted: 1973-12-18
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Expires: 1991-08-25
Abstract
Abstract In a mold wherein there are a series of cavities to be filled from a single runner from which passageways, each including a gate, extend to each cavity, the velocity of molding or encapsulating compound into the cavities adjacent the end of the runner may be made the same as adjacent the beginning of the runner, by providing a dump cavity and a gate at the end of the runner to receive molding compound while the cavities adjacent the end of the runner are being filled.
Inventors
- 👤 V Adams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 00:29
CPC Classifications
B; B29; B29C; B29C45/00; B29C45/14; B29C45/17; B29C45/26; B29C45/27; B29C45/2701; Y; Y10; Y10S; Y10S425/00; Y10S425/812; Y10T; Y10T29/00; Y10T29/49; Y10T29/4998; Y10T29/49993
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
226 words
An injection mold wherein a series of mold cavities are filled from a runner in response to back pressure of flowing molding material developed in said runner comprising: a row of mold cavities, a supply opening for molding material, a runner for receiving said molding material in fluid form, said runner having a certain cross-sectional area, having a beginning end adjacent said supply opening, extending alongside said row of mold cavities, and having an end remote from said supply opening, a passageway reduced in cross-sectional area relative to the cross-sectional area of said runner extending from each one of said mold cavities to said runner for filling the associated cavity with fluid molding compound and determining the velocity of such compound into such cavity, and means associated with said remote end of said runner for receiving fluid molding material from said runner to control the velocity of molding compound flowing through the passageway into at least the one of said mold cavities immediately preceding said end to be essentially equal to the velocity of molding compound through said passageways of said mold cavities adjacent the beginning end of said runner as determined by the flow of fluid molding material in said runner, said means comprising a passageway reduced in cross-sectional area relative to the cross-sectional area of said runner and a dump cavity terminating said passageway.
Claim 2
Dependent Claim
226 words
An injection mold wherein a series of mold cavities are filled from a runner in response to back pressure of flowing molding material developed in said runner comprising: a row of mold cavities, a supply opening for molding material, a runner for receiving said molding material in fluid form, said runner having a certain cross-sectional area, having a beginning end adjacent said supply opening, extending alongside said row of mold cavities, and having an end remote from said supply opening, a passageway reduced in cross-sectional area relative to the cross-sectional area of said runner extending from each one of said mold cavities to said runner for filling the associated cavity with fluid molding compound and determining the velocity of such compound into such cavity, and means associated with said remote end of said runner for receiving fluid molding material from said runner to control the velocity of molding compound flowing through the passageway into at least the one of said mold cavities immediately preceding said end to be essentially equal to the velocity of molding compound through said passageways of said mold cavities adjacent the beginning end of said runner as determined by the flow of fluid molding material in said runner, said means comprising a passageway reduced in cross-sectional area relative to the cross-sectional area of said runner and a dump cavity terminating said passageway.
Claim 3
Dependent Claim
214 words
An injection mold wherein a series of mold cavities are filled from a runner in response to back pressure of flowing molding material developed in said runner comprising: a row of mold cavities, a supply opening for molding material, a runner for receiving said molding material in fluid form, said runner having a certain cross-sectional area, having a beginning end adjacent said supply opening, extending alongside said row of mold cavities, and having an end remote from said supply opening, a passageway reduced in cross-sectional area relative to the cross-sectional area of said runner extending from each one of said mold cavities to said runner for filling the associated cavity with fluid molding compound and determining the velocity of such compound into such cavity, and means associated with said end of said runner for receiving fluid molding material from said runner to control the velocity of molding compound flowing through said passageways into the mold cavities adjacent the said remote end of said runner to be eSsentially equal to the velocity of molding compound through said passageways of mold cavities adjacent the beginning end of said runner as determined by the flow of fluid molding material in said runner, said means comprising a restricted passageway, a gate and a dump cavity terminating said runner.
Claim 4
Dependent Claim
214 words
An injection mold wherein a series of mold cavities are filled from a runner in response to back pressure of flowing molding material developed in said runner comprising: a row of mold cavities, a supply opening for molding material, a runner for receiving said molding material in fluid form, said runner having a certain cross-sectional area, having a beginning end adjacent said supply opening, extending alongside said row of mold cavities, and having an end remote from said supply opening, a passageway reduced in cross-sectional area relative to the cross-sectional area of said runner extending from each one of said mold cavities to said runner for filling the associated cavity with fluid molding compound and determining the velocity of such compound into such cavity, and means associated with said end of said runner for receiving fluid molding material from said runner to control the velocity of molding compound flowing through said passageways into the mold cavities adjacent the said remote end of said runner to be eSsentially equal to the velocity of molding compound through said passageways of mold cavities adjacent the beginning end of said runner as determined by the flow of fluid molding material in said runner, said means comprising a restricted passageway, a gate and a dump cavity terminating said runner.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-17 | 1977-06-18 | 1977-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-17 | 1981-06-18 | 1981-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-17 | 1985-06-18 | 1985-12-18 | $7700.00 | Window Closed / Lapsed |