US3753634A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Molding means for strip frame semiconductive device
Assignee: Individual
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Filing: 1970-10-09
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Granted: 1973-08-21
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Expires: 1990-10-09
Abstract
Abstract In the step of plastic encapsulation of a semiconductive device, the inner ends of a group of leads comprising part of a lead frame, the semiconductive chip and the connections between the chip and the inner ends of the leads, are put into a cavity of a mold and fluid encapsulating material is forced into the cavity to surround the elements that are in the cavity with encapsulating material. A lead frame, which may be supplied in strip form, is provided, a part of which is so formed as to act as a gate for the admission of fluid encapsulating material into the mold cavity.
Inventors
- 👤 T Bliven
- 👤 J Hugill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 06:00
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/40; H10W70/421; H10W72/00; H10W72/01; H10W72/0198; H10W74/00; H10W74/01; H10W74/016; H10W72/50; H10W72/531; H10W72/5363; H10W90/00; H10W90/701; H10W90/751; H10W90/756
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
466 words
An apparatus facilitating the plastic encapsulation of electrical devices including in combination: lead frame means having first and second supporting bars running generally parallel to each other, and a plurality of cross bars running generally perpendicular to and having portions integral with said first and second supporting bars; a plurality of frame segments adjacent one another over the length of said lead frame means with each frame segment corresponding to an electrical device and with each frame segment defined by at least two portions of said first and second supporting bars and two portions of said cross bars which enclose an area in said frame segment; lead means integral with said supporting bars and extending into said area and adapted for connection with an electric means to be mounted in said area for electrical devices; one of said portions of said supporting bar portion having a predetermined opening therein which opens into said enclosed area; first mold means having a plurAlity of cavities positioned therein and corresponding to said frame segments of said lead frame means, each of said cavities having an enclosing wall with an exposed surface, said supporting and cross bar portions of each frame segment engaging said exposed surface of each wall when in molding position on said first mold means; second mold means superimposed on said first mold means and having a plurality of cavities therein corresponding to said cavities of said first mold means with each cavity of said second mold means being defined by a wall corresponding to the wall in a corresponding cavity of said first mold means, each of said walls of said second mold means having an exposed surface for engagement with one side of said supporting bar and cross bar portions of said lead frame means, with the opposite side of said portions of said lead frame means engaging said exposed surface of said corresponding wall of said first mold means; with one of said two mold means having a channel therein extending longitudinally to said mold means and adjacent to but spaced from and not connected with any of said plurality of cavities in said one mold means, said channel having an open face; said channel being closed at said open face thereof by engagement with a supporting bar except at a predetermined opening to provide a passage from said channel into said cavity through said predetermined opening for the flow of liquid encapsulating material through said channel and through said opening to encapsulate that within the cavity; and said opening, said first mold means, said second mold means and said supporting bar portion between the two mold means thereby cooperating to form said passage between said channel and said cavity, said passage controlling the flow of encapsulating material from said channel into said cavity.
Claim 2
Independent Claim
466 words
An apparatus facilitating the plastic encapsulation of electrical devices including in combination: lead frame means having first and second supporting bars running generally parallel to each other, and a plurality of cross bars running generally perpendicular to and having portions integral with said first and second supporting bars; a plurality of frame segments adjacent one another over the length of said lead frame means with each frame segment corresponding to an electrical device and with each frame segment defined by at least two portions of said first and second supporting bars and two portions of said cross bars which enclose an area in said frame segment; lead means integral with said supporting bars and extending into said area and adapted for connection with an electric means to be mounted in said area for electrical devices; one of said portions of said supporting bar portion having a predetermined opening therein which opens into said enclosed area; first mold means having a plurAlity of cavities positioned therein and corresponding to said frame segments of said lead frame means, each of said cavities having an enclosing wall with an exposed surface, said supporting and cross bar portions of each frame segment engaging said exposed surface of each wall when in molding position on said first mold means; second mold means superimposed on said first mold means and having a plurality of cavities therein corresponding to said cavities of said first mold means with each cavity of said second mold means being defined by a wall corresponding to the wall in a corresponding cavity of said first mold means, each of said walls of said second mold means having an exposed surface for engagement with one side of said supporting bar and cross bar portions of said lead frame means, with the opposite side of said portions of said lead frame means engaging said exposed surface of said corresponding wall of said first mold means; with one of said two mold means having a channel therein extending longitudinally to said mold means and adjacent to but spaced from and not connected with any of said plurality of cavities in said one mold means, said channel having an open face; said channel being closed at said open face thereof by engagement with a supporting bar except at a predetermined opening to provide a passage from said channel into said cavity through said predetermined opening for the flow of liquid encapsulating material through said channel and through said opening to encapsulate that within the cavity; and said opening, said first mold means, said second mold means and said supporting bar portion between the two mold means thereby cooperating to form said passage between said channel and said cavity, said passage controlling the flow of encapsulating material from said channel into said cavity.
Claim 3
Dependent Claim
25 words
The apparatus of claim 1 wherein: said predetermined opening is located in said supporting bar covering said channel and between two of said lead means.
Claim 4
Dependent Claim
72 words
The apparatus of claim 1 further including: third and fourth supporting bars running substantially parallel to said first and second supporting bars; said cross bars extending generally perpendicular to said first and second supporting bars to respectively join said third and fourth supporting bars; and said lead means having portions extending from said first supporting bar toward said third supporting bar and from said second supporting bar toward said fourth supporting bar.
Claim 5
Dependent Claim
253 words
A molding system for encapsulating a device comprising a lead frame of conductive material which includes a support bar and leads extending from the support bar so that the inward ends of leads are adjacent each other, an electrical unit mounted in the lead frame and conductively connected to leads, first and second mold portions for a mold having registering cavity portions to receive the inner ends of said leads and the electrical unit in a mold cavity formed by said cavity portions, a runner groove extending in said first mold portion, and positioned to extend along said mold and spaced from said mold cavity and registering at least in part with said support bar when said mold portions are properly positioned with respect to said lead frame for encapsulating the inner ends of said leads and said electrical unit and said conductive connections, said runner groove extending along said support bar, said support bar being so formed that said runner groove communicates with said mold cavity through a space in the formation of said support bar, the width of said support bar with which said runner groove registers being at least as great as the width of said runner groove for at least a portion of the length of said support bar, and said registering support bar is so narrowed in a portion at the space in the formation thereof as to cause communication between said runner groove and said mold cavity by way of said narrowed portion of said support bar.
Claim 6
Dependent Claim
253 words
A molding system for encapsulating a device comprising a lead frame of conductive material which includes a support bar and leads extending from the support bar so that the inward ends of leads are adjacent each other, an electrical unit mounted in the lead frame and conductively connected to leads, first and second mold portions for a mold having registering cavity portions to receive the inner ends of said leads and the electrical unit in a mold cavity formed by said cavity portions, a runner groove extending in said first mold portion, and positioned to extend along said mold and spaced from said mold cavity and registering at least in part with said support bar when said mold portions are properly positioned with respect to said lead frame for encapsulating the inner ends of said leads and said electrical unit and said conductive connections, said runner groove extending along said support bar, said support bar being so formed that said runner groove communicates with said mold cavity through a space in the formation of said support bar, the width of said support bar with which said runner groove registers being at least as great as the width of said runner groove for at least a portion of the length of said support bar, and said registering support bar is so narrowed in a portion at the space in the formation thereof as to cause communication between said runner groove and said mold cavity by way of said narrowed portion of said support bar.
Claim 7
Dependent Claim
49 words
In a molding system as defined in claim 4 wherein the support bar is narrowed in a plurality of portions, and plastic fluid passes along the runner groove in the mold portion and into the mold cavity through each of the plurality of narrowed portions of the support bar.
Claim 8
Dependent Claim
327 words
A molding system for plastic encapsulating an electrical device including the combination of a mold having runner means therein and a one-piece lead frame with which to assemble the electrical device to be encapsulated, wherein gate means is provided in the lead frame cooperating with runner means in the mold, said system including a one-piece lead frame which has therewith a plurality of leads, a support bar integral with leads, and cross bar means positioned outside the leads integral with the support bar and extending transversely to said support bar in the lead frame, an electrical unit mounted in the lead frame and conductively connected to each lead, first and second mold portions for the mold in said system, and a cavity portion in each said mold portion oppositely positioned to one another with the cavity portions together providing a mold cavity for the reception of fluid plastic to encapsulate a portion of each lead and the electrical unit conductively connected to said leads, with said runner means being in one of said mold portions adjacent the cavity for passage in the mold of encapsulating fluid plastic, and said gate means in the lead frame in said system comprising at least one notch in said support bar, said notched support bar, when the lead frame is in the mold, extending longitudinally of said runner means and covering the same except at said notch, and with said notch serving as a gate means for permitting passage of encapsulating fluid plastic from said runner means through said notch directly into said mold cavity to encapsulate the portion of each lead and the electrical unit and conductive connections therefrom in said mold cavity, said gate means comprising the only outlet from said runner means to said mold cavity for the flow of encapsulating fluid plastic into said mold cavity, and with said support bar and said cross bar means being severable from said lead frame after said encapsulation is accomplished.
Claim 9
Dependent Claim
327 words
A molding system for plastic encapsulating an electrical device including the combination of a mold having runner means therein and a one-piece lead frame with which to assemble the electrical device to be encapsulated, wherein gate means is provided in the lead frame cooperating with runner means in the mold, said system including a one-piece lead frame which has therewith a plurality of leads, a support bar integral with leads, and cross bar means positioned outside the leads integral with the support bar and extending transversely to said support bar in the lead frame, an electrical unit mounted in the lead frame and conductively connected to each lead, first and second mold portions for the mold in said system, and a cavity portion in each said mold portion oppositely positioned to one another with the cavity portions together providing a mold cavity for the reception of fluid plastic to encapsulate a portion of each lead and the electrical unit conductively connected to said leads, with said runner means being in one of said mold portions adjacent the cavity for passage in the mold of encapsulating fluid plastic, and said gate means in the lead frame in said system comprising at least one notch in said support bar, said notched support bar, when the lead frame is in the mold, extending longitudinally of said runner means and covering the same except at said notch, and with said notch serving as a gate means for permitting passage of encapsulating fluid plastic from said runner means through said notch directly into said mold cavity to encapsulate the portion of each lead and the electrical unit and conductive connections therefrom in said mold cavity, said gate means comprising the only outlet from said runner means to said mold cavity for the flow of encapsulating fluid plastic into said mold cavity, and with said support bar and said cross bar means being severable from said lead frame after said encapsulation is accomplished.
Claim 10
Dependent Claim
48 words
In the molding system of claim 6 wherein said lead frame has two support bars for support of said plurality of leads, with one of said support bars being wider than the other and said wider support bar having said notch therein to serve as a gate means.
Claim 11
Dependent Claim
53 words
In the molding system of claim 6 wherein said lead frame is one of a plurality of frames in an elongated metal strip and said mold has a plurality of mold cavities, runner means extending the length of the mold, and with the gate means in each frame cooperating with said runner means.
Claim 12
Dependent Claim
105 words
A molding system as defined in claim 6 wherein said plurality of leads is in two groups extending in opposite directions from one another, a pair of support bars spaced from one another and positioned generally parallel to one another, with each support bar integral with a corresponding one of said two groups of leads, said cross bar means comprising a pair of cross bars connecting the pair of support bars and extending transversely with respect to said support bars, with one of said support bars being notched to serve as said gate means for the flow of encapsulating fluid plastic into said mold cavity.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-20 | 1977-02-19 | 1977-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-20 | 1981-02-19 | 1981-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-20 | 1985-02-19 | 1985-08-21 | $7700.00 | Window Closed / Lapsed |