US5065933A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic device manipulating apparatus and method
Assignee: Nokia Bell Labs
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Filing: 1990-09-19
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Granted: 1991-11-19
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Expires: 2010-09-19
Abstract
Abstract A robotically controlled pick-uo to tool (11) is modified by connecting to it a load cell (26) that generates a signal indicative of stress on the pick-up tool. The pick-up tool is directed toward a chip (12) to be removed and movement is stopped when the load cell generates a first signal indicative of a first level of stress. In addition to stopping movement of the pick-up tool, the first signal actuates heating of the tool to a temperature sufficient to melt the solder (13) bonding the chip to the substrate (14). The melting of the solder bonds (13) results in a reduction of stress on the tool, which causes the load cell (26) to generate a signal indicative of the second level of stress. The second signal actuates the vacuum of the pick-up tool to cause adhesion of the chip to the pick-up tool and also initiates movement of the pick-up tool so as remove the chip from the substrate.
Inventors
- 👤 Nagesh R. Basavanhally
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:11
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K13/00; H05K13/04; H05K13/0486; B; B23; B23K; B23K1/00; B23K1/018; H10; H10W; H10W72/00; H10W72/071; H10W72/0711; H10W72/072
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
159 words
A method for removing an element that has been soldered to the surface of a substrate comprising the steps of: attaching a load cell to a vacuum pick-up tool, the load cell generating an electrical signal indicative of the mechanical stress of the tool against an object; causing the pick-up tool to contact and to bear against the soldered element until the load cell generates a first signal indicative of a first level of stress; in response to the first signal, heating the tool to a temperature sufficient to melt the solder bonding the element to the substrate, said melting resulting in a second level of stress on the tool which is smaller than the first level of stress, and further resulting in the load cell generating a second signal indicative of the second level of sress; in response to the second signal, actuating the pick-up tool; and using the pick-up tool to move the element from the substrate.
Claim 2
Independent Claim
159 words
A method for removing an element that has been soldered to the surface of a substrate comprising the steps of: attaching a load cell to a vacuum pick-up tool, the load cell generating an electrical signal indicative of the mechanical stress of the tool against an object; causing the pick-up tool to contact and to bear against the soldered element until the load cell generates a first signal indicative of a first level of stress; in response to the first signal, heating the tool to a temperature sufficient to melt the solder bonding the element to the substrate, said melting resulting in a second level of stress on the tool which is smaller than the first level of stress, and further resulting in the load cell generating a second signal indicative of the second level of sress; in response to the second signal, actuating the pick-up tool; and using the pick-up tool to move the element from the substrate.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein: the element in an integrated circuit chip.
Claim 4
Dependent Claim
41 words
The method of claim 1 wherein: the pick-up tool is a vacuum pick-up tool; and a vacuum is applied to the pick-up tool in response to the second signal so as to cause adhesion of the element to the pick-up tool.
Claim 5
Dependent Claim
32 words
The method of claim 3 wherein: automatic control circuits are used for heating the tool in response to the first signal and for applying a vacuum in response to the second signal.
Claim 6
Dependent Claim
25 words
The method of claim 4 wherein: the first signal stops movement of the pick-up tool; and the second signal initiates movement of the pick-up tool.
Claim 7
Dependent Claim
15 words
The method of claim 1 wherein: the load cell comprises at least one strain gauge.
Claim 8
Dependent Claim
22 words
The method of claim 6 wherein: the load cell comprises a pair of strain gauges connected as arms of a resistance bridge.
Claim 9
Dependent Claim
162 words
Apparatus for removing an element that has been soldered to the surface of a substrate comprising: a pick-up tool; means comprising a load cell connected to the pick-up tool for generating an electrical signal indicative of the mechanical stress of the tool against an object; means for causing the pick-up tool to contact and bear against the soldered element until the load cell generates a first signal indicative of a first level of stress; means responsive to the first signal for heating the tool to a temperature sufficient to melt the solder bonding the element to the substrate, said melting resulting in a second level of stress on the pick-up tool that is smaller than the first level of stress; means comprising the load cell for generating a second signal indicative of the second level of stress; and means responsive to the second signal for actuating the pick-up tool and for causing the pick-up tool to remove the element from the substrate.
Claim 10
Dependent Claim
162 words
Apparatus for removing an element that has been soldered to the surface of a substrate comprising: a pick-up tool; means comprising a load cell connected to the pick-up tool for generating an electrical signal indicative of the mechanical stress of the tool against an object; means for causing the pick-up tool to contact and bear against the soldered element until the load cell generates a first signal indicative of a first level of stress; means responsive to the first signal for heating the tool to a temperature sufficient to melt the solder bonding the element to the substrate, said melting resulting in a second level of stress on the pick-up tool that is smaller than the first level of stress; means comprising the load cell for generating a second signal indicative of the second level of stress; and means responsive to the second signal for actuating the pick-up tool and for causing the pick-up tool to remove the element from the substrate.
Claim 11
Dependent Claim
13 words
The apparatus of claim 8 wherein: the element is an integrated circuit chip.
Claim 12
Dependent Claim
41 words
The apparatus of claim 8 wherein: the pick-up tool is a vacuum pick-up tool; and further comprising; means responsive to the second signal for applying a vacuum to the pick-up tool, thereby causing adhesion of the element to the pick-up tool.
Claim 13
Dependent Claim
31 words
The apparatus of claim 1 further comprising: automatic control circuits for heating the tool in response to the first signal and for applying a vacuum in response to the second signal.
Claim 14
Dependent Claim
34 words
The apparatus of claim 11 further comprising: means responsive to the first signal for stopping movement of the pick-up tool; and means responsive to the second signal for initiating movement of the pick-up tool.
Claim 15
Dependent Claim
13 words
The apparatus of claim 8 wherein: the load cell comprises a strain gauge.
Claim 16
Dependent Claim
22 words
The apparatus of claim 13 wherein: the load cell comprises first and second strain gauges connected as arms in a resistance bridge.
References Cited (Backward Citations)
US4295596A
Cited
US4577513A
Cited
US4611296A
Cited
US4561586A
Cited
US4854494A
Cited
US4923521A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-11-18 | 1995-05-20 | 1995-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-11-18 | 1999-05-20 | 1999-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-11-18 | 2003-05-20 | 2003-11-19 | $7700.00 | Window Closed / Lapsed |