US3827619A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ultrasonic bond monitor
Assignee: United States Department of the Navy
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Filing: 1973-01-19
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Granted: 1974-08-06
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Expires: 1993-01-19
Abstract
Abstract A system and method for monitoring the bond strength of ultrasonic bonds. A measure of bond quality is obtained nondestructively, by developing a voltage which is proportional to the amplitude of the traverse motion of the ultrasonic bonding tool, and also developing, by means of a transducer, a second voltage proportional to the tangential component of the forces applied during bonding. The voltages are fed into a logic circuit to derive their ratio, which is a measure of the bonding quality.
Inventors
- 👤 A Hamamoto
- 👤 J Bellin
- 👤 J Cusick
- 👤 A Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:00
CPC Classifications
H; H10; H10W; H10W99/00; B; B23; B23K; B23K20/00; B23K20/10; H10W72/00; H10W72/071; H10W72/0711; H10W72/075; H10W72/07531; H10W72/07532; H10W72/07533; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49764; Y10T29/49771; Y10T29/49774
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
106 words
Apparatus for indicating the quality of a bond made by an ultrasonic bonder during the bonding process comprising: means for developing a first electrical signal proportional to a tangential force applied to the materials being bonded during the bonding process; means for developing a second electrical signal proportional to the amplitude of a traverse motion of the bonding tool; means for combining the first and second electrical signals to produce an output signal equal to the ratio of the first electrical signal to the second electrical signal; and means for displaying the output from the signal combining means so that poor bonds may be readily detected.
Claim 2
Dependent Claim
106 words
Apparatus for indicating the quality of a bond made by an ultrasonic bonder during the bonding process comprising: means for developing a first electrical signal proportional to a tangential force applied to the materials being bonded during the bonding process; means for developing a second electrical signal proportional to the amplitude of a traverse motion of the bonding tool; means for combining the first and second electrical signals to produce an output signal equal to the ratio of the first electrical signal to the second electrical signal; and means for displaying the output from the signal combining means so that poor bonds may be readily detected.
Claim 3
Dependent Claim
27 words
The apparatus of claim 1 wherein the means for developing the first electrical signal is a pick-up coil coupled to the drive wire of the ultrasonic bonder.
Claim 4
Dependent Claim
25 words
The apparatus of claim 2 wherein the second electrical signal generating means is a piezoelectric transducer in contact with the material undergoing the bonding process.
Claim 5
Dependent Claim
14 words
The apparatus of claim 3 wherein the transducer is a zirconate-lead titanate ceramic disc.
Claim 6
Dependent Claim
75 words
The apparatus of claim 4 wherein the means for combining the first and second electric signals comprises: means for converting the first and second signals to first and second logarithmic voltages; a difference amplifier connected to the converting means having an output equal to the difference between the first and second logarithmic signals; a sample and hold circuit connected to the difference amplifier; and means for displaying the output of the sample and hold circuit.
Claim 7
Dependent Claim
76 words
The apparatus of claim 5 wherein the converting means are first and second identical channels comprising: a preamplifier receiving the output of the transducer and pick-up coil respectively; a detector connected to the preamplifier; a high impedance circuit connected to the detector to ensure linear rectification and having a balance circuit for adjusting the trigger level of an integrator; an integrator connected to the high impedance circuit; and a logarithmic operational amplifier connected to the integrator.
Claim 8
Dependent Claim
13 words
The apparatus of claim 6 wherein the display means is a digital voltmeter.
Claim 9
Dependent Claim
49 words
The apparatus of claim 7 including a command circuit for resetting the integrator and triggering the sample and hold circuit each time a new bond is made; said command circuit being controlled by a signal from the preamplifier of the channel receiving the electrical signal from the pick-up coil.
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) | 1977-08-05 | 1978-02-04 | 1978-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-05 | 1982-02-04 | 1982-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-05 | 1986-02-04 | 1986-08-06 | $7700.00 | Window Closed / Lapsed |