US4572103A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solder paste dispenser for SMD circuit boards
Assignee: Individual
•
Filing: 1984-12-20
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Granted: 1986-02-25
•
Expires: 2004-12-20
Abstract
Abstract A device for discretely controlled deposition of very small quantities of a viscous fluid at each of a succession of locations according to a digital X-Y-Z program. The primary application is for deposition of a slurry of small solder particles in a viscous fluid such as, for example, an organic acid RMA standard flux on a programmed succession of conductive pads or loci on or above the surface of a typical SMD circuit board. A pumping valve driven by pneumatic pressure effects a uniform deposition during the dwell time at each location. A free-piston syringe driven by pneumatic pressure supplies the slurry to a chamber within the pumping valve barrel which feed a small orifice (such as from a hypodermic needle). A pancake pneumatic cylinder controls the up-down motion of a rod acting as a piston to drive the predetermined uniform amount of slurry through the orifice on its down-stroke, the up-stroke aiding in the formation of a "fluid-sheer" cone of the deposited viscous material.
Inventors
- 👤 Harold J. Engel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 03:16
CPC Classifications
B; B23; B23K; B23K3/00; B23K3/06; B23K3/0607; B05; B05C; B05C5/00; B05C5/02; H; H05; H05K; H05K13/00; H05K13/04; H05K13/046; H05K13/0469; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/3465; H05K3/3485; H05K2203/00; H05K2203/01; H05K2203/0104; H05K2203/0126
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
144 words
A system for the deposition of a viscous fluid in small quantities at each of a plurality of X-Y-Z locations with respect to a surface, comprising: a dispensing device including an axially translating dispensing piston slideably located within a guiding passage ending in an orifice directed toward said surface; first means comprising a feed passage communicating laterally with said guiding passage, said feed passage having a greater cross-sectional area than that of said guiding passage; second means within said guiding passage comprising an enlargement of said guiding passage at the point of communication of said feed passage; third means for supplying said viscous fluid to said enlargement under pressure through said feed passage; and fourth means for causing said piston to translate through and beyond said enlargement to effect ejection of a discrete quantity of said viscous fluid from the orifice of said needle.
Claim 2
Independent Claim
144 words
A system for the deposition of a viscous fluid in small quantities at each of a plurality of X-Y-Z locations with respect to a surface, comprising: a dispensing device including an axially translating dispensing piston slideably located within a guiding passage ending in an orifice directed toward said surface; first means comprising a feed passage communicating laterally with said guiding passage, said feed passage having a greater cross-sectional area than that of said guiding passage; second means within said guiding passage comprising an enlargement of said guiding passage at the point of communication of said feed passage; third means for supplying said viscous fluid to said enlargement under pressure through said feed passage; and fourth means for causing said piston to translate through and beyond said enlargement to effect ejection of a discrete quantity of said viscous fluid from the orifice of said needle.
Claim 3
Dependent Claim
43 words
A system according to claim 1 in which said orifice is at the end of a hypodermic type needle in communication with the end of said guiding passage nearest the end of said piston at its maximum translation through and beyond said enlargement.
Claim 4
Dependent Claim
20 words
A system according to claim 2 in which said viscous fluid is a slurry of soldering flux and solder particles.
Claim 5
Dependent Claim
42 words
A system according to claim 3 in which fifth means are included for programming X-Y location and the operation of said fourth means to control said dispensing device to make depositions at each of a number of predetermined locations on said surface.
Claim 6
Dependent Claim
20 words
A system according to claim 1 in which said viscous fluid is a slurry of soldering flux and solder particles.
Claim 7
Dependent Claim
42 words
A system according to claim 5 in which fifth means are included for programming X-Y location and the operation of said fourth means to control said dispensing device to make depositions at each of a number of predetermined locations on said surface.
Claim 8
Dependent Claim
41 words
A system according to claim 6 in which said fifth means comprises a digital computer and X, Y, Z coordinate servomechanisms responsive to said computer to effect successive location of said dispensing device according to a program associated with said computer.
Claim 9
Dependent Claim
42 words
A system according to claim 1 in which fifth means are included for programming X-Y location and the operation of said fourth means to control said dispensing device to make depositions at each of a number of predetermined locations on said surface.
Claim 10
Dependent Claim
41 words
A system according to claim 8 in which said fifth means comprises a digital computer and X,Y, and Z coordinate servomechanisms responsive to said computer to effect successive location of said dispensing device according to a program associated with said computer.
Claim 11
Dependent Claim
47 words
A system according to claim 8 in which said fourth means comprises a double-acting air cylinder connected to translate said dispensing piston "up" or "down" in accordance with activation of a corresponding pressurized air feed affecting a corresponding side of the piston of said double-acting air cylinder.
Claim 12
Dependent Claim
35 words
A system according to claim 10 further including a pneumatic controller responsive to said fifth means for applying air to a side of said dispensing piston corresponding to the programmed signal from said fifth means.
Claim 13
Dependent Claim
54 words
A system according to claim 1 in which said enlargement in said guiding passage is generally annular in shape, having a cross-sectional area greater than the cross-sectional area of said guiding passage and having a dimension along the axial centerline of said guiding passage at least equal to the diameter of said feed passage.
Claim 14
Dependent Claim
48 words
A system according to claim 1 in which said enlargement in said guiding passage is annular in shape having a cross-sectional diameter greater than that of said guiding passage and a dimension along the axial centerline of said guiding passage equal to the diameter of said feed passage.
Claim 15
Dependent Claim
50 words
A system according to claim 1 in which said third means comprises a syringe having an output connection and a free piston within, said viscous fluid being emplaced between said piston and said output connection, and a source of air under pressure applied to the other side of said piston.
Claim 16
Dependent Claim
47 words
A system according to claim 1 in which said fourth means comprises a double-acting air cylinder connected to translate said dispensing piston "up" or "down" in accordance with activation of a corresponding pressurized air feed affecting a corresponding side of the piston of said double-acting air cylinder.
Claim 17
Dependent Claim
31 words
A system according to claim 15 in which said double-acting air cylinder is a pancake cylinder in which the piston thereof is a deflectable diaphragm, center connected to said dispensing piston.
Claim 18
Dependent Claim
50 words
A system according to claim 15 in which said third means comprises a syringe having an output connection and a free piston within, said viscous fluid being emplaced between said piston and said output connection, and a source of air under pressure applied to the other side of said piston.
Claim 19
Dependent Claim
15 words
A system according to claim 1 in which said viscous fluid is homogeneous viscous fluid.
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) | 1989-02-24 | 1989-08-26 | 1990-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-02-24 | 1993-08-26 | 1994-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-02-24 | 1997-08-26 | 1998-02-25 | $7700.00 | Window Closed / Lapsed |