Patent US2438344A successfully refreshed from Google Patents.
US3907429A
Expired / Lapsed
US
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Method and device for detecting the velocity of droplets formed from a liquid stream
Assignee: International Business Machines Corp
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Filing: 1974-08-08
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Granted: 1975-09-23
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Expires: 1994-08-08
Abstract
Abstract Droplets from a liquid stream are directed between a pair of apertures and a light source, which is strobed at a selected frequency and directed toward the apertures. In one embodiment, the apertures are spaced less than a wavelength of the droplets apart and the light source is strobed at a frequency other than the frequency of the droplets. The time between when a first of the apertures is blocked by a droplet in the stream as indicated by the light being broken during a strobe and the time when a second of the apertures is blocked by another droplet when the light source is strobed is counted. This period of time will give the velocity of the droplets, and correction of the velocity is made, if the velocity of the droplets is not at the desired velocity, by changing the pressure, for example, of the manifold supplying the liquid stream until the desired velocity is obtained. In another embodiment, the apertures are spaced from each other a wavelength or an integral of the wavelength of the droplets, and the light source is strobed at the same frequency as the frequency at which the droplets are generated. The strobing frequency has its phase changed relative to the frequency of drop generation and the pressure of the stream changed until both of the apertures are blocked simultaneously. Any deviation from this indicates that the velocity of the droplets has changed and correction must be made.
Inventors
- 👤 Lawrence Kuhn
- 👤 Robert A Myers
- 👤 Keith S Pennington
- 👤 Bankim R Shah
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:38
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/07; B41J2/125; G; G01; G01P; G01P3/00; G01P3/64; G01P3/68
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
127 words
A device for detecting the velocity of droplets formed from a liquid stream including: means forming a pair of apertures spaced from each other a fixed distance related to the design wavelength of the droplets, said apertures being disposed on one side of the path of the droplets; light source means directed toward said apertures and disposed on the opposite side of the path of the droplets; means to strobe said light source means at a selected frequency related to the frequency of generation of the droplets; first means to detect when a droplet blocks each of said apertures; and second means to detect the velocity of the droplets in accordance with when each of said apertures is blocked and the selected frequency of said strobing means.
Claim 2
Independent Claim
127 words
A device for detecting the velocity of droplets formed from a liquid stream including: means forming a pair of apertures spaced from each other a fixed distance related to the design wavelength of the droplets, said apertures being disposed on one side of the path of the droplets; light source means directed toward said apertures and disposed on the opposite side of the path of the droplets; means to strobe said light source means at a selected frequency related to the frequency of generation of the droplets; first means to detect when a droplet blocks each of said apertures; and second means to detect the velocity of the droplets in accordance with when each of said apertures is blocked and the selected frequency of said strobing means.
Claim 3
Dependent Claim
48 words
The device according to claim 1 in which: said apertures are spaced from each other less than the design wavelength of the droplets; and said strobing means strobes said light source means at a frequency different than the frequency of generation of the droplets from the liquid stream.
Claim 4
Dependent Claim
58 words
The device according to claim 2 in which said second detecting means includes: means to count the time between when one of said apertures is blocked and when the other of said apertures is blocked; and means to utilize the output of said counting means to detect if the velocity of the droplets is at the desired velocity.
Claim 5
Dependent Claim
74 words
The device according to claim 1 in which: said apertures are spaced from each other a distance equal to the design wavelength of the droplets; said strobing means said light source means at the frequency at which the droplets are generated from the liquid stream; and said second detecting means includes means to detect when both of said apertures are blocked simultaneously to detect the design velocity of the droplets for the design wavelength.
Claim 6
Dependent Claim
53 words
The device according to claim 4 including: means to adjust the phases of the frequencies of said strobing means and the generation of the droplets relative to each other; and means to adjust the velocity of the droplets until both of said apertures are blocked simultaneously during strobing of said light source means.
Claim 7
Dependent Claim
78 words
The device according to claim 1 in which: said apertures are spaced from each other a distance equal to an integral of the design wavelength of the droplets; said strobing means strobes said light source means at the frequency at which the droplets are generated from the liquid stream; and said second detecting means includes means to detect when both of said apertures are blocked simultaneously to detect the design velocity of the droplets for the design wavelength.
Claim 8
Dependent Claim
53 words
The device according to claim 6 including: means to adjust the phases of the frequencies of said strobing means and the generation of the droplets relative to each other; and means to adjusT the velocity of the droplets until both of said apertures are blocked simultaneously during strobing of said light source means.
Claim 9
Independent Claim
95 words
A method of detecting the velocity of droplets formed from a liquid stream including: directing the droplets along a path between light source means and a pair of apertures; spacing the apertures from each other a fixed distance related to the design wavelength of the droplets; strobing the light source means at a selected frequency related to the frequency of generation of the droplets; detecting when a droplet blocks each of the apertures; and detecting the velocity of the droplets in accordance with when each of the apertures is blocked and the selected strobe frequency.
Claim 10
Independent Claim
95 words
A method of detecting the velocity of droplets formed from a liquid stream including: directing the droplets along a path between light source means and a pair of apertures; spacing the apertures from each other a fixed distance related to the design wavelength of the droplets; strobing the light source means at a selected frequency related to the frequency of generation of the droplets; detecting when a droplet blocks each of the apertures; and detecting the velocity of the droplets in accordance with when each of the apertures is blocked and the selected strobe frequency.
Claim 11
Dependent Claim
43 words
The method according to claim 8 including: spacing the apertures from each other less than the design wavelength of the droplets; and strobing the light source means at a frequency different than the frequency of generation of the droplets from the liquid stream.
Claim 12
Dependent Claim
45 words
The method according to claim 9 including: counting the time between when one of the apertures is blocked and when the other of the apertures is blocked; and utilizing the counted time to detect if the velocity of the droplets is at the desired velocity,
Claim 13
Dependent Claim
54 words
The method according to claim 8 including: spacing the apertures from each other the design wavelength of the droplets; strobing the light source means at the frequency of generation of the droplets from the liquid stream; and detecting when both of the apertures are simultaneously blocked to detect the desired velocity of the droplets.
Claim 14
Dependent Claim
49 words
The method according to claim 11 including: adjusting the phase of the frequencies of strobing the light source and generation of the droplets relative to each other; and adjusting the velocity of the droplets until both of the apertures are blocked simultaneously during strobing of the light source means.
Claim 15
Dependent Claim
57 words
The method according to claim 8 including: spacing the apertures from each other an integral of the design wavelength of the droplets; strobing the light source means at the frequency of generation of the droplets from the liquid stream; and detecting when both of the apertures are simultaneously blocked to detect the desired velocity of the droplets.
Claim 16
Dependent Claim
49 words
The method according to claim 13 including: adjusting the phase of the frequencies of strobing the light source and generation of the droplets relative to each other; and adjusting the velocity of the droplets until both of the apertures are blocked simultaneously during strobing of the light source means.
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) | 1978-09-22 | 1979-03-24 | 1979-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-22 | 1983-03-24 | 1983-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-22 | 1987-03-24 | 1987-09-23 | $7700.00 | Window Closed / Lapsed |