Patent US3653253A successfully refreshed from Google Patents.
US3653253A
Expired / Lapsed
US
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Aerosol mass concentration spectrometer
Assignee: THERMO SYSTEMS Inc
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Filing: 1970-01-05
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Granted: 1972-04-04
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Expires: 1990-01-05
Abstract
Abstract An apparatus and method for determining particle or aerosol mass concentration distribution using a particle sensing element, as a piezoelectric crystal, for collecting particles to increase the mass of the element. The particles are force deposited on the sensing element. The amount of force is sequentially changed to alter the critical particle size deposited on the sensing element. The mass of the particles accumulated on the sensing element during each force period provides information of the particle mass concentration. The difference between particle mass concentration, at two successive values of critical particle sizes, provides data relative to particle mass concentration distribution.
Inventors
- 👤 John G Olin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:24
CPC Classifications
G; G01; G01N; G01N29/00; G01N29/02; G01N29/036; G01N5/00; G01N2291/00; G01N2291/02; G01N2291/025; G01N2291/0256
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
125 words
An apparatus for measurement of particle mass concentration distribution of an aerosol comprising: particle sensing means having a resonant frequency and a particle collection surface for collecting particles of an aerosol, means to drive and sense the resonant frequency of the sensing means, means imparting a force field on the particles for forcing particles into engagement with the particle collection surface, means for varying the amount of said force, whereby the variation in the critical size of particles accumulated on the particle collection surface is related to the variance of the force, and monitor means to read the sensed resonant frequency providing information as to the changes in resonant frequency of the sensing means at each force variation to determine the particle mass concentration distribution.
Claim 2
Independent Claim
125 words
An apparatus for measurement of particle mass concentration distribution of an aerosol comprising: particle sensing means having a resonant frequency and a particle collection surface for collecting particles of an aerosol, means to drive and sense the resonant frequency of the sensing means, means imparting a force field on the particles for forcing particles into engagement with the particle collection surface, means for varying the amount of said force, whereby the variation in the critical size of particles accumulated on the particle collection surface is related to the variance of the force, and monitor means to read the sensed resonant frequency providing information as to the changes in resonant frequency of the sensing means at each force variation to determine the particle mass concentration distribution.
Claim 3
Dependent Claim
49 words
The apparatus of claim 1 wherein: the means for forcing the particles into engagement with the particle collection surface is an impactor having an inlet orifice to direct particles toward the surface and vacuum pump means connected to the impactor operable to draw air and particles through the impactor.
Claim 4
Dependent Claim
50 words
The apparatus of claim 2 wherein: the means to vary the amount of force is a valve means located between the impactor and pump, means to control the flow rate of air and particles, for the valve means to regulate the flow rate of air and particles through the orifice.
Claim 5
Dependent Claim
40 words
The apparatus of claim 2 wherein: the means to vary the amount of force is a control means to vary the speed of operation of the pump means to change the flow rate of air and particles through the orifice.
Claim 6
Dependent Claim
35 words
The apparatus of claim 2 wherein: the means to vary the amount of force comprise means to change the size of the orifice to alter the velocity of air and particles moving through the orifice.
Claim 7
Dependent Claim
32 words
The apparatus of claim 5 wherein: the means to change the size of the orifice comprises a slide, and motor means to move the slide to change the size of the orifice.
Claim 8
Independent Claim
150 words
An apparatus for measurement of particle mass concentration distribution of an aerosol comprising: particle sensing means including a piezoelectric crystal having a sensitive particle collecting surface for collecting particles of an aerosol, means for forcing particles into engagement with the particle collection surface, means for varying the amount of said force whereby variation in the critical size of particles accumulated on the surface is related to the variance of the force, said means to sense the mass of particles deposited on the surface including means to sense the resonant frequency of the crystal, and monitor means operable to read the changes in the resonant frequency of the crystal due to changes in the total mass of particles added to said surface in response to changes in the amount of force used to deposit particles onto said surface at each force variation providing information to determine the particle mass concentration distribution.
Claim 9
Independent Claim
150 words
An apparatus for measurement of particle mass concentration distribution of an aerosol comprising: particle sensing means including a piezoelectric crystal having a sensitive particle collecting surface for collecting particles of an aerosol, means for forcing particles into engagement with the particle collection surface, means for varying the amount of said force whereby variation in the critical size of particles accumulated on the surface is related to the variance of the force, said means to sense the mass of particles deposited on the surface including means to sense the resonant frequency of the crystal, and monitor means operable to read the changes in the resonant frequency of the crystal due to changes in the total mass of particles added to said surface in response to changes in the amount of force used to deposit particles onto said surface at each force variation providing information to determine the particle mass concentration distribution.
Claim 10
Dependent Claim
49 words
The apparatus of claim 7 wherein: the means for forcing the particles into engagement with the particle collection surface is an impactor having an inlet orifice to direct particles toward the surface and vacuum pump means connected to the impactor operable to draw air and particles through the impactor.
Claim 11
Dependent Claim
52 words
The apparatus of claim 8 wherein: the means to vary the amount of force is a valve means located between the impactor and pump means to control the flow of air and particles, and control means for the valve means to regulate the flow rate of air and particles through the orifice.
Claim 12
Dependent Claim
40 words
The apparatus of claim 8 wherein: the means to vary the amount of force is a control means to vary the speed of operation of the pump means To change the flow rate of air and particles through the orifice.
Claim 13
Dependent Claim
35 words
The apparatus of claim 8 wherein: the means to vary the amount of force comprise means to change the size of the orifice to alter the velocity of air and particles moving through the orifice.
Claim 14
Dependent Claim
32 words
The apparatus of claim 11 wherein: the means to change the size of the orifice comprises a slide, and motor means to move the slide to change the size of the orifice.
Claim 15
Dependent Claim
138 words
The apparatus of claim 7 wherein: the means for forcing the particles into engagement with the particle collection surface is an impactor having a first chamber and a second chamber spaced from the first chamber, passage means connecting the first chamber with the second chamber, first means for introducing particles and air into the first chamber, second means for introducing clean air into the first chamber, said particle collection surface located in axial alignment with the discharge end of the passage means, and means to withdraw air from the second chamber, whereby the particles introduced into the first chamber are drawn through the passage means and an annular sheath of clean air surrounds the particles in the passage means, said particles as they move in the passage means being surrounded with a moving annular sheath of clean air.
Claim 16
Dependent Claim
38 words
The apparatus of claim 13 wherein: the first means is a tubular member extended into the first chamber in axial alignment with the passage means, said tubular member having a sonic orifice for the particles and ambient air.
Claim 17
Dependent Claim
54 words
The apparatus of claim 13 wherein: the means to vary the amount of force is a valve located between the second chamber and means to withdraw air from the second chamber, and control means for the valve to regulate the flow rate of ambient air and particles and clean air through the passage means.
Claim 18
Independent Claim
232 words
An apparatus for measurement of particle mass concentration distribution comprising: particle sensing means having a particle collection surface for collecting particles, means to sense the mass of particles deposited on the particle collection surface, means for forcing particles into engagement with the particle collection surface, means for varying the amount of said force, whereby a variation in the critical size of particles accumulated on the surface is related to the variance of the force, and monitor means to read the sensed mass of particles at each force variation providing information to determine the particle mass concentration distribution, said means for forcing the particle into engagement with the particle collection surface is an impactor having a first chamber and a second chamber spaced from the first chamber, passage means connecting the first chamber with the second chamber, first means for introducing particles and air into the first chamber, second means for introducing clean air into the first chamber, said particle collection surface located in the second chamber in axial alignment with the discharge end of the passage means, and means to withdrawn air from the second chamber, whereby the particles introduced into the first chamber are drawn through the passage means and an annular sheath of clean air surrounds the particles in the passage means, said particles as they move in the passage means being surrounded with a moving sheath of clean air.
Claim 19
Independent Claim
232 words
An apparatus for measurement of particle mass concentration distribution comprising: particle sensing means having a particle collection surface for collecting particles, means to sense the mass of particles deposited on the particle collection surface, means for forcing particles into engagement with the particle collection surface, means for varying the amount of said force, whereby a variation in the critical size of particles accumulated on the surface is related to the variance of the force, and monitor means to read the sensed mass of particles at each force variation providing information to determine the particle mass concentration distribution, said means for forcing the particle into engagement with the particle collection surface is an impactor having a first chamber and a second chamber spaced from the first chamber, passage means connecting the first chamber with the second chamber, first means for introducing particles and air into the first chamber, second means for introducing clean air into the first chamber, said particle collection surface located in the second chamber in axial alignment with the discharge end of the passage means, and means to withdrawn air from the second chamber, whereby the particles introduced into the first chamber are drawn through the passage means and an annular sheath of clean air surrounds the particles in the passage means, said particles as they move in the passage means being surrounded with a moving sheath of clean air.
Claim 20
Dependent Claim
38 words
The apparatus of claim 16 wherein: the first means is a tubular member extended into the first chamber in axial alignment with the passage means, said tubular member having a sonic orifice for the particles and ambient air.
Claim 21
Dependent Claim
54 words
The apparatus of claim 16 wherein: the means to vary the amount of force is a valve located between the second chamber and means to withdraw air from the second chamber, and control means for the valve to regulate the flow rate of ambient air and particles and clean air through the passage means.
Claim 22
Independent Claim
112 words
A method of measurement of particle mass concentration distribution of an aerosol comprising: force depositing particles of an aerosol directly onto a sensitive particle Collection surface of a particle sensing means having a resonant frequency with a force sufficient to place the particles in contact with the particle collection surface, driving the particle sensing means at its resonant frequency, sequentially varying the force acting on the particles to change the critical particle size deposited on the surface, and monitoring the resonant frequency change of the particle sensing means during the depositing of particles on the particle collection surface of each force variation to provide information to determine the particle mass concentration distribution.
Claim 23
Independent Claim
112 words
A method of measurement of particle mass concentration distribution of an aerosol comprising: force depositing particles of an aerosol directly onto a sensitive particle Collection surface of a particle sensing means having a resonant frequency with a force sufficient to place the particles in contact with the particle collection surface, driving the particle sensing means at its resonant frequency, sequentially varying the force acting on the particles to change the critical particle size deposited on the surface, and monitoring the resonant frequency change of the particle sensing means during the depositing of particles on the particle collection surface of each force variation to provide information to determine the particle mass concentration distribution.
Claim 24
Dependent Claim
21 words
The method of claim 19 wherein: the force is sequentially increased to decrease the critical particle size deposited on the surface.
Claim 25
Dependent Claim
44 words
The method of claim 19 wherein: the particles are force deposited with a jet of air directed toward the sensitive particle collection surface and varying the velocity of the jet of air to change the critical particle size deposited on the particle collection surface.
Claim 26
Dependent Claim
27 words
The method of claim 19 wherein: the particles are enclosed in a sheath of clean air during the time they are directed toward the particle collection surface.
Claim 27
Dependent Claim
61 words
The method of claim 19 wherein: the particles are force deposited with a jet of air directed toward the particle collection surface, and surrounding said jet of air with a sheath of clean air to confine and accelerate the particles, and varying said velocity of the jet of air to change the critical particle size deposited on the particle collection surface.
Claim 28
Dependent Claim
21 words
The method of claim 19 wherein: the force is sequentially decreased to increase the critical particle size deposited on the surface.
Claim 29
Independent Claim
95 words
A method of measurement of particle mass concentration distribution of an aerosol comprising: force depositing particles of an aerosol directly onto a sensitive electrode of a piezoelectric crystal, sequentially varying the force acting on the particles to change the critical particle size deposited on the electrode, driving the crystal and sensing the resonant frequency of the crystal at each force to provide information on the particle mass concentration at each force, whereby the difference in the particle mass concentration between two successive values of critical particle sizes provides data relative to particle mass concentration distribution.
Claim 30
Independent Claim
95 words
A method of measurement of particle mass concentration distribution of an aerosol comprising: force depositing particles of an aerosol directly onto a sensitive electrode of a piezoelectric crystal, sequentially varying the force acting on the particles to change the critical particle size deposited on the electrode, driving the crystal and sensing the resonant frequency of the crystal at each force to provide information on the particle mass concentration at each force, whereby the difference in the particle mass concentration between two successive values of critical particle sizes provides data relative to particle mass concentration distribution.
Claim 31
Dependent Claim
21 words
The method of claim 25 wherein: the force is sequentially increased to decrease the critical particle size deposited on the electrode.
Claim 32
Dependent Claim
42 words
The method of claim 25 wherein: the particles are force deposited on the electrode with a jet of air directed toward the electrode and varying the velocity of the jet of air to change the critical particle size deposited on the electrode.
Claim 33
Dependent Claim
25 words
The method of claim 25 wherein: the particles are enclosed in a sheath of clean air during the time they are directed toward the electrode.
Claim 34
Dependent Claim
59 words
The method of claim 25 wherein: the particles are force deposited with a jet of air directed toward the electrode, and surrounding said jet of air with a sheath of clean air to confine and accelerate the particles, and varying said velocity of the jet of air to change the critical particle size deposited on the particle collection surface.
Claim 35
Dependent Claim
20 words
The method of claim 25 wherein: the force is sequentially decreased to increase the particle size deposited on the electrode.
Claim 36
Independent Claim
144 words
An apparatus for measurement of particle mass concentration distribution of an aerosol comprising: particle sensing means having at least a first sensing device and a second sensing device, each of said sensing devices having a resonant frequency and a particle collection surface for collecting particles of an aerosol, means to drive and sense the resonant frequency of the sensing devices, means imparting a force field on the particles for forcing particles into contact with at least one of the particle collection surfaces, means for varying the amount of said force, whereby variation in the critical size of particles accumulated on the particle collection surfaCe is related to the variance of the force, and monitor means to read the sensed resonant frequency providing information as to changes in resonant frequency of the sensing devices at each force variation to determine the particle mass concentration distribution.
Claim 37
Independent Claim
144 words
An apparatus for measurement of particle mass concentration distribution of an aerosol comprising: particle sensing means having at least a first sensing device and a second sensing device, each of said sensing devices having a resonant frequency and a particle collection surface for collecting particles of an aerosol, means to drive and sense the resonant frequency of the sensing devices, means imparting a force field on the particles for forcing particles into contact with at least one of the particle collection surfaces, means for varying the amount of said force, whereby variation in the critical size of particles accumulated on the particle collection surfaCe is related to the variance of the force, and monitor means to read the sensed resonant frequency providing information as to changes in resonant frequency of the sensing devices at each force variation to determine the particle mass concentration distribution.
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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) | 1975-04-04 | 1975-10-04 | 1976-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-04 | 1979-10-04 | 1980-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-04 | 1983-10-04 | 1984-04-04 | $7700.00 | Window Closed / Lapsed |