Patent US3920985A successfully refreshed from Google Patents.
US3920985A
Expired / Lapsed
US
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Means for effecting improvements to mass spectrometers and mass filters
Assignee: Unisearch Ltd
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Filing: 1974-01-28
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Granted: 1975-11-18
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Expires: 1994-01-28
Abstract
Abstract A mass or energy filter or spectrometer having a known electrode configuration such as quadrupole cylindrical, monopole cylindrical or hyperboloidal wherein the electrodes are energised by a periodic or quasi-periodic time varying electrical potential the waveform of which is significantly different from a sinusoid and incorporates a zeroth harmonic term in its Fourier series. It is preferred that the waveform should be either rectangular in character or trapezoidal in character and that means should be provided for varying the duty cycle of the waveform.
Inventors
- 👤 John Barry Hiller
- 👤 John Alan Richards
- 👤 Richard Meredyth Huey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:02
CPC Classifications
H; H01; H01J; H01J49/00; H01J49/26; H01J49/34; H01J49/42; H01J49/4205; H01J49/421; H01J49/4215
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
87 words
In a mass spectrometer of the quadrupole type, the improvement comprising a single generating means for generating a single periodic time varying electrical output potential having both A.C. components and a D.C. component, said potential having a segmented waveform formed by a repetitive sequence of discrete substantially linear segments each being composed of at least one substantially linearly varying function of time, and said generating means being operatively coupled to said mass spectrometer such that said potential may Be applied to analyzing electrodes of said mass spectrometer.
Claim 2
Dependent Claim
87 words
In a mass spectrometer of the quadrupole type, the improvement comprising a single generating means for generating a single periodic time varying electrical output potential having both A.C. components and a D.C. component, said potential having a segmented waveform formed by a repetitive sequence of discrete substantially linear segments each being composed of at least one substantially linearly varying function of time, and said generating means being operatively coupled to said mass spectrometer such that said potential may Be applied to analyzing electrodes of said mass spectrometer.
Claim 3
Dependent Claim
28 words
The improved apparatus of claim 1 wherein said waveform is substantially rectangular and said generating means further comprises a means for varying the duty cycle of said waveform.
Claim 4
Dependent Claim
27 words
The improved apparatus of claim 1 wherein said waveform is substantially trapozoidal and said generating means further comprises means for varying the duty cycle of said waveform.
Claim 5
Dependent Claim
29 words
The improved mass spectrometer of claim 1 wherein said generating means further comprises means for varying the ratio of the amplitude of the D.C. component to the A.C. components.
Claim 6
Dependent Claim
27 words
The improved mass spectrometer of claim 1 wherein said waveform is quadrilateral and said generating means further comprises means for varying the duty cycle of the waveform.
Claim 7
Dependent Claim
33 words
The system of claim 1 further comprising means for varying the amplitude of said waveform at a relatively slow rate whereby the mass-response of the mass spectrometer is scanned over a desired range.
Claim 8
Dependent Claim
34 words
The system of claim 1 further comprising means for varying the repetition rate of said waveform at a relatively slow rate whereby the mass-response of the mass spectrometer is scanned over a desired range.
Claim 9
Dependent Claim
67 words
The improvement of claim 1 wherein said generating means comprises a source of substantially linear waveform components, a switch means operatively connecting said source to said analyzing electrodes for supplying a selected waveform to said analyzing electrodes of said mass spectrometer, and a source of clock pulses operatively connected to said switch for activating said switch for varying the waveform which is applied to said analyzing electrodes.
Claim 10
Dependent Claim
102 words
A mass spectrometer of the quadrupole type, comprising: a single means for generating a single periodic time varying electrical output potential having both A.C. components and a D.C. component, said potential having a segmented waveform formed by a repetitive sequence of discrete segments each being composed of at least one substantially linearly varying function of time and said means being operatively coupled to said mass spectrometer such that said potential may be applied to analyzing electrodes of said mass spectrometer; auxiliary analyzing electrodes positioned between an ion source and said analyzing electrodes; and means for energizing said auxiliary analyzing electrodes, connected thereto.
Claim 11
Dependent Claim
102 words
A mass spectrometer of the quadrupole type, comprising: a single means for generating a single periodic time varying electrical output potential having both A.C. components and a D.C. component, said potential having a segmented waveform formed by a repetitive sequence of discrete segments each being composed of at least one substantially linearly varying function of time and said means being operatively coupled to said mass spectrometer such that said potential may be applied to analyzing electrodes of said mass spectrometer; auxiliary analyzing electrodes positioned between an ion source and said analyzing electrodes; and means for energizing said auxiliary analyzing electrodes, connected thereto.
Claim 12
Dependent Claim
33 words
The system of claim 9 further comprising means for varying the amplitude of said waveform at a relatively slow rate whereby the mass-response of the mass spectrometer is scanned over a desired range.
Claim 13
Dependent Claim
34 words
The system of claim 9 further comprising means for varying the repitition rate of said waveform at a relatively slow rate whereby the mass-response of the mass spectrometer is scanned over a desired range.
Claim 14
Dependent Claim
95 words
In a mass spectrometer of the quadrupole type, the improvement comprising means for generating a single time varying electrical output potential having a segmented waveform, said potential being formed by a repetitive sequence of discrete segments each being composed of at least one substantially exponentially varying function of time expressed as: a + be (c jd) t - Infinity <t< Infinity where a, b, c, d are real constants, c >0 and said means being operatively coupled to said mass spectrometer such that said potential may be applied to analyzing electrodes of said mass spectrometer.
Claim 15
Dependent Claim
95 words
In a mass spectrometer of the quadrupole type, the improvement comprising means for generating a single time varying electrical output potential having a segmented waveform, said potential being formed by a repetitive sequence of discrete segments each being composed of at least one substantially exponentially varying function of time expressed as: a + be (c jd) t - Infinity <t< Infinity where a, b, c, d are real constants, c >0 and said means being operatively coupled to said mass spectrometer such that said potential may be applied to analyzing electrodes of said mass spectrometer.
Claim 16
Dependent Claim
27 words
The improved apparatus of claim 12 wherein said waveform is substantially rectangular and said generating means further comprises means for varying the duty cycle of said waveform.
Claim 17
Dependent Claim
28 words
The improved apparatus of claim 12 wherein said waveform is substantially trapezoidal and said generating means further comprises a means for varying the duty cycle of said waveform.
Claim 18
Dependent Claim
29 words
The improved mass spectrometer of claim 12 wherein said generating means further comprises means for varying the ratio of the amplitude of the constant a to thE other terms.
Claim 19
Dependent Claim
28 words
The improved mass spectrometer of claim 12 wherein said waveform is a quadrilateral and said generating means further comprises means for varying the duty cycle of the waveform.
Claim 20
Dependent Claim
24 words
The system of claim 12 further comprising auxiliary analyzing electrodes operatively coupled to said means for generating a single time varying electrical output potential.
Claim 21
Dependent Claim
33 words
The system of claim 12 further comprising means for varying the amplitude of said waveform at a relatively slow rate whereby the mass-response of the mass spectrometer is scanned over a desired range.
Claim 22
Dependent Claim
34 words
The system of claim 12 further comprising means for varying the repetition rate of said waveform at a relatively slow rate whereby the mass-response of the mass spectrometer is scanned over a desired range.
References Cited (Backward Citations)
US3413463A
Cited
US3735287A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-17 | 1979-05-19 | 1979-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-17 | 1983-05-19 | 1983-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-17 | 1987-05-19 | 1987-11-18 | $7700.00 | Window Closed / Lapsed |