Patent US4794259A successfully refreshed from Google Patents.
US4794259A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Charged particle collection
Assignee: Welding Institute England
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Filing: 1987-03-19
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Granted: 1988-12-27
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Expires: 2007-03-19
Abstract
Abstract A charged particle collector assembly, particularly for use with an electron beam gun, is described. The assembly comprises a reflection member onto which electrons impinge in use, the reflection member being adapted substantially to absorb particles of one polarity and substantially to reflect particles of the other polarity. A sensor or collector is positioned to receive particles reflected from the reflection member and to generate a corresponding output signal.
Inventors
- 👤 Allan Sanderson
- 👤 Colin N. Ribton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:05
CPC Classifications
B; B23; B23K; B23K15/00; B23K15/0013; H; H01; H01J; H01J37/00; H01J37/02; H01J37/244; H01J37/30; H01J37/304; H01J2237/00; H01J2237/244; H01J2237/2446; H01J2237/24465; H01J2237/24475; H01J2237/2449; H01J2237/245; H01J2237/24507
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
63 words
A charged particle collector assembly comprising a reflection member onto which charged particles impinge in use, said reflection member substantially absorbing particles of one polarity and substantially reflecting articles of the other polarity; and a sensor positioned to receive said reflected particles only after said particles have impinged on and been reflected from said reflection member and to generate a corresponding output signal.
Claim 2
Dependent Claim
63 words
A charged particle collector assembly comprising a reflection member onto which charged particles impinge in use, said reflection member substantially absorbing particles of one polarity and substantially reflecting articles of the other polarity; and a sensor positioned to receive said reflected particles only after said particles have impinged on and been reflected from said reflection member and to generate a corresponding output signal.
Claim 3
Dependent Claim
21 words
An assembly according to claim 1, further comprising a shield arranged to prevent charged particles from directly impinging on said sensor.
Claim 4
Dependent Claim
27 words
An assembly according to claim 1, further comprising means for applying a potential to said reflection member having the same polarity as said particles to be reflected.
Claim 5
Dependent Claim
21 words
An assembly according to claim 1, wherein said reflector defines a concave surface onto which said beam of charged particles impinges.
Claim 6
Dependent Claim
21 words
An assembly according to claim 1, wherein said reflection member is substantially annular and formed from a number of subsidiary members.
Claim 7
Dependent Claim
19 words
A method according to claim 1 wherein said charged particles impinging on said reflection member are backscattered charged particles.
Claim 8
Dependent Claim
74 words
In combination, at least two charged particle collector assemblies, each said assembly comprising a reflection member onto which charged particles impinge in use, said reflection member absorbing particles of one polarity and substantially reflecting particles of the other polarity; and a sensor positioned to receive said reflected particles only after said particles have impinged on and been reflected from said reflection member and to generate a corresponding output signal, wherein said assemblies are nested.
Claim 9
Dependent Claim
74 words
In combination, at least two charged particle collector assemblies, each said assembly comprising a reflection member onto which charged particles impinge in use, said reflection member absorbing particles of one polarity and substantially reflecting particles of the other polarity; and a sensor positioned to receive said reflected particles only after said particles have impinged on and been reflected from said reflection member and to generate a corresponding output signal, wherein said assemblies are nested.
Claim 10
Dependent Claim
81 words
In combination, at least two charged particle collector assemblies, each said assembly comprising a reflection member onto which charged particles impinge in use, said reflection member substantially absorbing particles of one polarity and substantially reflecting particles of the other polarity; and a sensor positioned to receive particles reflected from said reflection member and to generate a corresponding output signal, wherein said assemblies are axially aligned and wherein said sensor of an upstream assembly constitutes a reflector for the adjacent downstream assembly.
Claim 11
Dependent Claim
81 words
In combination, at least two charged particle collector assemblies, each said assembly comprising a reflection member onto which charged particles impinge in use, said reflection member substantially absorbing particles of one polarity and substantially reflecting particles of the other polarity; and a sensor positioned to receive particles reflected from said reflection member and to generate a corresponding output signal, wherein said assemblies are axially aligned and wherein said sensor of an upstream assembly constitutes a reflector for the adjacent downstream assembly.
Claim 12
Dependent Claim
71 words
Charged particle beam welding apparatus incorporating at least one charged particle collector assembly comprising a reflection member onto which charged particles impinge in use, said reflection member substantially absorbing particles of one polarity and substantially reflecting particles of the other polarity; and a sensor positioned to receive said reflected particles only after said particles have impinged on and been reflected from said reflection member and to generate a corresponding output signal.
Claim 13
Dependent Claim
71 words
Charged particle beam welding apparatus incorporating at least one charged particle collector assembly comprising a reflection member onto which charged particles impinge in use, said reflection member substantially absorbing particles of one polarity and substantially reflecting particles of the other polarity; and a sensor positioned to receive said reflected particles only after said particles have impinged on and been reflected from said reflection member and to generate a corresponding output signal.
Claim 14
Dependent Claim
19 words
A method as defined by claim 9 wherein the charged particles scattered by said workpiece are backscattered charged particles.
Claim 15
Independent Claim
148 words
A method of controlling the impingement of a beam of charged particles on a workpiece having an elongate feature, said method comprising causing relative movement between said beam and said workpiece whereby said beam impinges on successive primary positions along said elongate feature; causing said beam periodically to scan across said elongate feature at an advanced position relatively to said corresponding primary position; collecting charged particles scattered by said workpiece during the scanning step in a charged particle collector assembly comprising a reflection member onto which charged particles impinge in use, said reflection member substantially absorbing particles of one polarity and substantially reflecting particles of the other polarity; and a sensor positioned to receive reflected particles only after said particles have impinged on and been reflected frolm said reflection member and to generate a corresponding output signal; and monitoring said signal generated by said sensor of said assembly.
Claim 16
Independent Claim
148 words
A method of controlling the impingement of a beam of charged particles on a workpiece having an elongate feature, said method comprising causing relative movement between said beam and said workpiece whereby said beam impinges on successive primary positions along said elongate feature; causing said beam periodically to scan across said elongate feature at an advanced position relatively to said corresponding primary position; collecting charged particles scattered by said workpiece during the scanning step in a charged particle collector assembly comprising a reflection member onto which charged particles impinge in use, said reflection member substantially absorbing particles of one polarity and substantially reflecting particles of the other polarity; and a sensor positioned to receive reflected particles only after said particles have impinged on and been reflected frolm said reflection member and to generate a corresponding output signal; and monitoring said signal generated by said sensor of said assembly.
Claim 17
Dependent Claim
27 words
A method according to claim 11, further comprising controlling said relative movement between said beam and said workpiece in accordance with said signal generated by said sensor.
Claim 18
Dependent Claim
18 words
A method according to claim 11, wherein the power of said beam is reduced during said scanning step.
Claim 19
Dependent Claim
23 words
A method according to claim 11, further comprising causing said beam of charged particles to perform a welding operation at each primary position.
Claim 20
Dependent Claim
19 words
A method as defined by claim 11 wherein the charged particles scattered by said workpiece are backscattered charged particles.
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) | 1991-12-27 | 1992-06-27 | 1992-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-12-27 | 1996-06-27 | 1996-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-12-27 | 2000-06-27 | 2000-12-27 | $7700.00 | Window Closed / Lapsed |