US3893028A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Probe multimeter with display inverting means
Assignee: HP Inc
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Filing: 1973-10-16
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Granted: 1975-07-01
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Expires: 1993-10-16
Abstract
Abstract A handheld multimeter for measuring electrical parameters is provided with a solid state display and associated means for inverting the displayed measurement result.
Inventors
- 👤 Paul F Febvre
- 👤 Virgil Lee Laing
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 01:04
CPC Classifications
G; G01; G01R; G01R19/00; G01R19/145; G01R1/00; G01R1/02; G01R1/06; G01R1/067; G01R1/06788; G01R1/04; G01R15/00; G01R15/12; G01R15/125; G01R19/25; G01R19/2503
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
137 words
Electrical signal measuring apparatus comprising: display means for visually displaying character information indicative of a measurement result, said display means comprising one or more character positions; switch means for selecting either an upright or an inverted display mode of operation; first logic means coupled to said display means and switch means, said first logic means being responsive to selection of the inverted display mode of operation for reflecting upright character information associated with each of said character positions about a central one of said character positions; and second logic means coupled to said display means, switch means, and first logic means, said second logic means being responsive to selection of the inverted display mode of operation for reflecting upright character information associated with each of said character positions about a central portion of each respective character position.
Claim 2
Dependent Claim
137 words
Electrical signal measuring apparatus comprising: display means for visually displaying character information indicative of a measurement result, said display means comprising one or more character positions; switch means for selecting either an upright or an inverted display mode of operation; first logic means coupled to said display means and switch means, said first logic means being responsive to selection of the inverted display mode of operation for reflecting upright character information associated with each of said character positions about a central one of said character positions; and second logic means coupled to said display means, switch means, and first logic means, said second logic means being responsive to selection of the inverted display mode of operation for reflecting upright character information associated with each of said character positions about a central portion of each respective character position.
Claim 3
Dependent Claim
20 words
Electrical signal measuring apparatus as in claim 1 wherein said first logic means comprises a first group of read-only memories.
Claim 4
Dependent Claim
53 words
Electrical signal measuring apparatus as in claim 2 wherein said display means comprises a seven-segment display at each character position, and wherein said second logic means comprises a second group of read-only memories for reflecting segment information associated with each of said character positions about a central segment of each respective character position.
Claim 5
Dependent Claim
131 words
Circuitry for inverting a character message visually displayed within an electronic display which includes one or more character positions, said circuitry comprising: switch means for selecting either an upright or an inverted display mode of operation; first logic means coupled to said display and switch means, said first logic mEans being responsive to selection of the inverted display mode of operation for reflecting upright character information associated with each of said character positions about a central one of said character positions; and second logic means coupled to said display, switch means, and first logic means, said second logic means being responsive to selection of the inverted display mode of operation for reflecting upright character information associated with each of said character positions about a central portion of each respective character position.
Claim 6
Dependent Claim
131 words
Circuitry for inverting a character message visually displayed within an electronic display which includes one or more character positions, said circuitry comprising: switch means for selecting either an upright or an inverted display mode of operation; first logic means coupled to said display and switch means, said first logic mEans being responsive to selection of the inverted display mode of operation for reflecting upright character information associated with each of said character positions about a central one of said character positions; and second logic means coupled to said display, switch means, and first logic means, said second logic means being responsive to selection of the inverted display mode of operation for reflecting upright character information associated with each of said character positions about a central portion of each respective character position.
Claim 7
Dependent Claim
17 words
Circuitry as in claim 4 wherein said first logic means comprises a first group of read-only memories.
Claim 8
Dependent Claim
52 words
Circuitry as in claim 5 wherein characters are formed by means of a seven-segment display at each character position, and wherein said second logic means comprises a second group of read-only memories for reflecting segment information associated with each of said character positions about a central segment of each respective character position.
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) | 1978-06-30 | 1978-12-30 | 1979-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-30 | 1982-12-30 | 1983-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-30 | 1986-12-30 | 1987-07-01 | $7700.00 | Window Closed / Lapsed |