US3621158A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical switching apparatus
Assignee: Gemalto Terminals Ltd
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Filing: 1970-10-16
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Granted: 1971-11-16
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Expires: 1990-10-16
Abstract
Abstract The invention relates to a dual-function switching apparatus intended particularly for controlling the two time bases of a dual time base oscilloscope. This switching apparatus comprises two switch contact assemblies of the wafer type driven in rotation by two coaxial shafts respectively. Each shaft is independently rotated by its own knob, these two knobs also being mounted coaxially one in front of the other. The rear knob has a datum index by which its position can be read on scale markings on the oscilloscope front panel. The front knob also has a datum index used for determining the position of this front knob. But to avoid parallax errors in reading the position of this front datum index on the scale markings, the rear knob is provided with auxiliary indexes which extend from the datum index on the front knob to the scale markings on the panel. When the datum index on the front knob is aligned with any particular auxiliary index on the rear knob, the position of the front knob is read by sighting along that auxiliary index from the front datum index to the scale markings.
Inventors
- 👤 Nicholas Darryl Swinstead
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:20
CPC Classifications
H; H01; H01H; H01H19/00; H01H19/64; H01H19/02; H01H19/10; H01H19/14; H01H2019/143
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
354 words
Electrical switching apparatus intended to be mounted on a panel bearing suitable scale markings on its front for the switching apparatus, the switching apparatus comprising: an independently rotatable rear knob connected to rotate a tubular shaft which drives a switch contact assembly, this rear knob, when the switching apparatus is mounted on the panel, being located with its rear near to the marked front of the panel and having a length in the direction of its axis of rotation sufficient to enable it to be conveniently grasped and rotated by hand, this rear knob further having a datum index located near its rear so that this datum index will lie near the marked panel and can be brought into register with any particular scale marking, by manually rotating the knob, in order to select that scale marking, which then indicates the position of the rear knob and hence of its associated switch contact assembly; and an independently rotatable front knob connected to rotate another shaft which is located inside the tubular shaft and which drives another switch contact assembly, the front knob being located in front of the rear knob and having a length in the direction of its axis of rotation sufficient to enable it to be conveniently grasped and rotated by hand, this front knob further having a datum index located near the rear of the front knob hence near the front of the rear knob; the rear knob further comprising auxiliary indexes extending substantially from the front of the rear knob to substantially the rear of this rear knob, these auxiliary indexes extending sufficiently close to the front knob so that any particular auxiliary index can easily be selected by the datum index of the front knob, by rotating the front knob until its datum index comes into register with that auxiliary index, whereby, when the switching apparatus is mounted on the panel, the position of the front knob and hence of its associated switch contact assembly can be read by following the selected auxiliary index from the datum index on the front knob to the scale markings on the panel.
Claim 2
Dependent Claim
354 words
Electrical switching apparatus intended to be mounted on a panel bearing suitable scale markings on its front for the switching apparatus, the switching apparatus comprising: an independently rotatable rear knob connected to rotate a tubular shaft which drives a switch contact assembly, this rear knob, when the switching apparatus is mounted on the panel, being located with its rear near to the marked front of the panel and having a length in the direction of its axis of rotation sufficient to enable it to be conveniently grasped and rotated by hand, this rear knob further having a datum index located near its rear so that this datum index will lie near the marked panel and can be brought into register with any particular scale marking, by manually rotating the knob, in order to select that scale marking, which then indicates the position of the rear knob and hence of its associated switch contact assembly; and an independently rotatable front knob connected to rotate another shaft which is located inside the tubular shaft and which drives another switch contact assembly, the front knob being located in front of the rear knob and having a length in the direction of its axis of rotation sufficient to enable it to be conveniently grasped and rotated by hand, this front knob further having a datum index located near the rear of the front knob hence near the front of the rear knob; the rear knob further comprising auxiliary indexes extending substantially from the front of the rear knob to substantially the rear of this rear knob, these auxiliary indexes extending sufficiently close to the front knob so that any particular auxiliary index can easily be selected by the datum index of the front knob, by rotating the front knob until its datum index comes into register with that auxiliary index, whereby, when the switching apparatus is mounted on the panel, the position of the front knob and hence of its associated switch contact assembly can be read by following the selected auxiliary index from the datum index on the front knob to the scale markings on the panel.
Claim 3
Dependent Claim
47 words
Switching apparatus according to claim 1, wherein the rear knob together with its associated switch contact assembly rotates in regular stepwise fashion and the indexes of the rear knob are regularly spaced apart by one step or by a multiple or possibly a submultiple of a step.
Claim 4
Dependent Claim
55 words
Switching apparatus accordance to claim 2, wherein the front knob together with its associated switch contact assembly rotates in regular stepwise fashion and the indexes on the rear knob are regularly spaced apart by one step of the front knob or by a multiple or possibly a submultiple of a step of the front knob.
Claim 5
Dependent Claim
74 words
Switching apparatus according to claim 1, wherein the auxiliary indexes on the rear knob are in the form of radially upstanding lugs and the datum index on the front knob is also in the form of a radially upstanding lug, these lugs being positioned and dimensioned so that when the front datum lug is in register with a selected rear auxiliary lug, that auxiliary lug forms a smooth extension of the front datum lug.
Claim 6
Dependent Claim
79 words
Switching apparatus according to claim 1, wHerein the auxiliary indexes on the rear knob are in the form of radial grooves and the datum index on the front knob is in the form of a radially upstanding lug, this lug and the grooves being positioned and dimensioned so that when the front datum lug is in register with a selected groove, the bottom of the selected groove forms a smooth extension of the top of the front datum lug.
Claim 7
Dependent Claim
46 words
Switching apparatus according to claim 2 including the scale-marked panel on which it is mounted, wherein the scale markings are spaced apart by angular distances which are equal to or multiples of or possibly submultiples of the angular spacings of the indexes on the rear knob.
Claim 8
Dependent Claim
38 words
Switching apparatus according to claim 6, wherein when the rear knob is in any of its stepped positions, at least some of the indexes of this rear knob are aligned in register with scale markings on the panel.
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) | 1974-11-15 | 1975-05-17 | 1975-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-15 | 1979-05-17 | 1979-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-15 | 1983-05-17 | 1983-11-16 | $7700.00 | Window Closed / Lapsed |