Patent US3629678A successfully refreshed from Google Patents.
US3629678A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Proximity switch
Assignee: Robertshaw Controls Co
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Filing: 1969-12-15
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Granted: 1971-12-21
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Expires: 1989-12-15
Abstract
Abstract A proximity switch operable in response to the position of a movable object and including a pulse-forming circuit for generating a series of pulses in a first coil, and a detecting network including a second coil for energizing a load whenever a pulse from the first coil is induced in the second coil. The first and second coils are positioned such that the degree of coupling therebetween is responsive to the proximity of the object for controlling the energization of the load.
Inventors
- 👤 Hugh J Tyler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:15
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/94; H03K17/945; H03K17/95; H03K17/952; H03K17/9525; H03K17/51; H03K17/56; H03K17/72; H03K17/722; H03K17/723
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
128 words
A proximity switch operable in response to the position of a movable object comprising input means adapted to be connected with a source of power, pulse generator means connected with said input means for generating a series of pulses, load means connected with said input means, detecting means connected to said load means and said input means and responsive to pulses from said pulse generator means to energize said load means, and coupling means connected to said pulse generator means and said detecting means and positioned adjacent the movable object for selectively enabling electromagnetic coupling of said pulses from said pulse generator means to said detecting means in response to the position of the movable object whereby energization of said load means is controlled by the movable object.
Claim 2
Dependent Claim
128 words
A proximity switch operable in response to the position of a movable object comprising input means adapted to be connected with a source of power, pulse generator means connected with said input means for generating a series of pulses, load means connected with said input means, detecting means connected to said load means and said input means and responsive to pulses from said pulse generator means to energize said load means, and coupling means connected to said pulse generator means and said detecting means and positioned adjacent the movable object for selectively enabling electromagnetic coupling of said pulses from said pulse generator means to said detecting means in response to the position of the movable object whereby energization of said load means is controlled by the movable object.
Claim 3
Dependent Claim
32 words
The invention as recited in claim 1 wherein said coupling means includes first and second spaced coils and said movable object is movable in the space between said first and second coils.
Claim 4
Dependent Claim
28 words
The invention as recited in claim 2 wherein said first coil is connected to said pulse generator means and said second coil is connected to said detecting means.
Claim 5
Dependent Claim
25 words
The invention as recited in claim 3 wherein said detecting means includes a first controlled rectifier having a gate electrode connected to said second coil.
Claim 6
Dependent Claim
58 words
The invention as recited in claim 4 wherein said pulse generator means includes a breakdown device conneCted with said first coil to form a series network, a capacitor connected in parallel with said series network, and a resistor connected at one end with said capacitor and said breakdown device and at the other end with said input means.
Claim 7
Dependent Claim
25 words
The invention as recited in claim 5 wherein said breakdown device comprises a unidirectionally conducting diode having a predetermined breakdown voltage in its forward direction.
Claim 8
Dependent Claim
26 words
The invention as recited in claim 6 wherein said input means supplies an AC voltage, and said diode is poled to conduct on positive half-cycles only.
Claim 9
Dependent Claim
27 words
The invention as recited in claim 7 wherein said first controlled rectifier is connected to said input means and is poled to conduct on positive half-cycles only.
Claim 10
Dependent Claim
21 words
The invention as recited in claim 8 wherein said coupling means includes a resistor connected in parallel with said second coil.
Claim 11
Dependent Claim
55 words
The invention as recited in claim 8 wherein said detecting means includes circuit means connected to said first controlled rectifier, said load means, and said input means, for conducting current to said load means on negative half-cycles of said AC voltage in response to the conducting of said first controlled rectifier during preceding positive half-cycles.
Claim 12
Dependent Claim
62 words
The invention as recited in claim 10 wherein said circuit means includes a second controlled rectifier connected in parallel with said first controlled rectifier and poled to conduct on negative half-cycles of said AC voltage only, and capacitive storage means connected to said input means for storing a triggering potential for said second controlled rectifier when said first controlled rectifier is conductive.
Claim 13
Dependent Claim
44 words
The invention as recited in claim 11 wherein said capacitive storage means includes a resistor, a first diode and a capacitor connected in series across said load means, said capacitor and said first diode connected with a gate electrode of said second controlled rectifier.
Claim 14
Dependent Claim
29 words
The invention as recited in claim 12 wherein said capacitor and said first diode are connected with said gate electrode of said second controlled rectifier by a second diode.
Claim 15
Dependent Claim
60 words
The invention as recited in claim 10 wherein said circuit means includes an inductor and a first diode connected in series with said first controlled rectifier, said inductor and said first diode being connected with the gate electrode of a second controlled rectifier connected to said input means and poled to conduct on negative half-cycles of said AC input signal.
Claim 16
Dependent Claim
44 words
The invention as recited in claim 14 wherein said inductor and said first diode are connected with the gate of said second controlled rectifier by a second diode, and a resistor is connected between the gate and cathode electrodes of said second controlled rectifier.
Claim 17
Dependent Claim
15 words
The invention as recited in claim 15 wherein said load means comprises an AC motor.
Claim 18
Dependent Claim
29 words
The invention as recited in claim 1 wherein said pulse generator means and said detecting means are connected to said input means and said load means by rectifier means.
Claim 19
Dependent Claim
39 words
The invention as recited in claim 17 wherein said input means supplies an AC voltage, and said rectifier means comprises a full-wave rectifier poled to produce positive half-wave rectified voltage to said pulse generator means and said detecting means.
Claim 20
Dependent Claim
25 words
The invention as recited in claim 18 wherein said coupling means includes a first and a second coil and said movable object is movable therebetween.
Claim 21
Dependent Claim
63 words
The invention as recited in claim 19 wherein said pulse generator means includes a capacitor connected in parallel with a series network formed by the connection of a breakdown device and said first coil, said breakdown device being poled to conduct a positive half-cycles only whereby a voltage pulse is produced in said first coil during each positive half-cycle of said AC voltage.
Claim 22
Dependent Claim
57 words
The invention as recited in claim 20 wherein said detecting means includes a controlled rectifier poled to conduct on positive half-cycles and having a gate electrode connected to said second coil whereby said controlled rectifier is rendered conductive by said voltage pulse produced in said first coil when said pulse is inductively coupled to said second coil.
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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) | 1974-12-20 | 1975-06-21 | 1975-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-20 | 1979-06-21 | 1979-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-20 | 1983-06-21 | 1983-12-21 | $7700.00 | Window Closed / Lapsed |