US3728676A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reverse motion detector
Assignee: ELECTRO DEV CORP
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Filing: 1970-12-02
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Granted: 1973-04-17
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Expires: 1990-12-02
Abstract
Abstract To detect when an object begins to move in a direction opposite or reverse to its normal direction of movement, a magnetic actuator is disposed on the object and a sensor including first and second reed switches is disclosed adjacent to the object. The reed switches are co-planar in the sensor and disposed such that the first reed switch closes before the second reed switch upon relative movement of the object therepast in its reverse direction. In one embodiment, a logic circuit provides an output signal if, and only if, the second reed switch closes in response to this actuator movement after the first reed switch closes and while the first reed switch remains closed. The output signal initiates operation of a timing circuit which provides a timing signal that inhibits further operation of the logic circuit and is applied through an audio oscillator to drive an amplifier and a loud speaker for a short time period. When the timing signal ceases, the logic circuit is automatically reset to detect subsequent reverse object movements. In a preferred embodiment, the apparatus is used as a vehicle back-up alarm in which the magnetic actuator is attached to the vehicle''s drive shaft and the sensor is disposed in proximity thereto.
Inventors
- 👤 R Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 08:20
CPC Classifications
B; B60; B60Q; B60Q5/00; B60Q1/00; B60Q1/02; B60Q1/22; G; G01; G01P; G01P13/00; G01P13/02; G01P13/04
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
203 words
A detector for providing an indication when a vehicle is proceeding in a reverse direction, comprising: a sensor, including first and second spaced switches; a rotational mechanism, the direction of rotation of said mechanism corresponding to the direction of movement of the vehicle, said sensor being stably positioned at a predetermined location relative to said rotational mechanism; means fixedly attached to said rotational mechanism for actuating said first and second switches in a predetermined sequence; logic means responsive to said first and second switches for providing an output signal if, and only if, said first and second switches are actuated in a predetermined sequence, said logic means comprising a first gate providing a signal whenever said first switch is actuated, a second gate providing a signal for a short period of time after the actuation of said second switch, and a third gate providing said output signal only upon coincidence of said signals from said first and said second gates; timing means responsive to said logic means for producing a timing signal for a predetermined period of time after the production of said output signal; and means actuated by said timing means for providing a warning for the duration of said timing signal.
Claim 2
Dependent Claim
203 words
A detector for providing an indication when a vehicle is proceeding in a reverse direction, comprising: a sensor, including first and second spaced switches; a rotational mechanism, the direction of rotation of said mechanism corresponding to the direction of movement of the vehicle, said sensor being stably positioned at a predetermined location relative to said rotational mechanism; means fixedly attached to said rotational mechanism for actuating said first and second switches in a predetermined sequence; logic means responsive to said first and second switches for providing an output signal if, and only if, said first and second switches are actuated in a predetermined sequence, said logic means comprising a first gate providing a signal whenever said first switch is actuated, a second gate providing a signal for a short period of time after the actuation of said second switch, and a third gate providing said output signal only upon coincidence of said signals from said first and said second gates; timing means responsive to said logic means for producing a timing signal for a predetermined period of time after the production of said output signal; and means actuated by said timing means for providing a warning for the duration of said timing signal.
Claim 3
Dependent Claim
25 words
A detector as recited in claim 1 further comprising means for inhibiting the operation of said logic means for the duration of said timing signal.
Claim 4
Dependent Claim
46 words
A detector as recited in claim 1 wherein said means for providing a warning comprises an oscillator providing an audible square wave signal in response to said timing signal, a loudspeaker, and an amplifier means driving said loudspeaker in response to said audible, square wave signal.
Claim 5
Dependent Claim
29 words
A detector as recited in claim 1, wherein said first and second switches both comprise reed switches of a magnetically actuable type, and said actuator includes a permanent magnet.
Claim 6
Independent Claim
179 words
An apparatus for detecting motion of an object in a direction opposite or reverse to that normally encountered comprising: a sensor including first and second switches spaced apart in a predetermined fashion, said first and second switches being actuated in a predetermined sequence in response to the reverse movement of the object; logic means responsive to said first and second switches for providing an output signal if, and only if, said first and second switches are actuated in the predetermined sequence, said logic means comprising a first gate providing a signal whenever said first switch is actuated, a second gate providing a signal for a short period of time after the actuation of said second switch, and a third gate providing said output signal only upon coincidence of said signals from said first and second gates; timing means responsive to said logic means for producing a timing signal for a predetermined period of time after the production of said output signal; and means connected to said timing means for providing a warning for the duration of said timing signal.
Claim 7
Independent Claim
179 words
An apparatus for detecting motion of an object in a direction opposite or reverse to that normally encountered comprising: a sensor including first and second switches spaced apart in a predetermined fashion, said first and second switches being actuated in a predetermined sequence in response to the reverse movement of the object; logic means responsive to said first and second switches for providing an output signal if, and only if, said first and second switches are actuated in the predetermined sequence, said logic means comprising a first gate providing a signal whenever said first switch is actuated, a second gate providing a signal for a short period of time after the actuation of said second switch, and a third gate providing said output signal only upon coincidence of said signals from said first and second gates; timing means responsive to said logic means for producing a timing signal for a predetermined period of time after the production of said output signal; and means connected to said timing means for providing a warning for the duration of said timing signal.
Claim 8
Dependent Claim
25 words
A detector as recited in claim 5 further comprising means for inhibiting the operation of said logic means for the duration of said timing signal.
Claim 9
Dependent Claim
46 words
A detector as recited in claim 5 wherein said means for providing a warning comprises an oscillator providing an audible square wave signal in response to said timing signal, a loudspeaker, and an amplifier means driving said loudspeaker in response to said audible, square wave signal.
Claim 10
Dependent Claim
22 words
A detector as recited in claim 5 wherein said first and second switches both comprise reed switches of a magnetically actuable type.
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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) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |