Patent EP0113512A2 successfully refreshed from Google Patents.
EP0113512A2
Expired / Lapsed
EP
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Motion detection systems
Assignee: ZF International UK Ltd
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Filing: 1983-11-16
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Granted: —
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Expires: 2003-11-16
Abstract
Abstract A motion detector system includes an ultrasonic transmitter (12), receiver (13,14) and phase detector 915) which produces as output signals of frequency related to the speed of movement of any moving object in a zone being monitored. The output of the phase detector is fed to two separate bandpass filters (16,17) having different pass-bands characteristic ofthe frequencies generated by a human being moving in the zone being monitored. A warning is sounded only when signals have been present in both bands for more than a predetermined period.
Inventors
- 👤 Michael John Walker
- 👤 Jeffry Albert Bagnall
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 19:29
CPC Classifications
G; G01; G01S; G01S15/00; G01S15/02; G01S15/50; G01S15/52; G01S15/523; G08; G08B; G08B13/00; G08B13/16; G08B13/1609; G08B13/1618; G08B13/1627
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
136 words
A motion detector system comprising a transmitter device for transmitting oscillatory signals into a zone to be monitored, a receiver device for receiving signals reflected from objects within the zone to be monitored, a phase comparator device receiving electrical inputs from the transmitter device and the receiver device and providing an oscillatory output the frequency of which is dependent on the speed of any movement of an object in the zone to be monitored, filter means connected to the phase comparator device and having a characteristic matched to a movement profile of a specific type of object to be detected, and means connected to the output of the filter means to provide a warning signal only when the movement profile of an object in the zone to be monitored matches the characteristic of said filter means.
Claim 2
Dependent Claim
136 words
A motion detector system comprising a transmitter device for transmitting oscillatory signals into a zone to be monitored, a receiver device for receiving signals reflected from objects within the zone to be monitored, a phase comparator device receiving electrical inputs from the transmitter device and the receiver device and providing an oscillatory output the frequency of which is dependent on the speed of any movement of an object in the zone to be monitored, filter means connected to the phase comparator device and having a characteristic matched to a movement profile of a specific type of object to be detected, and means connected to the output of the filter means to provide a warning signal only when the movement profile of an object in the zone to be monitored matches the characteristic of said filter means.
Claim 3
Dependent Claim
35 words
A motion detector system as claimed in claim 1 in which said filter means comprises two filter circuits which have different pass-bands and which are each connected to the output of the phase comparator device.
Claim 4
Dependent Claim
23 words
A motion detector system as claimed in claim 2 in which said filter circuits have pass-bands of 28-38 Hz and 120-190 Hz respectively.
Claim 5
Dependent Claim
41 words
A motion detector circuit as claimed in claim 3 in which the outputs of the two filter circuits are combined to produce a warning signal only when the output of the phase comparator device contains components in both pass bands simultaneously.
Claim 6
Dependent Claim
45 words
A motion detector circuit as claimed in claim 4 in which the outputs of the filter circuits are combined by means of a combining circuit which produces an output only if the output of the filter circuits exceed a predetermined threshold for a predetermined time.
Claim 7
Dependent Claim
79 words
A motion detector circuit as claimed in claim 5 in which said combining circuit comprises an amplitude detector circuit for each filter output, a time constant circuit for each amplitude detector circuit, a threshold detector circuit for each time constant circuit, each time constant circuit connecting the output of the associated amplitude detector circuit to the input of the associated threshold detector circuit, and a single gate have inputs connected to the outputs of the respective threshold detector circuit.
Claim 8
Dependent Claim
63 words
A motion detector circuit as claimed in claim 6 in which each amplitude detector circuit comprises a voltage comparator having its input a.c. coupled to the output of the associated filter circuit and biased so that the output of the voltage comparator is continuously of one polarity except during peaks in the output waveform of the filter circuit which exceed a predetermined voltage.
Claim 9
Dependent Claim
14 words
A motion detector circuit substantially as hereinbefore described with reference to the accompanying drawings.
Claim 10
Dependent Claim
14 words
A motion detector circuit substantially as hereinbefore described with reference to the accompanying drawings.
References Cited (Backward Citations)
No citation records indexed.
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