Patent EP0133748A1 successfully refreshed from Google Patents.
EP0133748A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method for detecting and obtaining information about changes in variables
Assignee: Raychem Corp
•
Filing: 1984-06-29
•
Granted: —
•
Expires: 2004-06-29
Abstract
Abstract Method and apparatus for detecting and obtaining information about (particularly locating) an event (E), i.e. a change in a variable, for example a liquid leak. In a preferred embodiment, two conductors (11,12) follow an elongate path and are connected to each other through a power source, preferably a constant current source (15). In the absence of an event, the two conductors (11, 12) are electrically insulated from each other at all points along the path. When an event (E) occurs, the two conductors (11, 12) become electrically connected at a connection point at which the event occurs, thus completing a test circuit in which a current of known size then flows. When using a constant current source (15), the size of the current does not depend on the resistance of the connection. One of the conductors is a locating member having known impedance characteristics along its length, and by measuring the voltage drop between the connection point and one end of the locating member, the location of the event can be calculated. The voltage drop can conveniently be measured by means of a third conductor which connects, via a high impedance a voltmeter (14), the ends of the locating member.
Inventors
- 👤 Michael Masia
- 👤 James Patrick Reed
- 👤 Peter Leonard Brooks
- 👤 Thomas Winton Tolles
- 👤 Larry Russell Reeder
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 18:11
CPC Classifications
G; G01; G01M; G01M3/00; G01M3/02; G01M3/04; G01M3/042; G01M3/045; G01M3/16; G01M3/165; G01M3/18; G01R; G01R31/00; G01R31/08; G01R31/081; G01R31/083; G08; G08B; G08B23/00; G08B25/00; G08B25/01; G08B25/018
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
204 words
A method for monitoring for the occurrence of an event, and for detecting and obtaining information about the event upon its occurrence, which method comprises providing a system in which, upon occurrence of the event, (1) electrical connection is made between an electrically conductive locating member and an electrically conductive source member; the connection to the locating member being effective at a first point whose location is defined by at least one characteristic of the event; the making of the connection enabling the formation of a test circuit which comprises (a) the connection, (b) that part of the locating member which lies between the first point and a second point having a known location on the locating member, and (c) a power source which causes an electrical current of known size to be transmitted between the first and second points on the locating member; and the current and the locating member being such that, by measuring the voltage drop between the first and second points, the spatial relationship between the first and second points can be determined; (2) the voltage drop between the first and second points is measured; and (3) information concerning the event is obtained from the measurement made in step (2).
Claim 2
Independent Claim
204 words
A method for monitoring for the occurrence of an event, and for detecting and obtaining information about the event upon its occurrence, which method comprises providing a system in which, upon occurrence of the event, (1) electrical connection is made between an electrically conductive locating member and an electrically conductive source member; the connection to the locating member being effective at a first point whose location is defined by at least one characteristic of the event; the making of the connection enabling the formation of a test circuit which comprises (a) the connection, (b) that part of the locating member which lies between the first point and a second point having a known location on the locating member, and (c) a power source which causes an electrical current of known size to be transmitted between the first and second points on the locating member; and the current and the locating member being such that, by measuring the voltage drop between the first and second points, the spatial relationship between the first and second points can be determined; (2) the voltage drop between the first and second points is measured; and (3) information concerning the event is obtained from the measurement made in step (2).
Claim 3
Dependent Claim
33 words
A method according to claim 1 wherein (a) the locating member and the source member are elongate; and (b) the second point is a fixed point at one end of the locating member.
Claim 4
Dependent Claim
23 words
A method according to claim 1 or 2 wherein the power source is a controlled current source which delivers a known fixed current.
Claim 5
Dependent Claim
21 words
A method according to claim 3 wherein the controlled current source supplies a known current which is less than 10 milliamps.
Claim 6
Independent Claim
111 words
A method according to any one of the preceding claims wherein the voltage drop between the first and second points is determined by means of a voltage-measuring device which forms part of a reference circuit, the reference circuit comprising (a) the voltage-measuring device, (b) that part of the locating member which lies between the first and second points, and (c) an electrically conductive return member which (i) is electrically connected to the locating member at the ends thereof, and (ii) is otherwise insulated from the locating member, the voltage-measuring device having an impedance which ' is very high by comparison with the impedance of the other components of the reference circuit.
Claim 7
Independent Claim
54 words
A method according to any one of the preceding claims which also comprises switching the components of the system from a first arrangement in which the second point is at one end of the locating member to a second arrangement in which the second point is at the opposite end of the locating member.
Claim 8
Independent Claim
27 words
A method according to any one of the preceding claims wherein the connection between the locating member and the source member has a substantial and unknown impedance.
Claim 9
Independent Claim
49 words
A method according to any one of the preceding claims wherein information concerning the event is obtained in step (3) only when the ratio V/I is within a predetermined range, wherein V is the output voltage of the power source and I is the current in the test circuit.
Claim 10
Dependent Claim
45 words
A method according to claim 8 wherein the power source is a controlled current source which delivers current at a fixed value, and information is obtained in step (3) only when the current between the first and second points is substantially at said fixed value.
Claim 11
Independent Claim
108 words
A method according to any one of the preceding claims wherein (a) the locating member has a total impedance z t o t al ; and the connection to the locating member being effective at a first point whose location is defined by at least one characteristic of the event; (b) the test circuit also includes a component which (i) is connected in series with that part of the locating member between the first point and a second point, and (ii) has an impedance substantially equal to the difference between Z total impedance of that part of the locating member between the first point and the second point.
Claim 12
Dependent Claim
30 words
A method according to claim 10 wherein the source member has substantially the same impedance characteristics as the locating member, and said component is a part of the source member.
Claim 13
Dependent Claim
23 words
A method according to claim 10 or 11 which also comprises measuring the impedance of the connection between the locating and source members.
Claim 14
Independent Claim
64 words
A method according to any one of the preceding claims wherein the locating member comprises (1) a plurality of spaced-apart locating zones, each of said zones providing a series of points to which the connection can be made, and (2) a plurality of spaced-apart connection zones which physically separate and electrically connect the locating zones and which cannot become connected to the source member.
Claim 15
Independent Claim
35 words
A method according to any one of the preceding claims wherein the locating member has a temperature coefficient of impedance which averages less than 0.003 per degree C over the temperature range 0 to 100°C.
Claim 16
Independent Claim
108 words
A method according to any one of the preceding claims wherein the locating member comprises (A) an elongate core which is composed of a metal whose temperature coefficient of resistivity averages less than 0.003 per degree C over the temperature range 0° to 100°C and in which each longitudinal section has a resistance from 10 -4 to 10 4 ohms/foot; and (B) an elongate jacket which is composed of a conductive polymer, which electrically surrounds the core and in which each longitudinal section has a resistance which is at least 100 times the resistance of the core of that longitudinal section at all temperatures from 0° to 100°C.
Claim 17
Independent Claim
61 words
A method according to any one of the preceding claims wherein (1) at least a part of at least one of the locating and source members comprises an elongate metal core which is electrically surrounded by an elongate jacket composed of a conductive polymer, and (2) the event is the presence of sufficient electrolyte to connect the locating and source members.
Claim 18
Dependent Claim
63 words
A method according to claim 1 wherein the event is a change in the concentration of a particular substance, and the locating and source members are physically contacted by a connecting member which insulates them from each other prior to said change and which effects or permits electrical connection between the locating member and the source member as a result of said change.
Claim 19
Dependent Claim
70 words
A method according to claim 1 wherein event- monitoring is required only in spaced-apart zones, and the locating member comprises (a) a plurality of spaced-apart locating components which are in said zones and to which connection is made upon occurrence of an event, and (b) a plurality of spaced-apart intermediate components which physically separate and electrically connect the locating components and which cannot become directly connected to the source member.
Claim 20
Dependent Claim
265 words
Apparatus suitable for use in the method claimed in any one of claims 1 to 18, which apparatus comprises (1) an elongate locating member whose impedance from one end to any point thereon defines the spatial relation ship between that end and that point; (2) an elongate source member; (3) an event-sensitive connection means which, upon occurrence of an event, effects electrical connection between the locating member and the source member, the connection being effective at a first point on the locating member which is defined by at least one characteristic of the event; (4) a voltage-measuring device for determining the voltage drop between the first point and a second point which is at one end of the locating member; (5) a power source which is electrically connected to the second point on the locating member and, in the absence of an event, is not otherwise connected to the locating member; and (6) a return member having a first end which is electrically connected to one end of the locating member via the voltage-measuring device and a second end which is electrically connected to the other end of the locating member, the return member being otherwise insulated from the locating member; whereby upon occurrence of an event which causes an electrical connection between the locating and source members, this enables the formation of the test circuit and a reference circuit which comprises the voltage-measuring device, the locating member, and the return member, the voltage-measuring device having an impedance which is very high by comparison with the impedance of the other components of the reference circuit.
Claim 21
Dependent Claim
24 words
Apparatus according to claim 19 wherein the power source is a controlled current source which, when an event occurs, supplies a known fixed current.
Claim 22
Dependent Claim
54 words
Apparatus according to claim 19 or 20 which includes means for preventing the display of information about the event if the value of the ratio V/I is outside a predetermined range, wherein I is the output voltage of the power source in volts and I is the current in the test circuit in amps.
Claim 23
Dependent Claim
22 words
Apparatus according to any of claims 19 to 21 wherein the source member has the same impedance characteristics as the locating member.
Claim 24
Dependent Claim
122 words
An elongate article which is suitable for use as the locating member in a method as claimed in any of claims 1 to 18, said article comprising (A) an elongate core which is composed of a metal whose temperature coefficient of resistivity averages less than 0.003 per degree Centigrade over the temperature range 0° to 100°C and in which each longitudinal section has a resistance which is from 10 -4 to 10 4 ohms/foot, and (B) an elongate jacket which is composed of a conductive polymer, which electrically surrounds the core, and in which each longitudinal section has a resistance which is at least 100 times the resistance of the core of that longitudinal section at all temperatures from 0° to 100°C.
Claim 25
Dependent Claim
40 words
An article according to claim 23 which has a resistance of 1 to 20 ohm/foot (3.3 to 65 ohm/meter) and a temperature coefficient of resistance which averages less than 0.0003 per degree Centigrade in the temperature range 0° to 100°C.
Claim 26
Dependent Claim
192 words
An event-sensitive module which is suitable for use as a component in a method as claimed in claim 10, 11 or 12, the module comprising (1) a first impedant component having substantial impedance; (2) a first conductor which has a relatively very small impedance and one end of which is connected to the first impedant component; (3) a second impedant component having the same impedance as the first impedant component; (4) a second conductor which has a relatively very small impedance and one end of which is connected to the second impedant component; the first impedant component and the first conductor, in the absence of an event, being electrically insulated from the second conductor and the second impedant component; and (5) an event-sensitive connection means which, upon occurrence of an event, can effect electrical connection between the first and second conductors; the first impedant component and the first conductor being connectable in series with incoming and outgoing portions of intermediate components of an elongate locating member, and the second impedant component and the second conductor being connectable in series with incoming and outgoing portions of intermediate components of an elongate source member.
Claim 27
Dependent Claim
51 words
A module according to claim 25 which also comprises a third impedant component connected to the other end of the first conductor, and a fourth impedant component connected to the other end of the second conductor, the third and fourth components having the same impedance as the first and second components.
Claim 28
Dependent Claim
154 words
Apparatus which is suitable for use in a method as defined in claim 8 or 9 and which comprises (1) a first terminal; (2) a second terminal; (3) a third terminal; (4) means for connecting the first and second terminals to a power source; (5) a voltage-measuring device for measuring the voltage drop between the second and third terminals; (6) a display unit for displaying information derived from a voltage drop measured by the voltage-measuring device; and (7) a device which, when the first and second terminals are connected to a power source and are connected to each other through a locating member and a source member, thus forming a test circuit, prevents the display unit from displaying information if the value of the ratio V/I is outside a predetermined range, where I is the current in the test circuit in amps and V is the output voltage of the power source in volts.
Claim 29
Dependent Claim
63 words
Apparatus according to claim 26 which is adapted to be connected to a fixed voltage AC power source and which comprises a constant current source which converts the AC input into a DC current of controlled size, and the device (7) is a current-sensitive device which prevents the display of information if the current in the test circuit falls below the controlled size.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.