EP0003412A2
Expired / Lapsed
EP
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Electric delay device
Assignee: Imperial Chemical Industries Ltd
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Filing: 1979-01-18
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Granted: —
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Expires: 1999-01-18
Abstract
Abstract Separate electrical timing and load activation devices are provided for each of plural electrical loads and each device is in use connected to receive reference timing signals from a remote central unit. Each of the separate timing and toad activation devices measures a reference time interval accurately defined by the reference timing signals and subsequently activates its associated electrical load after a respectively corresponding predetermined time delay which is determined as a function of the locally measured reference time interval. The time interval may advantageously be measured by counting locally generated clock pulses, for example, in an up-down counter which after counting the pulses between two reference timing signals reverses direction and activates the load when the count reaches the initial value. The devices are especially useful for firing electric fuseheads for blasting detonators in a predetermined delay sequence.
Inventors
- 👤 Ian John Kirby
- 👤 Michael Ian Mitchell
- 👤 Andrew Stratton
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 19:35
CPC Classifications
H; H03; H03K; H03K5/00; H03K5/13; H03K5/131; F; F42; F42B; F42B3/00; F42B3/10; F42B3/12; F42B3/121; F42B3/122; F42D; F42D1/00; F42D1/04; F42D1/045; F42D1/05; F42D1/055; G; G01; G01V; G01V1/00; G01V1/02; G01V1/04; G01V1/06; G01V1/08; G04; G04F; G04F1/00; G04F1/005
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
76 words
An electrical timing device for activating an electrical load after a predetermined time delay operable in.conjunction with a remote unit which provides accurately timed reference signals, said device comprising: time interval measuring means adapted to receive said accurately timed reference signals and to measure a first time interval associated therewith, and output means for thereafter activating said electrical load after said predetermined time delay which is determined as a function of said measured first time interval.
Claim 2
Dependent Claim
76 words
An electrical timing device for activating an electrical load after a predetermined time delay operable in.conjunction with a remote unit which provides accurately timed reference signals, said device comprising: time interval measuring means adapted to receive said accurately timed reference signals and to measure a first time interval associated therewith, and output means for thereafter activating said electrical load after said predetermined time delay which is determined as a function of said measured first time interval.
Claim 3
Dependent Claim
46 words
An electrical timing device as claimed in Claim 1 further comprising: energy storage means connected to receive and store electrical energy from said remote unit and to supply at least a portion of such stored energy to its associated electrical load after said predetermined time delay.
Claim 4
Dependent Claim
56 words
An electrical timing device as claimed in Claim 2 further comprising: an energy dissipation means connected to substantially deplete said energy storage means of its stored energy within a predetermined time after its last receipt of energy from said central unit thereby disabling the device if its electrical load is not activated within such predetermined time.
Claim 5
Dependent Claim
123 words
An electrical timing device as claimed in any one of Claims 1 to 3 inclusive wherein said accurately timed reference signals comprise a sequence of accurately timed events and wherein: said time interval measuring means comprises a source of locally generated clock pulses, preset counter means for counting said timed events and for providing first and second signals respectively corresponding to first and second predetermined counter contents, and a timing counter means for counting the number of clock pulses occurring between said first and second signals; and said output means comprises means for activating the electrical load after a subsequent time delay measured by again counting said clock pulses as a function of the number earlier counted between said first and second signals.
Claim 6
Dependent Claim
78 words
An electrical timing device as claimed in Claim 4 wherein: said timing counter means comprises an up-down counter connected to count in one direction from an initial predetermined content between the occurrence of said first and second signals and to subsequently count in the opposite direction; and said output means is connected to said.up-down counter to detect the time when its contents again equals said initial predetermined content and to activate the connected electrical load in response therero.
Claim 7
Dependent Claim
56 words
An electrical timing device as claimed in Claim 4 or Claim 5 wherein said preset counter means includes: a digital counter, logic means connected to provide said first signal when a preset content of the digital counter is established, and means to provide said second signal when the maximum content of the digital counter is established.
Claim 8
Dependent Claim
45 words
An electrical timing device as claimed in any one of Claims 4 to 6 inclusive wherein said output means include logic means which permits activation of the electrical load only if the digital counter of the preset counter means had previously reached a predetermined content.
Claim 9
Dependent Claim
36 words
An electrical timing device as claimed in any one of Claims 1 to 7 inclusive comprising: discrimination means for minimizing the possibility that spurious electrical inputs thereto would result in activation of the connected electrical load.
Claim 10
Dependent Claim
118 words
An electrical timing device as claimed in any one of Claims 1 to 8 inclusive comprising: means to receive a train of reference signals, a preset signal selecting system having means to select a first and a second of said reference signals as control signals and to generate first and second timing signals in response to said first and second control signals respectively, means to generate a starting signal, and timing means to measure the interval between said first and second timing signals and to generate an output signal whereby the corresponding load is connected to an energy supply at a time interval after the starting signal determined by the interval between the first and second timing signals.
Claim 11
Dependent Claim
47 words
An electrical timing device as claimed in any one of Claims 1 to 9 inclusive including signal discriminator means to identify duration of frequency characteristics of the reference signals whereby only signals having selected duration or frequency characteristics will be passed for use by the timing means.
Claim 12
Dependent Claim
51 words
An electrical timing device as claimed in any one of Claims 1 to 10 inclusive including means to separate or derive control signals from a remote energy supply, means to preset the correct starting conditions for the timing means, and means to protect the timing device from damage by excess voltage.
Claim 13
Dependent Claim
52 words
An electrical timing device as claimed in Claim 10 wherein said preset signal selecting system comprises: an electronic digital counter having logic elements whereby the state of the logic elements represents the count of control signals and the first and second timing signals are generated by the attainment of predetermined logic states.
Claim 14
Dependent Claim
97 words
An electrical timing device as claimed in Claim 12 wherein said logic elements comprise: a first logic register having said first predetermined number permanently set thereinto, and a first logic comparator for comparing the contents of the counter compared with the state of the first logic register thereby generating a first timing signal when the counter contents and the state of the first logic register are identical, a second register having said second predetermined number permanently set thereinto, and a second logic comparator which generates the second timing signal at the count of the second predetermined number.
Claim 15
Dependent Claim
45 words
An electrical timing device as claimed in any one of Claims 1 to 13 inclusive wherein the time interval measuring means comprises: a clock pulse generator containing an oscillator, and a reversible electronic digital counter connected to receive clock pulses from said clock pulse generator.
Claim 16
Dependent Claim
51 words
A time delay electric fusehead assembly for use in conjunction with a remote fire control unit providing accurately timed reference signals, said fusehead assembly comprising: in combination an electrical timing device as claimed in any one of Claims 1 to 14 inclusive and an electric fusehead connected as said electrical load.
Claim 17
Dependent Claim
18 words
The combination of a time delay electric fusehead assembly as claimed in Claim IE and a blasting detonator.
Claim 18
Dependent Claim
56 words
An explosives firing control system for selectively energizing a plurality of electric fuseheads after respectively corresponding predetermined time delays, said system comprising: a fire control unit located at a remote site for providing reference timing signals and electrical energy for use in energizing said fuseheads and plural delay electric fusehead assemblies as claimed in Claim 15.
Claim 19
Independent Claim
100 words
A method for selectively activating a plurality of electrical loads at respectively corresponding predetermined relative times, said method comprising the steps of: generating reference timing signals at a central location; separately receiving and processing said reference timing signals at the site of each electrical load; said processing step at each site including the measurement of a respectively corresponding reference time interval defined by said reference timing signals and subsequently measuring a respectively corresponding predetermined time delay as a function of the earlier measured reference time interval; and activating each electrical load after its respectively corresponding predetermined time delay has elapsed.
Claim 20
Independent Claim
100 words
A method for selectively activating a plurality of electrical loads at respectively corresponding predetermined relative times, said method comprising the steps of: generating reference timing signals at a central location; separately receiving and processing said reference timing signals at the site of each electrical load; said processing step at each site including the measurement of a respectively corresponding reference time interval defined by said reference timing signals and subsequently measuring a respectively corresponding predetermined time delay as a function of the earlier measured reference time interval; and activating each electrical load after its respectively corresponding predetermined time delay has elapsed.
Claim 21
Dependent Claim
66 words
A method as claimed in Claim 18 further comprising the steps of: transmitting electrical energy from said central location to each of said sites in conjunction with the transmission of said reference timing signals, and receiving and storing said electrical energy at each of said sites, and using at least a portion of said stored energy at each site to activate the respectively associated electrical load.
Claim 22
Dependent Claim
80 words
A method as in Claim 18 or Claim 19 wherein said reference timing signals comprise a sequence of accurately timed events and wherein said measurement step at each load site comprises: locally generating a source of clock pulses, counting clock pulses occurring between said first and second signals, and subsequently measuring said predetermined time delay by counting a number of clock pulses bearing a predetermined relationship to the number of clock pulses earlier counted between said first and second signals.
Claim 23
Independent Claim
120 words
A method of energizing an electrical load at a predetermined delay after a starting signal, said method comprising: feeding control signals at accurately timed intervals to a preset signal selecting system wherein two control signals characteristic of the desired delay are selected, generating first and second timing signals in response to each of said two selected control signals, feeding said first and second timing signals to timing means wherein the time interval between the said first and second timing signals is measured, generating a starting signal and, after a delay period from said starting signal that is determined by the time interval between said first and second timing signals as measured by the timing means, feeding energy to the load..
Claim 24
Independent Claim
120 words
A method of energizing an electrical load at a predetermined delay after a starting signal, said method comprising: feeding control signals at accurately timed intervals to a preset signal selecting system wherein two control signals characteristic of the desired delay are selected, generating first and second timing signals in response to each of said two selected control signals, feeding said first and second timing signals to timing means wherein the time interval between the said first and second timing signals is measured, generating a starting signal and, after a delay period from said starting signal that is determined by the time interval between said first and second timing signals as measured by the timing means, feeding energy to the load..
Claim 25
Dependent Claim
29 words
A method as claimed in Claim 21 wherein said control signals comprise accurately timed signals fed from a remote position to an expendable timing means adjacent to the load.
Claim 26
Dependent Claim
93 words
A method as claimed in Claim 21 or Claim 22 wherein a series of electric fuseheads are energized in timed sequence by feeding said control signals simultaneously to a series of said signal selecting systems, each signal selecting system being associated with an individual electrical load of the series and preset individually to select two respectively corresponding control signals for each load in accordance with the desired energizing sequence whereby energy is fed successively to each load at a time determined by the interval between the particular control signals selected for the load.
Claim 27
Independent Claim
78 words
A method as claimed in any one of Claims 21 to 23 inclusive wherein said two characteristic control signals are selected by: counting the occurrences of control signals, determining when the count of control signals equals a first predetermined number thereby identifying the first characteristic control signal and generating the first timing signal, determining when the count of control signals equals a second predetermined number, said.equality identifying the second characteristic control signal and generating the second timing signal.
Claim 28
Dependent Claim
33 words
A method as claimed in Claim 24 wherein the counting of the control signals is performed by an electronic counter including preset means for. determining when the count attains the said predetermined numbers.
Claim 29
Dependent Claim
135 words
A method as-claimed in Claim 24 or Claim 25 wherein the timing means comprises a clock pulse generator and a reversible counter adapted to count said clock pulses and the delay period between the starting signal and the energizing of the load is determined by: counting said clock pulses in one direction in response to the first timing signal, stopping said count in response to the second timing signal, generating the starting signal for the energizing sequence at a predetermined time after the second timing signal, starting a reverse count of clock pulses in response to said starting signal whereby the number of clock pulses is substracted from the aforesaid number held in the counter, and feeding energy to the load when the count has returned to the count initially contained in the reversible counter.
Claim 30
Independent Claim
64 words
A method as claimed in any one of Claims 21 to 26 inclusive wherein the energy for energizing the electrical load together with any additional energy required for the signal selecting system and timing means is supplied from a remote source of alternating or direct electrical current, the said control signals comprising interruptions of or modifications to said alternating or direct electrical current supply.
Claim 31
Independent Claim
80 words
A method as claimed in any one of Claims 18 to 27 inclusive wherein the load or loads comprise electrical fusehead and an energy store comprising a capacitor is charged from said source of alternating or direct current and is disposed adjacent to each fusehead, from which store the required energy is supplied even if the wires connecting the energy source to the fusehead assembly are broken after the generation of the starting signal but before the fusehead is fired.
References Cited (Backward Citations)
No citation records indexed.
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