GB2313945A

GB2313945A - Fluid flow control device

Info

Publication number: GB2313945A
Application number: GB9609801A
Authority: GB
Inventors: Peter Harrie
Original assignee: Schlumberger Industries Ltd
Current assignee: Gemalto Terminals Ltd
Priority date: 1996-05-10
Filing date: 1996-05-10
Publication date: 1997-12-10
Anticipated expiration: 2016-05-10
Also published as: GB2313945B; GB9609801D0

Abstract

A fluid flow control device for controlling the flow of fluid to a consumer via a meter, 18, comprises an electrically-operable valve 12 and a microprocessor 16 for controlling the operation of the valve, the microprocessor having a first input 22 for receiving pulses representative of the flow rate of the fluid passing through the meter 18 and a second input 32 for receiving a data signal including data representative either of a prepayment made by the consumer and the fluid supply tariff or of a volume of the fluid equivalent in value to a prepayment made by the consumer, the microprocessor being arranged to close the valve when a volume of the fluid determined by the prepayment has passed through the meter.

Description

FLUID FLOW CONTROL DEVICES This invention relates to fluid flow control devices, and is more particularly but not exdusively concerned with fluid flow control devices for controlling a metered gas supply to a consumer.

Gas is typically supplied to consumers, especially domestic consumers, on either credit terms or prepayment terms, the latter frequently involving the use of a prepayment token in the form of a memory device, eg a smart card or a magnetic card, having credit and other data stored in it.

Currently, this normally requires two entirely different kinds of gas meter1 so that changing a consumer's terms of supply is expensive and inconvenient. It is an object of the present invention to alleviate this problem.

According to a first aspect of the present invention, there is provided a fluid flow control device for controlling the flow of fluid to a consumer via a meter, the device comprising an electrically-operable valve and a microprocessor for controlling the operation of the valve, the microprocessor having a first input for receiving pulses representative of the flow rate of the fluid passing through the meter and a second input for receiving a data signal including data representative either of a prepayment made by the consumer and the fluid supply tariff or of a volume of the fluid equivalent in value to a prepayment made by the consumer, the microprocessor being arranged to close the valve when a volume of the fluid determined by the prepayment has passed through the meter.

The term 4input as used herein is to be understood as embracing not only a single input terminal, but also a plurality of related input terminals.

Advantageously, the microprocessor is arranged to accumulate said pulses to determine the total quantity of the gas which has passed through the meter, and the device further includes a non-volatile memory for storing a signal representative of said total quantity.

In a preferred embodiment of the invention, the microprocessor has a third input for receiving control signals from a remote communication device, for example a radio receiver, a radio transponder or a telephone interface unit, and optionally a fourth input for receiving a signal from a tamper detector, eg in the meter, and/or a fluid leakage detector and/or a fire detector. Where said communication device is a two way communication device, the microprocessor may be arranged to supply said stored total quantity signal to the communication device for onward transmission by radio or telephone.

Each of said inputs is preferably arranged to receive a respective input connector which can be sealingly connected thereto, and the microprocessor is preferably arranged to close the valve in response to removal of an input connector. Additionally, each input may be arranged to receive a respective closure member as an alternative to its input connector, each closure member being sealingly connectable to its input, and the microprocessor being arranged to treat the presence of a closure member at an input as a valve opening signal from that input.

According to another aspect of the invention, there is provided a fluid flow control device for controlling the flow of fluid to a consumer, the device comprising an electrically-operable valve and a microprocessor for controlling the operation of the valve, the microprocessor having an input for receiving control signals from a remote communication device, for example a radio receiver, a radio transponder or a telephone interface unit, and being arranged to operate the valve in response to said control signals.

The invention will now be described, by way of example only, with reference to the accompanying drawing, which is a simplified block diagram of a gas flow control device in accordance with the present invention.

The gas flow control device shown in the drawings is indicated generally at 10, and comprises a solenoid-operated valve 12 adapted to be connected in series in a domestic gas supply pipe 14, and a microprocessor 16 for controlling the operation of the valve 12.

A diaphragm-type gas meter 18 is also connected in the pipe 14, upstream of the valve 12, the meter typically being of the known U6 type available from the Applicant. As is known, the meter 18 has an index mechanism 20, called an R5 index mechanism, which contains a reed relay (not shown) caused to periodically close by a magnet (not shown) rotatably driven by the index machanism at a rate proportional to the volumetric flow rate of the gas passing through the meter. The index mechanism 20 also has first and second output connections 22, 24 associated with this reed relay, by means of which first and second output signals respectively representative of the volumetric flow rate of the gas and of attempts to tamper with the meter by tilting it or placing a magnet next to the index mechanism 20 can be obtained.

The output connections 22, 24 are connected to first inputs 26, 28 of the microprocessor 16 by way of a first sealable connector 30 on the device 10: the term "sealable connector" as used herein means a connector in which the male and female parts can be sealed together, eg by a wire loop passing through both parts and sealed with a lead or plastics seal, so that the parts can be disconnected only by breaking the wire or seal.

The microprocessor 16 also has second inputs 32, to which the output of a prepayment unit 34 can be connected by way of a second sealable connector 36 on the device 10. The prepayment unit 34 comprises a receptacle 38 for receiving and making electrical contact with an electronic token 40, typically in the form of key containing a non-volatile memory such as an EEPROM, as described in our United Kingdom Patents Nos 2 153 573, 2 191 622 and 2 191 883, but equally possibly, in the form of a so-called smart card or a magnetic card. The prepayment unit 34 also includes an interface circuit 42 for interfacing between the token 40 and the microprocessor 16, and a display 44, typically a liquid crystal display (LCD).

The microprocessor can additionally have third inputs 46, to which a communication unit 48 can be connected by way of a third sealable connector 50 on the device 10. The unit 48 can be a radio receiver of the kind made by the Applicant under its designation "Radio Teleswitch", a radio transponder of the kind described in our United Kingdom Patent No 2 230 571 or a telephone interface unit of the kind available from the Applicant under its designation "Meter Interface Unit" (or MIU).

Additionally, the microprocessor 16 can also have fourth and fifth inputs 52, 54 respectively, to which a gas leakage detector 56 and a fire detector 58 can be respectively connected by way of fourth and fifth sealable connectors 60, 62 respectively on the device 10.

Finally, the device 10 includes an EEPROM 64 coupled to the microprocessor 16 and a long-life battery (not shown).

Over ten million U6 gas meters with R5 indexes are currently already installed in the United Kingdom, most of them serving as credit meters. In order to convert such an already installed meter into a prepayment meter for a particular consumer, the control device 10 is installed in the pipe 14 at a convenient location downstream of the meter as shown in the drawing, the prepayment unit 34 is also installed at a convenient location in the consumer's premises, and the meter 18, device 10 and unit 34 are connected together as shown in the drawing by way of the sealable connectors 30, 36, which are then sealed. The microprocessor 16 is programmed to perform the functions of a prepayment system of the kind described in our United Kingdom Patents Nos 2 153 573 and 2 191 622, so that the meter 18, the valve 10 and the prepayment unit 34 together constitute such a prepayment system. In particular, the microprocessor 16 receives and accumulates pulses representative of the volumetric flow rate of the gas passing through the meter 18, and data representative of a prepayment made by the consumer and the current gas supply tariff from the token 40 via the prepayment unit 34, and closes the valve 12 when a volume of gas equivalent in value at the current tariff to the prepayment (or otherwise related to the prepayment) has passed through the meter. Additionally, the microprocessor 16 periodically stores the accumulated total of the pulses received from the 18 in the EEPROM 64, so that its contents track the reading of the meter 18, and also drives the LCD 44 in the prepayment unit 34, causing it to display the amount of credit remaining unused, and if desired, the meter reading in the EEPROM 64.

The microprocessor 16 is also programmed to detect disconnection of either of the meter 18 or the prepayment unit 34, whether at the sealed connectors 30, 36 or elsewhere, and to close the valve 12 in response to such detection and to store a signal indicative of such detection in the EEPROM 64, as evidence of possible tampering with the system. Similarly, the microprocessor 16 closes the valve 12, and stores a further tamper signal in the EEPROM 64, if the microprocessor receives a tilt or magnetic tamper signal from the meter 18.

The communication unit 48, if connected, can be used in a number of ways. For example, it can be used to control the valve 12 either in conjunction with the meter 18 and the prepayment unit 34, or instead of the meter 18 and the prepayment unit 34.

In the first case, the communication unit 48, if a radio receiver (ie a one-way communication device), can be used to remotely close the valve 12 when the premises in which the device 10 is situated are vacated by one consumer prior to occupation by a new consumer. If the communication unit 48 is a radio transponder or a telephone interface unit (both two-way communication devices), it can additionally be used to remotely read the meter reading in the EEPROM 64 upon the vacation of the premises.

In the second case, the communication unit 48 can be used to form either an altemative kind of prepayment system, or a credit system, in which the valve 12 can be remotely closed if the consumer does not make specified payments by specified dates for the gas to be supplied or already supplied, and subsequently remotely re-opened when the consumer makes a payment.

The microprocessor 16 is programmed to close the valve 12 in response to signals indicative of a gas leak or of a fire from the detectors 56 and 58 respectively.

Each of the sealed connectors 30, 36, 50, 60, 62 is provided with a sealable closure member (not shown) for when it is not in use, the microprocessor 16 being arranged to treat the presence of a sealed closure member at an input as an open-enable signal for the valve 12 from that input.

Many modifications can be made to the described embodiment of the invention.

For example, the device 10 can be adapted to co-operate with gas meters other than diaphragm-type gas meters, eg ultrasonic gas meters, and with fluids other than gas, and it can be mounted upstream rather than downstream of the meter. Also, most if not all of the prepayment unit 34 andior the communication unit 48 can be incorporated in it. Additionally, the pulses representative of flow rate can in fact take the form of serial or parallel digital signals representative of actual meter readings, which the microprocessor processes to determine when an amount of gas determined by the available credit has been supplied, and continually stores the most recent in the EEPROM 64.

Claims

1. A fluid flow control device for controlling the flow of fluid to a consumer via a meter, the device comprising an electrically-operable valve and a microprocessor for controlling the operation of the valve, the microprocessor having a first input for receiving pulses representative of the flow rate of the fluid passing through the meter and a second input for receiving a data signal including data representative either of a prepayment made by the consumer and the fluid supply tariff or of a volume of the fluid equivalent in value to a prepayment made by the consumer, the microprocessor being arranged to close the valve when a volume of the fluid determined by the prepayment has passed through the meter.

2. A device as claimed in claim 1, wherein the microprocessor is arranged to accumulate said pulses to determine the total quantity of the gas which has passed through the meter, and the device further includes a non-volatile memory for storing a signal representative of said total quantity.

3. A device as claimed in claim 1 or claim 2, wherein the microprocessor has a third input for receiving control signals from a remote communication device.

4. A fluid flow control device for controlling the flow of fluid to a consumer, the device comprising an electrically-operable valve and a microprocessor for controlling the operation of the valve, the microprocessor having an input for receiving control signals from a remote communication device.

5. A device as claimed in claim 3 or claim 4, wherein said remote communication device is a radio receiver.

6. A device as claimed in claim 3 or claim 4, wherein said remote communication device is a radio transponder.

7. A device as claimed in claim 3 or claim 4, wherein said remote communication device is a telephone interface unit.

8. A device as claimed in claim 6 or claim 7, wherein the microprocessor is arranged to supply signals for onward transmission by said remote communication device.

9. A device as claimed in any preceding claim, wherein the microprocesor has a further input or inputs for receiving a signal from at least one detector selected from a tamper detector, a fluid leakage detector and a fire detector.

10. A device as claimed in any preceding claim, wherein the or each input is arranged to receive a respective input connector which can be sealingly connected thereto, and the microprocessor is arranged to close the valve in response to removal of an input connector.

11. A device as claimed in claim 10, wherein the or each each input is arranged to receive a respective closure member as an altemative to its input connector, the or each closure member being sealingly connectable to its input, and the microprocessor being arranged to treat the presence of a closure member at an input as a valve opening signal from that input.

12. A fluid flow control device substantially as herein described with reference to the accompanying drawing.