GB2275985A - Flow controller - Google Patents

Flow controller Download PDF

Info

Publication number
GB2275985A
GB2275985A GB9305135A GB9305135A GB2275985A GB 2275985 A GB2275985 A GB 2275985A GB 9305135 A GB9305135 A GB 9305135A GB 9305135 A GB9305135 A GB 9305135A GB 2275985 A GB2275985 A GB 2275985A
Authority
GB
Grant status
Application
Patent type
Prior art keywords
flow
governor
valve
flow line
line
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB9305135A
Other versions
GB2275985C (en )
GB2275985B (en )
GB9305135D0 (en )
Inventor
Brian Paul Foster
Aidan John Murray
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
HAMWORTHY HEATING Ltd
Original Assignee
HAMWORTHY HEATING LTD
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date

Links

Classifications

    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05DSYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D7/00Control of flow
    • G05D7/01Control of flow without auxiliary power

Description

2275985 FLOW CONTROLLER This invention relates to a controller for

controlling the flow of a fluid. Particularly, but not exclusively, the invention relates to a flow controller suitable for controlling fuel input into a furnace or boiler.

In order to control fuel input into a furnace or boiler, for example, it is known to use manual or automatic valves. It has been found that the most economical method of control makes use of a so-called "compact gas valve", which typically incorporates two solenoid valves and a springtype governor which are all arranged in series. This arrangement is housed in a single assembly (often termed a 11multifunctional11 assembly). Such assemblies are manufactured in very high numbers and are generally used in the domestic or commercial markets.

Although these valve assemblies are suitable for a wide variety of uses, they are limited in size and cannot normally exceed flow rates of 6.5m 3 /hr at a pressure loss of 2.5mbar.

If larger flow rates are required, one normally has to resort to valves which are intended for the industrial market. These valves are as much as four to five times 2 the cost of the above described type of compact valve as s embl y.

It has been suggested that to overcome the problem of economically increasing flow rate, two of the above described compact valve units should be arranged in parallel. However, it has been found that in practical terms this does not work, because the two governors tend to fight one another. The effect of this is that undesirably complicated consideration needs to be given to, inter alia, which governor should lead or lag. This makes setting up the system very difficult, if not impossible.

The present invention sets out to provide a flow controller which enables higher gas flows to be passed through small, inexpensive valves, whilst maintaining downstream pressure under control.

According to the invention there is provided a flow controller comprising an input, a first flow line, a second flow line arranged in parallel with the first flow line and an output; the first flow line comprising a valve and a governor arranged in series and the second flow line comprising a valve; the arrangement being such that, during use, the governor controls the flow rate through both valves.

3 Gas flow rate is controlled by adjusting the governor to give a specific pressure drop across an orifice at the outlet fitted downstream of the governed valve. If the upstream pressure increases (thereby forcing more gas through the ungoverned valve), the downstream pressure increases across the orifice. The governor detects this and moves to increase its internal pressure drop. Therefore, the governed gas will be closed down, thereby reducing the overall gas flow until the correct pressure drop is achieved.

Preferably, each flow line will comprise two valves arranged in series.

Preferably, the two valves and governor provided in the first flow line form part of a first type of compact valve assembly and the two valves provided in the second line form part of a second type of compact valve assembly.

The invention can be employed for use with large, commercial gas-fired boilers. It has been found that, by making use of an embodiment of the invention, the overall cost of the control system can be reduced by up to 50%.

4 The invention will be described by way of example and with reference to the accompanying drawings in which:- Figure 1 is a view of a flow controller according to the present invention; and Figure 2 is a schematic view of the flow controller of Figure 1 in position in a fluid supply.

Figure 1 shows an inlet 4 connected in series with a pair of parallel flow lines 8,10. One of the flow lines 8 comprises a governor valve assembly 9 and the other of the flow lines 10 comprises a by-pass valve assembly 11. The outputs from the two valve assemblies are combined and directed towards a common output 6_.

Figure 2 schematically shows the arrangement. Prom this figure, it can be seen that the governor valve assembly 9 comprises a valve 12 and a governor 16 arranged in series. The by-pass valve assembly 11 comprises a valve 14, but not a governor. Each of the valves 12,14 is a solenoid valve and the governor 16 is a spring-type governor. Ideally, each valve assembly is a compact valve assembly. Of course, alternative types of valve or governor can be used in order to suit the circumstances.

In the arrangement shown in Figures 1 and 2, each of the valves is, in fact, a pair of shut-off valves arranged in series in order to maximise safety. However, in each case a single valve could be used instead, if so desired.

During use, the controller monitors the downstream pressure and controls it should any variation in upstream pressure occur.

The governor'will attempt to control flow through itself in order to maintain downstream pressure. The line which comprises the by-pass assembly 10 is non-dynamic and any increase in inlet pressure would normally result in an increase in flow on the basis of the square law principle. However, an increase in flow results in an increase in downstream pressure. The governor monitors the increase in downstream pressure and reduces flow through the governor valve assembly, thus bringing the total flow through the assembly back to the desired level.

The way this works can be explained as follows. Gas flow rate is controlled by adjusting the governor to give a specific pressure drop across an orifice at the outlet fitted downstream of the governed valve.

If the upstream pressure increases (thereby forcing more 6 gas through the ungoverned valve), the downstream pressure increases across the orifice. The governor detects this and moves to increase its internal pressure drop. Therefore, the governed gas value will be closed down, thereby reducing the overall gas flow until the correct pressure drop is achieved. This function also works in reverse: if the upstream pressure decreases then the downstream pressure across the orifice will drop. This will cause the governor to open the governed valve until the required outlet pressure is achieved.

As a modification, the governor valve assembly can comprise a governor which is incorporated into the valve, if desired.

Many further modifications and adaptations will suggest themselves to those versed in the art upon making reference to the foregoing, which is given by way of example only and is not intended to limit the scope of the invention in any way.

Claims (6)

7 CLAIMS
1. A flow controller comprising an input, a first flow line, a second flow line arranged in parallel with the first flow line and an output; the first flow line comprising a valve and a governor arranged in series and the second flow line comprising a valve; the arrangement being such that, during use, the governor controls the flow rate through both valves.
2. A flow controller according to Claim 1, wherein each flow line comprises two valves arranged in series.
3. A flow controller according to Claim 1 or 2, wherein each flow line is at least partially defined by a respective compact valve assembly.
4. A flow controller according to any preceding claim, wherein the governor is a spring-type governor.
5. A flow controller according to any preceding claim, wherein the governor is incorporated into the valve in the first line.
6. A flow controller substantially as herein described with reference to Figure 1 or Figure 2 of the accompanying drawings.
6. A flow controller substantially as herein described with reference to Figure 1 or Figure 2 of the accompanying drawings.
Amendments to the claims have been filed as follows 0 0 CLAIMS 1. A flow controller comprising an input, a first flow line, a second flow line arranged in parallel with the first flow line and an output; the first flow line comprising a valve and a governor arranged in series and the second flow line comprising a valve; the arrangement being such that, during use, the governor monitors pressure downstream of the governor and, on the basis of the monitored downstream pressure, controls the flow rate through the valve in the first flow line, so as to maintain a required total outlet pressure.
2. A flow controller according to Claim 1, wherein each flow line comprises two valves arranged in series.
3. A flow controller according to Claim 1 or 2, wherein each flow line is at least partially defined by a respective compact valve assembly.
4. A flow controller according to any preceding claim, wherein the governor is a spring-type governor.
5. A flow controller according to any preceding claim, wherein the governor is incorporated into the valve in the first line.
GB9305135A 1993-03-12 1993-03-12 Flow controller Expired - Fee Related GB2275985C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB9305135A GB2275985C (en) 1993-03-12 1993-03-12 Flow controller

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB9305135A GB2275985C (en) 1993-03-12 1993-03-12 Flow controller
DE19944408452 DE4408452A1 (en) 1993-03-12 1994-03-12 flow regulator

Publications (4)

Publication Number Publication Date
GB9305135D0 GB9305135D0 (en) 1993-04-28
GB2275985A true true GB2275985A (en) 1994-09-14
GB2275985B GB2275985B (en) 1995-04-12
GB2275985C GB2275985C (en) 1996-06-04

Family

ID=10731962

Family Applications (1)

Application Number Title Priority Date Filing Date
GB9305135A Expired - Fee Related GB2275985C (en) 1993-03-12 1993-03-12 Flow controller

Country Status (2)

Country Link
DE (1) DE4408452A1 (en)
GB (1) GB2275985C (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2316463A (en) * 1996-08-15 1998-02-25 Honeywell Control Syst Flow control
US20100132692A1 (en) * 2008-12-01 2010-06-03 Timothy Scott Shaffer Gas grill
FR3026756A1 (en) * 2014-10-03 2016-04-08 Ahmed Ousedrat liquid dispensing system intermittently

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4148311A (en) * 1975-05-06 1979-04-10 The Secretary Of State For Defence In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern Ireland Gas mixing apparatus
US4617953A (en) * 1984-11-13 1986-10-21 Kendall Tobias Michael W Fluid flow control system

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4148311A (en) * 1975-05-06 1979-04-10 The Secretary Of State For Defence In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern Ireland Gas mixing apparatus
US4617953A (en) * 1984-11-13 1986-10-21 Kendall Tobias Michael W Fluid flow control system

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2316463A (en) * 1996-08-15 1998-02-25 Honeywell Control Syst Flow control
GB2316463B (en) * 1996-08-15 2000-07-05 Honeywell Control Syst Flow control
US20100132692A1 (en) * 2008-12-01 2010-06-03 Timothy Scott Shaffer Gas grill
US8863734B2 (en) * 2008-12-01 2014-10-21 General Electric Company Gas grill
FR3026756A1 (en) * 2014-10-03 2016-04-08 Ahmed Ousedrat liquid dispensing system intermittently

Also Published As

Publication number Publication date Type
GB2275985C (en) 1996-06-04 grant
GB2275985B (en) 1995-04-12 grant
DE4408452A1 (en) 1994-09-15 application
GB9305135D0 (en) 1993-04-28 grant

Similar Documents

Publication Publication Date Title
US5348076A (en) Cooling apparatus for electronic system
US4674678A (en) Mixing fixture for plumbing
US3729051A (en) Process fluid flow regulation systems
US6418956B1 (en) Pressure controller
US4699173A (en) Mixing and proportioning device for flowing media
EP0915241A2 (en) Fuel flow shut-off system
US3918480A (en) Device for feeding gases to a flame cutting machine
US4150788A (en) Remote-controlled central air-conditioning system
US5789879A (en) Multiple pump hydraulic power system
US6263908B1 (en) Slow opening gas valve
WO1999023544A1 (en) Pilot valve
US4863100A (en) Electronic flow controller for hydronic heating systems
US5699665A (en) Control system with induced load isolation and relief
US4790352A (en) Slow opening and fast closure gas valve
US4250908A (en) Flow control device
US4640093A (en) Fuel metering system
WO2005088194A1 (en) A valve unit for cotrolling the supply of a fuel gas, particularly for cooking hobs and the like
US3470896A (en) Parallel line fluid system with meter regulating valve
US3929281A (en) Fluid mixing valves
US20010022079A1 (en) Device and process for controlling the pressure and delivery of a fuel feed to a servovalve unit
US3502101A (en) Thermostatic control device with a pressure regulated stepped opened diaphragm valve
US4736582A (en) Gas turbine engine fuel control system
CN201376921Y (en) Multi-channel paratactic combination feed-water automatic oxygenation device for power plant boiler
US3391866A (en) Burner control system
US3991569A (en) Fuel control system for gas turbine engine

Legal Events

Date Code Title Description
727 Application made for amendment of specification (sect. 27/1977)
727A Application for amendment of specification now open to opposition (sect. 27/1977)
SP Amendment (slips) printed
727B Case decided by the comptroller ** specification amended (sect. 27/1977)
PCNP Patent ceased through non-payment of renewal fee

Effective date: 20090312