GB2029564A

GB2029564A - Improvements in or relating to gas burner control assemblies.

Info

Publication number: GB2029564A
Application number: GB7929720A
Authority: GB
Original assignee: Karl Dungs GmbH and Co KG
Current assignee: Karl Dungs GmbH and Co KG
Priority date: 1978-08-30
Filing date: 1979-08-28
Publication date: 1980-03-19
Also published as: NL188118C; IT7925352A0; NL7906435A; FR2434998B1; IT1122887B; GB2029564B; CH642436A5; DE7825759U1; IT7922381V0; NL188118B; FR2434998A1

Abstract

An operational control assembly for installation in a gas feed pipe of a gas burner comprises a plurality of devices 1, 2, 3 for controlling gas flow, regulating the gas pressure, filtering the gas stream, or an alternative control function. Each device has a body with an inlet and an outlet in respective faces at opposite sides thereof. Connecting means serially interconnect the devices with adjacent inlet and outlet faces in sealing engagement and the respective inlets and outlets in registering relationship. <IMAGE>

Description

SPECIFICATION Improvements in or relating to gas burner control assemblies This invention relates to an operational control assembly for installation in a gas feed pipe of a gas burner.

Gas burners in heating and combustion installations are customarily preceded by a plurality of devices which ensure the reliable operation of the burner with the desired heating power. Thus the burner will be preceded by at least one valve which opens or closes the gas supply. Also, since the gas pressure in the feed pipe may fluctuate, and a fluctuating gas pressure can severely influence the burning properties and the burner efficiency, the gas burner is preceded by a regulator which converts the high fluctuating pressure prevailing in the pipe, to a lower at least approximately constant pressure.

Finally these devices are frequently also preceded by a filter which protects them against particles entrained by the gas stream which might adversely influence the functioning of the regulator, valve and burner.

During installation of a gas burner, these devices are individually built into the gas feed pipe in appropriate sequence. This involves considerable assembly work on site which is very undesirable in view of high labour costs and frequent shortages of skilled workmen.

It is an object of the present invention to provide an operational control assembly for installation in a gas feed pipe of a gas burner whereby the above disadvantages are obviated or mitigated.

According to the invention, the assembly is a device combination which consists of individual devices which are securely connected together in the works, and for this purpose the casings comprise two inlet and outlet surfaces which are parallel to each other and which fit together in respective pairs, and all the device casings are provided with fixing means for mutual connection.

Considerable costs can be saved by the use of such an assembly because the various devices can more easily be assembled in the works by mass production techniques than on site. Furthermore, not only is the work of fitting connecting pipes between the individual devices on site avoided, thus considerably reducing installation costs, but also the construction of the combustion installation fitted wiih which an assembly is simplified and better adapted to effective supervision.

The employment of a device assembly according to the invention permits a further advantage to be obtained. In many installations of this kind a leakage test is performed in the following manner. Two valves are connected in series along the flow direction and the volume between the two valves is subjected to a pressure which is increased or reduced relative to the normal pressure. By means of a pressure monitor or pressure meter forming part of a leakage control device the time taken for pressureequalisation is measured. If the leak tight ness is sufficient, the return to normal pressure occurs very slowly. The period of time for the equalisation is thus a measure for the leak tightness.

However, in conventional installations this period of time is very different from installation to installation, because it depends directly upon the volume of gas enclosed between the two valves. However, if an assembly according to the invention is used, this volume can be adjusted to a fixed value in the works from the outset quantity, so that a fixed time value which need not be determined for each individual installation can be stated for the leak tightness control.

In a preferred embodiment of the invention the casings have a similar contour in a plane perpendicularto the gas flow direction. This permits a simple assembly operation. In this case the fixing means are preferably constructed as continuous clamping screws. In this case the filter which is arranged at the inlet of the device combination is provided with screw-threaded bores for the clamping screws serving as fixing means. The side of the casings of the individual devices facing the filter are provided with protection means against release of the fixing means, for exampled formed-in holders for a nut.

In a particularly preferred further embodiment of this invention, the inlet and outlet faces of the casings are constructed as flange connections which are directly connectable to each other with the interposition of a seal. This permits a particularly space-saving and simple construction. The casings comprise simple corresponding plane faces at the mutually facing or abutting faces which are pressed one against the other with the interposition of seals.

Thereby a very compact device combination is obtained without additional connecting elements located therebetween. The device combination constructed in this manner does not only avoid unnecessary constructional elements, but may also be assembled together very simply in any desired combination of the individual devices.

In a preferred constructional form of the invention, a lateral connector for a pressure guard for leak tightness control is provided in one of the casings at a location situated between two valve seats of the device combination. In the manner described above, this permits a leak tightness control to be performed with standardised values.

In a particularly preferred constructional form of the invention an attachment flange is provided at the device combination; the flange side thereof is attached to the inlet or outlet face of the first or the last device, respectively, of the device combination, and the free side thereof is provided with a tube connector. Thereby the device combination may be connected in the simplest manner to the gas feed pipe on the one hand and to a tube leading to the burner on the other hand.

The invention will be further described by way of example only with reference to the accompanying drawings, in which: Figure 1 is a diagrammatic side view of one embodiment of operational control assembly according to the invention; Figure 2 is a section on the line ll-ll in Figure 1; Figure 3 is a view in the direction of the arrow Ill of Figure 1, enlarged in the same way as Figure 2 in relation to Figure 1.

Referring now to the drawings, the exemplary assembly comprises a filter 1, an electro-magnetic valve 2, an electro-magnetic valve 3 and a pressure regulator 4. Gas flows in the direction from the filter 1 to the pressure regulator 4.

The casings of all the devices 1 to 4 have the same, approximately square cross-section. The volume free of inserts, such as valve seats and the like, has provided therein continuous longitudinal bores for clamping screws 5 serving as fixing means. In this case the outlet side. (facing the burner) of each device 1 to 4 has a countersunk bore 6 for receiving the head of an Imbus screw, whereas the opposite, inlet side (facing the gas supply) has a hexagonal recess 11 for receiving a correspondingly shaped nut into which the respective clamping screw 5 is screwed.Otherwise the inlet and outlet side faces of the casings of the devices 1 to 4 are plane faces which with the interposition of gaskets (not illustrated) are clamped together by means of the clamping screws 5 and the nuts 6 to form an operational control assembly for the gas burner.

Furthermore, four screw-threaded bores are provided on both inlet and outlet side faces of the casings of all the devices 1 to 4 and fixing screws 7 are screwed into them which serve for fixing an attachment flange 8. One flange 8 is screwed to the inlet side face and another to the outlet side face of the assembly. Each attachment flange 8 comprises a cylindrical socket 9 which is threaded for screw connection to feed or discharge pipe sections between which the assembly is to be installed.

It will be appreciated that the invention is not limited to the-constructional example illustrated, but that deviations therefrom are possible without departing from the scope of the invention. In particular, individual features of the invention may be employed alone or in combination. For example, the casings may have cross-sections other than square, and the fixing means may be arranged differently, in which case care must be taken that the individual devices can be built together in any desired succession to form an assembly.

Preferably at least one of the two magnetic valves 2 or 3 is provided with a lateral access bore 10 which serves for the connection of a pressure monitor or pressure measuring device which is part of a leakage control device for performing a leakage test when the magnetic valves 2 and 3 are closed.

Claims

1. An operational control assembly for installation in a gas feed pipe of a gas burner, comprising a plurality of devices for controlling gas flow, regulating the gas pressure, filtering the gas stream, or an alternative control function, each device having a body with an inlet and an outlet in respective faces at opposite sides thereof, and connecting means serially interconnecting the devices with adjacent inlet and outlet faces in sealing engagement and the respective inlets and outlets in registering relationship.

2. An assembly as claimed in claim 1, wherein the inlet and outlet faces of each device are parallel to each other.

3. An assembly as claimed in claim 1 or 2, wherein the bodies of the devices are of like cross section correspondng to the shape of the inlet and outlet faces.

4. An assembly as claimed in any one of claims 1 to 3, wherein the connecting means comprise clamping screws extending continuously through the component devices.

5. An assembly as claimed in any one of the preceding claims, wherein a device for filtering the gas stream is provided at the upstream end of the assembly and has screw threaded bores for screw connection with the connecting means.

6. An assembly as claimed in any one of the preceding claims, wherein protection means are provided in the side of the bodies of the individual devices facing the filter, against release of the connecting means, for example holders formed therein for a nut.

7. An assembly as claimed in any one of the preceding claims, wherein the inlet and outlet faces of the bodies are constructed as flange connections which are directly connected together with the interposition of a seal.

8. An assembly as claimed in any one of the preceding claims, wherein a lateral connector for a pressure monitor is provided for leak tightness control in one of the bodies at a location between two valve seats of the assembly.

9. An assembly as claimed in any one of the preceding claims, wherein an attachment flange is provided the flange side of which is attached to the inlet or outlet face of the first or the last device, respectively, of the assembly and the free side of which is provided with a pipe connector.

10. An operational control assembly for installation in a gas feed pipe of a gas burner, substantially as herein described, with reference to and as illustrated in the accompanying drawings.