The invention relates to a gas valve unit for setting a gas volumetric flow that is fed to a gas burner of a gas appliance, in particular a gas cooking appliance.
Gas valve units of said type are described for example in EP0818655A2 and W02004063629 A1. Such gas valve units can be used to control the gas volumetric flow fed to a gas burner of a gas cooking appliance in a number of stages. The gas volumetric flow is then of a reproducible size in each stage. The throughflow cross section of the gas valve unit as a whole and therefore the size of the gas volumetric flow are set by opening or closing certain open/close valves of the gas valve unit, thereby allowing or preventing the gas flow through certain throttle openings.
A gas conversion option is also described in the patent application “Structure of a gas valve unit” (201002677), which had not yet been published at the date of this application. If gas conversion is required with such a gas valve unit, a cover plate must be released and removed from the valve housing of the gas valve unit. As the connection between the valve housing and the cover plate is released, the valve bodies press against the sealing plate, thereby allowing air into the system, so that it can be removed easily from the valve housing. The handle shaft remains connected to the valve housing in a fixed manner in this process. When the cover plate has been removed, it is possible to take away the sealing plate, the pressure plate and the lower gas distribution plate as individual plates or as a composite plate.
Present in the cover plate is an opening, which allows control of the nozzle plate used. Slight pressure through said opening onto the nozzle plate causes the nozzle plate including the sealing composite plate to be pressed out of the cover plate attachments. The upper gas distribution plate can remain in the cover plate. The nozzle plate can then be removed and replaced for the conversion. Corresponding geometries of the components only allow one incorporation option. The plates are replaced in the cover plate in reverse order. This solution has the disadvantage that the cover plate must be disassembled before the change of gas type and must be reassembled after the change of gas type.
The object of the present invention is to provide a gas valve unit of the type mentioned in the introduction, with which components do not have to be disassembled for gas conversion.
According to the invention this object is achieved in that the gas valve unit has a plurality N of individually actuatable throttle sections arranged in parallel for setting the throughflow rate of the gas volumetric flow.
The plurality of throttle sections arranged in parallel allows different throughflow rates to be set, in particular as a function of the different gas types.
In this process the throttle sections are combined appropriately in different ways by activating or deactivating the individual actuatable throttle sections for gas conversion.
For example it is no longer necessary to replace nozzle plates when converting from natural gas to liquefied gas. It is also possible to dispense with at least one type of nozzle plate, as multiple use is possible within the nozzle plate. Because nozzle plate replacement is not required and the fitting therefore does not have to be opened, no seal check has to be performed. It is also not necessary to disassemble the switch strip of the gas valve unit for this reason. The plurality of possible combinations of throttle sections means that it is possible to set predefined gradations as required and thus to achieve the necessary settings for any gas type. If for example the standard gradation is too imprecise for the user or customer in the low output range, it is possible to set a more precise gradation in the low output range with the aid of a different throttle section or a different combination of throttle sections.
In one preferred embodiment the respective throttle section has a plurality M of throttle points arranged in series.
The throttle point can also be referred to as a throttle element, control element or control device.
In one preferred embodiment the throttle points arranged in series have an opening cross section that increases along the line.
It is thus possible to increase the connected load according to the rotation angle of the actuation shaft. For example when converting back from liquefied gas to natural gas it is possible to achieve exact throughflow values by means of the defined opening cross sections.
In a further preferred embodiment the respective throttle section has a throttle section switch for activating and deactivating the throttle section.
The respective throttle section can be activated or deactivated by means of the respective throttle section switch.
In one preferred embodiment the respective throttle section has a plurality M of throttle points arranged in series and a throttle section switch connected downstream of the throttle points to activate and deactivate the throttle section.
In a further preferred embodiment a trigger facility is provided to trigger the N throttle section switches. The trigger facility is set up to select a certain trigger profile of a plurality of predetermined trigger profiles for triggering the N throttle section switches as a function of a gas type to be used. The trigger facility will also trigger the N throttle section switches with the selected trigger profile.
The throughflow rate of the gas volumetric flow required for the respective gas type can therefore be set automatically by the trigger facility.
In one preferred embodiment the gas valve unit has a plurality M of valve units. The ith valve unit here is set up to trigger the ith throttle points of the throttle sections (i∈[1, . . . , M]).
This means for example that all the first throttle points of the throttle sections are triggered by the first valve unit, in particular are triggered at the same time.
In a further preferred embodiment the respective valve unit has a number N of open/close valves. Here the jth open/close valve is set up to trigger the jth throttle section (j∈[1, . . . , N]). When the open/close valve is closed, it rests on a valve seat. This closes an opening in the valve seat. The valve seats of the open/close valves can be formed by a common component, which is preferably formed by a valve sealing plate.
In a further preferred embodiment the N open/close valves of the respective valve unit can be actuated at the same time by actuating a control apparatus. The control apparatus is formed for example by a movable, magnetically active body, in particular by a permanent magnet. To open the open/close valve the blocking body is raised from the valve seat by means of the force of the permanent magnet arranged above or below the open/close valve counter to the force of the spring.
In the following the term “permanent magnet” is also used to represent other magnetically active bodies. If the movement of the permanent magnet is brought about manually by an operator, no electrical components are required to switch the valve units, in particular the open/close valves of the valve units. Alternatively the permanent magnet can also be moved by means of any actuator, for example an electric motor. The electric motor here is triggered by an electrical control unit or control apparatus. This control unit allows the same gas valve unit to be actuated mechanically by the operator or by means of an electrical actuator as required. During the production of cooking appliances gas valve units of identical structure can be combined both with mechanical user interfaces, for example rotary knobs, and also with electrical user interfaces, for example touch sensors.
In one preferred embodiment the N open/close valves of the respective valve unit are formed by a blocking body, a spring acting on the blocking body and a number of separating walls to feed the gas volumetric flow to the N throttle sections.
In a further preferred embodiment the N valve units can be activated in an additive manner by moving at least one magnetically active body, in particular a permanent magnet, relative to the valve units.
In a further preferred embodiment a conversion facility for gas conversion is arranged in the region of the actuation shaft of the gas valve unit. The conversion facility is configured as a screw for example. The screw for converting the gas types can be positioned more centrally on the handle shaft than with cone fittings.
The gas valve unit is in particular part of a manually actuated multiple position device consisting of a valve part and an adapted ignition protection. Integrated in the valve part are in particular a handle or rotary knob, permanent magnets, valves, nozzles and seals. The handle can be pressed in by light pressure and this actuates the ignition protection. The open/close valves or ferrite valves are pressed onto seals in one or more gas-tight chambers by one or more resilient components, thereby preventing the throughflow to the associated openings or seal openings. The resilient components or springs are held in a cover that it positioned in a gas-tight manner.
A gas fitting for a gas appliance is also proposed, which has at least one gas valve unit as described above.
A gas appliance is also proposed, which has a gas fitting as described above. The gas appliance is for example a gas oven.
Further advantages and details of the invention are described in more detail based on the exemplary embodiments illustrated in the schematic figures, in which:
The gas valve unit has a plurality N of individually actuatable throttle sections 3, 4, 5 arranged in parallel for setting the throughflow rate of the gas volumetric flow. The parallel throttle sections 3, 4, 5 are arranged between the gas input 1 and the gas output 2. N=3 in
The respective throttle section 3, 4, 5 has a number M of throttle points 3.1-3.4, 4.1-4.4, 5.1-5.4 arranged in series. M=4 in
The respective throttle section 3, 4, 5 also has a throttle section switch 3.5, 4.5, 5.5 to activate and deactivate the corresponding throttle section 3, 4, 5. For example the first throttle section switch 3.5 is set up to activate and deactivate the first throttle section 3.
A trigger facility (not shown) in particular is provided to trigger the throttle section switches 3.5, 4.5, 5.5. The trigger facility is set up to select a certain trigger profile of a plurality of predetermined trigger profiles to trigger the throttle section switches 3.5, 4.5, 5.5 as a function of a gas type to be used and to trigger the throttle section switches 3.5, 4.5, 5.5 correspondingly with the selected trigger profile.
The gas valve unit also has a main throttle point 7 arranged downstream of the parallel throttle sections 3, 4, 5 and a main valve unit 8 arranged parallel to the throttle sections 3, 4, 5. The main valve unit 8 can also be referred to as a main switching device.
The gas valve unit also has a plurality M of valve units 6.1, 6.2, 6.3, 6.4 (M=4). As mentioned above N=3 in
In the example in
In
To summarize, the exemplary switching arrangement of the gas valve unit in
The throttle point 3.4 of the throttle section 3 can be closed with a throttle section switch 3.5 and also connects the last connecting segment 3.9 to the gas output 2.
The open/close valves 6.1.1-6.1.5 are actuated in particular by means of a permanent magnet 11, which can be displaced along the line of open/close valves 6.1.1-6.1.5. The force for opening the respective open/close valve 6.1.1-6.1.5 is formed directly by the magnetic force of the permanent magnet 11 here. This magnetic force opens the respective open/close valve 6.1.1-6.1.5 counter to the spring force of the spring 13.
In the switching position according to
Gas is supplied to the first connecting segment 3.6 and 4.6 almost exclusively by way of the second open/close valve 6.1.2. Because the open/close valves 6.1.1 and 6.1.2 are open, the same pressure level prevails in the input segments 3.10 and 4.10 as in the first connecting segments 3.6 and 4.6. Virtually no gas then flows out of the input segments 3.10 and 4.10 by way of the first throttle points 3.1 and 4.1 into the first connecting segments 3.6 and 4.6. The gas volumetric flow flowing as a whole through the gas valve unit therefore remains virtually the same when the permanent magnet 11 is moved further to the right in the drawing, causing the first open/close valve 6.1.1 to close while the second open/close valve 6.1.2 remains open. Moving the permanent magnet 11 to the right in the drawing causes the open/close valves 6.1.3-6.1.5 to open successively. This increases the gas volumetric flow through the gas valve unit in steps.
The gas from the gas input 1 flows through the open second open/close valve 6.1.2 directly into the first connecting segment 4.6 and from there by way of the throttle points 4.2-4.4 to the gas output 2. The other gas path leads from the open/close valve 6.1.2 into the first connecting segment 3.6 of the first throttle section 3 and from there by way of the throttle points 3.2-3.4. However the throttle point 3.4 is closed by the throttle section switch 3.5 so no further gas can flow to the gas output 2 by way of the connecting segment 3.9.
The gas flowing to the gas output 2 bypasses the first throttle points 3.1 and 4.1 because of the open open/close valve 6.1.2. The gas volumetric flow in the switching position according to
In the example in
During switching from one open/close valve 6.1.1-6.1.4 to an adjacent open/close valve 6.1.2-6.1.5, both adjacent open/close valves 6.1.1-6.1.5 are open for a short period. This ensures that switching does not result in brief interruption of the gas supply to the gas burner and therefore flickering or extinguishing of the flames. The switching position described above also ensures that the gas volumetric flow does not increase briefly during a switching operation. This also reliably prevents flaring of the gas flames during the switching operation.
1 Gas input
2 Gas output
3 First throttle section
3.1-3.4 Throttle points of the first throttle section
3.5 Throttle section switch of the first throttle section
3.6-3.9 Connecting segment
3.10 Input segment
4 Second throttle section
4.1-4.4 Throttle points of the second throttle section
4.5 Throttle section switch of the second throttle section
4.6-4.9 Connecting segment
4.10 Input segment
5 Third throttle section
5.1-5.4 Throttle points of the third throttle section
5.5 Throttle section switch of the third throttle section
6.1 First valve unit
6.1.1-6.1.5 Open/close valve
6.2 Second valve unit
6.2.1-6.2.3 Open/close valve
6.3 Third valve unit
6.3.1-6.3.3 Open/close valve
6.4 Fourth valve unit
6.4.1-6.4.4 Open/close valve
7 Main throttle point
8 Main valve unit
9.1-9.8 Separating wall
10 Gas input chamber
11 Permanent magnet
12 Blocking body
13 Spring
14 Cover plate
15 Sealing composite plate
15.1 Sealing plate
15.2 Pressure plate
15.3 Lower gas distribution plate
16 Upper gas distribution plate
17 Low combustion position
18 Path
19 Screw
20 Opening for actuation shaft
21 Full combustion valve
22 Nozzle plate
Number | Date | Country | Kind |
---|---|---|---|
11290418.0 | Sep 2011 | EP | regional |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2012/067191 | 9/4/2012 | WO | 00 | 2/26/2014 |