Rotary valve arranged in a multi -gas cooker

059 642 U

DESCRIPTION

Rotary valve mounted on a multi-gas cooking appliance.

Technical sector

The present invention relates to a gas tap of the conical regulating organ type coupled to a rotary drive shaft, and mounted on the panel of a cooking appliance, and with the means for adjusting the degree of flow according to the family fuel gas used.

Prior state of the art

Gas taps of the type defined above are known, provided with a dome-shaped bearing bush guiding the rotation of the drive shaft, and at the same time acting as a cover for the hollow body of the tap. The gas tap is mounted on the front panel of the controls with the drive shaft passing through a control panel outside the appliance, and the body of the tap inside the appliance connected to a fuel gas supply pipe. The free end of the drive shaft is mounted with a rotary knob inserted into the latter. The control button is removable from the shaft by pulling it outwards. The hollow body of the tap has its own gas outlet conduit that is connected to the corresponding burner of the appliance.

An example of a rotary tap of the above type is disclosed in GEP-0805310-A1 whose rotary drive shaft coupled to a frusto-conical regulator, which can rotate a certain angle to supply a gas flow from two spaced angular positions. between them around 110 ° - 120 °, which correspond respectively to a high flow or maximum flow "Qmax" and a low flow or minimum flow "Qmin", the latter applied to a "soft boil". Rotation to one of the angular positions starts from an initial position "OFF" of the closed valve.

In this type of known taps, the actuating shaft has a radially extended pin for limiting its angular travel, guided on a circular surface on the inner face of the cover of the body or of another part of the valve body. The total travel of the regulating member thus limited is for example 210 ° from the OFF position. The extreme position corresponds to Qmin. Any of the flow rates Qmax, Qint and Qmin is regulated through a corresponding orifice or slot of the regulating organ facing the outlet duct. All the degrees of flow are supplied from a common inlet in the internal chamber of the regulating organ. The outlet orifice of the Qmin has a sectional area calibrated for a certain type of fuel gas, proper to the power of the burner of the cooking appliance.

Solutions are known to allow a single tap to be mounted in cooking appliances that use two different types of gas, such as natural gas NG or liquefied petroleum gas LPG. In US-A-5009393, an additional valve element in the form of a sleeve inserted in the inner chamber of the conical regulator member is used for this. By rotating the latter, the area of ​​the gas passage section towards the outlet, corresponding to the low flow or minimum flow Qmin, is adjusted. The adjustment of the passage area is made by turning the valve sleeve to modify the free area or uncovered section of said outlet opening.

This known solution has the drawback that the screwdriver used to rotate the valve sleeve has to be applied from the opening of a plate associated with the control button, traversing the drive shaft in the axial direction until it reaches the valve sleeve. for adjusting the Qmin, and also transmitting a precise turn to the valve sleeve.

Presentation of the invention

The object of the invention is a gas tap for a domestic cooking appliance, of the truncated-conical regulating organ type coupled to an actuating shaft and a rotary control knob, which by means of its rotation is capable of supplying different flow rates of Precise gas between two limit angular positions, of any of the two different types of gas, N gas or LP gas, for which the tap has double means of limiting the angle of rotation, wherein the control button, being interchangeable on the drive shaft, is provided or not with a means for limiting the rotation, in cooperation with a means for limiting the rotation on a mounting panel of the cooking appliance, depending on the type of gas used by the appliance.

The gas valve according to the invention is capable of providing two angular positions of the regulating member spaced from each other, both to supply a different minimum flow depending on the type of normal NG or LPG gas typical of the supply to the apparatus. For this, the regulating member has two successive Qmin outlet orifices spaced in the rotational direction, which are positioned facing the outlet orifice respectively, by the rotational limitation means provided in the valve body cover and by the limitation means. rotational of different travel provided in the control button. The latter, in cooperation with the panel of the apparatus, provides an angular position of the regulating member for N gas, at a lower angle than that provided for LP gas by the rotational stops of the cover and of the drive shaft.

The use of a single valve to regulate the flow of two different gas families is an advantage of the invention of a gas valve mounted on a cooking appliance. During the start-up of the cooking appliance, the user only has to carry out a single and simple operation, choosing a control button from among two possible accessories from the valve accessories “kit”, according to the type of fuel gas N gas or LP gas suitable for the cooking appliance, and then fit the control knob by pushing it by hand on the actuating shaft. In this way, it is not necessary to use tools to adjust the flow, nor to learn an adjustment of the regulating member as required in the valve of the state of the art.

Description of the drawings

Figure 1 is a sectional view of a gas valve mounted on a panel of a cooking appliance according to the invention.

Figure 2 is a sectional view of the valve regulating member according to line II-II of Figure 1.

Figure 3 is a development view of the valve regulating member of Figure 2.

Figure 4 is a front view of the valve mounting panel according to Figure 1.

ES 1 059 642 U

Detailed description of an embodiment of the invention

With reference to Figures 1-4, an embodiment of gas cooking appliance 1, for example so-called barbecues, has a mounting panel 2 on which one or more rotary gas valves 3 of an existing general construction are mounted. . The cooking appliance 1 can be of two kinds relative to the type of gas used N-gas or LP-gas from an external source GAS IN. Each of the valves 3 is always of a unique class and they are mounted on panel 2. The valve 3 is connected to the GAS IN source through an inlet 4 in the valve body 3a, and the inlet flow is transmitted from an internal chamber 8 through the frusto-conical regulating member 6, which rotates around a central axis 10 of the valve thus supplying a flow "Q" through the outlet conduit 5, directed towards a burner of the appliance (not represented in the drawings) specifically adapted to one or another type of N gas or LP gas.

The valve body 3a is elongated in shape with a central housing cavity 15 also frusto-conical for the regulating member 6, the latter being pushed by a spring 11 for a tight closure. The actuating shaft 7 of the valve is coupled to the regulating member 6 for its rotation. The free end of the drive shaft 7 is mounted through a hole 2a in the panel of the apparatus, and subsequently the user incorporates a control button 9, chosen from two kinds of control buttons supplied with each valve unit 3. A cover 12 covers the cavity 15 housing the valve and extends with a tubular sleeve 12b on the drive shaft 7, to guide the latter in its rotation.

The regulating member 6 driven by the axis 7 can rotate an angle "A" in either of the two directions, normally up to an angle A greater than 180 ° and less than 360 °, from an initial angular position "OFF", in which valve 3 is closed. This OFF position constitutes a limit end of the travel of rotation "A", which is determined by a radial pin 13 on the drive shaft. The internal face of said cover 12 presents a sliding surface for the radial pin 13, extended in an arc of rotation "A3" up to a recess 12a that determines a limit of the angular travel of the axis 7.

Figures 2 and 3 show an example of the embodiment of the cooking appliance 1 described here. From an angular position OFF and in the clockwise direction, the frusto-conical member 6 regulates the supply of different gas flow rates "Qmax", "Qint" and "Qmin" as a function of the rotated angle "A". The minimum flow "Qmin" supplied to the outlet duct 5 in an N gas appliance must be greater than that supplied in an LP gas appliance for a burner of equal power in both cases. Valve 3 with its regulating member 6 is the same for mounting in either type of cooking appliance. One or another kind of device is distinguished by the control button 9 incorporated in the drive shaft. Once the user has identified cooking appliance class 1, he has chosen one of the two available control button units. The control button 9 represented in the apparatus of Fig. 1, is adapted for the supply of N gas (NG) and has an appendix 14 projecting from a base 9a of the control facing the panel 2. The second kind of control button, not shown in the drawings, is chosen for mounting in a cooking appliance using LPG.

With reference to Figures 2 and 3, the regulating member 6 rotates to an angular position A1 = 100 degrees, to supply a maximum flow rate "Qmax" of any NG or LPG gas in both kinds of cooking appliance 1. The flow rate Qmax is regulated by a hole 16 in the regulating member, when the latter is facing the outlet duct 5. If the rotation of the regulating member 6 continues, an intermediate flow "Qint" will be supplied through an opening 17 of decreasing area in the form of a slot .. The flow rate "Qinter" being less than the Qmax, it is descending as a function of the angle A. rotated, until it meets the outlet duct 5 in an angular position A2 = 210 degrees from a hole 18, of calibrated diameter D1 for a Qmin of NG.

In the NG class cooking appliance, the control knob provided with appendix 14 cannot rotate an angle greater than A2. The mounting panel 2 for the valve, (Fig. 4) has a circular groove 20 traversed by the appendix 14, the angular extension of which imposes the limit that the regulating member 6 has in the position A2 = 210 degrees. Since the control button unit 9, adapted to supply LPG, is mounted on the panel 2, it does not have an appendix 14 or any other element limiting the angle "A" of rotation, therefore the regulating member 6 can rotate to a position angular A3 = 270 degrees, more distanced from the initial OFF position than the previous position A2, until the confrontation is facing the outlet duct 5 of a second orifice 19 of Qmin of LPG.

The cover 12 of the valve body is provided with a tubular part 12b for guiding the valve shaft 7, and with a recess 12a for guiding a radial pin 13 limiting the angular travel A3 = 270 degrees. The cover 12 can be manufactured inexpensively by stamping operations alone. Equally low is the economic cost of molding two kinds of control button 9, with and without the stop appendix 14, the latter integral with the base 9a of the control button.

Other embodiments of the invention are possible in addition to that described above. Half of the units of the control button 9 of the kind applied to the NG appliance, can be provided with any stop means 14 integrated in the control button 9, and can interact with a part of the cooking appliance 1 associated with the panel 2, imposing another limit position A2 of rotation smaller than that imposed by the drive shaft itself. Likewise, the drive shaft 7, the same for all valve units 3, can have another means of abutment of the angular travel A3, and interact with a part of the valve body other than the cover 12, because its effect and advantage would be as follows. same that the invention discovers.

The arrangement of two stop means 12a and 20 on the valve body and on the panel 2 of the apparatus and the respective extension of their circular arches, corresponds to the two different total travels A2 and A3, and the angular space A3-A2 between the two respective outlet ports 18 and 19 in the regulating member 6, for the use of the same valve unit 3, without the need to make any adjustments, for the supply of both the constant minimum flow Qmin of LPG and NG.