FR2503316A1 - Gas cock with turning shaft - has gas passage section independent of axial load of turning shaft - Google Patents

Abstract

The valve has a turning shaft (1), with a slightly conical working surface, displaceable in rotation in the body (2) of the valve. At the interface of the shaft and the body, two passages are provided for the flow of gas, controlled by the cooperation of a first opening (10) situated on one side of the interface with two second openings (11) on the other side of the interface. The three openings are such shaped so that the sections of the two passages decrease when the shaft is turned from fully open to a decreased flow position.

Description

Improvements made to ball or rotary valves, in particular to gas valves
The invention relates to ball valves or rotary valves, in particular gas, in particular for household appliances.

 It is common to make these valves understand, in addition to the full throttle position, an idle position, often obtained by continuing to operate the valve turn in the opening direction, to bring it to an extreme position being therefore beyond the normal opening position.

 It is also known to use, to ensure the progressiveness of the idling, a groove extending, at the surface of the turning point of the tap, the orifice for the passage of the gas, thereby ensuring a path between said orifice for passage of the turning point and 11 corresponding fixed orifice of the valve body, when these two orifices move away from one another, in particular during the complementary stroke beyond the normal open position. The progressiveness of the idling and the idle flow itself are then a function of the shape of the end of the groove and of its position relative to the edges of the fixed orifice.

 However, in known embodiments, it has been found that, for positions taken angularly by the turn in the idle position and close to this position, the two conditions, form of the corresponding end of the groove and position of the groove with respect to the fixed orifice, were dependent on the axial position of the turning point in the body of the valve. They would not vary if this position were immutable, but it cannot be prevented, within the accepted tolerance range, that the depression of the turn in said body - in particular in the case, considered below, of conical turns, held coaxially in place by a spring - does not give rise in practice to certain deviations and determines more or less passage sections less important from one tap to another, for a given angular position of the turn.

 It is then necessary, during the manufacture of known valves, to match the valve bodies and the turns so as to be ensured that, in each valve constructed, the groove of the turn and the fixed orifice of the valve body are located substantially opposite each other. This is a certain drawback which is not compatible with mass production.

 In other types of known valves, it has been thought to remedy this drawback by inclining the groove relative to the axis of the turn. Such an arrangement however led to a total angular travel of the turn, for a determined section of gas passage in the idle position, which varied as a function of the depression of the turn in the valve body. It was then necessary to provide, during manufacture of the valves, an end-of-travel stop adjustment which, here again, was not compatible with mass production.

 In addition, lubricant deposits can form at the end of the groove and then hinder the passage of gas when the turning point is brought to its angular position corresponding to a reduced flow.

 The invention therefore essentially aims to remedy the drawbacks which have just been exposed of currently known valves and to ensure that the gas passage section of the valve body in the turn is approximately independent of the axial depression of the turning in the valve body, whatever the angular position occupied by the turning, in particular for the idling position located beyond the fully open position, and also that the total travel to be covered at the turning to bring it in the idle position is also approximately independent of the depression of the turn in the valve body.

 For these purposes, it is provided, in accordance with the invention, that, at the interface of the turn and the body, two passages are provided for the flow of gas, these two passages being determined by the cooperation of an opening ( first opening) located on one side of the interface with two openings (second openings) located on the other side of the interface and distant from each other along the axis of the turn, these three openings being such (in particular with regard to their shapes, their sections, their relative positions and the mutual spacing of the two second openings) that the sections of the two passages decrease when the turn is turned from a fully open position to an idle position and that the total cross section of the two passages remains, for a given angular position of the turn, approximately independent of the axial entanglement of the turn in the valve body.

 In addition, taking into account the fact that it is ensured that the same passage cross-section is found, whatever the turning of the turn in the valve body, for a given angular position of the turn, the idle position corresponds to a stroke angle of turn which is approximately the same from one tap to another. As a result, the various adjustments necessary in the prior valves have now become irrelevant without however the manufacture of the turn and / or the valve body as well as their assembly being found to be complicated or made more expensive.

 In a first embodiment, the first opening is formed by the orifice of a gas supply duct in the body of the valve and the second openings are constituted by two grooves dug in the external surface of the turn, the orifice of the above duct at least partially overlapping the two grooves.

 In another embodiment, the first opening is constituted by a single groove hollowed out in the external surface of the turn and the second openings are constituted by the orifices of two gas supply conduits in the body of the valve, the groove overlapping at the at least partially the orifices of the two conduits.

 The invention consists, apart from these main provisions, in certain other provisions which are preferably used at the same time and which will be more explicitly discussed below.

 It relates more particularly to certain modes of application (that for which it is applied to taps with conical turning, in particular for gas taps intended for household appliances), as well as certain embodiments of said provisions; and it relates more particularly still, and this as new industrial products, taps of the kind in question comprising application of these same provisions, as well as the special elements specific to their establishment and the assemblies comprising such taps.

The invention may in any case be well understood with the aid of the additional description which follows as well as of the appended drawings, which supplement and drawings are, of course, given mainly by way of illustrative example. In these drawings - Figure 1 shows a schematic perspective, with por
torn off, a gas tap established in accordance with the invention - Figure 2 is a diagram showing the angu positions
respective closing, opening and ra
lenti of such a tap - Figures 9 and 4 show schematically in section
axial a tap in the open position, respec
tively in two cases for which the turn adjustment
conical nant in the valve body is different - Figure 5 schematically illustrates a turning
central gene cited as an example - Figure 6 illustrates in a developed way the appearance of the
bleeding of the turn of Figure 5 - Figure 7 is a front view explaining the function
a valve established in accordance with the invention; - Figure 8 is a sectional view along line AA of
Figure 7 - Figure 9 is a front view explaining the function
nement of another embodiment of a tap with
form of the invention - Figure 10 is a sectional view along line BB
of Figure 9 - Figures 11 and 12 are larger diagrams
scale explaining the operation of a tap
form in the embodiment shown in Figures 1 to
8; and - Figure 13 shows the flow curve of a tap
arranged in accordance with the invention.

 According to the invention, and more particularly according to that of its modes of application, as well as those of the embodiments, of its various parts, to which it seems that there is reason to be given preference, proposing to set up gas taps with conical turn, with one or more grooves on the turn, to ensure the idle flow, this is done as follows or in a similar manner.

 There is shown in Figure 1, in perspective, such a valve, only by way of example and to fix ideas.

 This valve therefore essentially comprises a turn 1 whose working surface is slightly conical, this turn being mounted in a corresponding bore of the body 2, being subjected for example to the action of a spring 3 which connects it to a pusher 4 ( intended to receive a lever), which is guided by a lug 5 moving in a groove 6 of the body 2, any other arrangement that can be provided.

 This is, in the valve shown, to allow communication between, on the one hand, the gas inlet (s) located for example laterally at the valve at 8, and, on the other hand, a gas outlet 7 going to an apparatus for use, and this by means of an interior passage 9 of the turning of the tap, opening passage at 10 on the lateral surface of said turning.

If we denote by 11 the outlets of the channels 8 on the conical bore of the body 2, we see that the conditions for passage at full flow will be achieved when the orifices 10 and It will come face to face.

 In a tap of this kind, generally three characteristic angular positions are provided, namely (FIG. 2) a closed position F, an open position O and an idle position R.

 For the closed position, the inlet orifices It are located in front of the solid wall of the turn 1, so that the gas cannot pass. By printing at the turn a rotation in the direction f (FIG. 2), for example of 9Q0, one arrives at the open position for which the orifices 10 and II are opposite. Finally, by continuing to rotate (arrow f '), a communication is maintained, between 10 and 11, by means of a groove or slot such as 12, formed on the surface of the turn and connected to the orifice 10 (figure 1).

 For an angular position such as that shown in R (FIG. 2) and corresponding to an additional stroke of for example 700 or more, the slow-down effect results from the reduction of the passage section remaining between the edges of the aforesaid groove and the corresponding edges of the fixed orifices 11. In other words, for such a position, the gas arriving through the orifices 8 passes into the groove 12, through the passages of reduced sections or lunules remaining between its edges such as 13 and 16 (FIG. i ) and the corresponding edges 11 it then passes towards the outlet 7 through the orifice 10.

 The section of these lunules (such as S1 and S2 in figure 11) in the intermediate progressive positions going towards the reduced flow depends on the orientation, the relative position of the above edges and the shape of the (or) bleeding.

 In practice, the manufacturing tolerances are such that it is not possible to prevent slight axial offsets, from one tap to another, as visible in FIGS. 3 and 4. We see in FIG. 4 that the turn presents, with respect to the correct assembly of FIG. 3, a certain axial offset e (g being a sinking guard so as not to obstruct the passage of full flow).

 In the embodiment shown in Figures 5 and 6, the turn 1 has, for example, a groove such as 12 generated by a milling cutter, the machining depth of which varies, determining edges 13 and 16 variable according to the flow rates to obtain and inclined by a constant or variable value a relative to the axis of the turn.

 The gas arrives in the body by two passages 8 visible in FIG. 8, leading to the turn at 11. In the full flow position, the orifices 10 and 11 are opposite; by continuing to angularly move the turn to the idle or reduced flow position, communication between 10 and 11 is maintained by means of the groove 12 formed on the surface of the turn and connected to the orifice 10; the gas is then passed through the passages or lunules and S2 (FIG. 7) determined by the opposite portions of the orifices 11 and of the groove 12.

 In FIG. 11 which is a developed and enlarged figure, similar to FIG. 7, it is assumed for example that the turn 1 is, as regards its insertion into the valve body 2, in the ideal position shown in FIG. 3. the respective orifices 10 and 11 are shown, in FIG. 11, in the relative positions going towards the idle, their centers being distant from a distance OR corresponding to the angular stroke effected by the turn.

 The lower edge 13 of the groove 12 and the upper edge 16 of the groove 12 cut the circles of the orifices 11 so as to leave two small reduced passages or lunules S1 and S2 remaining, the section of which decreases when the turn approaches the flow position reduced or idle.

In FIG. 12, it has been assumed that the turn 1 was slightly more sunk into its bore, as shown in FIG. 4, the axial offset being zero. It can be seen that, for an identical angular travel OR of the turn, the offset e, dA to the manufacturing and mounting tolerances in this body-turning assembly, has practically no longer any effect on the sections of passages or lunules previously defined, because it generates for example a decrease in the section of the lunula S1 which becomes but but an increase in the section of the lunula which becomes S2 ', which increase compensates approximately for the decrease in S1, and vice versa
In FIGS. 9 and 10, another embodiment is shown according to which there is only a single orifice 22 for the arrival of the gas, but two grooves 20 and 21 are dug in the surface of the turn 1, in such a way that the inlet orifice 22 opens astride the grooves 20 and 21. Of course, as before, the grooves 20 and 21 are attached to an orifice 23 through which an internal passage at the turn leads to the lateral face of the latter this.

 the passage of the gas is then carried out by two passages or lunules S3 and S4 (FIG. 9) determined by the opposite portions of the orifice 23 and of the grooves S3 and S4.

 the operation of a valve thus arranged remains identical to that indicated above and the same advantages are obtained.

Finally, the device according to the invention has, regardless of the possible offsets e of the turn in the axial direction, the same idle curves, as shown in FIG. 13, in which the flow rates D are plotted on the ordinate and the angular strokes OR of the turn are plotted on the abscissa. In FIG. 13, the flow curve comprises, between the two maximum flows Dm and idle Drt a certain decreasing portion
I substantially linear, corresponding to the decrease in sections S1 and S2 or S3 and S4 as the edges of the grooves move away from the center of the orifices 11 or 22. In the case where the turn is offset axially, we obtain roughly the same curve. it will suffice to provide, as usual, stops to determine the end of the useful angular travel OR, without there being any need to make a fine adjustment of said stops as a function of the axial offset of the turn, as it was the case so far for some of the earlier taps.

 it should be noted that the arrangement in accordance with the invention makes it possible to choose, for the stroke of the reduced flow rate which is generally of the order of 700, any desired value, even beyond 900.

 As regards the means to be provided for making grooves meeting the desired goal, use will be made of any suitably guided milling device, for example using cams or any other system capable of producing the desired shape conforming to the invention.

 The depth as well as the width of the grooves can be constant or on the contrary variable according to any desired law. the two edges of this groove may or may not be parallel.

 Finally, with regard to the choice of the angle, it is within the reach of the technician to best determine the value of this angle, as a function of the mean diameter of the section of the line at the orifice 10 or 23, and the diameter of the orifices 11 and 22, these parameters making it possible to define the value of the lunula S1 and S2 or S3 and S4.

 All that has just been described is supposed to be applied to taps with clonic valves. But it would of course apply to turns of any other shape, in particular cylindrical of revolution.

Thereafter, whatever the embodiment adopted, it is possible to establish taps, in particular gas, whose operation is sufficiently clear from the above so that it is unnecessary to insist on it, and which present, by compared to those of the genre in question already existing, many advantages, in particular - that of making it possible to achieve the progressiveness of the ra
lenti with all the necessary precision, despite the to
manufacturing lerances which can lead to a misalignment
more or less large of the turn, - and that of allowing to choose, for the race
idle angle, any suitable value, even better
less than the generally adopted value of 700, so
independent of the turning of the turning point in the body.

 As goes without saying and as it already follows from the above, the invention is in no way limited to those of its modes of application and embodiments which have been more especially envisaged; it embraces, on the contrary, all variants, in particular that for which the groove or groove would be provided, no longer on the turn, but on the corresponding surface of the valve body.

Claims (9)

HEVEWUICAFIONS  1 - Rotary tap, in particular gas, comprising a rotary displaceable in rotation in a tap body, characterized in that, at the interface of the turn and the body, two passages are provided for the flow of gas, these two passages being determined by the cooperation of an opening (first opening) located on one side of the interface with two openings (second openings) located on the other side of the interface and distant from each other along the axis of the turn, these three openings being such (in particular as regards their shapes, their sections, their relative positions and the mutual spacing of the two second openings) that the sections of the two passages decrease when the turn is turned from a fully open position to an idle position and the total section of the two passages remains, for a given angular position of the turn, approximately independent of the axial insertion of the turn into the valve body and.  2 - Faucet according to claim 1, characterized in that the first opening is constituted by the orifice of a gas supply conduit in the body of the valve and in that the second openings are constituted by two grooves dug in the external surface of the turn, the aforementioned orifice leads at least partially overlapping the two grooves.  3 - Faucet according to claim 1, characterized in that the first opening is constituted by a single groove dug in the external surface of the turn and in that the second openings are constituted by the orifices of two gas supply conduits in the valve body, the groove at least partially overlapping the orifices of the two conduits.  4 - Tap according to claim 2 or 3, characterized in that the longitudinal axis of symmetry of each groove is substantially perpendicular to the axis of the turn.  5 - Tap according to claim 3, characterized in that the axes of symmetry of the grooves are inclined relative to the axis of the turn and diverge from each other from the fully open position to the idle position .  6 - Tap according to any one of claims 2 to 5, characterized in that the lateral edges of each groove converge towards each other, the smallest width corresponding to the idle position.  7 - Tap according to claims 2 and 4, characterized in that the lateral edges of each groove are parallel to each other.  8 - Tap according to claim 6 or 7, characterized in that each groove has a constant depth.  9 - Tap according to claim 6 or 7, characterized in that each groove has a minimum variable depth at the end of the groove corresponding to the idle position.