MXPA96004933A - Shuttle valve with - Google Patents

Abstract

The present invention relates to a conical sealing valve comprising a body having a passage through it for the flow of the medium, two chambers and a conical perforation intercepting said passage, a conical shutter (11; 24; 50; 70) having an outer surface (16), a broad end (20) and a narrow end (15) located rotatably in the bore and adapted to block said passage in a closed condition of the valve, one of the chambers being found at the wide end (20) of the obturator and the other at the narrow end (15) and a shaft (84; 71) separated but manageably connected to the obturator (11; 24; 50; 70) to cause rotation thereof, having the shutter (11; 24; 50; 70) a port (12) adapted to be in communication with said passage in an open condition of the valve, and a channel (17) which is not connected to the port (12) but the which connects the wide end (20) with the narrow end (15) for p the pressure equalization in the two chambers at both ends (20 and 15), characterized in that a non-return valve (21; 25; 51; 75) is placed in the channel (17) to allow the pressure change and the associated flow from the broad end to the extreme end

Description

CONICAL SHUTTER VALVE BACKGROUND OF THE INVENTION This invention relates to a conical obturator valve 5. The shutter of a so-called "pressure balanced" taper valve is provided < - "Or conventionally with two holes, one that connects the port in the shutter with the wide end of the shutter and the other that connects the port with the narrow end.

This equates the pressure at the ends of the obturator for the linear pressure of the linear medium flowing through the valve. Often a non-return valve is provided in the hole adjacent to the narrow end, allowing the linear medium flow from the ports to the end. narrow. Such a valve is disclosed in FR-A-2328905. However, it has been found that in some cases the linear medium causes corrosion of the plug and / or deterioration of the lubricant / sealant. In addition, if the linear medium 20 is dirty or abrasive, the holes can be blocked and / or the non-return valve becomes damaged, clogs, or otherwise causes its malfunction. US-A-2124359 and US-A-2573238 disclose each conical sealing valve having a body, a conical obturator in a conical perforation in the body, a, that separates from, but that connects manageably to, the body and a duct in the obturator that connects the broad and narrow ends thereof. However, sometimes there is a momentary increase in pressure at the wide end that forces the obturator into the hole and causes it to jam. SUMMARY OF THE INVENTION It is an object of the present invention to provide a conical sealing valve that does not suffer, or suffer to a lesser extent, from these disadvantages. According to the invention, a conical sealing valve comprises a body having a passage through it for the flow of the medium, two chambers and a conical perforation intercepting said passage, a conical shutter having an external surface, a broad end and a narrow end located rotatably in the bore and adapted to block said passage in a closed condition of the valve, one of the chambers being at the wide end of the obturator and the other at the narrow end, and a separate but handily connected shaft to the shutter to cause rotation thereof, the shutter having a port adapted to be in communication with said passage in an open condition of the valve and a channel which is not connected to the port but which connects the wide end to the narrow end to allow the equalization of the pressure in the two chambers at the two ends of the obturator, characterized in that a valve without The return is placed in the channel to allow the pressure change and the associated flow from the wide end to the narrow end. The non-return valve thus retains the sealant / lubricant in the chamber at the narrow end. This non-return valve is placed more normally adjacent the narrow end to minimize the volume of sealant / lubricant in the channel and the chamber at the narrow end but can be placed adjacent the broad end. The pressure change is such that the pressure in the chamber at the wide end is reduced and the pressure in the chamber at the narrow end increases until equalization occurs. However, the pressure at the narrow end can be made greater than at the wide end thereby creating an acceptable imbalance force, which helps prevent the plug from becoming stuck in the bore. The channel that connects the wide end with the narrow end can be formed by direct drilling through the obturator, avoiding the connection with the port. Alternatively, the channel can be formed by melting a longitudinal groove in the outer surface of the plug and then securing it for example by welding a cylindrical tube in position in the groove. In addition, alternatively, the channel may comprise a groove formed in the external surface of the sealant and which also carries sealant / lubricant to provide a film between the external sharpened surface i.e., conical of the shutter and the surface it sees towards the inside of the slot. BRIEF DESCRIPTION OF THE DRAWINGS Five embodiments of the invention will now be described by way of example with reference only to the accompanying drawings, of which: Figure 1 shows a side view, partially in section of a shutter of a known conical sealing valve; Figure 2 shows a side view, t, partially in section, of a shutter of a conical sealing valve according to a first embodiment of the invention; Figure 3 shows a view from above of the obturator shown in figure 2. Figure 4 shows a side view, partially in section, of a shutter of a conical sealing valve according to a second embodiment of the invention; Figure 5 shows a side view, partially in section, of a shutter of a conical sealing valve according to a modification of the second embodiment of the invention. Figure 6 shows a side view, partially in section, of a shutter of a conical sealing valve according to a third embodiment of the invention; Figure 7 shows a view from the top of the obturator shown in Figure 6. Figure 8 shows an elongation of part of the view shown in Figure 6; Figure 9 shows a side view, partially in section, of a shutter of a conical sealing valve according to a fourth embodiment of the invention; Figure 10 shows a view from the top of the shutter shown in Figure 9; Figure 11 shows an elongation of part of the view shown in Figure 10. Figure 12 shows a side view, partially in section, of a shutter of a conical sealing valve according to a fifth embodiment of the invention; and Figure 13 shows an elongation of part of the view shown in Figure 12.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES As shown in Figure 1, the known sealing valve comprises a conical obturator 1 which fits into the correspondingly configured perforation of a valve body (not shown). The tapered plug has a port 2 through which the linear means can flow, and two longitudinal grooves 3, 4 formed on the outer surface 6 of the plug to carry sealant / lubricant to the inner surface of the bore against which the plug is seated. shutter. However, the slots do not extend to each end of the plug. A driver shaft (not shown) is provided at the narrow end 5 at the top of the plug. In use, this shaft causes the obturator to rotate about the 0-0 axis between open and closed positions. The obturator is provided with two holes 7, 8, a hole 7 leading from the narrow end 5 at the top of the obturator to port 2 and the other hole 8 leading from the broad end 9 at the bottom of the obturator to the port 2. In the upper hole 7 a non-return valve 10 is provided to prevent flow from the space in the upper part of the shutter towards the port. The two holes 7, 8 allow the pressure in the spaces in the valve body above and below the plug to be equal to the pressure of the linear medium and prevents the plug from moving axially away from its seat on the bore. if the linear pressure changes suddenly. However, the non-return valve 10 can be damaged, clogged, or otherwise cause its malfunction if the linear means is corrosive or carries dirt, for example small sand particles. The first embodiment of the invention, shown in FIGS. 2 and 3, comprises a conical sealing valve having a conical seal 11 which fits into the correspondingly configured opening of a valve body (not shown). The tapered plug 11 has a port 12, two longitudinal grooves 13 and a circumferential groove 14 formed on the tapered external surface 26 of the plug to carry sealant / lubricant to the inner surface of the bore against which the plug seats. The circumferential groove 14 is positioned close, but spaced from the wide end 20 of the obturator, and the two longitudinal grooves, 13, one diametrically opposite to the other (see Figure 3) extend from the circumferential groove to the narrow end 15 of the obturator. A drive shaft (not shown) has a configured end which fits in a rectangular transverse recess 18 at the narrow end 15 on the top of the plug and in use, rotates the plug 11 about the axis P-P between the open and closed positions. The plug is provided with a channel 17 formed by fusing a wide groove 89 having parallel sides and a semi-cylindrical base on the outer surface 16, the groove extending all the way from the narrow end 15 to the broad end 20 of the plug. A circular transverse tube 19 is placed at the base of the wide slot 89, matching the outer diameter of the tube with the internal diameter of the base of the slot, and welded in position, filling the welding alloy 22 with the remainder of the wide slot 89. The axis of the tube is generally parallel to the external conical surface 16. Channel 17 is placed between port 12 and outer surface 16 so as not to communicate with any. Adjacent to the small end 15 in the upper part of the obturator, the tube 19 is provided with a non-return valve 21, thus allowing the pressure change and the associated flow from the broad end 20 in the lower part towards the narrow end 15 in the top but not in the reverse direction, with the result that pressure equalization occurs in the chambers at the upper and lower ends. However, due to the presence of the valve 21, the pressure in the chamber at the top, that is, the narrow end of the obturator, may be momentarily greater than the pressure in the lower chamber, ie at the wide end of the lower part of the obturator, but this pressure will be lightened due to the resulting movement of the obturator. The channel 17 through the tube 19 allows the pressure at the upper end of the plug to be automatically matched to that at the wide end 20. However, since there is no communication between the non-return valve and port 12, it does not it can be damaged, clogged or otherwise cause its malfunction through the linear medium or dirt carried by it. The second embodiment of the invention, shown in Figure 4, comprises a conical sealing valve having a shutter 24 with many features that are equal to that of the shutter of the first embodiment. The same numbers have been given to the characteristics that are the same in Figure 4 as in Figure 2, and will not be described again. The obturator of this embodiment has a channel 17 formed by drilling a hole all the way through the obturator from the narrow end at the top to the wide end at the bottom, the axis of the hole being parallel to the rotational axis QQ of the shutter . The hole lies between the port and the external conical surface of the shutter and does not communicate with any.

Adjacent to the narrow end of the hole is a non-return valve 25, seated in an enlarged portion 26 of the hole. In use, the flow can occur from the wide end 20 of the obturator to the narrow end 15 5 to equalize the pressure. In Figure 5 a modification of the second mode is shown. A drive shaft 84 is connected to the "Shutter" at its wide end by a shaped tab 82 that fits into a rectangular recess 18. io The shutter (and perforation) is reversed with respect to the construction shown in Figure 4, the wide end being now at the top and the narrow end at the bottom. In all other aspects the obturator (and the perforation) is the same. The third embodiment of the invention shown in j ^. Figures 6, 7 and 8, comprises a shut-off valve having a stopper 50 which engages in the correspondingly configured bore of a valve body (not shown). As the shutter of the first In an embodiment, the shutter 50 has a port 12, two longitudinal grooves 13 and a circumferential groove 14. A non-return valve 51 is located in a threaded screw bore 52 located at the wide end of the obturator. The base of the perforation is formed with a hole 53 extending parallel to the rotational axis PP of the obturator and this hole is connected by an additional hole 54 extending radially from the axis PP to one of the longitudinal grooves 13. In this way, a connection is made from the wide end to the narrow end of the obturator through the threaded screw bore 52, the bore 53, the additional hole 54 and the groove 13, and allows the pressure equalization to occur between the two ends. Alternatively, the position and configuration of the bore, the hole and the additional bore may be such that the connection is made with the circumferential groove 14, thus allowing pressure equalization to occur from the wide end to the narrow end of the shutter. through both longitudinal grooves 13 and the circumferential groove 14. The obturator 60 of the valve of the fourth embodiment of the invention shown in figures 9, 10 and 11 has all the characteristics of the valve of the fourth embodiment. However, as can be seen particularly in Figures 9 and 11, an additional non-return valve 65 is located in a threaded screw bore 66 at the wide end of the obturator and a passage 67, preferably having a filter 68 therein, that connects the pier to the port. In this way, the equalization of pressure between the port and the wide end is allowed to occur. The valve of the fifth embodiment of the invention has a shutter 70 (shown in FIGS. 12 and 13) which has an axis 71 connected thereto by means of a shaped tongue 88 which fits into a rectangular recess 86 at the wide end . A circumferential groove carrying sealant / lubricant 72 is provided at a small distance from the wide end 73 and two longitudinal grooves carrying sealant / lubricant 74 (only one is shown), diametrically positioned with respect to each other and to the rotational axis QQ of the obturator, which connect the circumferential groove with the narrow end 77 of the obturator 70. A non-return valve 75 is located in a bore 76 at the wide end and a passage 78 connects the base of the bore with the circumferential groove 72 as shown particularly in figure 13, (or with one of the two longitudinal grooves). In this way, a channel is provided which connects the wide end at the top of the obturator with the narrow end at the bottom, through the perforation 76, the passage 78, the circumferential groove 72 and the two longitudinal grooves, thus enabling pressure equalization occurs.

Claims (5)

1. NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and therefore the property described in the following claims is claimed as property. A conical sealing valve comprising a body having a passage through it for the flow of the medium, two chambers and a conical perforation intercepting said passage, a conical obturator (11; 24; 50; 70) having an outer surface (16), a broad end (20) and a narrow end (15) located rotatably in the bore and adapted to block said passage in a closed condition of the valve, with one of the chambers being at the wide end (20) of the obturator and the other at the narrow end (15) and a shaft (84; 71) separated but manageably connected to the obturator (11; 24; 50; 70) to cause rotation thereof, having the obturator (11); 24; 50; 70) a port (12) adapted to be in communication with said passage in an open condition of the valve, and a channel (17) which is not connected to the port (12) but which connects the wide end (20) to the narrow end ( 15) to allow equalization of pressure in the two chambers at both ends (20 and 15), characterized in that a non-return valve (21; 25; 51; 75) is placed in the channel (17) to allow the change of pressure and the associated flow from the broad end to the narrow end.
2. 2. A conical sealing valve according to claim 1, characterized in that the non-return valve (21; 25) is positioned adjacent to the narrow end.
3. 3. A conical sealing valve according to any of the preceding claims, characterized in that the channel (17) is formed by drilling directly through the obturator (24), avoiding the connection with the port (12). A conical sealing valve according to any of claims 1 to 3, characterized in that the channel (17) comprises a groove (13) formed on the external surface (16) of the plug (50; 70). A conical sealing valve according to any of claims 1 to 3, characterized in that the channel (17) is formed by casting a longitudinal groove (89) on the external surface (16) of the plug (11) and the subsequent securing of a tube (19) in position in the groove (89).