MIXING VALVE OF SINGLE LEVER TYPE PROVIDED WITH A DEVICE FOR PREVENTING PRESSURE SHOCK DURING CLOSING MOVEMENT OF THE LEVER

Abstract: A device for mixing valves of the one lever type for liquids, for example hot and cold water, of the kind that comprises a valve housing (10) provided with inlets (19) and a common outlet (20) for the liquids, an operating member (12) for controlling the amount and the temperature of the liquid flowing through the outlet, where the operating member is connected to an actuator (14) in the valve housing (10) cooperating with a valve member (17). The actuator (14) has a built-in soft closing function intended to prevent too quick shut-off of the valve, where the soft closing function includes at least one sealed chamber (23) that comprises a movable piston (21) which, during the closing movement of the operating member (12), forces a fluid out from the chamber (23) via a throttling member (28). When the fluid pressure exceeds a certain value in said chamber (23), the throttling member (28) is forced progressively against a sealing face (33) in the actuator (14) and is deformed elastically, whereby the flow passages (43) provided in the throttling member are reduced so that the flow resistance increases for a fast closing movement, and the flow resistance is low for a slow closing movement.

Description: MIXING VALVE OF SINGLE LEVER TYPE PROVIDED WITH A DEVICE FOR PREVENTING PRESSURE SHOCK AT CLOSING MOVEMENT OF THE LEVER. Technical field The present invention refers to a device at mixing valves of one lever type for fluids, for example hot and cold water, and of the type that comprises a valve housing, which is provided with each an inlet and a common outlet for the liquids, an operating member for regulating the amount and the temperature of the fluid flowing out through the out¬ let, where the operating member is connected with a valve member cooperative actuator provided in the valve housing, whereby the actuator shows a built-in soft closing function intended to prevent too quick shut off of the valve, where the soft closing function includes at least one sealed chamber that comprises a movable piston which at the closing movement of the operating member is provided to press a fluid out from the chamber via a throttling member. The backgound of the invention At a quick shut off of certain mixing valves of one lever type, in particular if the water pipes are of small dimen¬ sion, it can arise a pressure chock that exposes the water work system for strong loads as well as causes noise. Through for example SE-B-462 503 and SE-B-455 124 it is earlier known mixing valves, which are provided to build up a pressure in a provided part of the valve at a quick shut off of the valve lever, so that a certain damping resistance is obtained at the endphase of the lever, which requires added force and thereby extends the closing phase. This happens by the reason that the valve is equipped with a separate pressure chamber, that is filled up via a non-r¬ eturn valve when the valve opens. When closing the valve the water is pressed out from the pressure chamber through passages in the non-return valve, whereby too quick closing movements are slowed down. These known so called soft closing mixing valves show the disadvantage that they feel inert even at a normal shut off compared to a mixer without the soft closing function. They are furthermore sensitive to impurities in the water, which may damage the parts included in the soft closing function. Moreover the whole valve begins to leak if a leakage arise in the soft closing function. The object of the invention and its most important characteristic The object of the present invention is to achieve a mixing valve with a built-in soft closing function of the type mentioned in the introduction, which does not or in very little degree affects the closing movement at a normal shut off of the valve and influences only at a quick closing movement. This has according to the invention been achieved by the fact that the throttling member, when the pressure from the fluid is exceeding a certain value in said chamber, is provided to be pressed progressivly against a sealing face in the actuator and is hereby deformed elastically, whereby the flow passages arranged in the throttling member are reduced, so that the flow resistance increases at a quick closing movement, while the flow resistance at a slow closing movement is low. Specification of the drawings The invention will be described in the following with refe¬ rence to the enclosed drawings which shows an embodiment. Fig. 1 is a vertical section through a mixing valve, for example a mixing valve for wash basins, equipped with the device according to the invention. Fig. 2 shows the closed position of the valve on an enlarged scale a section through the actuator placed in the valve housing. Fig. 3 is a section corresponding fig. 2 but in the open position of the valve. Fig. 4 shows on an enlarged scale a section through the throttling member arranged in the device, in the unaffected normal position. Fig. 5 discloses a cut analogous with fig. 4 through the throttling member in affected, throttled position. Fig. 6 discloses the throttling member in a view from the above. Description of the embodiment The mixing valve shown in fig. 1 is of so called one lever type and includes a valve housing 10 with a spout 11 and a control lever 12. The upper part 13 of the valve housing 10 is by means of the control lever 12 rotateable about a vertical axis, which permits regulation of the temperature of the outflowing water. The upper part 13 of the valve housing co-operates further with an actuator 14 pivoted about a horisontal axis 15. The lever 12 can be regarded as a double-armed lever, which is pivoted about a vertical axis as well as about a horison¬ tal axis and whose shorter lever arm 16 constitutes a part of the actuator 14 and actuates a movable valve plate 17. This bears against another firm valve plate 18, which is provided with two inlet passages 19, of which only one of those is visible in the drawing, one for cold water and one for hot water respectively as well as an outlet passage 20, which communicates with the spout 11. In the actuator 14 is provided a soft closing function including two pistons 21 and 22, - fig. 2 and 3 - which are slidably fitted in each a chamber 23 and 24 and sealed against these with 0-rings 25 and 26 or another type of sealing. The chambers communicate with each other via a passage 27 in the actuator 14, where the passage is filled by a fluid, for example oil. Between the first chamber 23 and the passage 27 is provided a throttling member 28, which is described more in detail below. The two pistons 21 and 22 co-operate each with a stop face 29 and 30 in the valve housing 10. When the valve is open (fig. 3), the first piston 21 is pushed out a distance from its chamber 23, while the other piston 22 is pushed into its chamber 24. When shutting off the valve, i.e. a swing move¬ ment downwords of the lever 12, the first piston 21 will co¬ operate with the stop face 29 and be pressed into its cham¬ ber 23 and the fluid will be pressed out to the passage 27 and into the other chamber 24 and press out the other piston 22 via the throttling member 28 to the position shown in fig. 2. When the valve opens, the fluid will flow in the opposite direction into the first chamber 23 via the thrott¬ ling member 28. This soft closing device is in contrary to earlier known inventions insensitive to impurities in the water, when it is not operating with the tap-water as pressure medium. Besides, the remaining function of the valve is not affected by a possible leakage in the soft closing function. At a possible functional disturbance it is only needed to change the actuator 14. By earlier known devices it is necessary to change the whole control device, which is considerably more expensive as well as more complicated and requires a shut off of the tap-water. An example of a throttling member 28 is shown in detail in fig. 4, 5 and 6 and includes a disc 31 equipped with a guide pin 32, which guides up the disc in the chamber 23. The disc 31 interacts with a sealing face 33 in the actuator 14 and shows on the side facing the sealing face 33 an inner, ring- shaped flange 34 provided with a radial opening 35 and an external ring-shaped flange 40. This one is axially a little higher than the inner flange 34, so in interaction with the sealing face 33 a first ring shaped space 41 and another inner space 42 inside the flange 34 are formed. The space 41 communicates with the chamber 23 via a hole 36 and the space 42 is in connection with the passage 27. Between the end surface of the inner flange 34 and the sealing face 33 is a gap 43 formed when the throttling member is in its unac- tivated position. The throttling member 28 is in the shown example spring loaded, but the positioning can even be done with another method. In fig. 4 the throttling member 28, is shown in unactivated position, i.e. when a fluid with low pressure can pass by the throttling member via the hole 36, the space 41, the passage 35 and the space 42, either at the opening movement of the valve from the chamber 23 to the passage 27 or in the contrary direction at a normal, slow closing movement. At a quick closing movement however, the pressure onto the disc 31 from the fluid in the chamber 23 will increase quick, - fig. 5 - whereby the flange 34 will be tightened against the sealing face 33 and an elastic deformation of the disc 31 occurs, so that the gap 43 between the sealing face 33 and the flange 34 is adjusted by means of the pressure in the chamber 23. Hereby the flow resistance increases in the throttling member 28 and the closing movement slows down. The throttling member 28 works progressively by this method, i.e. the faster closing movement, the bigger flow resistance and damping. Such a progressive throttling member can naturally be desig- ned in many different ways. The principle is however that it is elastically deformable when the pressure increases fast, caused by a quick closing movement, so that the size of the flow passages in the throttling member reduces and the closing movement slows down. The throttling member 28 can eventually be designed without the opening 35, whereby the lever movement completely stops at a quick shut off. In the actuator 14 is further provided a stop member by means of a screw 37 fixed in a cylinder 39 which is loaded by a spring 38, that when the mixing valve opens will bear against a firm stop face which can be the same as the stop face 29. The purpose of the stop member is to limit the torsion of the actuators 14 about the axis 15 and thereby a limitation of the maximal outflow of liquid through the outlet 20. The position of the.screw 37 in the cylinder 39 is adjustable for setting of increased maximal outflow. Since the cylinder 39 with the screw 37 is mounted with a spring in the actuator 14, one can by placing the screw 37 against the stop face 29 and by pressing up the lever 12 further, temporarily increase the flow passing the stop position. The invention is of course not limited to the embodiment shown but can be modified within the scope of the claims. Therefore the fluid can be a liquid or a gas and instead of the double piston arrangement shown, a simple single acting piston corresponding to the piston 21 can be used, for example a device affected only at the shut off of the mixing valve. The other pistons function can for example.be taken over by an expandable accumulator. In this case the fluid can be air, or another gas.

Claims: CLAIMS 1. A device at mixing valves of one lever type for fluids, for example hot and cold water, and of the type that compri¬ ses a valve housing (10), which is provided with each an inlet (19) and a common outlet (20) for the fluids, an operating member (12) for controlling the amount and the temperature of the liquid flowing out through the outlet, where the operating member is connected with an actuator (14) cooperating with a valve member (17) arranged in the valve housing (10), whereby the actuator (14) shows a buil¬ t-in soft closing function intended to prevent too quick shut off of the valve, which soft closing function includes at least one sealed chamber (23) that comprises a movable piston (21) which at the closing movement of the operating member (12) is arranged to press a fluid out from the cham¬ ber (23) via a throttling member (28), c h a r a c t e r i z e d t h e r i n, that the throttling member (28) is provided to, when the pressure from the fluid in said chamber (23) exceeds a certain value, be pressed progressively against the sealing face (33) in the actuator (14) and hereby be deformed elas¬ tically, whereby the flowing-through passages (43) provided in the throttling member are reduced, so that the flow resistance increases at a quick closing movement, while the flow resistance is low at a slow closing movement. 2. A device according to claim 1, c h a r a c t e r i z e d t h e r e i n, that the throttling member (28) consists of a disc (31), which by its side facing the sealing face (33) is provided with ring-shaped flanges (34,40) or the like of different height, which flanges together with the sealing face (33) form two spaces (41,42), that communicate with each other via at least one variable opening (43). 3. A device according to claim 1 or 2, c h a r a c t e r i z e d t h e r e i n, that the said soft closing function includes two pistons (21,22) which are slidable fitted in each its chamber (23,24), which chambers communicate with each other via a passage (27) arranged in the actuator, which passage is filled with the said fluid, that the first piston (21) at the closing movement of the operating member (12) is arrang¬ ed to be brought to bear against a first stop face (29) in the valve housing (10) and hereby be pressed into its first chamber (23) by effect of said fluid , whereby at the same time the other piston (22) is pressed out from its other chamber (24) in corresponding degree. 4. A device according to claim 3, c h a r c t e r i z e d t h e r e i , that the other piston (22) at the opening movement of the operating member (12) is arranged to be brought, to bear against the other stop face (30) in the valve housing (10) so that it by effect of said fluid is pressed into its other chamber (24) whereby at the same time the first piston (21) is pressed out from its first chamber in corresponding degree, whereby said throttling member (28) is arranged between the first chamber (23) and the passage (27). 5. A device according to claim 1, c h a r a c t e r i z e d t h e r e i , that the said actuator (14) consists of a stop part (37) cooperating with a stop face for limiting the maximal out¬ flow of liquid, where the stop part consists of a spring loaded (38) screw (37) which is provided to spring and give a temporary increase of the flow when tightened against the stop face. 6. A device according to claim 5, c h a r a c t e r i z e d t h e r e i n , that the position of the screw (37) is adjustable to set said maximal outflow.

Inventors: RIIS VOLDEMAR, RIIS, VOLDEMAR
Applicants: GUSTAVSBERG VAARGAARDA ARMATUR, GUSTAVSBERG VAARGAARDA ARMATUR AB
Application year: 1992
Main classification: F16K47
IPC codes: F16K47