Ball check valve

Abstract: A ball valve comprising: a first body portion (16 1 ) having an inlet (32 1 ), an outlet (34 1 ) and an aperture (26 1 ); a second body portion (50 1 ) closing off the aperture (26 1 ) of the first body portion (16 1 ), the first and second body portions (16 1 ,50 1 ) together defining a chamber; a valve seat (46 1 ) in the first body portion (16 1 ) dividing the chamber into inlet and outlet regions (62 1 ,64 1 ); a ball guide (56 1 ) forming part of the second body portion disposed in the outlet region (64 1 ); a ball (70 1 ) movable between a first position in which it sits on the valve seat (46 1 ) and blocks fluid flow between the outlet and inlet, and a second position in which the ball abuts against the ball guide (56 1 ) and fluid can flow between the inlet and outlet, the second body portion being detachable from the first body portion, the aperture (26 1 ) being sized such that, on removal of the second body portion, access is provided to the valve seat.

Description: The present invention relates to a ball valve. The ball valve of the present invention has particular, but not exclusive, application to the field of sewage handling. Problems arise when conventional ball valves are used in sewage handling, for example, on the inlet and outlet of a sewage pump, due to the presence of objects in sewage which lodge themselves within the valve and prevent it from operating correctly. The efficiency of the associated pump is often impaired. Typical objects include toothbrushes, disposable razors and rags. Throughout the specification, the term "fluid" is to be understood not only in its conventional sense but also as including both the liquid medium and the suspended solid material components of sewage. Patent application number DE-A-1750711 discloses a check valve having a closing body that moves between a seat and a stop to allow fluid to flow through the valve to a valve outlet. US patent number 1,721,353 discloses a check valve comprising a casing having a seat, a ball valve and means for suspending the ball so that it may swing freely laterally toward and away from the seat, the means including a rod on which the ball is slidably mounted. The present invention provides a ball valve in accordance with claim 1 of the appended claims. A ball valve according to the invention comprises: a first body portion having an inlet, an outlet and an aperture; a second body portion closing off the aperture of the first body portion, said second body portion being detachable from the first body portion, the first and second body portions together defining a chamber; a valve seat in the first body portion dividing the chamber into inlet and outlet regions; a ball guide disposed in the outlet region; a ball movable between a first position in which it sits on the valve seat and blocks fluid flow between the outlet and the inlet, and a second position in which the ball abuts against the ball guide and fluid can flow between the inlet and the outlet, characterised in that: the ball guide forms an integral part of the second body portion; and in that due to the size of the aperture and the integral configuration of the ball guide and the second body portion, on removal of the second body portion, immediate access is provided to the valve seat. Preferably, the aperture is sized to permit the removal and replacement of the valve seat. By the provision of the above features, the present invention provides a ball valve which is readily maintainable in that access is afforded to the interior of the ball valve via the aperture in the first body portion without the need to disconnect its inlet and outlet from the other elements of the sewage handling circuit. In this way, any blockages lodged in the valve such as toothbrushes and disposable razors can be readily removed and/or the valve seat can be easily replaced, after simply detaching the second body portion from the first body portion. An exemplary embodiment of the invention is hereinafter described with reference to the accompanying drawings, in which: Figure 1 shows an exploded, cross-sectional view of a ball valve in accordance with the present invention; Figure 2(a) shows the ball valve of Figure 1 from a similar view, but in unexploded form; Figure 2(b) shows the ball valve of Figure 2(a) when viewed from above; Figure 3 shows a first body portion of the ball valve of Figure 1 in isolation; Figures 4(a), 4(b) show sections A,A and sections B,B of Figure 3; Figure 5(a) shows an annular stainless steel plate for securing a valve seating in situ; Figure 5(b) shows a valve seating; Figure 6(a) shows a cross-section of a second body portion of the ball valve in Figure 1 in isolation; Figure 6(b) shows a view from below Figure 6(a); Figure 7(a) shows the second body portion when the valve is in use and viewed from the outlet; and Figure 7(b) shows a view of Figure 7(a) in plan. The reference numerals used in describing the above drawings are followed by 1 in order to distinguish them from the other numerals in the drawings which represent dimensions in mm's. Referring to Figure 1, the illustrated ball valve of the present invention, which is designated generally by 10 1 , is suitable for use in sewage handling, for example, on the inlet and outlet of a ram or diaphragm pump. It comprises a housing 12 1 made up of two cooperating castings a first body portion or main body portion 16 1 and a second body portion or dome 50 1 . Figure 2(a) shows the two castings attached to each other. Referring to Figures 3, 4(a) and 4(b), the main body portion 16 1 comprises a generally tubular portion 17 1 having a central longitudinal axis X,X and which provides at opposite ends thereof an inlet 32 1 and an outlet 34 1 . As is best shown in Figures 4(a) and 4(b), the tubular portion comprises a floor 20 1 , from which two diverging walls 22 1 upstand, and a ceiling portion 24 1 . The ceiling portion 24 1 , midway therealong, includes an aperture 26 1 which provides communication with or access to the interior of the main body portion 16 1. Surrounding the aperture 26 1 , there is also provided an annular flange 27 1 which provides the means by which the main body portion 16 1 is attached to the dome 50 1 . The main body portion 16 1 also includes annular flanges 18 1 which surround the inlet 32 1 and outlet 34 1 and provide the means by which the ball valve is connected to other elements of the sewage handling system. Inside the main body portion 16 1 , there is also provided a planar wall 36 1 which extends at an angle to the central longitudinal axis X,X of the main body portion 16 1 and connects the ceiling portion 24 1 to the floor 20 1 . From Figure 1, the angle in the described embodiment can be seen to be 35°. The wall 36 1 includes a circular orifice 38 1 . The dotted line labelled S in Figure 3 shows the intended position of the valve seat assembly. In order to fit valve seat assembly, a circular recess 44 1 is formed in the wall surrounding the circular orifice 38 1 by removing the metal 42 1 thereby revealing surface 44 1 which is then provided with threaded holes. Clearly, the aperture 26 1 must be of sufficient size to permit the metal 42 1 to be readily machined. A plastic or rubber annular valve seat or seating 46 1 as shown in Figure 5(a) is placed in the recess 40 1 against the surface 44 1 and is affixed thereto using a stainless steel, annular plate 47 1 as shown in Figure 5(b). The plate 47 1 is secured to the surface 44 1 using screws which cooperate with the threaded holes in the surface 44 1 , thereby sandwiching the seating 46 1 in position. Referring to Figure 6(a) and 6(b), the second body portion or dome 50 1 comprises a dome portion 51 1 having an annular flange 52 1 surrounding its open end. The flange 52 1 provides the means by which the dome 50 1 is secured to the main body portion 16 1 . The dome 50 1 also comprises a ball guide 56 1 integrally formed therewith which includes a pair of spaced abutments 58 1 . The dimensions of the ball guide 56 1 are selected such that when the dome is attached to the main body portion 16 1 , i.e. by sitting the dome on the ceiling portion 24 1 such that it closes off the aperture 26 1 and bolting the flanges 27 1 and 52 1 together, the end of the ball guide 56 1 marries with the main body portion 16 1 in close relation, such that the gap between the wall 36 1 and the end of the ball guide 56 1 is typically in the order of 1mm. In this assembled condition and referring to Figure 2(a), the ball valve can be thought of as defining a chamber comprising an inlet region 62 1 on the side of the valve seat 46 1 adjacent the inlet 32 1 and an outlet region 64 1 on the side of the valve seat 46 1 adjacent the outlet 34 1 , including the volume enclosed by the dome portion 51 1 . In operation, a ball 70 1 sits in the region enclosed by the ball guide 56 1 , the valve seat 46 1 and the dome 50 1 . This region is hereinafter referred to as the ball-confinement region and is designated 72 1 . It will be noted that the ball 70 1 can be removed from the ball-confinement region 72 1 via the aperture 26 1 . In use, in-line in a sewage handling system, for example, on the inlet of a ram or diaphragm pump, the ball valve 10 1 has two modes of operation. In a first mode, when the pressure at the outlet 34 1 is greater than at the inlet 32 1 , i.e. during the downstroke of the associated pump, the ball occupies a first position in the ball-confinement region 72 1 in which it sits on and seals against the valve seat 46 1 , and thereby blocks fluid flow between the outlet and inlet. Figure 7(a) shows the ball in this position. In a second mode, when the pressure at the outlet 34 1 is less than at the inlet 32 1 , i.e. during the upstroke of the associated pump, the ball occupies a second position in which it rolls or spins up the ball guide 56 1 into the volume enclosed by the dome portion 52 1 and permits fluid to flow between the inlet 32 1 and outlet 34 1 . As the pump starts its downstroke again, the ball 70 1 tends to return to the valve seat by rolling or spinning down the ball guide 56 1 . The tendency for the ball 70 1 to return to the valve seat 46 1 via the ball guide 56 1 reduces the likelihood of the ball bouncing on the wall 36 1 , the annular plate 47 1 or the valve seat 46 1 and so reduces the wear on the ball 70 1 . The tendency for the ball to roll or spin ensures that the ball wears evenly and also assists the ball's return-passage from the volume enclosed by the dome portion 52 1 through the fluid being pumped to the valve seat 46 1 . It will be noted that the region adjacent the bottom end of the dome 50 1 is slightly oval i.e. 145 mm from front to back, see Figure 1 and 136 mm across, see Figure 7(a). This shaping also assists in imparting spin onto the ball and in returning the ball through the fluid to the valve seat 46 1 , when the ball does not return to the valve seat 46 1 via the ball guide 56 1 . As will be appreciated from the foregoing, if the ball valve 10 1 becomes blocked or requires a replacement valve seat 46 1 , it is simply necessary to remove the dome 50 1 , perform the unblocking or replacement operation via the access afforded by the aperture 26 1 , and replace the dome 50 1 . All this can be achieved without the need to disconnect the inlet and outlet of the ball valve from the other elements of the sewage handling circuit i.e. whilst keeping the main body portion 16 1 in-line. It is a noteworthy feature of the present invention that the construction of the hall valve 10 1 is such that the inlet 32 1 and outlet 34 1 are in line-of-sight relation to each other, meaning that when the ball 70 1 is removed or in its second position, if one were to look in the inlet 32 1 , one would be able to see out of the outlet 34 1 . This feature together with angling of the valve seat 46 1 to the longitudinal axis of the main body portion 16 1 permits the direct flow of fluid through the valve 10 1 ; lessens the likelihood of blockages occurring; discourages the formation of vortexes in the fluid and minimises friction losses. Although the present invention has been described with heavy emphasis on a ball valve suitable for use in sewage handling, the principles of the present invention can be applied to other fields where it might be desirable to provide a ball valve which can be maintained whilst keeping it in-line.

Claims: A ball valve (10 1 ) comprising: a first body portion (16 1 ) having an inlet (32 1 ), an outlet (34 1 ) and an aperture (26 1 ); a second body portion (50 1 ) closing off the aperture (26 1 ) of the first body portion (16 1 ), said second body portion (50 1 ) being detachable from the first body portion (16 1 ), the first and second body portions together defining a chamber; a valve seat (46 1 ) in the first body portion (16 1 ) dividing the chamber into inlet (62 1 ) and outlet (64 1 ) regions; a ball guide (56 1 ) disposed in the outlet (64 1 ) region; a ball (70 1 ) movable between a first position in which it sits on the valve seat (46 1 ) and blocks fluid flow between the outlet (34 1 ) and the inlet (32 1 ), and a second position in which the ball abuts against the ball guide (56 1 ) and fluid can flow between the inlet (32 1 ) and the outlet (34 1 ), characterised in that : the ball guide (56 1 ) forms an integral part of the second body portion (50 1 ); and in that due to the size of the aperture (26 1 ) and the integral configuration of the ball guide (56 1 ) and the second body portion (50 1 ), on removal of the second body portion (50 1 ), immediate access is provided to the valve seat (46 1 ). A ball valve (10 1 ) as in Claim 1, where the aperture (26 1 ) is sized to permit the removal and replacement of the valve seat (46 1 ). A ball valve (10 1 ) as in Claim 1 or 2, wherein the inlet (32 1 ) and outlet (34 1 ) are disposed in line-of-sight relation to one another. A ball valve (10 1 ) as in any preceding claim, wherein the ball guide (56 1 ) includes two spaced abutments (58 1 ) which project into the first body portion (16 1 ).

Inventors: CLARKE BRENDON ALEXANDER, CLARKE, BRENDON ALEXANDER
Applicants: CLARKE BRENDON, CLARKE CARL, CLARKE CHERYL, CLARKE EDIT, CLARKE PETER, CLARKE RENE, CLARKE, BRENDON, CLARKE, CARL, CLARKE, CHERYL, CLARKE, EDIT, CLARKE, PETER, CLARKE, RENE
Application year: 1995
Main classification: F16K15
IPC codes: F16K15, F16K27