Patent GB-1249480-A (GB)
Title: Valve assembly
IPC: C02F1/42
Filed: 1968-11-01
Abstract: 1,249,480. Ion-exchange; valve assembly for water softening apparatus. ECODYNE CORP. 1 Nov., 1968 [1 Nov., 1967], No. 51817/68. Heading B1J. [Also in Division F2] A valve arrangement for controlling liquid flow in for example ion-exchange apparatus for softening water comprises a valve assembly which is housed within a passage in a manner such as to be axially moveable therein between an "up" position, an intermediate position and a "down" position and which includes a first valve member and a second valve member, the first valve member having formed therein an aperture to permit liquid flow therethrough and the second valve member being movable in the aperture of the first valve member to open the aperture when the valve assembly is in the "down" position; three valve seats are axially spaced in the passage in a manner such that the first valve member is adapted to seat against a first valve seat when the valve assembly is in either the intermediate position or the "down" position and against a second valve seat when the valve assembly is in the "up" position and the second valve member is axially movable to seat against a third valve seat when the valve assembly is in the "down" position. Such a valve assembly is illustrated in Figure 7 which shows a fragment of a valve arrangement, see Figures 2 to 6 (not shown), which comprises further valves/valve assemblies and which is used for controlling liquid flow in water softening apparatus, see Figure 1 (not shown). As illustrated in Figure 7, the valve arrangement comprises a valve base 30, a valve head 31 and a valve assembly 125. The valve base is provided with a passage lined with a sleeve 60 having a bore 66 communicating via apertures 65 with passage 67 and via chamber 78 with passage 75 and with port 190. The first valve seat is constituted by an annular end surface 61 of the sleeve; the second valve seat is constituted by an annular end surface 84 of a fitting 80 which is threadably connected with the valve head and which is provided with a bore 83 communicating with a passage 82, the surface of the fitting defining the bore being provided with a flange 81 which constitutes the third valve seat. The first valve member comprises a valve disc 135 provided with an aperture 136 and with a lip 137 which constitutes an aperture valve seat. The second valve member comprises a pin 126 extending through the aperture in the valve disc and through a bore 127 provided in the valve head and in a plate 108 mounted thereon, an O-ring 129 providing a seal between the valve head and the pin which has a section of large diameter, a section 131 of reduced diameter, a section 132 of varying diameter, a section 133 of normal diameter and an enlarged foot portion 134 constituting stop means. As illustrated in Figure 7, the valve assembly is in the "down" position, the pin section of reduced diameter being disposed in the aperture in the valve disc to permit liquid flow therethrough and the pin section of large diameter being seated against the third valve seat; when the valve assembly is in either the "up" position or the intermediate position, the pin section of normal diameter is disposed in the aperture in the valve disc to prevent liquid flow therethrough and the pin section of large diameter is not seated against the third valve seat. Surrounding the pin section of large diameter is a snap ring 138 and a spring 139 which co-operate to bias the valve assembly to the "up" position; surrounding the pin section of reduced diameter is resilient means in the form of a spring 140 which acts to bias the pin stop means towards the valve disc so that the pin section of normal diameter seats against the aperture valve seat to occlude the aperture in the valve disc.