Patent ID: 7905382

Claim:
A wave soldering tank comprising: a tank body for housing molten solder, a discharge pump which is installed inside the tank body for pumping molten solder, a rotating shaft which is connected to and extends upwards from the discharge pump, a discharge nozzle installed inside the tank body for upwardly spouting molten solder which is sent to it by the discharge pump, a duct which is installed inside the tank body and which has the discharge pump installed at one of its ends and the discharge nozzle installed at its other end, an oxidation preventing member which has a through hole for passage of the rotating shaft with a gap therebetween and a hollow portion in its interior for producing buoyancy so that the oxidation preventing member will float above the discharge pump on the surface of molten solder, and an engaging mechanism which restricts rotation of the oxidation preventing member in a horizontal plane and comprises a plurality of stationary connecting rods which extend upwards in the interior of the tank body along the outer periphery of the oxidation preventing member, wherein the oxidation preventing member comprises a top plate, a bottom plate spaced from the top plate, and walls extending between the top and bottom plates and forming at least one sealed chamber along a periphery of the oxidation preventing member for imparting buoyancy to the oxidation preventing member, and the oxidation preventing member has a size which is larger than any swirling flows which form in the periphery of the rotating shaft and which is such that the oxidation preventing member is not affected by molten solder which spouts from the discharge nozzle and falls downwards.