Valve device for venting die-casting moulds

Abstract

The valve device for venting die-casting moulds has a valve housing and a venting duct running between an inlet and an outlet. A force-receiving element, which is actuated by casting material, and at least two venting valves, which are operatively connected to the force-receiving element, are arranged in the venting duct. Each venting valve comprises a valve piston. The force-receiving element is provided with radial protrusions, which engage in a corresponding cut-out in the respective valve piston and effect a direct coupling between the respective venting valve and the force-receiving element.

1 . A valve device for venting die-casting mould, the mould having at least one valve housing and a venting duct running between an inlet and an outlet, at least one force-receiving element, which is actuated by casting material entering the mould, and at least two venting valves, which are operatively connected to the force-receiving element, each venting valve including a valve piston, the force-receiving element arranged in the at least one venting duct, wherein the force-receiving element is operatively connected directly to the valve piston of the respective venting valve without a separate intermediate element. 
     
     
         2 . The valve device according to  claim 1 , wherein the force-receiving element is arranged centrally between the valve pistons. 
     
     
         3 . The valve device according to  claim 1 , wherein the valve device has two venting valves, the two valve pistons of which are arranged in a plane with the force-receiving element. 
     
     
         4 . The valve device according to  claim 1 , wherein the force-receiving element is provided with radial protrusions, wherein each of the protrusions engages in a respective cut-out in the valve piston of a respective one of the at least two venting valves. 
     
     
         5 . The valve device according to  claim 4 , wherein the force-receiving element is formed integrally with the radial protrusions. 
     
     
         6 . The valve device according to  claim 1 , the force-receiving element being axially displaceable between a pushed-forward starting position and a pushed-back effective position, and the force-receiving element is configured, when in the starting position, to hold the valve pistons in a pushed-forward open position, and, when in the effective position, to hold the valve pistons in a pushed-back closed position, and the force-receiving element being loaded by at least one spring in the direction of the starting position of the force-receiving element, wherein the force-receiving element is provided with a pressure face, and the valve device is provided with a pressure space which at least partially surrounds the force-receiving element and is pneumatically loadable to exert a force, directed counter to the spring force, on the pressure face of the force-receiving element and to displace the force-receiving element into the effective position thereof and/or to hold the force-receiving element in the effective position. 
     
     
         7 . The valve device according to  claim 1 , wherein the force-receiving element has a cylindrical main body and a cylindrical head part, wherein the head part has a smaller diameter than the main body, and wherein the end face of the head part projects into the venting duct. 
     
     
         8 . The valve device according to  claim 6 , wherein the pressure face is formed on the force-receiving element at the transition from the cylindrical main body to the cylindrical head part. 
     
     
         9 . The valve device according to  claim 1 , wherein the valve device has an outlet chamber, which is integrated into the valve housing and into which the at least one venting duct opens, wherein the outlet chamber is connected to a flange which leads outwards. 
     
     
         10 . The valve device according to  claim 6 , wherein the valve device further comprises a spring-loaded pressure plate which is operatively connected to a plurality of pressure rods, wherein the plurality of pressure rods protrude from the front face of the housing when in a starting state, and wherein, when a sealing plate is fixed to the front face of the housing, the pressure rods push the pressure plate backwards counter to the force of compression springs of the spring-loaded pressure plate, and wherein, when the sealing plate is removed, the pressure plate pushes the force-receiving element together with the valve pistons forwards into the starting position. 
     
     
         11 . The valve device according to  claim 6 , wherein the force-receiving element travels an axial distance of between 1 and 7 mm to pass between the starting position and the effective position. 
     
     
         12 . The valve device according to  claim 1 , wherein the end face of a head part of the force-receiving element, which opens into the venting duct, has a diameter of between 5 and 25 mm. 
     
     
         13 . The valve device according to  claim 1 , wherein the venting duct has an inlet duct ( 5 ) which branches from a region of branching into a number of branches corresponding to the number of venting valves, wherein the force-receiving element is arranged in the region of the branching, and wherein a venting valve is arranged in the region of the end of the respective branch. 
     
     
         14 . The valve device according to  claim 13 , wherein the respective branch of the venting duct is provided with at least two deflections, wherein at least two deflections effect a change in direction of the inflowing casting material by at least 60°. 
     
     
         15 . The valve device according to  claim 13 , wherein the respective branch of the venting duct is provided with at least one material collection chamber, in the form of a dead end, for the advancing casting material. 
     
     
         16 . The valve device according to  claim 1 , wherein a block bushing is inserted into the valve housing, said block bushing being made of a harder material than the valve housing and being designed to accommodate and guide the force-receiving element and the valve pistons. 
     
     
         17 . The valve device according to  claim 2 , wherein the force-receiving element is provided with radial protrusions, wherein the respective protrusion engages in a cut-out in the respective valve piston. 
     
     
         18 . The valve device according to  claim 7 , wherein the pressure face is formed on the force-receiving element at the transition from the cylindrical main body to the cylindrical head part. 
     
     
         19 . The valve device according to  claim 14 , wherein the respective branch of the venting duct is provided with at least one material collection chamber, in the form of a dead end, for the advancing casting material. 
     
     
         20 . The valve device according to  claim 11 , wherein the force-receiving element travels an axial distance of between 3 and 5 mm to pass between the starting position and the effective position.