1 The invention is related to a composition to be used in gravitation casting of liquid metal including a dose valve with eccentric opening function with power torque.

Gravitation casting of sink anodes, for example, volume and weight are a very important part of the casting to reduce supplementary work with the product as much as possible.

The invention solves the following problems: accuracy dose amounts, it is functional under high temperature, dose chamber can be changed while there is still liquid metal in the tank, components can be changed individually in the valve and the valve can be put in a production line where the valve will operate all at the same time by using for example only one electro engine with an axel with pressure plates that move in both directions serving all the valves simultaneously.

Earlier known engineering in the area is presented in the Patent WO 90/12667 and describes a metal casting apparatus that consists of an expired pipe or a funnel that has an entrance formed with a valve element that can be moved in longitudinal direction of the discharge pipe. The valve element is expanded in one end so that it can function with the valve seat to close or open the discharge pipe when the valve element moves up or down.

An inquiry with known valve suppliers about using valves when pouring liquid metal, the following explanations were given: In ordinary high temperature valves with control there are problems with pre-heating because they are not designed for this type of use.

The cause of the pre-heating problem is that the variation of the temperature can easily damage the valve and the control, and it would be very expensive to make it possible to control the temperature with high accuracy.

The dosing capacity was related to the valve's opening time, something that could be a problem with casting alloys that have a liquid temperature of approximately 500 °C which is also the operative temperature of the valve.

Because of the metal ductility in the range of the metal's liquid and solid state, it is very possible that the valve will malfunction.

It was notified that the valve had not been used for gravitation casting of liquid metal before, so one could not give any guarantee for the functionality of the valve.

The construction of this valve is based on the known ordinary valve principle, but to achieve all the already mentioned characteristics, the valve is built as shown in fig. A.

This dose valve is not so temperature sensitive, and therefore the valve chamber and outlet can be held well beyond melting temperature so that the liquid is flowing easily, and the walls inside the valve as shown in fig. C. are sloping towards the outlet to limit the deposit of liquid metal inside the valve.

Because of the cone design of the inlet valve (5) and inlet chamber (6) also the outlet valve (3) and dose chamber (4), a possible expansion in the metal will not cause the valve to jam between chamber and valve. Thus the valve will function even when temperature variation occurs in the valve.

The valve and pouring tank are supposed to be pre-heated with, for example, Propane.

This makes it very easy and cost effective to solve the problem of pre-heating of this valve.

The control unit located on top of the tank is also designed in accordance with the temperature.

Because of the thermal conductivity in the valve, the control unit is designed in a way so that the heat does not spread further than the pressure points of the control. The control of the valve is located on top of the tank fig. B. shielded from the high temperature, and arranged so that it is possible to control the valve simply with for example an electro engine that moves in both directions with pressure plates that open and close the dose chamber.

The valve control fig. D. is designed with compression springs (14,20) that keep the inlet valve (5) and outlet valve (3) closed. A valve opening unit (17,23) connected to the counterweight unit (11,12), has 3 calculated purposes: 1. Maintain as well as possible centric pressure on the valves (3,5) 2. Move the pressure points away from the valves (3,5) so they can be more easily controlled.

3. Increase moment pressure to open the valve.

To control the fluctuation of the opening of the valves (3,5), it is intended to use a regulated distance unit (10) to prevent the valves from opening too much so that the valve is damaged.

In order to achieve dose accuracy amounts, a dose chamber (4) is to be used.

The dose chamber (4) can be changed while there is still molten metal in the tank without any leak from the tank, an issue with for example casting of small series.

The lower parts of the valve (7,6, 4) can also be manufactured as flange plates with a centre hole for the inlet valve (5), the dose chamber (4) and the outlet valve (3) that are attached together with screws, nuts and packings.

The whole valve consists of independent components that can be changed separately.

This makes the valve easy to maintain with less functioning disorder.

Composition for gravitation casting of liquid metal including a dose valve that consists of an inlet chamber (6) and a dose chamber (4) that for example are screwed together, and the inlet valve (5) and outlet valve (3) which makes the filling and outlet function of the valve characterised by that the outlet valve rod (3 a) that goes centric inside the inlet valve rod (5a) and inlet valve (5) and outlet valve (3) that affiliate the openings in the inlet chamber (6) and dose chamber (4) thus becoming a dose valve.

More characteristics regarding the invention are listed in the demands 2-7.

The use of the composition regarding demands 1-7 is limited to gravitation casting of liquid metal.

The valve, according to the invention, is shown in the drawings, where fig. A is a side sketch of the completely mounted valve, fig. B is a side sketch of the valve installed in a tank, fig. C is a sketch of the lowest part of the valve and fig. D is a side sketch of the control unit on the of the tank.

The description is based on fig. C and fig. D. At the bottom of the dose valve a funnel (1) is mounted. The funnel (1) is attached without further description to a short stub with external threads that are turned out of the lowest part of the dose chamber (4).

The upper part of the funnel is shaped like a hexagon so it is easier to disassemble and assemble with an Allen wrench.

The dose chamber (4) is also externally shaped like a hexagon so it will be easier to change the chamber under operation.

The chamber has internal threads so it can be screwed to the inlet chamber (6). The important element regarding the dose chamber (4), is that the length of the chamber is constructed so that the calculated volume inside the chamber will add up with the calculated volume and weight of the moulded product.

The inlet chamber (6) has external threads so that the dose chamber (4) can be screwed on to the inlet chamber (6). The inlet chamber (6) is also externally shaped like a hexagon on the part that does not have external threads. The inlet chamber (6) has internal threads so it can be screwed on to the short pipe with external threads that will be welded on to the fitted opening at the bottom of the tank.

It is calculated that the joints will not be against the current flow from the pipe with external threads (7) all the way down to the funnel (1).

The outlet valve rod (3a) is shaped so that the rod goes inside at the centre of the inlet valve rod (5a), and is attached to the valve control at the top.

The valve control at the top of the tank is shaped as follows: The first element we start with is the main platform (9) for the valve control. The valve rods (5a, 3a) are supported by a steering pipe (8) to prevent the valves from moving out of position sideways.

The compression spring (14) will make sure to close the inlet valve (5) of the inlet chamber (6). The upper part of the inlet valve rod (5 a) will have external threads so that a nut (16) can be screwed on to the rod together with a pressure equalization disc (15) between the nuts (16).

This composition will also function as an adjustment of the tightening of the valve.

It is calculated to use a lever principle to operate the valve function. This function is obtained with a counterweight rod (12) that is attached to the s-formed valve opening rod (17). To prevent the inlet valve (5) from smashing into the outlet valve (3) it is calculated to have an adjustable distance rod (10) that is adjusted to the calculated fluctuation of the inlet valve (5).

The control of the outlet valve (3) will be manufactured as follows: 4 pieces of distance rods (13) (externally shaped like a hexagon) attached with internal threads in the main platform (9) and with nuts (19) to the pressure spring platform (18). The compression spring (20) is supposed to hold the outlet valve closed and also reverse the valve to the original position after opening. The outlet valve rod (3a) is externally threaded at the upper part and it is screwed on to a nut (21) together with a pressure equalization disc (22) in between.

To open the outlet valve (3) it is calculated to use a valve opening rod (23) together with a counterweight rod (11) and an adjustable distance rod (10) to control the fluctuation of the opening of the valve.

The lower parts of the valve (7,6, 4) can also be manufactured as flange plates with a centre hole for the inlet valve (5), the dose chamber (4) and the outlet valve (3) that are attached with screws, nuts and packings.