UNDER VACUUM AND OVER PRESSURE

The Related Art

The invention relates to sprueless casting machine unit with lost wax method under vacuum and over pressure used in shaping of precious metals such as gold and silver.

The present invention relates to a moulding unit performing without sprue production by using adequate amount of materials for moulding and preventing waste of precious metals by means of a thruster component (piston) integrated to the moulding unit of the lost-wax casting machine.

The Prior Art

Nowadays, lost-wax casting is used for melting and shaping of precious metals such as gold and silver. Moulds and designs of various visual qualities can be obtained by lost-wax casting. For instance, a plaster mould comprising wax moulds is formed for obtaining desired shapes out of precious metals as a result of moulding and thus moulding multiple numbers of bracelets, earrings, rings, and various kinds of jewelleries in a casting machine. Afterwards, when this plaster mould is heated under high temperature in a blast furnace, the wax moulds found in the plaster mould melt down and moulds are formed instead of the molten waxes. Afterwards, by means of melting and pouring precious metals such as gold and silver into this mould, the molten precious metal would fill in the plaster mould and thus gets moulded and take the shapes of ring, earring etc. jewelleries. In the next step, the plaster mould is broken and the shaped state of the products is revealed. After the plaster is broken, just like a tree, the rings, earrings and similar precious metals found at the tree branches are collected by cutting by a cutter.

In the prior art, for shaping precious metals, after a mould is formed in a desired shape, the precious metal is melted and directly poured into a mould. After the mould is broken, raw material waste occurs, since the main body and branches, and especially the root part are scrapped. Therefore, this waste negatively affects the production costs.

In the known status of the art, labour costs also increase, since the product is obtained by cutting the main body and the branches. In the known status of the art, the rate of wastage is high, since the products are removed from the branches by cutting, and in order to reuse the remaining parts after cutting the products, these parts are required to be re-melted (and element addition can be made after re-checking the alloy values), which increases the production costs. Moreover, while cutting thin pieces, it causes bending of the product. It causes loss of time due to cutting and causes wastage due to repeated melting of the scrapped parts. Besides, since it causes combustion of passive ingredients found in the metal, the metal loses its characteristics and may be broken or become useless.

In a patent search made about the prior art, a patent document No. US4571270 is encountered. In this application; a rotating mould embodiment is disclosed. It comprises a carrier that is mounted to the wax intake tank. It comprises a carrier that is rotated 180 degrees for melting the wax found in the mould tank and recovering its original state.

In another patent with No. US6349758, a root line and branches for the flow of precious metal into mould spaces formed by lost-wax casting in a plaster mould is disclosed. In addition, a root part that is evacuated in order to form the body at the root part is disclosed and a demountable piece is disclosed which is mounted to the root part modularly such that it would fill the root.

Purpose of the Invention

The purpose of the invention is to eliminate the technical problems encountered in the prior art lost- wax casting machine moulding units, and provide a without sprue casting operation.

The purpose of the invention is to ensure filling precious metals directly into mould chambers found in the mould. In this way, metal would not be filled into the main flow line named sprue where extra metals are filled unnecessarily into mould chambers. As a result, adequate (required) amount of raw materials would be used and thus production costs would be minimized.

The purpose of the invention is to ensure filling of only the branches and the product part in the main body found in the mould and thus prevent use of unnecessary raw materials in the main body.

Another purpose of the invention is to use a thruster component or a piston-type means in order to ensure filling of the required mould spaces without filling the raw materials (gold, silver etc. precious metals) into the main body.

Another purpose of the invention is to eliminate the extra cutting operation following moulding at a certain level by means of using adequate amount of raw materials with the novel lost-wax casting machine having a piston structure. In this way, it is aimed to reduce workmanship and time costs. Another purpose of the invention is to prevent high material waste, eliminate loss of time and electricity, and prevent reduction of efficiency due to operating with high rate of scrap products. Moreover, the purpose is not to wait the cooling time especially in precious metals.

Another purpose of the invention is to ensure filling of only the required parts of the main body, instead of filling the whole main body, during the flow of precious metals, and prevent the precious metal from staying idle when the main body stays idle at the end of the operation with the downward movement of the piston.

Another purpose of the invention is to fill the raw material into moulds gradually from top to bottom. However, in the prior art, the raw material is filled into the moulds from bottom to top. Therefore, a different filling technique is provided with regard to the prior art technique.

In order to achieve the above said purposes, the invention comprises a thruster component or a PLC-controlled actuator having a motion shaft, which meets said molten metal found in fluid state at the flow line, and gradually brings down the fluid-state metal such that it would be filled into the flow branches.

Brief Description of the Figures for Better Understanding of the Invention

Figure 1 is the general perspective view of the whole lost-wax casting machine according to the present invention.

Figure 2 is a close-up perspective sectional view of the moulding unit according to the invention. Figure 3 is two-dimensional sectional front view of a moulding unit according to the invention.

Figure 4.1 is a representative sectional view of the movable shaft first stage in the moulding unit.

Figure 4.2 is a representative sectional view of the movable shaft second stage in the moulding unit.

Figure 4.3 is a representative sectional view of the movable shaft third stage in the moulding unit. Reference Numbers

100. Lost-wax casting machine 30 120. Moulding unit

1 1 1 . Bearing components 121 . Main block

1 12. Main body 122. Mould chamber

1 13. Lower carrier body 123. Plaster mould 124. Flow line 150. Thruster component

125. Flow branches 151 . Motion shaft

126.Shaft transfer space 152. Centering intermediate piece

130. Metal melting section 153. Bearing component 131 . Melting chamber 160. Present pistons

132. Resistance 161 . Lower table

133. Metal

Detailed Description of the Invention

Figures 1 and 2 give the general perspective views of the whole lost-wax casting machine (100) according to the present invention. The invention is a lost-wax casting machine (100) moulding unit (120) comprising a melting chamber (130) in which gold, silver, and other precious metals are melted; and a moulding unit (120) having a mould chamber (122), into which the fluid-state metal (133) melted in said melting chamber (130) is poured for being moulded, and it is characterized in that;it comprises a thruster component (150) having a motion shaft (151 ), which meets said molten metal (133) found in fluid state at the flow line (124), and gradually brings down the fluid-state metal (133) such that it would be filled into the flow branches (125). Said thruster component (150) is preferably a piston, a motor, or a drive component that forms linear motion in y-axis. However, a piston is preferably used in this system.

It comprises a bearing component (153) enabling said thruster component (150) to move and be centered within the main block (121 ) and a centering intermediate piece (152) which ensures guiding of said thruster component (150) motion shaft (151 ). In addition, it comprises a mould chamber (122) having a shaft transfer space (126) enabling linear motion and transfer of said thruster component (150) motion shaft (151 ) in y-axis. On the other hand, the motion shaft (151 ) used in the system has ceramics, glass, stainless iron, carbon graphite coal, titanium, and material durable against temperature differences. Moreover, usage of an internal spring and an external spring (71 ) surrounding the piston shaft that is connected to the piston head (41 ) positioned inside the plaster mould (123) is also possible. This internal spring and external spring (71 ) preferably comprise titanium material. This spring is a wide-step compression spring, which facilitates the linear motion of its shaft in the flow line without hitting the side walls, prevents the plaster mould from breaking or cracking, and found within the mould beforehand. The way of operation of the thruster component (150) integrated into the mould chamber (122) of the lost-wax casting machine (100) and the novel production method is as follows.

As disclosed in Figure 3, the molten metal (133) that is brought into fluid state by means of the resistance (132) is poured into the mould chamber (122) of the moulding unit (120) through the flow line (124). The plaster mould (123) found within the mould chamber (122) is the mould spaces left from the waxes melted in the mould chamber (122) by means of melting the moulds that previously had wax in them, in a furnace. These moulds are moulds that contain earrings, rings, and similar jewelleries. The molten metal (133) is poured into the plaster mould (123) through the flow line (124). However, the fluid-state metal (133) is met at the flow line (124) by the movable shaft (151 ) of the piston, i.e. the thruster component (151 ). In other words, the fluid-state metal is not directly filled into the plaster mould (123) as in the prior art. In the new technique, it is brought down gradually from the top to the bottom via the movable shaft (151 ). The fluid-state metal is filled into the flow branches (125) by being brought down gradually in this way. Figure 4.1 shows a representative sectional view of the movable shaft (151 ) first stage in the moulding unit (120). The movable shaft (151 ) that meets the molten metal (133) from the first stage ensures bringing the movable shaft (151 ) down gradually in the y-axis by means of the software (an actuator) integrated into the PLC system of the machine. The metal (133) filled into the flow branches (125) in the first stage is then filled into the lower flow branches (125) in the second stage and then the fluid-state metal (133) is filled into the lower flow branches (125) in the third stage. In this way, the metal (133) in the needed amount and predetermined basis weight is melted and filled into the moulds without the need for use of unnecessary amount of precious metals (133).

The new production method comprises the operation steps of: - melting of said gold, silver, and other precious metals in the melting chamber (131 ), pouring the molten metal (133) through the flow line (124) while it is in fluid-state,

- the movable shaft (151 ) meeting/receiving the fluid-state metal,

- the fluid-state metal (133) being gradually brought down via the movable shaft (151 ) such that it would be filled into the flow branches (125), and - bringing down said movable shaft (151 ) through the flow line (124) from y1 starting point to y2 ending point in y-axis in a speed and level determined by the software that is integrated into the PLC system.