KR101220890B1 - Centrifugal casting apparatus for manufacturing copper cage rotor and centrifugal casting method the same - Google Patents

Abstract

The present invention relates to a centrifugal casting apparatus for manufacturing a cage rotor, and more particularly, has good electrical conductivity, and prevents the occurrence of fine pores during the manufacture of a cage cage rotor made of copper with high melting temperature, thereby reducing the defective rate. It relates to a centrifugal casting apparatus for producing a copper strip rotor, and a centrifugal casting method thereof.
The present invention provides a core having a hole in the center and at the same time the iron piece is provided with slits in the peripheral portion laminated in the axial direction; A lower heat insulating mold having a core seated in an axial direction and having a cavity engaged with a lower portion of the core, and a lower mold which externally couples the lower heat insulating mold; An upper mold engaged with the lower insulating mold in an axial direction, the upper insulating mold surrounding the core, and the upper insulating mold coupling the upper insulating mold from the outside and engaged with the lower mold; A gate part positioned in the upper mold and into which molten metal is injected; And an eject pin seated through the bore formed in the core and forming a cavity with the upper insulating mold, wherein the eject pin includes at least one air outlet for discharging air in the mold as the molten metal is injected. It features.

Description

CENTRIFUGAL CASTING APPARATUS FOR MANUFACTURING COPPER CAGE ROTOR AND CENTRIFUGAL CASTING METHOD THE SAME}

The present invention relates to a centrifugal casting apparatus for manufacturing a copper cage rotor, and more particularly, to good electrical conductivity, to prevent the occurrence of micropores during molding of the cage rotor of a copper material having a high melting temperature, thereby reducing the defective rate. The present invention relates to a copper concentrated rotor control centrifugal casting apparatus and a centrifugal casting method thereof.

In general, a squirrel cage induction motor employing a squirrel rotor is made of a copper or aluminum round bar in a conductor iron core, and both ends thereof are short-circuited by circular side plates. Therefore, it is widely used in large capacity pumps and compressors adopting building equipment, home appliances, and the like.

Looking at the manufacturing example of the cage rotor according to the prior art described in Korean Patent Application No. 2004-7010092, as shown in Figure 1, the stack pile 1 is located inside the mold (2) located in the vertical direction, The mold 2 is provided with annular upper and lower cavities 2a and 2b, and an inflow channel 2c into which aluminum can be injected is opened. At this time, the stack dummy 1 has a bore 1a formed at the center thereof, and a plurality of channels 1b are provided at the periphery thereof.

Thus, the stamping pins 3 are fitted into the bores 1a of the stack pile 1, the stack stack 1 and the stamping pins 3 are inserted into the mold 2, and then aluminum or predetermined Other alloys are injected. This molten metal penetrates the channels 1b of the stack pile 1 and fills the lower cavity 2b, the channels 1b, and the upper cavity 2a, and the mold 2 rotates about the center line. The metal is cooled. Then, when the stamping pin 3 is separated from the stack pile 1, the stack stack 1 includes a cage corresponding to the channels 1b and an image corresponding to the upper and lower cavities 2a and 2b, respectively. The lower ring is created.

In the centrifugal casting facility for manufacturing the cage rotor according to the prior art as described above, when the molten metal is injected between the molds, the air inside the molds flows out along the flow path through which the molten metal is injected. There is a problem that the internal air does not escape, and as the molten metal is cooled in such a state, fine pores exist in the upper / lower rings to increase the defective rate and further reduce the efficiency of the cage rotor.

The present invention relates to a centrifugal casting apparatus for a cage rotor, and a method thereof, and more particularly to a centrifugal casting apparatus for manufacturing a cage rotor and a centrifugal casting method thereof capable of preventing micropores from occurring in an end ring and reducing a defective rate.

In addition, the present invention is to form a cage and the end ring of the cage rotor of the good electrical conductivity, the object of the production of the cage rotor with good efficiency.

The present invention provides a core having a hole in the center and at the same time the iron piece is provided with slits in the peripheral portion laminated in the axial direction; A lower insulating mold having a core seated in an axial direction and having a cavity engaged with a lower portion of the core, a lower mold coupling the lower insulating mold from the outside; an upper insulating mold axially engaged with the lower insulating mold and surrounding the core; An upper mold coupling the upper insulating mold from the outside and engaged with the lower mold; A gate part positioned in the upper mold and into which molten metal is injected; And an eject pin seated through the bore formed in the core and forming a cavity with the upper insulating mold, wherein the eject pin includes at least one air outlet for discharging air in the mold as the molten metal is injected. It features.

In addition, the present invention is characterized in that the eject pin includes a shaft passing through the bore, a head coupled to one end of the shaft, and a nut coupled to the other end of the shaft.

In addition, the present invention, the head includes a molten metal guide portion having an inclination to guide the molten metal entering the furnace, and an end ring forming portion that is bent from the molten metal guide portion to form a cavity with the upper insulation mold, the cavity is Opening is characterized in that the molten metal is introduced.

In addition, the present invention is characterized in that the air outlet is formed in at least one of the shaft and the nut.

In addition, the present invention is characterized in that the molten metal is made of a copper material.

In addition, the present invention is characterized in that the centrifugal casting apparatus includes a suction device for more effectively discharging fine air through the air outlet.

In addition, the present invention, the lower insulating mold comprises a stepped portion for supporting the eject pin, characterized in that the air outlet is formed in the stepped portion.

In addition, the present invention is characterized in that the upper mold and the upper insulation mold and the lower mold and the lower insulation mold are formed in the communication hole and the air outlet are in communication with each other so as to discharge the air.

In addition, the present invention, the air outlet of the insulating mold is characterized in that the porous material which can only take out air is press-fitted.

In addition, the present invention, in the centrifugal casting method for manufacturing the squiggly rotor to form the upper end ring and the lower end ring integrally as the molten metal is injected into the core seated on the upper mold and the lower mold, the core with the eject pin The first step is seated on the lower insulating mold is fitted to the lower mold; A second step of coupling the upper mold into which the upper insulating mold is fitted; A third step of injecting molten metal between the upper mold, the lower mold, the eject pin, and the core engaged with each other in the second stage, and simultaneously discharging air; When the molten metal is solidified in the fourth step, the upper mold and the lower mold are disassembled, and the eject pin is separated from the core.

In addition, the present invention is characterized in that the molten metal is introduced into the core through the gap between the eject pin and the upper insulation mold in the third step, and the air escapes through the air outlet formed in the eject pin.

In addition, the present invention is characterized in that the eject pin is separated as the molten metal solidifies in the fourth step and the gate formed integrally with the core is removed.

In the centrifugal casting apparatus and the centrifugal casting method for manufacturing the cage rotor according to the present invention configured as described above, when the molten metal is injected into the molds, the air inside the molds to the outside through the air outlet provided in the shaft and the molds Since it is discharged, even if the molten metal is injected quickly, less air escapes to prevent micropores from occurring, thereby reducing the defect rate and further increasing the efficiency of the cage rotor.

In addition, since the mold can be easily produced, the cage rotor can be manufactured by the centrifugal casting method, and thus there is an advantage that the cost can be reduced.

In addition, there is an advantage that the molten metal is not easily solidified even when the cage rotor is formed by using a material having a high melting point by the heat insulating mold in the mold to reduce heat loss.

In addition, since the squirrel rotor is made of copper having excellent electrical conductivity, there is an advantage of increasing the electric efficiency of the motor.

1 is a view showing a cross section of the cage rotor according to the prior art.
Figure 2 is a view showing a cross section of the centrifugal casting device for a cage rotor according to the present invention.
3 is a view showing a combined state of the centrifugal casting mold according to the present invention.
4 is a view showing a core according to the present invention.
Figure 5a is a view showing the separated state of the eject pin according to the present invention, Figure 5b is a view showing a cross section of the combined eject pin.
Figure 6a is a view showing a top view of the lower insulating mold according to the present invention, Figure 6b is a view showing a cross-section of the lower insulating mold is formed air outlet.
7 is a view showing another example in which an air outlet according to the present invention is formed.
Figure 8a is a view showing a state in which the cage rotor according to the invention separated from the mold, Figure 8b is a view showing the cage rotor in accordance with the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 and 3 is a view showing a centrifugal casting apparatus for manufacturing a cage rotor according to the present invention, Figure 4 is a view showing a core according to the present invention, Figure 5 is a view showing an eject pin according to the present invention.

As shown in FIG. 2 and FIG. 3, the centrifugal casting apparatus 100 includes molds 110 and 120, heat insulating molds 130 and 140, a core 150, and an eject pin 160. First, in the centrifugal casting apparatus, the upper insulation mold 130 is positioned inside the upper mold 110, the lower mold 120, and the upper mold 110, and correspondingly to the lower mold 120. The lower insulating mold 140 is combined. After installing the lower insulating mold 140, which is a heat insulating material, in the lower mold 120 and placing the core 150 therein, after the upper mold 110 and the fastening means are joined to each other, the molten metal is poured into the molten metal 131 and the hot water path 132. It also includes a number of other components to be cooled while rotating in the injected state.

More specifically, the upper insulating mold 130 and the lower insulating mold (130) to prevent solidification due to heat loss into the mold when the inflow of the molten copper material molten metal inside the upper mold 110 and the lower mold 120 ( 140 is inserted into a shape corresponding to each mold, the circumferential cavity 141 is formed at the lower end of the lower insulating mold 140 so that the lower end ring 156 is formed in the core 150. . The upper end ring 155 is molded by a shape made by the head 161 of the eject pin 160 to be described later and the upper insulating mold 130. In order to join the upper mold 110 and the lower mold 120, the coupling parts 111 and 121 extending on opposite sides and protruding in the radial direction are formed, and the coupling parts are formed on the circumferential surface of each mold ( 111 and 121 are preferably located plurally in symmetry. In addition, the lower mold 120 is provided with a mounting portion 123 that can be centrifugally cast in combination with a centrifugal machine (not shown) to protrude in a radial direction. Since the upper insulation mold 130 is inserted into and inserted into the upper mold 110, the molten metal is injected into the molten metal 131 formed in the upper insulation mold 130. The lower mold 120 has a through hole 126 through which the nut 168 of the eject pin 160 to be described later penetrates and is supported, and the lower insulating mold 140 also extends to the through hole 126 to be nut 168. ) To form a stepped portion 142 to radially support. In addition, the stepped portion 142 forms a cavity 141 for forming the lower end ring 156 in the core 150.

In addition, the upper insulating mold 130 and the lower insulating mold 140 is heat transfer to the mold when the inflow of the molten metal, and serves as a heat insulating material to prevent the molten metal from hardening.

4 is a view showing a core according to the present invention, the core 150 is provided with a hole in the center and at the same time the iron piece 151 having slits at the periphery is configured to be stacked in the axial direction, the center as the iron pieces are stacked The bore 152 is provided, and the periphery of the channel 153 through the axial direction is provided. At this time, when the molten metal is filled in the channels 153 of the core 150, the cage 154 is generated. Although molten aluminum is conventionally used, it is preferable to use copper having excellent electrical conductivity, and when copper is used, the electrical efficiency is increased by about 2 to 4%. Typically, the iron piece 151 uses a silicon steel sheet, and is heated to prevent the molten metal injected into the heat-insulating mold 130, 140 so as not to solidify due to heat loss, and to heat in a nitrogen atmosphere so that the insulating coating is not lost. Prevent oxidation and heat up to a temperature at which no phase transformation occurs.

As shown in FIG. 5, the eject pin 160 includes a head 161, a shaft 165 connected at one end to the head, and a nut 168 connected at the other end of the shaft. The head 161 is made of a heat insulating mold material and is formed in a conical shape so that the radius thereof is widened from the upper part to the lower part, and extends to the melt guide part 161a and the melt guide part 161a for guiding the melt and to have a smaller radius. It is bent to form an end ring forming portion (161b) for forming the upper end ring (155). That is, the molten metal guide 161a is inclined to form the lower end ring 156, the cage, and the upper end ring 155 of the core 150 to form a gap with the upper insulating mold 130. The end ring forming portion 161b corresponds to the upper insulating mold 130 to form a cavity in which a cylindrical gap in which the molten metal is injected is formed. A coupling groove 162 is formed at the center of the rear surface of the head 161 so as to be screwed with the shaft 165, and a shaft support groove 163 is formed in the coupling groove 162 to support the shaft. . A thread 162a is formed on the inner circumferential surface of the coupling groove 162, and a thread 167a corresponding to the shaft 165 is formed at one end of the shaft 165 to be coupled to each other.

One end of the shaft 165 is provided with a head support 166 radially protruding from the head 161 when supporting the head 161 or serving as a stopper. It is fitted into the shaft support groove 163. The other end of the shaft 165 is formed with a thread 167b to engage with the shaft nut 168, and the thread 169b is formed so that the hole 169 of the shaft nut can also be coupled to the other end of the shaft. The eject pin 160 configured as described above is fitted to the entire bore 152 of the core 150, thereby preventing the bore 152 dimension of the core 150 from being deformed in the centrifugal casting process.

In addition, a plurality of air outlets 170a may be formed in the shaft 165 of the eject pin 160 to prevent micropores from being injected into the molten metal. In the casting operation, when the molten metal is poured into the spout and the micropores existing in the mold are not removed in the process of manufacturing the molding, the micropores remain in the molding. These micropores not only increase the defective rate of the molding, but also shorten the life of the molding. Accordingly, this problem may be solved by forming air outlets 170a in the shaft 165. In addition, in the cylindrical nut 168, the air outlet 170b may be formed on the outer circumferential surface to enhance the micropore discharge effect. At this time, by connecting the suction device (not shown) to the centrifugal casting device, it is possible to more smoothly discharge the fine air through the air outlet (170a, 170b).

In this way, when the mold is rotated by the centrifugal machine after the air outlets 170a and 170b are formed so that the molten metal enters through the pouring holes and is filled from the lower part of the mold to the furnace 132, the air present in the mold is the core. It passes through the air outlets 170a and 170b formed in the shaft 165 or the nut 168 through the minute gap of the 150.

6 is a view showing a state in which the air outlet is formed in the lower insulating mold in accordance with the present invention, Figure 7 is a view showing a state in which the air outlet is formed in the mold and the insulating mold in accordance with the present invention.

Referring to FIG. 6, FIG. 6A is a view of the lower insulating mold from above, and FIG. 6B is a view of a cross section. As the molten metal is injected through the pouring hole 131, the air outlet 145 communicating with the cavity 141 may be formed to allow the air existing in the cavity 141 of the lower insulation mold 140 to escape. Preferably, the air outlet 145 is formed in plural along the circumference, and may be variously configured to discharge only air. In addition, by injecting a porous material into the air outlet 145, the molten metal does not escape, but may be configured to escape the air.

Referring to FIG. 7, an air outlet 145 communicating with the lower mold may be formed at an opposite side corresponding to the stepped portion 142 forming the cavity 141 of the lower insulation mold 140. It is preferable to be formed along a circumference of the lower insulation mold, and as described above, the porous material is press-fitted into the air outlet 145, so that only air can escape. At this time, the lower mold and the lower insulation mold are distorted during rotation by the centrifugal machine, so that the communication hole 125 formed in the lower mold 120 and the air outlet 145 of the lower insulation mold 140 may not communicate with each other. Therefore, when the projection (not shown) is formed on the lower surface of the lower insulating mold and the groove (not shown) is formed and fixed on the lower upper surface of the lower mold 120, it is possible to prevent the possibility of being twisted and communicated.

In this case, as described above, the upper mold 110 and the upper insulation mold 120 also have communication holes 115 and an air outlet 135 formed on the side to discharge air existing in the mold to the outside, and the upper insulation An air outlet may be formed at an upper side of the cavity of the mold 130, and a through hole may be formed in the upper mold 110 to communicate with the air outlet.

As shown in FIG. 8, the process of manufacturing the squirrel rotor by the centrifugal casting method includes coupling the lower mold 120 to the centrifugal machine, engaging the upper mold 110, and pouring the molten metal 132 into the molten metal. As it is injected along the air inside the molds through the air outlet (170a, 170b, 135, 145) and the molten metal is filled in the molds.

That is, after the lower mold 120 coupled with the lower insulation mold 140 is coupled through the centrifugal machine and the fastening part 123, and the core stack 150 is seated on the lower mold 120, the upper insulation mold The upper mold 110 to which the 130 is coupled is screwed through the lower mold 120 and the coupling parts 111 and 121. At this time, the core laminate 150 is heated in advance so as not to solidify due to heat loss when the inflow of the molten metal is put into the insulating mold, the centrifugal machine, the lower mold 120, the core 150, the eject pin 160, The upper mold 110 is engaged to be stacked between the coaxial C. As the molds are engaged with each other, the upper mold 110 and the lower mold 120 rotate as the centrifugal machine is driven, and molten metal is injected through the molten metal 132, and the molten metal is injected into the cavity of the lower insulation mold 140. 141, the channels 153 of the core 150, the upper insulation mold 130, and the cavity and the water course 132 formed by the end ring forming portion 161b of the head 161 are sequentially insulated from each other. Air in the space between the molds exits through the air outlets 145 provided in the eject pin 160 or the insulating molds 130 and 140, and the air outlets 135 and 145 communicating between the insulating mold and the mold. . Therefore, the molten metal in the mold is densely filled by the centrifugal force, and the solidified solidification is carried out from the lower portion where the molten metal is filled to the upper direction.

Then, when the upper mold 110 and the lower mold 120 is separated, the molten solidified molding is integrally formed to cover the core 150, and the core 150 has a lower end ring 156 and an upper end ring ( 155 is integrally connected to the molding filled in the channel 153, the upper end ring 155 is integrally connected to the gate 157, which is a molten metal melted in the flow path 132 of the gate. At this time, after removing the gate 157 and removing the nut 168 of the eject pin 160 from the shaft 165, the eject pin 160 is separated by pulling out the head 161 from above, You can complete the former.

In the above, the present invention has been described in detail with reference to the embodiments of the present invention and the accompanying drawings. However, the scope of the present invention is not limited by the above embodiments and drawings, and the scope of the present invention will be limited only by the contents described in the claims below.

100: cage rotor 110: upper mold
120: lower mold 130: upper insulating mold
140: lower insulation mold 150: core
160: eject pin 170a, 170b: air outlet

Claims (12)

A core in which an iron piece having a hole in the center and a slit in the periphery is stacked in an axial direction;
A lower heat insulating mold having a core seated in an axial direction and having a cavity engaged with a lower portion of the core, and a lower mold which externally couples the lower heat insulating mold;
An upper mold engaged with the lower insulating mold in an axial direction, the upper insulating mold surrounding the core, and the upper insulating mold coupling the upper insulating mold from the outside and engaged with the lower mold;
A gate part positioned in the upper mold and into which molten metal is injected; And
And an eject pin seated through the bore formed in the core and forming a cavity with the upper insulating mold, wherein the eject pin includes at least one air outlet for discharging air in the mold as the molten metal is injected. Centrifugal casting device for producing a copper cage rotor.
The method of claim 1,
Eject pin is a centrifugal casting device for producing a copper squirt rotor, characterized in that it comprises a shaft passing through the bore, a head coupled to one end of the shaft and a nut coupled to the other end of the shaft.
The method of claim 2,
The head includes a molten metal guide portion having an inclination to guide the molten metal entering the molten metal, and an end ring forming portion which is bent and extended from the molten metal guide portion to form a cavity with the upper insulation mold. Centrifugal casting apparatus for producing a copper squirt rotor.
The method of claim 2,
An air outlet is formed in at least one of the shaft and the nut centrifugal casting apparatus for producing a copper cage rotor.
5. The method according to any one of claims 1 to 4,
The molten metal is a copper centrifugal casting apparatus for producing a copper thick rotor, characterized in that made of copper.
5. The method according to any one of claims 1 to 4,
The centrifugal casting apparatus is a centrifugal casting apparatus for producing a copper cage rotor, characterized in that it comprises a suction device for more effectively discharge the air in the mold through the air outlet.
The method of claim 1,
The lower insulating mold includes a stepped part for supporting the eject pin, and an air outlet is formed in the stepped part, wherein the centrifugal casting apparatus for manufacturing the copper strip rotor.
The method of claim 1,
The upper mold, the upper insulation mold, and the lower mold and the lower insulation mold are each formed in the communication hole and the air outlet communicating with each other so as to discharge the air, the centrifugal casting apparatus for manufacturing copper copper rotor.
9. The method according to claim 7 or 8,
The air outlet of the upper or lower insulation mold is a centrifugal casting apparatus for manufacturing a copper-type rotor, characterized in that the porous material which can only extract air is press-fitted.
In the centrifugal casting method for manufacturing a cage rotor, which integrally forms the upper end ring and the lower end ring as the molten metal is injected into the core seated on the upper mold and the lower mold,
A first step in which a core having an eject pin is mounted on a lower insulating mold fitted to the lower mold;
A second step of coupling the upper mold into which the upper insulating mold is fitted;
A third step of injecting molten metal between the upper mold, the lower mold, the eject pin, and the core engaged with each other in the second stage, and simultaneously discharging air;
And a fourth step of dissolving the upper mold and the lower mold and discharging the eject pin from the core when the molten metal is solidified in the third step.
The method of claim 10,
In the third step, the molten metal is introduced into the core through the gap between the eject pin and the upper insulation mold, and the air is drawn out through the air outlet formed in the eject pin.
The method according to claim 10 or 11,
In the fourth step, the ejection pin is separated as the molten metal is solidified and the gate integrally formed in the core is removed.

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