CN212792920U

CN212792920U - Wheel antigravity casting equipment with molten pool heat preservation stove

Info

Publication number: CN212792920U
Application number: CN202021748995.7U
Authority: CN
Inventors: 张虎; 张花蕊
Original assignee: Beihang University
Current assignee: Beihang University
Priority date: 2020-08-20
Filing date: 2020-08-20
Publication date: 2021-03-26
Anticipated expiration: 2030-08-20

Abstract

The utility model discloses a wheel antigravity casting device with a molten pool holding furnace, which comprises a mould, a molten pool holding furnace and a liquid lifting box; the central position of the furnace cover of the molten pool holding furnace is connected with a central liquid lifting pipe, a liquid lifting box is connected above the central liquid lifting pipe, a plurality of shunting channels communicated with the liquid lifting pipe are arranged in a box body of the liquid lifting box, each shunting channel is connected with a shunting sprue, the shunting sprue corresponds to the position right below a wheel mold rim and is communicated with a cavity inlet for pouring into a mold cavity, and the section of the shunting sprue is approximately matched with the shape of the cavity inlet of a casting mold at the mold filling position. The utility model discloses be adapted to the runner setting and annotate the mode at the side of the many runners under the rim of wheel, solved the single stalk technique long distance feeding effect of traditional jumbo size wheel poor, the difficult problem in the hard control solidification temperature field after the intensive cooling, improved the performance and the production stability of wheel, still shortened the production beat, improved the qualification rate of production efficiency and wheel.

Description

Wheel antigravity casting equipment with molten pool heat preservation stove

Technical Field

The utility model belongs to the technical field of the casting technique and specifically relates to a wheel antigravity casting equipment with molten bath heat preservation stove is related to.

Background

The light weight is one of the most important ways for saving energy and reducing emission of fuel automobiles and reducing consumption and increasing range of new energy automobiles, and light weight materials such as aluminum alloy and the like are used for replacing traditional steel materials, so that the light weight materials become necessary choices for the updating of automobile design. Aluminum alloys used in automobiles can be classified into cast aluminum alloys and wrought aluminum alloys, and the cast aluminum alloys are mainly used for manufacturing parts such as engines, clutch housings, wheels, chassis parts, and the like. With the demand for improving the quality of castings and the development of casting technology, more parts are produced by adopting low-pressure casting, differential pressure casting and pressure-regulating casting, and all belong to anti-gravity casting methods. The basic principle of the casting is that low-pressure gas is used for driving metal melt in a crucible or a heat preservation furnace to rise through a riser tube and enter a mold cavity, and after mold filling is finished, the metal melt in the mold is solidified and fed under the action of pressure.

The traditional aluminum alloy low-pressure, differential-pressure and pressure-regulating wheel casting technology generally adopts a single-sprue single-riser tube mold filling technology. Taking an aluminum alloy wheel as an example, a riser tube is arranged at the center of the wheel, namely the wheel center of the wheel, so that metal melt enters a cavity and is filled and solidified. In order to refine the structure and eliminate the casting defects of shrinkage cavity, shrinkage porosity and the like, the cooling of a wheel mold is generally enhanced in the prior art by adopting water cooling, water mist cooling and the like, however, the enhanced cooling greatly shortens the solidification time of the wheel, for example, the solidification time of the large-size wheel after the enhanced cooling can be shortened to be within 100s, but the problem that the temperature field in the processes of cooling and solidifying the wheel in the production process is difficult to control is caused, so that the sequential solidification is difficult to realize, the product performance is unstable, and the qualification rate is low.

Other filling approaches have been attempted in the prior art for wheels. Patent CN201010107026.8 discloses a bilateral casting technology and device of aluminum alloy wheel low pressure casting sets up the runner in wheel both sides, makes aluminium liquid get into from rim, makes aluminium liquid crystallize to the rim by the wheel center under the mould temperature of quench through to cooling control, has shortened the distance that aluminium liquid flows, and the shrinkage porosity defect at R angle or rim position has been reduced in the cooperation cooling. Documents CN201310557627.2 and CN201410825962.0 disclose that a center gate and two side gates are combined to reduce the weight of the hub and improve the mechanical strength. CN201610390494.8 adopts a quick-witted bimodulus wheel hub mould, and the runner sets up on the rim position equally, realizes once pouring two wheel hubs.

However, the device and the method also have obvious defects, and for the mode that the aluminum liquid only enters from the rim, the inlet is arranged in the middle of the rim, and the aluminum liquid can be shunted after entering, namely the aluminum liquid is filled to the wheel center and the wheel edge at the same time, so that the filling time at each position is uncontrollable, the solidification sequence is uncontrollable, and the defects of shrinkage cavity and shrinkage porosity are easily formed. And for the mode of combining the central gate and the gates at two sides, because the aluminum liquid enters from the two inlets, confluence can be formed at the middle position, and cold shut and the like are easily caused by reasons such as unsmooth gas discharge and the like.

The applicant designs a multi-riser-tube-based rapid sequential solidification wheel forming device and method, wherein a pouring gate of a mold is arranged right below a rim of a wheel or outside an upper R corner of a lower wheel flange. The problem of long-distance feeding after filling is solved by the liquid lifting and filling of a plurality of liquid lifting pipes. However, since the position and shape of the gate are changed, the conventional circular pouring component cannot be used for mold filling any more, and how to realize stable mold filling in this manner becomes a problem to be solved.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problem, the utility model provides a wheel antigravity casting equipment with molten bath heat preservation stove.

The utility model discloses complete technical scheme includes:

a wheel antigravity casting device with a molten pool holding furnace at least comprises a mould, the molten pool holding furnace and a liquid lifting box;

the molten pool heat preservation furnace comprises a furnace body, wherein a heat preservation layer made of refractory materials is arranged on the inner wall of the furnace body, the heat preservation layer surrounds a molten pool, a furnace cover is arranged at the upper part of the furnace body, a central liquid lifting pipe is connected to the central position of the furnace cover, and the molten pool heat preservation furnace is provided with a first electric heating device and a first temperature thermocouple;

the furnace cover is connected with a central liquid lifting pipe, a liquid lifting box is connected above the central liquid lifting pipe, a plurality of shunting channels communicated with the liquid lifting pipe are arranged in a box body of the liquid lifting box, each shunting channel is connected with a shunting sprue, the shunting sprue corresponds to the position right below a wheel mold rim and is communicated with a cavity inlet for pouring a mold cavity, shunted metal melt is poured into the cavity, and a second electric heating device and a second temperature thermocouple are arranged on the liquid lifting box.

The cross section of the flow dividing sprue communicated with the inlet of the cavity is approximately following the shape of the inlet of the cavity at the mold filling position of the casting mold.

The cross section of the flow distribution gate is in the shape that: including first segmental arc and second segmental arc, first segmental arc and second segmental arc are concentric, and the radius and the size of first segmental arc all are less than the second segmental arc, and first segmental arc and second segmental arc both sides are passed through the linkage segment and are connected.

The length of first segmental arc is 72 ~ 76mm, and the length of second segmental arc is 76 ~ 80mm, and the length of both sides linkage segment is 8 ~ 12 mm.

The inner surface of the flow dividing sprue is provided with a screen placing groove for placing a filter screen.

The number of the flow dividing gates is two, and the flow dividing gates are symmetrically arranged on two sides of the axis of the wheel.

The number of the flow dividing gates is more than two and is arranged around the axis of the wheel.

The bottom of the furnace body is provided with rollers which are positioned on the tracks and can move along the tracks.

The furnace cover is also provided with a heat preservation layer below, one side of the furnace cover is provided with a feeding port, the furnace cover is connected with a high-pressure air source, and the upper part of the liquid lifting box is connected with a lower template on the frame.

The method for carrying out the antigravity casting of the wheel according to the equipment comprises the following steps:

(1) liquid lifting: pressurizing the aluminum liquid in the heat preservation furnace by a high-pressure air source, so that the aluminum liquid rises to a liquid lifting box along a central liquid lifting pipe under the pressure and reaches the position of a flow dividing sprue through a flow dividing channel in the liquid lifting box, wherein the pressure rising speed at the stage is 2.8-4.0 KPa/s, and the pressure is increased to 20 KPa;

(2) filling a mold: continuously boosting to enable the aluminum liquid to enter the cavity through the shunt gate, wherein the filling stage is two-stage pressurization, the boosting speed of the first stage is 0.1-0.2 KPa/s, the time is 2-4 s, and then the second stage is started to boost quickly until the cavity is full, and the pressure reaches 35KPa at the moment;

the boosting speed P' in the second stage is determined as follows:

in the formula:

p' is the pressure increasing speed with the unit of kPa/s; h is the total height of the cavity and the unit is mm; rho is the density of the metal melt and has the unit of g/cm³(ii) a K is a resistance coefficient, and the value range of K is 1-1.5; t is preset mold filling time with the unit of s, preferably 10 s; 102 is a unit conversion coefficient; n is the number of the lift tubes, the value range of N is 2-6, the number can be selected according to the number of windows of wheels of different types, and 2-6 is preferred; and x is the liquid raising index of the steel plate, the value range is 0.2-0.8, and in the wheel type scheme adopted in the embodiment, the value is 0.5.

(3) And (3) crystallization, pressurization and pressure maintaining: after the mold filling is finished, the pressure is rapidly increased to 150KPa at the boosting speed of 8-10 KPa/and is maintained for 60-150 s, and the wheel solidification is finished.

(4) Pressure relief and air release: and after the aluminum alloy wheel is solidified, relieving the gas pressure in the molten pool heat-preserving furnace, and enabling the unsolidified aluminum liquid in the liquid lifting box and the central liquid lifting pipe to flow back to the heat-preserving furnace.

The mold temperature prior to ramping is no greater than 400 c, preferably no greater than 350 c, and more preferably no greater than 300 c.

The utility model discloses for prior art's advantage lie in:

the applicant proposes a device and a method for molding a wheel by rapid sequential solidification based on multi-gate edge injection, wherein a gate of a mold is arranged right below a rim of the wheel. By injecting the liquid lifting and mold filling at the edge of the multi-sprue, the mold filling distance of the metal melt is shortened by more than half compared with the existing single liquid lifting pipe mode, the cooling speed and the cooling effect of the wheel are naturally accelerated, and the rapid sequential solidification is realized. Because the position and the shape of the pouring gate are changed, the traditional round pouring component can not be adopted for filling. The utility model discloses a molten bath furnace and liquid case device rise is adapted to the many runners side-pouring mode of runner setting under the rim of wheel, has realized filling the type mode at the stable pouring at wheel edge, and the screen groove is put in the design, can place the filter screen along with the shape, and the inlet channel of internal surface is greater than the runner simultaneously, makes the filter screen can be compacted in the runner below. The mold filling distance of the metal melt is shortened by more than half compared with the existing single lift tube mode by matching with a multi-sprue side pouring mode, the temperature of a metal mold can be reduced to be lower than 320 ℃ from the existing 420 ℃, the cooling speed and the cooling effect of the wheel are naturally accelerated, the rapid sequential solidification is realized, the defect of shrinkage cavity and shrinkage porosity at a heat node is eliminated, the problems that the long-distance feeding effect of the traditional large-size wheel single lift tube technology is poor, and the solidification temperature field is difficult to control after the reinforced cooling are solved, the performance and the production stability of the wheel are obviously improved, the production beat is also shortened, and the production efficiency and the qualification rate of the wheel are improved.

Drawings

FIG. 1 is a schematic structural view of the wheel antigravity casting apparatus with a molten pool holding furnace of the present invention.

Fig. 2 is a cross-sectional view of fig. 1.

Fig. 3 is the distribution schematic diagram of the circular ring surface of the shunt gate under the rim.

Fig. 4 is a schematic view of a wheel according to the prior art.

FIG. 5 shows a portion of the device of FIG. 1 that is susceptible to air entrapment during the filling process.

Fig. 6 is a partially enlarged view of fig. 5.

Fig. 7 is a schematic view of the filling sequence in the slow filling mode in fig. 5.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and the following detailed description.

As shown in fig. 1-2, the wheel antigravity casting apparatus with a molten pool holding furnace of the present invention, which takes low pressure casting as an example, comprises a molten pool holding furnace 1, a mold 2 and a liquid lifting box 3;

the molten pool heat preservation furnace 1 comprises a furnace body 4, a heat preservation layer 5 formed by refractory materials is arranged on the inner wall of the furnace body, the heat preservation layer surrounds a molten pool 6 of metal melt, a furnace cover 7 is arranged on the upper portion of the furnace body, the heat preservation layer is also arranged below the furnace cover, a feeding hole is formed in one side of the furnace cover, a central liquid lifting pipe 8 is connected to the central position of the furnace cover, a high-pressure air source is connected to the furnace cover, a first electric heating device is arranged in the furnace wall; wherein the furnace lid is provided with a charging opening, a high-pressure gas source, a first electric heating device and a thermocouple, which are prior art and are not shown in the figure for the sake of simplifying the drawing. The first electric heating device and the thermocouple are used for measuring the temperature of the metal melt in the molten pool heat-preserving furnace and controlling the temperature to be kept at the mold filling temperature, and the feeding port is used for adding aluminum liquid and a high-pressure air source so as to enable the metal melt to rise into the mold cavity.

The upper part of the central liquid lifting pipe is connected with a liquid lifting box 3, the upper part of the liquid lifting box is connected with a lower template on the rack, a plurality of shunting channels communicated with the liquid lifting pipe are arranged in a box body of the liquid lifting box, each shunting channel is connected with a shunting sprue 9, a plurality of shunting sprues are arranged in the liquid lifting box, the shunting sprues correspond to positions right below a rim of a wheel mold and are communicated with a cavity inlet for pouring into a mold cavity, the shunted metal melt is subjected to blank pressing and pouring into the cavity, and a second electric heating device and a temperature measuring thermocouple are arranged on the liquid lifting box. Wherein the shunt channel, the second electrical heating means and the thermocouple are prior art and are not shown in the figure for the sake of simplicity of the drawing. The second electric heating device and the temperature thermocouple are used for measuring and heating the temperature of the metal melt in the liquid lifting box, so that the metal melt is prevented from freezing.

The mould die cavity entry that every reposition of redundant personnel runner corresponds sets up on the anchor ring 10 under the rim of wheel, the particular explanation, in the utility model discloses in "anchor ring under the rim" indicates the one side relative with the rim on the rim, encircles the anchor ring that wheel central axis formed. The excircle forming the ring is a circle formed by the outline of the outermost ring of the wheel on the surface, and the inner circle is a circle formed by the outline of the outer side of the window area of the wheel around the central axis of the wheel. As shown in fig. 3-4. Correspondingly, the position of the flow dividing sprue communicated with the mold is also arranged at the position.

Particularly preferably, the flow dividing gate and the cavity inlet can be arranged on the annular surface at positions corresponding to the outer sides of the window areas, and can also be arranged on the annular surface at positions corresponding to the connection positions of the rim and the spokes.

In particular, the cross-section of the split sprue in communication with the cavity entrance generally follows the shape of the cavity entrance at the mold filling location of the mold.

Specifically, as shown in fig. 3, the cross-sectional shape of the flow dividing gate 9 is: including first segmental arc 11 and second segmental arc 12, first segmental arc and second segmental arc are concentric, and the radius and the size of first segmental arc all are less than the second segmental arc, and first segmental arc and second segmental arc both sides are passed through linkage segment 13 and are connected.

The inner surface of the flow dividing sprue is provided with a screen placing groove for placing a filter screen, and the shape of the filter screen is matched with the shape of the inlet of the cavity of the casting mold at the mold filling position.

The number of the flow dividing gates is two, and the flow dividing gates are symmetrically arranged on two sides of the axis of the wheel. The number of the flow dividing gates can be more than two and the flow dividing gates are arranged around the axis of the wheel.

The bottom of the furnace body is provided with rollers which are positioned on the tracks and can move along the tracks. This is prior art and is not shown in the figure for simplicity of illustration.

The following explains the wheel low-pressure casting process method matched with the wheel low-pressure casting equipment.

Fig. 4 is a view showing a typical wheel construction in which the central position of the wheel is generally referred to as the center of the wheel, the outer side of the wheel is fitted and fitted with a tire, the portion supporting the tire is referred to as the rim, the portion mounted and connected to the center of the wheel axle, and the portion of the wheel supporting the rim is referred to as the spoke, and a window is left between the spokes in the prior art. The portion of the rim that holds and supports the tire orientation is called the rim.

In the existing production of low-pressure or differential-pressure cast aluminum alloy wheels, a liquid lifting pipe is almost arranged at the center wheel center of the wheel, a melt enters a cavity from a pouring gate at the wheel center through a heat insulation cup and a pouring component connected to the liquid lifting pipe, the melt is divided under the action of a dividing cone, the mold is sequentially filled along the sequence of the wheel center, a spoke, a rim and a rim, and the solidification is realized after the cavity is filled. Meanwhile, the area of the sprue is large, so that the mold filling speed is high. However, some problems caused by the above pouring and filling manner cannot be solved well all the time, for example, the gate distance is long, the filling distance is too long, the hot spot parts such as the connection of the rim and the spoke are very difficult to be fed, shrinkage cavities and shrinkage porosity are easy to form, and the problem that the production in the wheel industry is disturbed is solved. Although the cooling is enhanced by adopting water cooling, water mist cooling and the like to the part to realize sequential solidification, the wheel filling and the solidification time are short, so that the temperature field is difficult to control accurately, and waste products with a certain proportion are still generated inevitably.

In the prior art, a mode of bilateral pouring is adopted in the middle of the side surface of the rim, and the defects of shrinkage cavity and shrinkage porosity are easily formed due to uncontrollable filling and solidification sequences caused by filling and shunting.

Based on this problem, the utility model provides a wheel forming device based on many stalk of liquid that is suitable for with the supporting of aforementioned dysmorphism pouring subassembly, as shown in fig. 1-2, including filling molten bath heat preservation stove, the holding furnace internal connection of molten bath that contains aluminium liquid has high pressurized air source, is equipped with central stalk in the heat preservation stove, and the lower part of this central stalk is soaked in aluminium liquid. When a high-pressure air source is adopted to pressurize the aluminum liquid in the furnace, the aluminum liquid can rise along the central liquid lifting pipe to enter the liquid lifting box, and 2, 4 or other paths of flow distribution are carried out in the liquid lifting box. And enters the cavity of the mold through the cavity inlet through a flow dividing sprue arranged above the liquid lifting box and along with the shape of the cavity inlet.

As mentioned earlier, the cavity entrance sets up on the torus under the rim of wheel, in the utility model discloses in the definition of the torus under "the rim" is as before.

In addition, a thinning device can be arranged above the position of the wheel mold corresponding to the wheel center of the wheel, namely the position of a flow dividing cone corresponding to the traditional center bottom filling mode, and the thinning mechanism can be an ultrasonic thinning mechanism or a vibration thinning mechanism. If the vibration generator and the vibration rod are included, the vibration rod is inserted into the aluminum liquid and vibrates the aluminum liquid in the solidification process, so that dendritic crystals formed by crystallization of the aluminum liquid are broken, nucleation is enhanced, crystal grains are refined, and the mechanical performance of the wheel is improved.

The utility model discloses simultaneously disclose a low pressure casting process that is adapted to under this mode of filling, because the utility model discloses a huge change has been done for prior art to the mode of filling of pouring, and original mode of filling can't be applicable to with solidification technology the utility model discloses, based on this, the utility model discloses a suitable this technology of filling the type position has been designed simultaneously.

The method specifically comprises the following steps:

the boosting speed P' in the second stage is determined as follows:

in the formula:

For the selection of the pressure increasing speed in the liquid lifting stage and the mold filling stage, as the inner diameters of the liquid lifting pipe and the split runner in the liquid lifting box are fixed during liquid lifting, turbulence is basically not generated, the high pressure increasing speed is adopted, so that the molten metal can quickly lift to reach the position of the split runner, and the liquid lifting time is shortened. In the mold filling stage, the complicated shapes of the cavity inlet and the sprue are considered, in the traditional mold filling mode, because a mode of pouring from the position of the wheel center is adopted, the sectional areas of the cavity inlet and the sprue are not large, the sectional area of the cavity at the wheel center is large, turbulence is not easy to generate, and therefore the mold filling and pressure boosting speed can be obtained by experience or experiment. And right the utility model discloses a fill the type mode, adopt to fill the type on the rim ring surface, for irregular shape cavity entry along with, the shape area difference of reposition of redundant personnel passageway and runner is very big, and the space of rim department is less simultaneously, if fill the type pressure unreasonable very easily produce the turbulent flow and roll up gas, cause the gas pocket defect. The mold filling pressure design in the prior art adopts a calculation mode in an ideal state and is corrected by combining a resistance coefficient and the like. The change in the flow state due to the change in the cross-sectional areas of the runner and the gate is not considered. Therefore, the ideal mold-filling boosting speed cannot be obtained by adopting the empirical formula in the prior art.

Therefore, the utility model discloses study the above-mentioned problem, combine to rise the liquid case and water, reposition of redundant personnel runner, die cavity entry top die cavity shape and sectional area to and the flow characteristic of metal melt. It is found that for the wheel rim position, the circular frame position shown by the arrow in fig. 5, there are two positions with obviously changed area in the initial stage of the mold filling, such as the circular frame position shown by the arrow in fig. 6, if turbulent flow is generated, the position is easy to form the gas, through the design and calculation, the utility model discloses a two-stage pressurization, the first stage obviously reduces the pressure-increasing speed, makes the metal melt realize the smooth flow in the initial stage of the mold filling, fills the above-mentioned area to avoid the gas-increasing, as shown in fig. 7 (the arrow is the melt filling direction), then enters the second stage to boost rapidly to shorten the mold filling time. The utility model discloses the second stage fill the type in-process, the research discovery fills type stability and shunts runner quantity and has obvious relation, because traditional mode of pouring is carried out from the wheel center position only has a stalk and runner, consequently can obtain the law and do quantitative processing through the experiment. And the utility model discloses a fill the type mode, reposition of redundant personnel runner quantity can be 2 or more. Under the same pressure-boosting condition, the flow rate at the pouring gate and the flow rate in the square cavity above the cavity inlet can be obviously changed, so that the mold filling flow mode is uncontrollable. Therefore the utility model discloses a research obtains the mode of stepping up of second stage, can see from equation (1), in the same preset fill type time, along with reposition of redundant personnel runner quantity increase, the liquid-lifting speed that it can adopt can progressively increase to can not cause turbulent air entrainment scheduling problem. The resistance coefficient value is related to the viscosity of molten metal, the complexity of a casting cavity and the like, the lower limit is taken when the resistance is small, and the upper limit is taken when the resistance is large.

Example 1:

2 shunting gates are adopted, and the metal melt comprises the following components in percentage by mass: si: 7-9%, Mg: 0.6-0.9%, Zr: 0.01-0.02%, B: 0.005-0.007%, RE: 0.002-0.005%, Nd: 0.002-0.005%, 0-0.15% of Fe, Mn: 0.05-0.1%, Ti: 0.12-0.14%, and the balance of Al and inevitable impurities.

(1) Liquid lifting: pressurizing the aluminum liquid in the heat preservation furnace by a high-pressure air source, so that the aluminum liquid rises to a liquid lifting box along a central liquid lifting pipe under the pressure and reaches the position of a shunting sprue through a shunting channel in the liquid lifting box, wherein the pressure rising speed at the stage is 3.5KPa/s, and the pressure is increased to 20 KPa;

(2) filling a mold: and continuously boosting, so that the molten aluminum enters the cavity through the pouring gate, the boosting speed of the first stage is 0.2KPa/s, the time is 1.8s, the area indicated by an arrow in the figure 6 is stably filled with the molten metal, and then the molten metal enters the second stage and is rapidly filled with the molten metal at the boosting speed of 0.66KPa/s until the cavity is filled.

(3) And (3) crystallization, pressurization and pressure maintaining: after the filling is finished, the pressure is rapidly increased to 150KPa at the boosting speed of 8KPa/s, and the pressure is maintained until the solidification of the wheel is finished. In the pressure maintaining process, the high pressure of the rim hot spot is always kept at the shunting gate for feeding, and the possibility of shrinkage cavity and shrinkage porosity at the position is eliminated under the feeding of high-pressure aluminum liquid. And meanwhile, vibrating and refining the molten metal at the wheel center.

(4) Pressure relief and air release: and after the aluminum alloy wheel is solidified, relieving the gas pressure in the heat preservation furnace, and enabling the unset aluminum liquid in the central liquid lifting pipe and the liquid lifting box to flow back to the heat preservation furnace.

The above, only be the utility model discloses a preferred embodiment, it is not right the utility model discloses do any restriction, all according to the utility model discloses the technical entity all still belongs to any simple modification, change and the equivalent structure change of doing above embodiment the utility model discloses technical scheme's within the scope of protection.

Claims

1. The wheel antigravity casting equipment with the molten pool holding furnace is characterized by at least comprising a mould, the molten pool holding furnace and a liquid lifting box;

the furnace cover is connected with a central liquid lifting pipe, a liquid lifting box is connected above the central liquid lifting pipe, a plurality of shunting channels communicated with the liquid lifting pipe are arranged in a box body of the liquid lifting box, each shunting channel is connected with a shunting sprue, the shunting sprue corresponds to the position right below a wheel mold rim and is communicated with a cavity inlet for pouring into a mold cavity, and shunted metal melt is poured into the mold cavity, and a second electric heating device and a second temperature thermocouple are arranged on the liquid lifting box;

2. The antigravity casting apparatus with a molten bath holding furnace of claim 1, wherein the cross-sectional shape of the flow-dividing gate cross-section is: including first segmental arc and second segmental arc, first segmental arc and second segmental arc are concentric, and the radius and the size of first segmental arc all are less than the second segmental arc, and first segmental arc and second segmental arc both sides are passed through the linkage segment and are connected.

3. The wheel antigravity casting equipment with the molten pool holding furnace of claim 1, wherein the length of the first arc-shaped section is 72-76 mm, the length of the second arc-shaped section is 76-80 mm, and the length of the connecting sections at two sides is 8-12 mm.

4. The vehicle wheel antigravity casting apparatus with a molten pool holding furnace of claim 1, wherein the inner surface of the flow dividing sprue is provided with a screen placing groove for placing a screen.

5. The antigravity casting apparatus with a molten pool holding furnace of claim 1, wherein the number of said distribution gates is two and is symmetrically disposed on both sides with respect to the axis of the wheel.

6. The antigravity casting apparatus with a molten bath holding furnace of claim 1, wherein the number of said split flow gates is greater than two and is disposed around the wheel axis.

7. The vehicle wheel antigravity casting apparatus with a molten pool holding furnace of claim 1, wherein the bottom of the furnace body is provided with rollers which are located on rails and can move along the rails.

8. The wheel antigravity casting equipment with the molten pool holding furnace according to claim 1, wherein the heat preservation layer is also arranged below the furnace cover, a feeding port is formed in one side of the furnace cover, a high-pressure air source is connected to the furnace cover, and the upper portion of the liquid lifting box is connected with the lower template on the rack.