WO2021184977A1

WO2021184977A1 - High vacuum die-casting mold

Info

Publication number: WO2021184977A1
Application number: PCT/CN2021/074282
Authority: WO
Inventors: 曹韩学; 李卫荣; 王程程; 游国强; 陈学民; 龙思远; 徐海章; 朱伟; 孙丽娟
Original assignee: 东莞宜安科技股份有限公司
Priority date: 2020-03-16
Filing date: 2021-01-29
Publication date: 2021-09-23
Also published as: CN111266550A

Abstract

A high vacuum die-casting mold (100), comprising a pressure chamber cavity (10), a spray head (20), a vacuum valve (60), a vacuum channel (70), a piston rod (80), a vacuum pump (91), a connecting pipe (92), a die-casting fixed mold (30) and a die-casting movable mold (40) cooperating with the die-casting fixed mold for mold opening and closing. A forming cavity (50) is formed by the die-casting movable mold together with the die-casting fixed mold in an enclosed manner during mold closing, the pressure chamber cavity penetrates through the die-casting fixed mold and is provided with a pressure chamber channel (11) and a pouring port (12), the pouring port is located on a side wall of the pressure chamber channel, and the spray head is slidably fitted in the pressure chamber channel; the vacuum channel is provided at the die-casting movable mold, a first end thereof is in communication with the forming cavity, and a second end is in communication with a first end of the connecting pipe, a second end of the connecting pipe sequentially assembles the vacuum valve and the vacuum pump in series, and the piston rod penetrates through the die-casting movable mold and selectively opens or closes the first end of the vacuum channel. The high vacuum die-casting mold can rapidly achieve vacuumizing of the forming cavity, has a good vacuumizing effect, greatly improves the internal quality of a product, and allows for heat treatment of a casting.

Description

High vacuum die casting mold

Technical field

The invention relates to a vacuum die-casting technology, in particular to a high-vacuum die-casting mold.

Background technique

Since the traditional die-casting process does not vacuum the molding cavity, the gas in the molding cavity has a great influence on the quality of the product, which is mainly manifested in two aspects: (1) Formation of gas resistance-gas and melt oxidation, and filling and melting The body flow is partially solidified, and the back pressure introduces flow marks, dissatisfaction, cold separation, entrainment and other die casting process defects, which reduces the process yield of large, complex, and thin-walled die castings; (2) The introduction of internal air causes defects-jetting Filling causes gas to mix into the filling melt flow, and introduces process defects such as pores, gas shrinkage holes, and gas slag holes in the casting. In addition, the high temperature desolvation of the gas makes the castings unable to be modified by heat treatment, which reduces the density, dynamic and static mechanical properties and adjustment possibilities of the castings.

The vacuum die-casting method removes the gas in the molding cavity of the die-casting mold during the die-casting process, thereby eliminating or significantly reducing the pores and dissolved gases in the die-casting part, thereby improving the mechanical properties and surface quality of the die-casting part.

At present, the types of vacuum methods currently applied to die-casting molds are as follows:

(1) Actively disconnect the vacuum valve in advance

The method of disconnecting the vacuum is: using the hydraulic or pneumatic action controlled by the time timer or the travel switch to realize the early closing of the vacuum valve;

The shut-off mechanism of the vacuum channel is: the filled melt flow is rapidly solidified under the chill of the exhaust channel, and the melt flow is terminated;

Dynamic characteristics of vacuuming: The vacuuming speed is restricted by the narrow and long vacuuming channel at the end of the cavity, and the vacuum degree of the cavity is increased at a low speed.

(2) "Z" type exhaust channel method

The method of disconnecting the vacuum is: using the chilling effect of the wide and thin "Z"-shaped exhaust channel to rapidly solidify the melt flow and realize the automatic closing of the vacuum channel;

The shut-off mechanism of the vacuum channel: the filled melt flow is solidified under the chilling action of the exhaust channel, and the melt flow is terminated;

Vacuum pumping dynamics: the pumping speed is restricted by the wide and thin, constantly changing direction of the "Z"-shaped pumping channel, and the vacuum degree of the cavity is increased at a very low speed.

(3) Double core mechanical vacuum valve

Disconnect the vacuum method: the high-speed filling melt flow pushes the "start spool", drives the linkage "exhaust spool", and closes the exhaust channel;

Vacuum channel shut-off mechanism: use the momentum when the high-speed filling melt flow reaches the "start spool" to activate the "exhaust spool" action to close the exhaust channel;

Dynamic characteristics of vacuum pumping: The vacuum pumping speed is restricted by the tortuous vacuum channel, and the vacuum pumping speed of the cavity is higher.

(4) Double piston mechanical linkage vacuum valve

Disconnect the vacuum method: the high-speed filling melt flow triggers the "active piston" and drives the linkage "slave piston" to close the exhaust channel;

Vacuum channel shut-off mechanism: use the momentum when the high-speed filling melt flow contacts the "active piston" to push the "slave piston" action to close the exhaust channel;

Vacuum pumping dynamics: the pumping speed is improved, but the pumping channel is still narrow and tortuous, and the vacuum pumping speed of the cavity is still not ideal.

Therefore, there is an urgent need for a high-vacuum die-casting mold that can quickly vacuumize the molding cavity and has a good vacuuming effect to greatly improve the internal quality of the product and the casting can be heat-treated to overcome the above-mentioned defects.

Summary of the invention

The purpose of the present invention is to provide a high-vacuum die-casting mold which can quickly realize vacuuming of the molding cavity and has a good vacuuming effect to greatly improve the internal quality of the product and the casting can be heat treated.

In order to achieve the above purpose, the high vacuum die-casting mold of the present invention includes a pressure chamber cavity, a shooting head, a vacuum valve, a vacuum channel, a piston rod, a vacuum pump, a connecting pipe, a fixed die-casting mold, and a die-casting fixed mold for opening and closing the mold. Die-casting movable mold. The movable die-casting mold and the fixed die-casting mold enclose a molding cavity together when the die-casting die is closed, and the pressure chamber cavity is inserted into the fixed die-casting mold and is provided with a pressure chamber channel communicating with the molding cavity and The pouring port communicated with the pressure chamber passage, the pouring port is located on the side wall of the pressure chamber passage, and the shooting head is slidably sleeved in the pressure chamber passage and is used to remove the material from the pressure chamber. The material that enters the pressure chamber channel is automatically pushed into the molding cavity; the vacuum channel is opened at the die-casting movable mold, and the first end of the vacuum channel communicates with the molding cavity, so The second end of the vacuum channel communicates with the first end of the connecting pipe, and the second end of the connecting pipe sequentially connects the vacuum valve and the vacuum pump in series, and the piston rod is movably inserted into the die casting The movable mold selectively opens or closes the communication between the first end of the vacuum channel and the molding cavity.

Preferably, the high-vacuum die-casting mold of the present invention further includes a negative pressure tank installed at a position of the connecting pipe between the vacuum valve and the vacuum pump.

Preferably, the pressure chamber passage extends parallel to the clamping direction of the high vacuum die-casting mold to the die-casting movable mold, and the vacuum passage extends to the clamping direction perpendicular to the high-vacuum die-casting mold. The outer wall surface of the die-casting movable mold.

Preferably, the pressure chamber channel is located on one side of the molding cavity, and the vacuum channel is located on the opposite side of the molding cavity.

Preferably, the pressure chamber channel and the molding cavity are connected with a direction perpendicular to the clamping direction of the high vacuum die-casting mold, which is enclosed by the fixed die-casting mold and the movable die-casting mold when the mold is closed. Layout of the connection gap.

Preferably, the vacuum channel is offset backward with respect to the molding cavity and is displaced back and forth from the molding cavity.

Preferably, the piston rod is slidably inserted into the die-casting movable mold in a direction parallel to the clamping direction of the high-vacuum die-casting mold, and the piston rod blocks or opens the first part of the vacuum channel from the side. end.

Preferably, the injection head is slidably inserted into the pressure chamber channel in a direction parallel to the clamping direction of the high vacuum die-casting mold.

Compared with the prior art, because the high vacuum die-casting mold of the present invention further includes a vacuum valve, a vacuum channel, a piston rod, a vacuum pump, and a connecting pipe, the vacuum channel is opened at the die-casting movable mold, and the first end of the vacuum channel is connected to the molding cavity The second end of the vacuum channel communicates with the first end of the connecting pipe. The second end of the connecting pipe connects the vacuum valve and the vacuum pump in series. The piston rod is movably inserted into the die-casting movable mold and selectively opened or closed. The communication between the first end of the vacuum channel and the molding cavity; therefore, during vacuuming, the piston rod moves to open the communication between the first end of the vacuum channel and the molding cavity. Then, the vacuum pump works under the cooperation of the vacuum valve. The molding cavity is evacuated through the connecting pipe and the vacuum channel, and the nozzle automatically pushes the material entering the pressure chamber channel into the molding cavity; when the vacuum is completed, the piston rod closes the first end of the vacuum channel and The communication between the molding cavities to ensure the molding quality of the product. Therefore, the high-vacuum die-casting mold of the present invention can quickly achieve vacuuming of the molding cavity, and the vacuuming effect is good to greatly improve the internal quality of the product and the casting can be heat treated. In addition, the vacuum structure composed of a vacuum channel, a piston rod, a vacuum valve, a connecting pipe and a vacuum pump has the advantage of a simple structure.

Description of the drawings

Fig. 1 is a schematic diagram of the internal structure of the high vacuum die-casting mold of the present invention when the first end of the piston rod opens the vacuum channel and the molding cavity is connected and vacuum is performed.

2 is a schematic diagram of the internal structure of the high-vacuum die-casting mold of the present invention when the first end of the piston rod closes the vacuum channel and the molding cavity is connected without vacuum.

Detailed ways

In order to describe the technical content and structural features of the present invention in detail, the following further descriptions will be made in conjunction with the embodiments and the accompanying drawings.

1 and 2, the high-vacuum die-casting mold 100 of the present invention includes a pressure chamber cavity 10, a shooting head 20, a vacuum valve 60, a vacuum channel 70, a piston rod 80, a vacuum pump 91, a connecting pipe 92, and a die-casting fixed mold 30 And the die-casting movable mold 40 which is matched with the die-casting fixed mold 30 to open and close the mold. The movable die-casting die 40 and the fixed die-casting die 30 enclose a molding cavity 50 when the die-casting die 40 is closed. The state is shown in Figs. 1 and 2; The pressure chamber cavity 10 is supported and fixed; the pressure chamber cavity 10 is provided with a pressure chamber passage 11 communicating with the molding cavity 50 and a discharge port 12 communicating with the pressure chamber passage 11, and the discharge port 12 is located on the side of the pressure chamber passage 11 On the wall, proceed from the side to the pressure chamber passage 11. The shooting head 20 is slidably fitted in the pressure chamber passage 11, so that the shooting head 20 can freely slide in the pressure chamber passage 11, and the shooting head 20 is used to automatically transfer the material entering the pressure chamber passage 11 from the pouring port 12 To ensure that the molding cavity 50 needs materials when molding products. Since the injection head 20 needs to slide in the pressure chamber channel 11 and is used to push the material into the molding cavity 50, the injection head 20 and the pressure chamber passage 11 are clearance fits. The vacuum channel 70 is opened at the movable die 40, the first end of the vacuum channel 70 communicates with the molding cavity 50, the second end of the vacuum channel 70 communicates with the first end of the connecting pipe 92, and the second end of the connecting pipe 92 is in turn The vacuum valve 60 and the vacuum pump 91 are connected in series, so that the gas entering the vacuum channel 70 first flows through the vacuum valve 60 and then flows into the vacuum pump 91. The piston rod 80 movably penetrates the movable die 40 and selectively opens the communication between the first end of the vacuum channel 70 and the molding cavity 50, as shown in Fig. 1, or closes the first end of the vacuum channel 70 and The state of the communication between the molding cavities 50 is shown in FIG. 2. Specifically, in order to improve the vacuuming effect, the high-vacuum die-casting mold 100 of the present invention further includes a negative pressure tank 93 installed at a position of the connecting pipe 92 between the vacuum valve 60 and the vacuum pump 91. More specifically, as follows:

As shown in Figures 1 and 2, the pressure chamber passage 11 extends parallel to the clamping direction of the high-vacuum die-casting mold 100 (that is, the direction indicated by the arrow A) to the die-casting movable mold 40, and the vacuum passage 70 extends along the direction perpendicular to the high-vacuum die-casting mold. The clamping direction of the mold 100 (shown by arrow B) extends to the outer wall surface 41 of the die-casting movable mold 40. Preferably, the pressure chamber channel 11 is located on one side of the molding cavity 50, such as but not limited to as shown in the drawings On the lower side, the vacuum channel 70 is located on the opposite side of the molding cavity 50, such as but not limited to the upper side shown in the drawings. This design can further improve the vacuuming speed and efficiency of the molding cavity 50. Specifically, the pressure chamber passage 11 and the molding cavity 50 are connected with a connection gap that is enclosed by the fixed die-casting mold 30 and the movable die-casting mold 40 when the molds are closed, and is arranged along the direction perpendicular to the clamping direction of the high-vacuum die-casting mold 100. 94. The vacuum channel 70 is offset backwards relative to the molding cavity 50 and is misaligned with the molding cavity 50 back and forth. This design allows the pressure chamber channel 11 to enter the molding cavity 50 through the connection gap 94, and then is drawn away by the vacuum channel 70, that is In other words, the vacuum channel 70 sucks all the gas that enters the molding cavity 50, so the vacuum effect is good; at the same time, this design can also ensure that the piston rod 80 can reliably open or close the first end of the vacuum channel 70 and the molding cavity 50 Connectivity between. More specifically, the piston rod 80 is slidably inserted into the die-casting movable mold 40 in a direction parallel to the clamping direction of the high-vacuum die-casting mold 100, and the piston rod 80 is supported by the movable die-casting mold 40, and the piston rod 80 is laterally ( For example, but not limited to the upper side shown in the drawings) the first end of the vacuum channel 70 is blocked or opened; in addition, the shooting head 20 is slidably inserted into the pressure chamber channel 11 along the clamping direction parallel to the high vacuum die-casting mold 100 , So that the shooting head 20 can automatically push the material into the molding cavity 50, but it is not limited to this.

Compared with the prior art, because the high-vacuum die-casting mold 100 of the present invention further includes a vacuum valve 60, a vacuum channel 70, a piston rod 80, a vacuum pump 91 and a connecting pipe 92, the vacuum channel 70 is opened at the die-casting movable mold 40, and the vacuum channel The first end of 70 communicates with the molding cavity 50, the second end of the vacuum channel 70 communicates with the first end of the connecting pipe 92, and the second end of the connecting pipe 92 connects the vacuum valve 60 and the vacuum pump 91 in series, and the piston rod 80 is movably placed in the die-casting movable mold 40 and selectively opens or closes the communication between the first end of the vacuum channel 70 and the molding cavity 50; therefore, as shown in FIG. 1, when the vacuum is pumped, the piston rod 80 Moves to open the communication between the first end of the vacuum channel 70 and the molding cavity 50. Then, the vacuum pump 91 vacuumizes the molding cavity 50 through the connecting pipe 92 and the vacuum channel 70 under the cooperation of the vacuum valve 60. The gas flow direction is as shown in As shown by the arrow in Fig. 1, the shooting head 20 automatically pushes the material entering the pressure chamber passage 11 into the molding cavity 50; as shown in Fig. 2, when the vacuum is completed, the vacuum passage 70 is closed by the piston rod 80 The first end is connected to the molding cavity 50 to ensure the molding quality of the product. Therefore, the high-vacuum die-casting mold 100 of the present invention can quickly achieve vacuuming of the molding cavity, and the vacuuming effect is good to greatly improve the internal quality of the product and the casting can be heat treated. In addition, the vacuum structure composed of the vacuum channel 70, the piston rod 80, the vacuum valve 60, the connecting pipe 92 and the vacuum pump 91 has the advantage of a simple structure.

The above-disclosed are only preferred examples of the present invention, which of course cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the claims of the present invention still fall within the scope of the present invention.

Claims

A high-vacuum die-casting mold includes a pressure chamber cavity, a shooting head, a fixed die-casting die, and a movable die-casting die cooperating with the fixed die-casting die for opening and closing. The movable die-casting die is fixed with the die when the die is closed. The molds jointly enclose a molding cavity, and the pressure chamber cavity is inserted into the fixed die-casting mold and is provided with a pressure chamber channel communicating with the molding cavity and a pouring port communicating with the pressure chamber channel. The pouring port is located on the side wall of the pressure chamber passage, and the shooting head is slidably fitted in the pressure chamber passage and is used to automatically push the material that enters the pressure chamber passage from the pouring port to In the molding cavity, it is characterized in that the high vacuum die-casting mold further includes a vacuum valve, a vacuum channel, a piston rod, a vacuum pump, and a connecting pipe, the vacuum channel is opened at the die-casting movable mold, and the vacuum channel The first end communicates with the molding cavity, the second end of the vacuum channel communicates with the first end of the connecting pipe, and the second end of the connecting pipe connects the vacuum valve and the vacuum pump in series, The piston rod is movably inserted into the die-casting movable mold and selectively opens or closes the communication between the first end of the vacuum channel and the molding cavity.
The high-vacuum die-casting mold according to claim 1, further comprising a negative pressure tank installed at a position of the connecting pipe between the vacuum valve and the vacuum pump.
The high-vacuum die-casting mold according to claim 1, wherein the pressure chamber passage extends parallel to the clamping direction along the high-vacuum die-casting mold to the movable die-casting mold, and the vacuum passage extends perpendicularly to the die-casting movable mold. The clamping direction of the high-vacuum die-casting mold extends to the outer wall surface of the die-casting movable mold.
The high vacuum die casting mold according to claim 3, wherein the pressure chamber channel is located on one side of the molding cavity, and the vacuum channel is located on the opposite side of the molding cavity.
The high-vacuum die-casting mold according to claim 4, characterized in that, between the pressure chamber channel and the molding cavity is connected an edge surrounded by the fixed die-casting mold and the movable die-casting mold when the mold is closed. A connection gap arranged perpendicular to the clamping direction of the high vacuum die-casting mold.
The high-vacuum die-casting mold according to claim 4, wherein the vacuum channel is offset backward with respect to the molding cavity and is displaced back and forth from the molding cavity.
The high-vacuum die-casting mold according to claim 1, wherein the piston rod is slidably inserted into the movable die-casting mold in a direction parallel to the clamping direction of the high-vacuum die-casting mold, and the piston rod is moved from The first end of the vacuum channel is blocked or opened laterally.
The high vacuum die-casting mold according to claim 1, wherein the shooting head is slidably inserted into the pressure chamber channel along a mold clamping direction parallel to the high-vacuum die-casting mold.