A die casting mold and die casting method under integrated double-shot die casting

Abstract

The present invention relates to a die-casting mold and a die-casting method under integrated double-shot die-casting, which belongs to the field of die-casting technology. The die-casting mold comprises a template and a mold cavity in the template. The template is provided with two injection assemblies, and the two injection assemblies are respectively used to press molten metal into the mold cavity; any one of the injection assemblies is provided with a pressure sensor, and the pressure sensor is used to detect the pressure of the molten metal in the injection assembly. The two pressure sensors are electrically connected to a control module, and the two pressure sensors upload pressure data to the control module. The control module is pre-input with a pressure difference threshold, and the control module determines whether the difference between the two pressure data is greater than the pressure difference threshold. When the judgment result is yes, the control module issues an alarm.

Description

Technical Field

[0001] The invention belongs to the technical field of die casting, and in particular relates to a die casting mold and a die casting method under integrated double-shot die casting. Background Art

[0002] Die casting is a commonly used metal processing method that forms various metal products by injecting molten metal into a pre-designed mold and cooling and solidifying it under a certain pressure. Die casting technology is widely used in the manufacture of various parts and products, including automotive parts, home appliances, industrial equipment, etc.

[0003] In general die-casting schemes, a single-shot system is usually used, that is, there is only one punch, and the molten metal enters the cavity through a single runner. This type of system has a simple structure. However, when the cavity is large, the punch of the single-shot system is far away from the boundary of the cavity, resulting in a long filling distance and a large pressure loss, which makes it impossible to complete the die-casting well. For this reason, people have invented a double-shot die-casting system, that is, metal is pressed into the cavity from two runners through two pressure sources, so that the molten metal can fill the larger cavity more quickly. For example, Chinese patent CN108672673A discloses a double-punch injection structure of a die-casting machine, including a mold frame, a mold core, and a gate sleeve, the mold core is fixedly positioned in the mold frame, the gate sleeve is embedded in the mold core, the number of the gate sleeves is multiple, and the mold frame is connected to a plurality of pressure chambers that are connected to the gate sleeves one by one, and each pressure chamber is provided with an axially movable punch rod. The beneficial effects of the present invention include: by setting two punches, the flow time of the molten metal in the cavity is greatly shortened, multi-point pressurization and shrinkage compensation can be achieved, and the product quality is improved; however, in the above scheme, in some cases, the two punches may not be able to operate synchronously due to random errors. When such a situation occurs, the quality of the finished product will be reduced, and the above structure does not make improvements to address such situations. Therefore, a die-casting mold and die-casting method for integrated double-shot die-casting with high punch movement synchronization and good die-casting effect are needed. Summary of the invention

[0004] In order to solve the above problems existing in the prior art, the present invention provides a die-casting mold and a die-casting method under integrated double-shot die-casting, which has the characteristics of high synchronization of punch movement and good die-casting effect.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A die-casting mold and die-casting method under integrated double-shot die-casting, comprising a template and a die cavity in the template, wherein the template is provided with two shot assemblies, and the two shot assemblies are respectively used to press molten metal into the die cavity;

[0007] Any of the injection components is provided with a pressure sensor, which is used to detect the pressure of the molten metal in the injection component. The two pressure sensors are electrically connected to a control module, and the two pressure sensors upload pressure data to the control module. The control module is pre-input with a pressure difference threshold. The control module determines whether the difference between the two pressure data is greater than the pressure difference threshold. When the judgment result is yes, the control module issues an alarm.

[0008] As a preferred technical solution of the present invention, the control module is electrically connected to the two injection components respectively, and the two injection components are arranged in a one-to-one correspondence with the two pressure sensors. When the pressure data exceeds the standard value, the control module reduces the injection power of the injection component corresponding to the pressure data, and when the pressure data is lower than the standard value, the control module increases the injection power of the injection component corresponding to the pressure data.

[0009] As a preferred technical solution of the present invention, the control module is pre-input with a pressure standard value p0 and a standard injection power Y0, and the two pressure sensors upload the pressure data p1 and p2 to the control module, and the control module adjusts the injection power of the injection assembly to Y1 and Y2 according to p1, p2 and p0 respectively;

[0010] Among them, Y1=p0 / p1×Y0, Y2=p0 / p2×Y0.

[0011] As a preferred technical solution of the present invention, a temperature sensor array is arranged in the template, and the temperature sensor array is electrically connected to the control module. The temperature sensor array is used to detect the peak temperature position in the mold cavity and upload the peak position to the control module, and the control module increases the power of the injection component closest to the peak position.

[0012] As a preferred technical solution of the present invention, the control module is pre-input with the standard position c0 and the distance c1 between the two injection assemblies, the temperature sensor array is used to detect the peak temperature position in the mold cavity and upload the peak position to the control module, the control module calculates the distance c between the peak temperature position and the standard position, and calculates A1 based on c, and the control module increases the power of the injection assembly closest to the peak position by A1 times;

[0013] Where A1=c / c0 / 2+1

[0014] As a preferred technical solution of the present invention, the control module is electrically connected to a control panel, and the control panel is used to input the values ​​of c0 and p0.

[0015] The present invention also provides a die-casting method under integrated double-shot die-casting, which is applicable to the above-mentioned die-casting mold under integrated double-shot die-casting, and comprises the following steps:

[0016] Step 1: Two injection assemblies press the molten metal into the mold cavity respectively;

[0017] Step 2: Two pressure sensors respectively detect the pressure of the molten metal in the two injection assemblies, and upload the pressure data to the control module;

[0018] Step 3: The control module determines whether the difference between the two pressure data is greater than the pressure difference threshold. When the judgment result is yes, the control module issues an alarm.

[0019] The beneficial effects of the present invention are:

[0020] (1) By setting up pressure sensors to detect the molten metal pressure in the two shot assemblies respectively, and judging the difference between the two detection results to judge the synchronization of the two shot assemblies, the two shot assemblies are operated synchronously to give the molten metal the same pressure, so that the molten metal maintains normal operation when the pressure given to the two pressure sensors is consistent. When the synchronization of the two shot assemblies is poor and the pressure difference detected by the two pressure sensors is large, an alarm is issued to remind the operator to handle it;

[0021] (2) by setting the control module to reduce the injection power of the injection assembly corresponding to the pressure data when the pressure data exceeds the standard value according to the comparison result of the pressure data, and to increase the injection power of the injection assembly corresponding to the pressure data when the pressure data is lower than the standard value, the synchronization of the two injection assemblies is improved according to the working conditions of the injection assemblies;

[0022] (3) By enabling the control module to detect the degree of deviation of the metal jets ejected by the two injection assemblies in the double injection system according to the temperature sensor, and then correcting the injection power of the injection assembly according to the degree of deviation, the coincidence degree between the intersection point of the two metal jets and the center of the mold cavity is improved, thereby improving the consistency of the physical properties of various surfaces after metal forming. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0024] Figure 1 It is a structural schematic diagram of the present invention;

[0025] Figure 2 This is a control loop block diagram of the present invention.

[0026] Description of main component symbols:

[0027] In the figure: 1. template; 11. mold cavity; 2. injection assembly; 21. injection rod; 3. control module. DETAILED DESCRIPTION

[0028] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0029] See also Figure 1-2 , a die-casting mold and die-casting method under integrated double-shot die-casting, including a template 1 and a mold cavity 11 in the template 1, specifically, the template 1 includes a movable template 1 and a fixed template 1, when the movable template 1 is close to and fits with the fixed template 1 under a driving component, the movable template 1 and the fixed template 1 are combined to form a cavity, and at the same time, the template 1 is connected to the cavity with two runners, and the ends of the two runners away from the cavity are connected to the injection assembly 2, and the injection assembly 2 includes at least one barrel for holding molten metal, and a shot rod 21 for pressing the molten metal in the barrel into the runner. In this embodiment, the shot rod 21 is driven by a screw structure, and the driving source of the screw structure is a motor. At this time, the mold cavity 11 is connected to the two injection assemblies 2 through the two runners, and the distances between the two die-casting assemblies and the geometric center of the mold cavity 11 are equal;

[0030] When in use, the injection rod 21 of the injection assembly 2 moves toward the runner under the drive of the lead screw structure, and presses the molten metal in the barrel into the mold cavity along the runner to complete the double-injection die-casting.

[0031] During the use of the above structure, the two injection rods 21 may fail to operate synchronously due to random errors. When such a situation occurs, the pressure of the molten metal flow pressed into the cavity in the two injection components 2 will be inconsistent. Since the physical parameters of the metal part in the mold cavity 11 are related to the pressure of the molten metal during die casting, the asynchronous operation of the two injection rods 21 will lead to inconsistent physical parameters of the two parts of the metal part after molding, and the quality of the finished product will be reduced. To avoid such a situation, a pressure sensor is provided in any injection component 2. In this embodiment, each pressure sensor is respectively provided on the inner wall of the barrel of the corresponding injection component 2. The pressure sensor is used to detect the pressure of the molten metal in the injection component 2. At the same time, it also includes a control module 3. The two pressure sensors are respectively electrically connected to the control module 3. The two pressure sensors detect pressure data in real time and upload the detected pressure data to the control module 3 at a frequency of once per millisecond. The control module 3 is pre-input with a pressure difference threshold.

[0032] When in use, the injection rod 21 of the injection assembly 2 presses the molten metal into the mold cavity, and the molten metal is subjected to pressure, and the pressure is transmitted to the pressure sensor on the inner wall of the barrel. Each time the control module 3 receives data uploaded by the two pressure sensors, it first calculates the difference between the two pressure data. Each time the control module 3 calculates the pressure difference, it determines whether the pressure difference is greater than the pressure difference threshold;

[0033] When the two injection assemblies 2 are running synchronously, the pressure applied to the molten metal by the injection rods 21 of the two injection assemblies 2 is consistent, and the pressure data detected by the two pressure sensors and uploaded to the control module 3 are consistent. At this time, the pressure difference calculated by the control module 3 is small, and the control module 3 determines that the pressure difference does not exceed the pressure difference threshold, and completes the maintenance of normal operation when the injection rods 21 are running synchronously;

[0034] When the judgment result is no, it means that the pressure given to the pressure sensor by the molten metal is inconsistent, that is, the pressure given to the molten metal by the injection rods 21 of the two injection assemblies 2 is inconsistent, and the operation synchronization of the two injection rods 21 is low. At this time, the control module 3 issues an alarm to complete the early warning when the synchronization of the two injection assemblies 2 is low;

[0035] By setting up pressure sensors to detect the molten metal pressure in the two shot assemblies 2 respectively, and judging the difference between the two detection results to judge the synchronization of the two shot assemblies 2, the two shot assemblies 2 can be operated synchronously to give the molten metal the same pressure, so that the molten metal can maintain normal operation when the pressure given to the two pressure sensors is consistent. When the synchronization of the two shot assemblies 2 is poor and the pressure difference detected by the two pressure sensors is large, an alarm is issued to remind the operator to handle it.

[0036] In the above structure, the control module 3 is only provided with an early warning when the synchronization of the two injection assemblies 2 is poor, and the synchronization is not improved according to the working condition of the injection assembly 2 in this case. For this reason, the control module 3 is electrically connected to the two injection assemblies 2 respectively, and the two injection assemblies 2 are provided with two pressure sensors in a one-to-one correspondence. Specifically, the driving motor of the screw structure is also electrically connected to the control module 3, and the control module 3 controls the screw structure by controlling the electrical signal of the motor. At the same time, the control module 3 records the pressure sensor and the injection rod 21 in the same injection assembly 2 as a group. At this time, the pressure sensor in the barrel of a certain injection assembly 2 is provided in correspondence with the injection rod 21 in the same injection assembly 2.

[0037] Specifically, after receiving the pressure data uploaded by the two pressure sensors each time, the control module 3 first compares the two pressure data with the standard values ​​respectively. When it is determined through the comparison that a certain pressure data exceeds the standard value, it means that the injection rod 21 of the injection assembly 2 where the pressure sensor uploading the pressure data is located is running too fast, and the operating power of the corresponding injection assembly 2 needs to be reduced. At this time, the control module 3 instructs the injection assembly 2 where the pressure sensor uploading the pressure data is located to reduce the injection power;

[0038] Similarly, when it is determined through comparison that a certain pressure data is lower than the standard value, it means that the injection rod 21 of the injection assembly 2 where the pressure sensor uploading the pressure data is located is running too slowly, and the operating power of the corresponding injection assembly 2 needs to be increased. At this time, the control module 3 instructs the injection assembly 2 where the pressure sensor uploading the pressure data is located to increase the injection power;

[0039] In the above process, specifically, the control module 3 is pre-input with the pressure standard value p0 and the standard injection power Y0, and the two pressure sensors upload the pressure data p1 and p2 to the control module 3, and the control module 3 adjusts the injection power of the injection assembly 2 to Y1 and Y2 according to p1, p2 and p0 respectively; wherein Y1 = p0 / p1×Y0, Y2 = p0 / p2×Y0;

[0040] The pressure sensor for uploading p1 is arranged in the injection assembly 2 running at Y1, and the pressure sensor for uploading p2 is arranged in the injection assembly 2 running at Y2;

[0041] When p1 is lower and less than p0 at a certain time point, that is, the pressure data is lower than the standard value, it means that the injection rod 21 of the injection assembly 2 where the pressure sensor uploading the pressure data is located is running too slowly, and the injection power of the injection assembly 2 needs to be increased. At this time, the value of p0 / p1 is greater than 1, and the value of Y1=p0 / p1×Y0 is increased. When the control module 3 instructs the injection assembly 2 to operate at the Y1 power, the power of the injection assembly 2 is increased when the molten metal injection pressure is low; similarly, when p1 is lower and greater than p0 at a certain time point, that is, the pressure data is lower than the standard value, it means that the injection rod 21 of the injection assembly 2 where the pressure sensor uploading the pressure data is located is running too fast, and the injection power of the injection assembly 2 needs to be reduced. At this time, the value of p0 / p1 is less than 1, and the value of Y1=p0 / p1×Y0 is reduced. When the control module 3 instructs the injection assembly 2 to operate at the Y1 power, the power of the injection assembly 2 is reduced when the molten metal injection pressure is high;

[0042] Through the above method, another injection assembly 2 running at power Y2 can also be adjusted according to pressure data p2;

[0043] By setting the control module 3 according to the comparison result of the pressure data, when the pressure data exceeds the standard value, the injection power of the injection component 2 corresponding to the pressure data is reduced, and when the pressure data is lower than the standard value, the injection power of the injection component 2 corresponding to the pressure data is increased, thereby improving the synchronization of the two injection components 2 according to the working conditions of the injection components 2.

[0044] In the above process, in some cases, due to the randomness of the jet movement of the molten metal in the die casting, the two metal jets entering the cavity from the two injection assemblies 2 may not meet at the center of the cavity. At this time, the pressure center of the molten metal in the cavity deviates from the geometric center, which may cause a large pressure difference after the metal jet fills the edge of the cavity, resulting in inconsistent surface physical parameters of the metal parts after molding. In order to reduce the occurrence of such a situation, the convergence point of the metal jet is corrected to the center of the cavity. A temperature sensor array is provided in the template 1, and the temperature sensor array is electrically connected to the control module 3. The temperature sensor array is used to detect the peak temperature position in the cavity 11 and upload the peak position to the control module 3. The control module 3 increases the power of the injection assembly 2 closest to the peak position;

[0045] Specifically, the temperature sensor array is a plurality of temperature sensors arranged on the inner wall of the template 1 body, each temperature sensor is electrically connected to the control module 3, each temperature sensor is used to detect the temperature around its own position and upload it to the control module 3, the setting position of the temperature sensor is parallel to the bottom surface of the template 1, and at the same time, the control module 3 is pre-input with the coordinate system of the plane where the temperature sensor array is located, and the coordinate system is marked with the coordinate position of each temperature sensor on the plane, as well as the position of the two die-casting components on this plane coordinate system;

[0046] After the two molten metal jets converge at a certain point in the mold cavity, the pressure of the molten metal at the convergence point is further increased under the action of mutual squeezing, and the temperature is further increased under the action of pressure. Therefore, when a convergence point appears in the mold cavity 11 during a die-casting operation, the temperature data detected by the temperature sensor array around the convergence point is relatively high. The control module 3 determines the highest one of the temperature data by comparison, which is recorded as the peak data. Then the control module 3 finds the position of the temperature sensor that uploads the highest temperature data on the plane coordinate system, which is recorded as the peak position. The control module 3 calculates the distance between the peak position and the two die-casting components on the plane coordinate system. When one of the distances is smaller, it means that the peak position and the intersection are closer to a certain die-casting component. At this time, the pressure of this die-casting component needs to be increased, which will make the pressure of the two molten metal jets move away from this die-casting component, and then closer to the geometric center of the mold cavity 11, thereby reducing the probability of inconsistent physical parameters at various locations on the surface of the molded metal part.

[0047] Specifically, the control module 3 is pre-input with the coordinate c0 of the standard position on the plane coordinate system and the distance c1 between the two injection assemblies 2 on the plane coordinate system. The temperature sensor array is used to detect the peak temperature position in the mold cavity 11 and upload the peak position to the control module 3. After the control module 3 calculates the peak temperature, it calculates the distance c between the peak position and the standard position, and calculates A1 based on c. Then, the control module 3 increases the power of the injection assembly 2 closest to the peak position by A1 times, where A1=c / c0 / 2+1;

[0048] When c is large, it means that the peak position is far from the geometric center of the mold cavity 11, and it is necessary to significantly increase the power of the injection component 2 closest to the peak position to make a greater correction to the intersection position, to ensure that the intersection with a large degree of deviation returns to the geometric center of the mold cavity 11, and to ensure the consistency of physical properties of the molded metal surface. At this time, the value of c / c0 / 2 is large, and the value of A1=c / c0 / 2+1 is greater than 1 and has a large value. When the control module 3 increases the power of the injection component 2 closest to the peak position by A1 times, it is complete. When the intersection point of the two metal jets deviates from the center of the mold cavity 11 to a large extent, the intersection point is corrected to a large extent; similarly, when c is small, there is no need to significantly increase the power of the injection assembly 2 closest to the peak position. At this time, the value of c / c0 / 2 is small, and the value of A1=c / c0 / 2+1 is greater than 1 and the value is small. When the control module 3 increases the power of the injection assembly 2 closest to the peak position by A1 times, the intersection point of the two metal jets deviates from the center of the mold cavity 11 to a small extent. Correction to the intersection point is completed;

[0049] By enabling the control module 3 to detect the degree of deviation of the metal jets ejected by the two injection assemblies 2 in the double injection system according to the temperature sensor, and then correcting the injection power of the injection assembly 2 according to the degree of deviation, the coincidence degree between the intersection point of the two metal jets and the center of the mold cavity 11 is improved, thereby improving the consistency of physical properties of various surfaces after metal forming.

[0050] To facilitate the input of the values ​​of c0 and p0, the control module 3 is electrically connected to a control panel.

[0051] The present invention also provides a die-casting method under integrated double-shot die-casting, which is applicable to the above-mentioned die-casting mold under integrated double-shot die-casting, and comprises the following steps:

[0052] Step 1: The two injection assemblies 2 respectively press the molten metal into the mold cavity 11;

[0053] Step 2: two pressure sensors respectively detect the pressure of the molten metal in the two injection assemblies 2, and upload the pressure data to the control module 3;

[0054] Step 3: The control module 3 determines whether the difference between the two pressure data is greater than the pressure difference threshold. When the determination result is yes, the control module 3 issues an alarm.

[0055] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A die-casting mold for integrated double-shot die-casting, characterized in that: It includes a template and a mold cavity in the template, wherein the template is provided with two injection assemblies, and the two injection assemblies are respectively used to press molten metal into the mold cavity; Any of the injection components is provided with a pressure sensor, and the two pressure sensors are used to detect the pressure of the molten metal in the injection component. The two pressure sensors are electrically connected to a control module, and the two pressure sensors upload pressure data to the control module. The control module is pre-input with a pressure difference threshold. The control module determines whether the difference between the two pressure data is greater than the pressure difference threshold. When the judgment result is yes, the control module issues an alarm; The control module is electrically connected to the two injection assemblies respectively, and the two injection assemblies are arranged in a one-to-one correspondence with the two pressure sensors. After receiving the pressure data uploaded by the two pressure sensors each time, the control module first compares the two pressure data with the standard values ​​respectively. According to the comparison result of the pressure data, the control module reduces the injection power of the injection assembly corresponding to the pressure data when the pressure data exceeds the standard value, and increases the injection power of the injection assembly corresponding to the pressure data when the pressure data is lower than the standard value; A temperature sensor array is provided in the template, and the temperature sensor array is electrically connected to the control module. The temperature sensor array is used to detect the peak temperature position in the mold cavity and upload the peak position to the control module, and the control module increases the power of the injection component closest to the peak position.

2. The die-casting mold for integrated double-shot die-casting according to claim 1, characterized in that: The control module is pre-input with a pressure standard value p0 and a standard injection power Y0. The two pressure sensors upload the pressure data p1 and p2 to the control module. The control module adjusts the injection power of the injection assembly to Y1 and Y2 according to p1, p2 and p0 respectively. Among them, Y1=p0 / p1×Y0, Y2=p0 / p2×Y0.

3. The die-casting mold for integrated double-shot die-casting according to claim 2, characterized in that: The control module is pre-input with the standard position c0 and the distance c1 between the two injection assemblies. The temperature sensor array is used to detect the peak temperature position in the mold cavity and upload the peak position to the control module. The control module calculates the distance c between the peak temperature position and the standard position, and calculates A1 based on c. The control module increases the power of the injection assembly closest to the peak position by A1 times. Among them, A1=c / c0 / 2+1.

4. The die-casting mold for integrated double-shot die-casting according to claim 3, characterized in that: The control module is electrically connected to a control panel, and the control panel is used to input the values ​​of c0 and p0.

5. A die-casting method under integrated double-shot die-casting, applicable to a die-casting mold under integrated double-shot die-casting according to any one of claims 1 to 4, characterized in that: The following steps are included Step 1: Two injection assemblies press the molten metal into the mold cavity respectively; Step 2: Two pressure sensors respectively detect the pressure of the molten metal in the two injection assemblies, and upload the pressure data to the control module; Step 3: The control module determines whether the difference between the two pressure data is greater than the pressure difference threshold. When the judgment result is yes, the control module issues an alarm.

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