Injection molding system and injection molding method thereof

Abstract

The present invention provides an injection molding system and an injection molding method thereof, wherein the injection molding system includes an injection molding cavity, temperature detection devices are arranged at intervals along the feeding direction of the injection molding cavity, the temperature detection devices are used to detect the temperature value of each section of the injection molding cavity, a plurality of heat exchange units are arranged outside the injection molding cavity, and the injection molding cavity is divided into a first area and a second area according to the state of injection molding feeding. The present invention is provided with a heat exchange unit, which can increase the heating intensity of the segment being injected and the next injection molding segment when the product is injection molded, can ensure that the injection molding material at the front end of the injection molding cavity has good fluidity, and does not need to preheat the mold separately. At the same time, the heat exchange unit can be adaptively reduced according to the cross-sectional dimensions of each section of the injection molding cavity, ensuring that the heat loss rate of each section of the injection molding cavity that has been completed is basically the same, thereby reducing the energy consumption required for heating the mold.

Description

Technical Field

[0001] The invention relates to the field of injection molding, in particular to an injection molding system and an injection molding method thereof. Background Art

[0002] In the process of injection molding of plastic products, in order to enhance the fluidity of the material inside the mold cavity and the molding quality of the molded product, it is necessary to preheat the mold before injection molding and perform thermal compensation on the injection molding material during injection molding. For example, the Chinese patent document with authorization announcement number CN112265235B discloses an injection mold temperature raising and lowering system, heating and cooling methods, which are used to solve the above technical problems.

[0003] To address this problem, technicians added a heating module to the mold. Before use, the heating module is activated to heat the mold to the preheating temperature. During injection molding, the heating module continues to heat the mold to ensure the fluidity of the injection molding material. However, when injecting products with a longer shape, the time required to preheat the mold will increase accordingly, and the energy consumption to maintain the overall heating temperature of the mold will also be very high, resulting in different degrees of increase in the production efficiency and production cost of the injection molding product. Summary of the invention

[0004] Based on this, it is necessary to provide an injection molding system and an injection molding method to address the problems existing in the current injection molds. This system does not require a separate time-consuming process to preheat the mold, and can reduce the energy consumption required to heat the mold while ensuring the fluidity of the injection molding material. At the same time, it can also shorten the time and energy consumption required to cool the mold, thereby improving production efficiency and reducing the company's production costs.

[0005] The above purpose is achieved through the following technical solutions:

[0006] An injection molding system comprises an injection molding cavity, wherein temperature detection devices are arranged at intervals along a feeding direction of the injection molding cavity, and the temperature detection devices are used to detect the temperature value of each section of the injection molding cavity;

[0007] A plurality of heat exchange units are arranged outside the injection cavity, and the injection cavity is divided into a first area and a second area according to the state of the injection feed, wherein the heat exchange unit has a higher heating intensity to the first area than to the second area.

[0008] In one of the embodiments, the injection molding system further includes a timing device, which is used to record the time required for the material to flow out of each section of the injection mold cavity;

[0009] The heating intensity of each section of the injection mold cavity by the heat exchange unit in the second area is positively correlated with the time required for the material to flow out of each section of the injection mold cavity.

[0010] In one embodiment, the heat exchange unit includes a first pipe and a second pipe, and both ends of the first pipe are connected to the second pipe;

[0011] The first pipe is a vertically arranged tubular body, and the axes of the two pipe openings of the second pipe are perpendicular to each other;

[0012] The second pipes are arranged at two ends of the first pipe, and there is a preset distance between the planes where the pipe openings of the two second pipes at one end away from the first pipe are located.

[0013] In one embodiment, a third pipe is provided between two adjacent heat exchange units, the third pipe is a horizontally arranged tubular body, and the third pipe is arranged at an end of the second pipe away from the first pipe;

[0014] The length of the third conduit is variable.

[0015] In one of the embodiments, a moving drive component is disposed outside the first pipe, and the moving drive component is used to drive the heat exchange unit to move along the first guide line.

[0016] In one of the embodiments, the heat exchange units are divided into two groups, and the two groups of heat exchange units are symmetrically arranged on both sides of the injection mold cavity.

[0017] In one of the embodiments, there is a preset gap between the heat exchange unit and the injection mold cavity, and the preset gap is filled with a heat-conducting medium.

[0018] In one embodiment, a heat transfer medium flows inside the first pipe, the second pipe and the third pipe, and the heat transfer medium is either a heating medium or a cooling medium.

[0019] In one embodiment, the first pipe and the second pipe are made of copper or aluminum, and the third pipe is a corrugated hose.

[0020] The present invention also provides an injection molding method, comprising the following steps:

[0021] S100, detecting the temperature value of each section of the injection mold cavity;

[0022] S200, dividing the injection mold cavity into a first area and a second area;

[0023] S300, making the heating intensity of the heat exchange unit on the first area higher than the heating intensity on the second area;

[0024] S400, detecting and recording the time required for the material to flow out of each section of the injection mold cavity;

[0025] S500, making the heating intensity of each section of the injection mold cavity by the heat exchange unit in the second area positively correlated with the time required for the material to flow out of each section of the injection mold cavity.

[0026] The beneficial effects of the present invention are:

[0027] The present invention is provided with a heat exchange unit, which can increase the heating intensity of the segment being injected and the next injection molding segment when the product is injection molded, and can ensure that the injection material at the front end of the injection cavity has good fluidity. There is no need to preheat the mold separately, and at the same time, the heat exchange unit can adaptively reduce the heating intensity of different segments according to the cross-sectional dimensions of each segment of the injection cavity, ensuring that the heat loss rate of each segment of the injection cavity that has been injection molded is basically the same, thereby reducing the energy consumption required for heating the mold, and at the same time shortening the time and energy consumption required for cooling the mold, thereby improving production efficiency and reducing the production cost of the enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0029] Figure 2 It is a structural schematic diagram of the injection mold cavity in the present invention;

[0030] Figure 3 It is a schematic diagram of the connection structure of the heat exchange unit in the present invention;

[0031] Figure 4 This is a schematic diagram of the location of the installation chamber in the present invention;

[0032] Figure 5 It is a structural schematic diagram of the heat exchange unit in the present invention;

[0033] Figure 6 This is a schematic diagram of the position distribution of the heat exchange unit in the injection molding state of the present invention;

[0034] Figure 7 This is a schematic diagram of the position distribution of the heat exchange unit in the injection molding completed state of the present invention.

[0035] in:

[0036] 100, injection mold cavity; 110, feed port; 200, temperature detection device; 300, heat exchange unit; 310, first pipeline; 320, second pipeline; 400, third pipeline; 500, moving component; 600, guide component; 700, lower mold base; 710, installation chamber; 800, upper mold base. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0038] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings). In the description of the present invention, it should be understood that the orientation or position relationship indicated by the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. are based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0039] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0040] like Figure 1-Figure 7 As shown, an injection molding system includes an injection mold cavity 100, and temperature detection devices 200 are arranged at intervals along the feeding direction of the injection mold cavity 100. The temperature detection device 200 is used to detect the temperature value of each section of the injection mold cavity 100. The temperature detection device 200 can specifically be any one of a temperature sensor or a temperature sensor. The installation position of the temperature detection device 200 is preferably arranged at equal intervals along the center line of the injection mold cavity 100, so as to divide the injection mold cavity 100 into a plurality of equally spaced sections, and each temperature detection device 200 only detects the temperature value of the corresponding segment of the injection mold cavity 100.

[0041] Each temperature detection device 200 detects the temperature value of the corresponding segment once per second and sends the temperature value to the system. The system calculates the difference between the temperature value and the previous temperature value. If the difference calculation result is greater than the preset value, it means that the injection molding material has flowed into the segment. The segment area and the area where the material is about to flow are the first area described below.

[0042] For the setting of preset values, the staff can preset them according to the heat transfer speed of the specific mold used. For example, the preset value is set to 20°C. When the temperature value of this test minus the temperature value of the last test is greater than or equal to 20°C, the system determines that the material has flowed into the segment.

[0043] like Figure 1 , Figure 2 and Figure 3 As shown, the injection mold cavity 100 is opened on the upper surface of the lower mold base 700 and the lower surface of the upper mold base 800 , and a feed port 110 is provided at one end of the lower mold base 700 for injecting the injection material into the injection mold cavity 100 .

[0044] A plurality of heat exchange units 300 are arranged outside the injection cavity 100, and the injection cavity 100 is divided into a first area and a second area according to the state of the injection molding feed, wherein the heating intensity of the heat exchange unit 300 to the first area is higher than the heating intensity to the second area, the first area is the area where the injection molding material with good fluidity is located, and the second area is the area where the injection molding material that has been solidified and the injection molding material with reduced fluidity are located.

[0045] The purpose of making the heating intensity of the first area high is to compensate for the heat value lost by the injection molding material, so that the heat loss of the injection molding material in the first area is as small as possible, so that the material in the first area maintains good fluidity and ensures that the injection molding material can flow smoothly to the very end of the injection mold cavity 100. At the same time, making the heating intensity of the first area high can also preheat the area where the material is about to flow, and there is no need to preheat the mold separately, which can shorten the injection time of the injection molded product.

[0046] The heating intensity of the second area is small because the second area is the area where the injection molding has been completed. The injection molding material does not need to have good fluidity. Instead, the fluidity of the injection molding material needs to be reduced so that it gradually solidifies. Therefore, the temperature value of the second area needs to be gradually reduced. The reason why the second area still needs to be heated is to control the speed at which the temperature of each segment of the second area drops to avoid excessive differences in the overall temperature value of the injection molded part, which affects the performance of the injection molded part. At the same time, making the heating intensity of the second area small can also reduce the energy consumption required for heating the mold.

[0047] In one embodiment, the injection molding system also includes a timing device, which is used to record the time required for the material to flow out of each section of the injection mold cavity 100. The timing device can use an existing electronic timing instrument, and its timing needs to be realized through two adjacent temperature detection devices 200. The specific implementation form is as follows: when the temperature detection device 200 located at the rear end of this section detects that the temperature difference reaches a preset value, the timing device on this section starts timing; when the temperature detection device 200 located at the front end of this section detects that the temperature difference reaches a preset value, the timing device stops timing. The calculated time of the timing device is the time required for the material to flow out of each section of the injection mold cavity 100, and then the timing device sends the recorded time value of each section to the system.

[0048] When the cross-sectional size of the segment is larger, the time required for the injection molding material to flow out of the segment is correspondingly longer. Conversely, when the cross-sectional size of the segment is smaller, the time required for the injection molding material to flow out of the segment is correspondingly shorter.

[0049] It should be supplemented that when the injection molding system is used for injection molding, the lower mold base 700 and the upper mold base 800 should be placed at an angle so that the injection material enters the injection mold cavity 100 from bottom to top, so that the material can continue to flow to the next segment after filling each segment.

[0050] The heating intensity of each section of the injection mold cavity 100 by the heat exchange unit 300 in the second area is positively correlated with the time required for the material to flow out of each section of the injection mold cavity 100. What is explained in detail here is that the time required for the material to flow out of each section of the injection mold cavity 100 reflects the cross-sectional size of the injection mold cavity 100 of this section. If the time required for the material to flow out of this section is long, it means that the cross-sectional size of this section is large. If the heat loss rate of this section and other sections is to be basically the same, more heat needs to be compensated for this section. On the contrary, if the cross-sectional size of this section is small, less heat needs to be compensated for this section. In this way, the heat loss rate of each section of the injection mold cavity 100 that has been injection molded can be basically the same, ensuring that the temperature reduction of each section of the injection molded part is uniform.

[0051] In one embodiment, the heat exchange unit 300 includes a first pipe 310 and a second pipe 320 , and both ends of the first pipe 310 are connected to the second pipe 320 ;

[0052] The first pipe 310 is a vertically arranged tubular body, and the axes of the two pipe openings of the second pipe 320 are perpendicular to each other. It is described in detail here that the second pipe 320 is specifically a two-way elbow pipe joint. The planes where the two pipe opening end faces of the second pipe 320 are located are perpendicular to each other for the purpose of facilitating assembly. The first pipe 310 and the second pipe 320 are standard parts, thereby reducing the production cost.

[0053] The second pipes 320 are arranged at both ends of the first pipe 310, and there is a preset distance between the planes where the ends of the two second pipes 320 away from the first pipe 310 are located. It is described in detail here that the preset distance value is a non-zero fixed value. This description is to illustrate that the directions of the ends of the two second pipes 320 away from the first pipe 310 are opposite, such as Figure 3 and Figure 4 As shown, the pipe opening of one second pipe 320 faces the flow direction of the injection material, and the pipe opening of another second pipe 320 faces the opposite direction of the injection material flow. This arrangement facilitates the end-to-end connection of multiple heat exchange units 300.

[0054] In one embodiment, a third pipe 400 is disposed between two adjacent heat exchange units 300. The third pipe 400 is a horizontally disposed tubular body. The third pipe 400 is disposed at one end of the second pipe 320 away from the first pipe 310. The third pipe 400 is used to connect the multiple heat exchange units 300 end to end, so as to facilitate the flow of heat exchange medium in the heat exchange units 300 and the third pipe 400.

[0055] The length of the third pipe 400 is variable, the purpose of which is to change the spacing between two adjacent heat exchange units 300, which is also a specific means for the heat exchange unit 300 to enhance the heating intensity of the first area. By reducing the spacing between two adjacent heat exchange units 300 in the first area, more heat exchange units 300 can be gathered in the first area to perform thermal compensation on the first area, thereby increasing the heating intensity of the heat exchange unit 300 on the first area.

[0056] In one embodiment, a moving assembly 500 is disposed outside the first pipe 310. The moving assembly 500 is used to drive the heat exchange unit 300 to move along a first guide line. The first guide line is specifically a straight line parallel to the center line of the injection mold cavity 100. The movement of the moving assembly 500 is controlled by the system. The system controls the movement of the moving assembly 500, and the moving assembly 500 drives the corresponding heat exchange unit 300 to move, thereby realizing the aggregation of the heat exchange units 300 in the first area and the adaptive arrangement of the heat exchange units 300 in the second area. Figure 6 As shown, the heat exchange units 300 are concentrated in the first area to heat it. Figure 7 As shown, at this time, the injection molded product inside the injection cavity 100 has been injection molded, and all areas of the injection cavity 100 are the second area. At this time, the heat exchange units 300 form a positively correlated distribution according to the different cross-sectional sizes of each segment. There are more heat exchange units 300 distributed in segments with large cross-sectional sizes, and there are fewer heat exchange units 300 distributed in segments with small cross-sectional sizes.

[0057] In one embodiment, the heat exchange unit 300 is divided into two groups, and the two groups of heat exchange units 300 are symmetrically arranged on both sides of the injection cavity 100. Such an arrangement is used to perform thermal compensation on both sides of the injection cavity 100 so that the temperature changes on both sides of the injection cavity 100 are consistent.

[0058] In one embodiment, there is a preset gap between the heat exchange unit 300 and the injection mold cavity 100, and the preset gap is filled with a heat-conducting medium, such as Figures 1 to 4 As shown, installation chambers 710 are opened on both sides of the lower mold base 700, and a group of heat exchange units 300 are arranged in each installation chamber 710, wherein there is a preset gap between the heat exchange unit 300 and the injection mold cavity 100. In order to improve the heat transfer efficiency, the preset gap can be filled with a medium that can increase the thermal conductivity, such as placing a metal plate or silicone sheet with good thermal conductivity.

[0059] A guide assembly 600 is also provided inside the installation chamber 710, and the guide assembly 600 enables the moving assembly 500 to move linearly along the guide assembly 600. The moving assembly 500 may specifically be a power trolley or other device capable of achieving linear movement, and the guide assembly 600 may specifically be a guide plate or guide rail adapted to the moving assembly 500.

[0060] In one embodiment, a heat transfer medium flows inside the first pipe 310, the second pipe 320 and the third pipe 400, and the heat transfer medium is either a heating medium or a cooling medium. When the injection molded product inside the injection cavity 100 is not injection molded, the heating medium flows inside the first pipe 310, the second pipe 320 and the third pipe 400 to perform thermal compensation on the injection molded material in the injection cavity 100; after the injection molded material inside the injection cavity 100 is injection molded, it is necessary to cool down the lower mold base 700, the upper mold base 800 and the injection molded product inside the injection cavity 100, and the heat transfer medium can be replaced with a cooling medium for cooling down, such as replacing hot water with normal temperature water.

[0061] Since the heating intensity of the second area is reduced, the time and energy consumption required for cooling the mold and the injection molded product inside the injection cavity 100 will also be reduced, thereby improving production efficiency and reducing the production cost of the enterprise.

[0062] In one embodiment, the material of the first pipe 310 and the second pipe 320 is copper or aluminum, and the third pipe 400 is a corrugated hose. The reason for using copper or aluminum is that copper or aluminum has good thermal conductivity and can efficiently transfer the heat of the heat-conducting medium to the lower mold base 700, thereby heating the injection mold cavity 100. The reason why the third pipe 400 is a corrugated hose is that the corrugated hose has good compression and tensile properties, as well as good thermal conductivity, resulting in lower cost and meeting the actual needs of industrial production.

[0063] The present invention also provides an injection molding method, comprising the following steps:

[0064] S100, detecting the temperature value of each section of the injection mold cavity 100;

[0065] S200, dividing the injection mold cavity 100 into a first area and a second area;

[0066] S300, making the heating intensity of the heat exchange unit 300 on the first area higher than the heating intensity on the second area;

[0067] S400, detecting and recording the time required for the material to flow out of each section of the injection mold cavity 100;

[0068] S500, making the heating intensity of each section of the injection mold cavity 100 by the heat exchange unit 300 in the second area positively correlated with the time required for the material to flow out of each section of the injection mold cavity 100.

[0069] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An injection molding system, characterized in that: It includes an injection mold cavity, and temperature detection devices are arranged at intervals along the feeding direction of the injection mold cavity, and the temperature detection devices are used to detect the temperature value of each section of the injection mold cavity; A plurality of heat exchange units are arranged outside the injection mold cavity, and the injection mold cavity is divided into a first area and a second area according to the state of the injection feed, wherein the heat exchange unit has a higher heating intensity for the first area than for the second area; the injection molding system further includes a timing device, which is used to record the time required for the material to flow out of each section of the injection mold cavity; The heating intensity of the heat exchange unit in the second area on each section of the injection mold cavity is positively correlated with the time required for the material to flow out of each section of the injection mold cavity; the heat exchange unit includes a first pipe and a second pipe, and both ends of the first pipe are connected to the second pipe; The first pipe is a vertically arranged tubular body, and the axes of the two pipe openings of the second pipe are perpendicular to each other; The second pipes are arranged at both ends of the first pipe, and there is a preset distance between the planes where the ends of the two second pipes away from the first pipe are located; a third pipe is arranged between two adjacent heat exchange units, the third pipe is a horizontally arranged tubular body, and the third pipe is arranged at one end of the second pipe away from the first pipe; The length of the third pipeline is variable; a mobile driving component is arranged outside the first pipeline, and the mobile driving component is used to drive the heat exchange unit to move along the first guide line; a heat transfer medium flows inside the first pipeline, the second pipeline and the third pipeline, and the heat transfer medium is either a heating medium or a cooling medium.

2. An injection molding system according to claim 1, characterized in that: The heat exchange units are divided into two groups, and the two groups of heat exchange units are symmetrically arranged on both sides of the injection mold cavity.

3. An injection molding system according to claim 2, characterized in that: A preset gap is provided between the heat exchange unit and the injection mold cavity, and the preset gap is filled with a heat-conducting medium.

4. An injection molding system according to claim 1, characterized in that: The first pipe and the second pipe are made of copper or aluminum, and the third pipe is a corrugated hose.

5. An injection molding method, characterized in that: The method is implemented according to an injection molding system according to any one of claims 1 to 4, and comprises the following steps: S100, detecting the temperature value of each section of the injection mold cavity; S200, dividing the injection mold cavity into a first area and a second area; S300, making the heating intensity of the heat exchange unit on the first area higher than the heating intensity on the second area; S400, detects and records the time required for the material to flow out of each section of the injection mold cavity; S500, making the heating intensity of each section of the injection mold cavity by the heat exchange unit in the second area positively correlated with the time required for the material to flow out of each section of the injection mold cavity.

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