Temperature control system for injection mold

Abstract

The utility model provides an injection mold temperature control system which comprises a heater and a refrigerating machine, nitrogen is introduced into the gas inlet ends of the heater and the refrigerating machine, and the gas outlet ends of the heater and the refrigerating machine are communicated with the gas inlet end of an injection mold through a nitrogen input pipeline; and nitrogen return pipelines are arranged among the heater, the refrigerating machine and the gas outlet end of the injection mold. The nitrogen is used for replacing media such as water, oil, water vapor and a heating rod, the nitrogen heating and refrigerating integrated technology is adopted in combination with equipment such as a nitrogen making machine, a heater and a refrigerating machine, the temperature of the injection mold is adjusted, and the device has the advantages that the environment and injection products are not polluted, and the injection production period is shortened.

Description

Technical Field

[0001] The utility model relates to the field of injection molds, in particular to an injection mold temperature control system. Background Art

[0002] PEEK material injection molding products have requirements for the high gloss surface and crystallinity of the products. Generally, the mold temperature needs to reach above 180°C for injection molding. After molding, the mold needs to be cooled quickly to ensure that the size, deformation, appearance, etc. of the product after demolding can meet the design requirements.

[0003] Two temperature control schemes are commonly used in the prior art. Scheme 1: After the injection mold is heated at high temperature, it is cooled naturally or by cooling water. The high-temperature heating methods include water heating, electric heating, oil heating, etc., such as the mold temperature control system disclosed in patent numbers CN1435309A and CN101013327A. Scheme 2: The injection mold adopts integrated technology of steam heating and cooling water refrigeration. In Scheme 1, water heating can only reach a temperature of 100°C, which cannot meet the requirements of higher temperature molds; electric heating, the heating channel is closed, and the mold heats up slowly and cools slowly when not heated, and the mold cannot achieve the integrated effect of rapid heating and cooling of the mold; oil heating, it is difficult to avoid oil leakage when replacing the mold loading and unloading oil circuit, so as to contaminate the mold and the product, especially the medical device industry with high requirements for cleanliness and biocompatibility is not applicable; the natural cooling mold cannot reach the ideal cooling temperature, and the production cycle is long; cooling water cooling, it is difficult to avoid water leakage when replacing the mold loading and unloading water circuit, so as to contaminate the mold and the product. In the second scheme, steam heating can meet the high temperature processing requirements of the mold, but it requires the use of a steam high pressure machine or steam boiler, which has a high purchase cost, and the high steam pressure will increase the cost of safety maintenance in the later stage; cooling water refrigeration also faces the problem of water leakage and contamination of the mold and product. Therefore, a temperature control system for injection molds is needed that does not pollute the environment and injection molded products and has a short production cycle. Summary of the invention

[0004] In view of this, the utility model proposes an injection mold temperature control system which does not pollute the environment and the injection molded product and has a short production cycle.

[0005] The technical solution of the utility model is implemented as follows: on the one hand, an injection mold temperature control system is provided, comprising a heater and a refrigerator, nitrogen is introduced into the air inlet ends of the heater and the refrigerator, and the air outlet ends of the heater and the refrigerator are connected to the air inlet end of the injection mold through a nitrogen input pipeline; a reflux pipeline is provided between the heater, the refrigerator and the air outlet end of the injection mold.

[0006] On the basis of the above technical solution, preferably, it further comprises a nitrogen generator, and the nitrogen generator is connected with the heater and the refrigerator through a nitrogen circulation pipeline.

[0007] On the basis of the above technical solution, preferably, the nitrogen circulation pipeline includes a first regulating valve, a first pipeline, a second pipeline, a fourth regulating valve and a second nitrogen reflux pipe.

[0008] On the basis of the above technical solution, preferably, the nitrogen input pipeline includes a nitrogen inlet pipe, a third pipeline, a fourth pipeline, and a second regulating valve; the nitrogen inlet pipe is provided with a second regulating valve, the second regulating valve is connected to a third pipeline and a fourth pipeline, the third pipeline is connected to the gas outlet end of the heater, and the fourth pipeline is connected to the gas outlet end of the refrigerator.

[0009] On the basis of the above technical solution, preferably, the nitrogen reflux pipeline includes a first nitrogen reflux pipe, a fifth pipeline, a sixth pipeline and a third regulating valve; the first nitrogen reflux pipe is provided with a third regulating valve, the third regulating valve is connected to the fifth pipeline and the sixth pipeline, the fifth pipeline is connected to the heater, and the sixth pipeline is connected to the refrigerator.

[0010] On the basis of the above technical solution, preferably, the output end of the nitrogen generator is provided with a first regulating valve, the first regulating valve is connected to a first pipeline and a second pipeline, the first pipeline is connected to the air inlet end of the heater, and the second pipeline is connected to the air inlet end of the refrigerator; the refrigerator is provided with a fourth regulating valve, the fourth regulating valve is connected to the second nitrogen reflux pipe, and is connected to the nitrogen generator through the second nitrogen reflux pipe.

[0011] On the basis of the above technical solution, preferably, a fifth regulating valve is provided outside the injection mold, and the nitrogen inlet pipe and the first nitrogen return pipe are both connected to the fifth regulating valve.

[0012] On the basis of the above technical solution, preferably, a circulation channel surrounding the injection workpiece core is provided inside the injection mold, the air inlet of the circulation channel is connected to the nitrogen inlet pipe through the fifth regulating valve, and the air outlet of the circulation channel is connected to the nitrogen first reflux pipe through the fifth regulating valve.

[0013] On the basis of the above technical solution, preferably, a PLC controller is also included, and the nitrogen generator, heater, refrigerator, injection mold, first regulating valve, second regulating valve, third regulating valve, fourth regulating valve and fifth regulating valve are all electrically connected to the PLC controller through terminals.

[0014] On the basis of the above technical solution, preferably, a temperature sensing rod is provided in the injection mold, and the temperature sensing rod is electrically connected to the PLC controller through a terminal.

[0015] On the other hand, a control method for an injection mold temperature control system is provided, comprising the following steps:

[0016] S1, when the injection mold is opened, the PLC controller turns on the nitrogen generator, the injection mold transmits a signal to the PLC controller through the terminal, the PLC controller controls the first regulating valve to open the first pipeline, close the second pipeline, and then turn on the heater; the nitrogen is heated to a predetermined temperature and fed back to the PLC controller, the PLC controller controls the second regulating valve to open the nitrogen inlet pipe, close the fourth pipeline, and the high-temperature nitrogen is delivered to the injection mold through the fifth regulating valve; when the fifth regulating valve senses the nitrogen pressure in the outlet channel, the PLC controller controls the third regulating valve to open the first nitrogen reflux pipe and the fifth pipeline, and close the sixth pipeline;

[0017] S2, when the injection mold is closed, the injection mold transmits a signal to the PLC controller through the terminal, and the PLC controller controls the first regulating valve to close the first pipeline and open the second pipeline; the PLC controller controls the third regulating valve to close the fifth pipeline and open the sixth pipeline;

[0018] S3, the PLC controller turns on the refrigerator and turns off the heater. After the nitrogen refrigeration temperature reaches the set temperature, it is fed back to the PLC controller. The PLC controller controls the second regulating valve, closes the high-temperature nitrogen inlet, opens the fourth pipeline and the nitrogen inlet pipe; the cooling nitrogen is transported to the injection mold through the fifth regulating valve, and the cooling nitrogen circulates inside the mold and then flows back to the refrigerator.

[0019] On the basis of the above technical solution, preferably, when the nitrogen pressure in the refrigerator is too high, a signal is transmitted to the PLC controller through the terminal, and the PLC controller controls the fourth regulating valve, and the nitrogen flows back to the nitrogen generator through the second nitrogen return pipe; when the nitrogen pressure in the refrigerator is too low, a signal is transmitted to the PLC controller through the terminal, and the PLC controller controls the nitrogen generator to increase the delivery pressure.

[0020] The temperature control system of an injection mold of the utility model has the following beneficial effects compared with the prior art:

[0021] (1) Nitrogen is a non-toxic gas with abundant resources. Nitrogen is in gaseous state when heating the mold to above 180°C and cooling the mold to within -196°C, which is conducive to integrated transportation and regulation. The utility model uses nitrogen to replace water, oil, water vapor, heating rods and other media, and combines nitrogen generators, heaters, refrigerators and other equipment to adopt nitrogen heating and cooling integrated technology to adjust the temperature of the injection mold, which has the advantages of not polluting the environment and the injection molded products and shortening the injection molding production cycle.

[0022] (2) In the nitrogen temperature control system of the utility model, the heater and the refrigerator are connected in parallel, and the heating link and the cooling link are completed in separate cycles without interfering with each other. The nitrogen generator can be filled with new nitrogen at any time for heat exchange and pressure compensation.

[0023] (3) The nitrogen temperature control system of the utility model is connected to the injection mold opening and closing process, synchronously senses the nitrogen temperature and pressure, and intelligently controls the cyclic operation of the nitrogen generator, heater, and refrigerator, so as to realize the rapid and orderly switching of high-temperature nitrogen and low-temperature nitrogen and deliver them to the injection mold, thus realizing the integrated technology of high-temperature heating and low-temperature cooling of the injection mold. (4) The internal channel of the injection mold is evenly distributed in the three directions of X, Y, and Z axes to surround the injection mold core, so that the core temperature is better transferred and dissipated by nitrogen. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 This is a structural diagram of the temperature control system of the injection mold of the utility model;

[0026] Figure 2 It is a structural diagram of the injection mold in the temperature control system of the injection mold of the utility model;

[0027] Figure 3 It is a cross-sectional view of the injection mold in the injection mold temperature control system of the utility model.

[0028] In the figure, 1-heater, 2-refrigerator, 3-nitrogen inlet pipe, 4-injection mold, 100-nitrogen input pipeline 、 200-nitrogen reflux pipeline, 300-nitrogen circulation pipeline, 41-injection workpiece core, 42-circulation channel, 43-temperature sensing rod, 44-front mold, 45-rear mold, 5-nitrogen first reflux pipe, 6-nitrogen generator, 11-first regulating valve, 12-second regulating valve, 13-third regulating valve, 14-fourth regulating valve, 15-fifth regulating valve, 21-first pipeline, 22-second pipeline, 23-third pipeline, 24-fourth pipeline, 25-fifth pipeline, 26-sixth pipeline, 27-nitrogen second reflux pipe, 7-PLC controller, 8-1 to 8-10 are all terminals. DETAILED DESCRIPTION

[0029] The following will be combined with the implementation of the utility model to clearly and completely describe the technical solutions in the implementation of the utility model. Obviously, the described implementation is only a part of the implementation of the utility model, not all of the implementations. Based on the implementation of the utility model, all other implementations obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0030] In the description of the utility model, it is necessary to understand that "first, second" and the like are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. The first regulating valve 11, the second regulating valve 12, the third regulating valve 13, the fourth regulating valve 14 and the fifth regulating valve 15 mentioned in the text are all multi-way valves. The first pipeline 21, the second pipeline 22, the third pipeline 23, the fourth pipeline 24, the fifth pipeline 25, the sixth pipeline 26, the first nitrogen return pipe 5 and the second nitrogen return pipe 27 are all pipelines resistant to high and low temperatures.

[0031] In order to solve the safety hazards and long cycle problems of using water, electricity and steam heating in the existing technology, the utility model adopts nitrogen as the medium material, heating heat transfer and cooling heat dissipation to achieve the high and low temperature adjustment requirements of the mold, and develops a nitrogen fast heating and cooling system.

[0032] like Figure 1-3 As shown, the structure of the system is specifically as follows: it includes a heater 1, a refrigerator 2, a nitrogen input pipeline 100 and a nitrogen reflux pipeline 200. Nitrogen is introduced into the air inlet of the heater 1 and the refrigerator 2. The source of nitrogen is purchased nitrogen or nitrogen produced by a nitrogen generator, which provides a temperature control medium for the system. The function of the heater 1 is to heat the nitrogen to a predetermined high temperature for the injection mold 4; the function of the refrigerator 2 is to cool the nitrogen to a predetermined low temperature for the injection mold 4. The air outlets of the heater 1 and the refrigerator 2 are connected to the air inlet of the injection mold 4 through the nitrogen input pipeline 100; a nitrogen reflux pipeline 200 is provided between the heater 1, the refrigerator 2 and the air outlet of the injection mold 4, and the nitrogen reflux pipeline 200 is used for the reflux of high-temperature nitrogen and low-temperature nitrogen, which plays a role in nitrogen recycling.

[0033] The nitrogen source of this embodiment is nitrogen generator 6, and the function of nitrogen generator 6 is to prepare nitrogen from air and provide temperature control medium for the system. Nitrogen generator 6 is connected to heater 1 and refrigerator 2 through nitrogen circulation pipeline 300, and nitrogen circulation pipeline 300 includes first regulating valve 11, first pipeline 21, second pipeline 22, fourth regulating valve 14 and nitrogen second reflux pipe 27. The specific structure is: the output end of nitrogen generator 6 is provided with first regulating valve 11, first regulating valve 11 is connected with first pipeline 21 and second pipeline 22, first pipeline 21 is connected with air inlet end of heater 1, and second pipeline 22 is connected with air inlet end of refrigerator 2. Whether nitrogen enters heating system or refrigeration system can be adjusted by first regulating valve 11.

[0034] In a specific embodiment, the nitrogen input pipeline 100 includes a nitrogen inlet pipe 3, a third pipeline 23, a fourth pipeline 24 and a second regulating valve 12. The nitrogen return pipeline 200 includes a nitrogen first return pipe 5, a fifth pipeline 25, a sixth pipeline 26 and a third regulating valve 13. The specific structure is: the nitrogen inlet pipe 3 is provided with a second regulating valve 12, the second regulating valve 12 is respectively connected to the third pipeline 23 and the fourth pipeline 24, the third pipeline 23 is connected to the outlet end of the heater 1, and the fourth pipeline 24 is connected to the outlet end of the refrigerator 2. The nitrogen first return pipe 5 is provided with a third regulating valve 13, the third regulating valve 13 is respectively connected to the fifth pipeline 25 and the sixth pipeline 26, the fifth pipeline 25 is connected to the heater 1, and the sixth pipeline 26 is connected to the refrigerator 2. The high-temperature nitrogen generated by the heater 1 passes through the third pipeline 23, the second regulating valve 12, and the nitrogen inlet pipe 3 in sequence to enter the air inlet of the injection mold 4. After internal circulation heating, it passes through the nitrogen first reflux pipe 5, the third regulating valve 13 and the fifth pipeline 25 in sequence to flow back to the heater 1, completing the nitrogen heating cycle.

[0035] The low-temperature nitrogen generated by the refrigerator 2 enters the air inlet of the injection mold 4 through the fourth pipeline 24, the second regulating valve 12, and the nitrogen inlet pipe 3 in sequence. After internal circulation cooling, it flows back to the refrigerator 2 through the nitrogen first reflux pipe 5, the third regulating valve 13 and the sixth pipeline 26 in sequence, completing the nitrogen cooling cycle.

[0036] Specifically, the nitrogen inlet pipe 3 and the nitrogen first return pipe 5 are common pipes for heating and cooling, which saves pipe connections and achieves more effective heating and cooling of the mold.

[0037] In a specific embodiment, in order to control the internal pressure of the refrigerator 2, the present embodiment is further provided with a second nitrogen return pipe 27. Specifically, the refrigerator 2 is provided with a fourth regulating valve 14, one end of the second nitrogen return pipe 27 is connected to the fourth regulating valve 14, and the other end is connected to the nitrogen generator 6. During the nitrogen heating or cooling cycle, the nitrogen generator can monitor the nitrogen filling pressure and adjust the predetermined pressure value by itself. When the nitrogen generator 6 detects that the nitrogen filling pressure exceeds the predetermined pressure value, the second nitrogen return pipe 27 can be opened through the fourth regulating valve 14 to reflux a part of the nitrogen to the nitrogen generator 6.

[0038] In a specific embodiment, the injection mold 4 is provided with a fifth regulating valve 15, and the nitrogen inlet pipe 3 and the first nitrogen return pipe 5 are both connected to the fifth regulating valve 15. The fifth regulating valve 15 has a pressure sensing function, and transmits a signal to the PLC controller 7 by sensing the pressure of the first nitrogen return pipe 5. The PLC controller 7 controls the third regulating valve 13, and opens the third regulating valve 13 to the fifth pipeline 25 during the heating cycle. ， During the refrigeration cycle, the third regulating valve 13 is opened to the sixth pipeline 26 to complete the reflux cycle of nitrogen heating or cooling.

[0039] Specifically, a circulation channel 42 surrounding the injection workpiece core 41 is provided inside the injection mold 4, the air inlet of the circulation channel 42 is connected to the nitrogen inlet pipe 3 through the fifth regulating valve 15, and the air outlet of the circulation channel 42 is connected to the nitrogen first reflux pipe 5 through the fifth regulating valve 15.

[0040] In a specific embodiment, in order to realize automatic control, a PLC controller 7 is provided in this embodiment, and the nitrogen generator 6, the heater 1, the refrigerator 2, the injection mold 4, the first regulating valve 11, the second regulating valve 12, the third regulating valve 13, the fourth regulating valve 14 and the fifth regulating valve 15 are all electrically connected to the PLC controller 7 through terminals and are electrically controlled by the PLC controller 7.

[0041] In a specific embodiment, a temperature sensing rod 43 is provided in the injection mold 4, and the temperature sensing rod 43 is electrically connected to the PLC controller 7 through a terminal, so that the PLC controller 7 can monitor the heating temperature and the cooling temperature of the heater 1 and the refrigerator 2 in real time through the terminal.

[0042] In a specific embodiment, a pressure pump is provided inside the heater 1 and the refrigerator 2 and can sense the internal pressure value. When the heater 1 and the refrigerator 2 are in operation, the pressure pump works synchronously. When the pressure pump in the heater 1 and the refrigerator 2 senses that the nitrogen delivery pressure value exceeds the preset pressure value, the first regulating valve 11 is closed, and the nitrogen generator 6 does not deliver nitrogen to the control system. The operation of the pressure pump can meet the pressure in the pipeline to self-sufficiently circulate high-temperature nitrogen and low-temperature nitrogen.

[0043] The control method of the temperature control system of the injection mold of the utility model has the following specific steps:

[0044] S1, turn on the power and start the nitrogen generator 6.

[0045] S2, the injection mold 4 is set to the mold opening state, and a signal is transmitted to the PLC controller 7 through the terminal 8-8; the PLC controller 7 transmits a signal to the first regulating valve 11 through the terminal 8-2, opens the first pipeline 21, and closes the second pipeline 22.

[0046] S3, the PLC controller 7 sends a signal to the heater 1 through the terminal 8-3 to start the operation. After the nitrogen heating temperature reaches the predetermined temperature, it is fed back to the PLC controller 7 through the terminal 8-3. The PLC controller 7 sends a signal to the second regulating valve 12 through the terminal 8-7. The second regulating valve 12 opens the high-temperature nitrogen inlet of the nitrogen inlet pipe 3 and closes the fourth pipeline 24.

[0047] S4, high-temperature nitrogen is transported to the injection mold 4 through the fifth regulating valve 15. A circulation channel 42 is designed inside the mold. Nitrogen enters the internal channel of the mold and flows to the channel outlet. After the fifth regulating valve 15 senses the nitrogen pressure at the channel outlet, it transmits a signal to the PLC controller 7 through terminals 8-9. The PLC controller 7 transmits a signal to the third regulating valve 13 through terminals 8-6. The third regulating valve 13 opens the nitrogen inlet of the first nitrogen reflux pipe 5 and the nitrogen outlet of the fifth pipeline 25, and closes the sixth pipeline 26.

[0048] The nitrogen gas flows back to the heater 1 for reheating and transportation, and the mold heating cycle is repeated according to the S2-S4 process. During the heating cycle, when the pressure pump in the heater 1 senses that the nitrogen pressure value exceeds the predetermined value, the first regulating valve 11 is closed to stop the nitrogen supply of the nitrogen generator, and the pressure pump in the heater 1 runs until the injection mold 4 mold closing signal in the following step S5 is given to the PLC controller 7. The heating cycle process is controlled by the process from the injection mold opening signal in the above step S2 to the injection mold closing signal in the following step S5 by the PLC controller 7. The time from the injection mold 4 opening to the mold closing process is set by the injection molding machine's own system. In addition to ensuring the orderly production of mold opening and taking out, this time parameter setting also needs to refer to the actual effect of the high-temperature nitrogen before the injection molding machine closes the mold to heat the mold to the ideal temperature. The setting method is to increase or decrease the opening and closing speed, the taking out speed, the mold closing delay time, etc.

[0049] S5, when the mold opening to mold closing time parameters set by the injection molding machine run to the time when the injection mold 4 is closed, a signal is transmitted to the PLC controller 7 through terminal 8-8, and the PLC controller 7 transmits a signal to the first regulating valve 11 through terminal 8-2, closing the first pipeline 21, that is, closing the channel for nitrogen to be delivered to the heater 1, and opening the second pipeline 22; the PLC controller 7 controls the third regulating valve 13 through terminal 8-6, closing the fifth pipeline 25, that is, closing the channel for nitrogen to flow back to the heater 1; and opening the sixth pipeline 26, that is, opening the channel for nitrogen to flow back to the refrigerator 2.

[0050] S6, PLC controller 7 sends a signal to refrigerator 2 through terminal 8-4 to start operation, and sends a signal to heater 1 through terminal 8-3 to stop operation. After the nitrogen refrigeration temperature reaches the set temperature, it is fed back to PLC controller 7 through terminal 8-4. PLC controller 7 sends a signal to second regulating valve 12 through terminal 8-7, closes the high-temperature nitrogen inlet, opens the fourth pipeline 24 to cool the nitrogen inlet, and opens the nitrogen inlet pipe 3 to cool the nitrogen outlet. The cooling nitrogen is transported to the injection mold 4 through the fifth regulating valve 15. After the cooling nitrogen circulates inside the mold, it passes through the fifth regulating valve 15 to the first nitrogen return pipe 5, then to the sixth pipeline 26, and finally flows back to the refrigerator 2.

[0051] S7, when the refrigeration machine 2 senses that the reflux nitrogen pressure exceeds the preset pressure value, the PLC controller 7 is fed back through terminal 8-4, and the PLC controller 7 controls the first regulating valve 11 to close through terminal 8-2, and the PLC controller 7 controls the fourth regulating valve 14 to open the nitrogen second reflux pipe 27 through terminal 8-5, and the nitrogen flows back to the nitrogen generator 6 until the refrigeration machine 2 senses that the reflux nitrogen pressure reaches the preset pressure value, and the PLC controller 7 controls the fourth regulating valve 14 to close through terminal 8-5.

[0052] The nitrogen gas flows back to the refrigerator 2 and then refrigerates and transports, and repeats the refrigeration cycle of the injection mold 4 according to the S6-S7 process. The refrigeration cycle process is controlled by the PLC controller 7 sensing the process from the injection molding machine mold closing signal in step S5 to the injection molding machine mold opening signal in step S2. The time parameters of the injection mold closing to mold opening process are set by the injection molding machine's own system. In addition to ensuring the orderly production of mold closing and molding products, this time parameter setting also needs to refer to the actual effect of low-temperature nitrogen on the mold cooling to the ideal temperature before the injection mold 4 is opened. The simplest setting method is to lengthen or shorten the cooling time of the injection molding machine.

[0053] S8, during continuous production, the injection mold 4 is opened and closed, and the mold is repeatedly heated and cooled according to the process description of S2-S8.

[0054] like Figure 2 As shown, the injection mold 4 includes a front mold 44 and a rear mold 45, and a temperature sensing rod 43 is installed on the front mold 44 and the rear mold 45. The temperature sensing rod 44 signal is connected to the PLC controller 7 through the terminal 8-10, so that the PLC controller 7 can monitor the mold temperature in the heating circulation system and the cooling circulation system of the heater 1 and the refrigerator 2 in real time through the terminal 8-3 and the terminal 8-4 respectively.

[0055] The front mold 44 and the rear mold 45 are both provided with a nitrogen circulation channel 42. The internal cross-sectional view of the circulation channel 42 is as follows: Figure 3 As shown, the nitrogen inlet and outlet directions are designed to be evenly distributed in the three directions of X-axis, Y-axis and Z-axis to surround the injection mold core 41 of the injection molded workpiece, so as to achieve the fastest heating and cooling effect of the mold.

[0056] Specifically, the heater 1 and the refrigerator 2 are both provided with pressure pumps and can sense the nitrogen pressure value inside them. When the heater 1 and the refrigerator 2 are in operation, the pressure pumps work synchronously. The nitrogen generated by the nitrogen generator 6 is delivered to the heating system and the refrigeration system, and the nitrogen is discharged in a cycle without leakage. The pressure value will accumulate and increase. When the pressure pump senses that the nitrogen pressure value inside the heater 1 and the refrigerator 2 exceeds the predetermined value, the first regulating valve 11 is closed, and the pressure pump can work to meet the pressure in the pipeline to self-sufficiently circulate high-temperature nitrogen and low-temperature nitrogen.

[0057] The implementation case comparison uses the system and control method for adjusting the temperature of the injection mold of the utility model and the previous mold temperature control method, and selects the medical device PEEK material interface nail product for verification and comparison. The production cycle of the PEEK material interface nail product is relatively long, and the control system used in this case experiment to control the heating and cooling rates is more compatible.

[0058] The mold has one cavity and one mold, and the mold temperature is required to be set at 190°C. The production cycle, production volume, product ejection temperature, defective rate, etc. are taken for data collection and comparative analysis.

[0059] Table 1 Comparison of qualified rate and contamination rate of products in the embodiments and comparative examples

[0060]

[0061]

[0062] According to the above table data analysis, compared with comparative examples 1 and 2, the use of the system and control method for adjusting the temperature of the injection mold of the utility model significantly increases the output of the final molded product, and significantly reduces the defective rate and the probability of product contamination. From the surface temperature of the product out of the mold, it can be seen that the temperature control method of the utility model can better control the mold temperature while significantly improving the qualified rate, and the products produced by the utility model can be put into the subsequent process more quickly.

[0063] The utility model has been verified by experiments that the temperature of the mold can reach the set temperature after heating and cooling. The injection molded product is molded in the high-temperature mold and removed from the mold after cooling down the low-temperature mold. The product quality meets the requirements and the production cycle is significantly shortened compared with the traditional technical solution.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An injection mold temperature control system, characterized in that: The invention comprises a heater (1) and a refrigerator (2), wherein nitrogen is introduced into the air inlet ends of the heater (1) and the refrigerator (2), and the air outlet ends of the heater (1) and the refrigerator (2) are connected to the air inlet end of the injection mold (4) through a nitrogen input pipeline (100); and a nitrogen return pipeline (200) is provided between the heater (1), the refrigerator (2) and the air outlet end of the injection mold (4).

2. An injection mold temperature control system as claimed in claim 1, characterized in that: It also includes a nitrogen generator (6), which is connected to the heater (1) and the refrigerator (2) through a nitrogen circulation pipeline (300).

3. An injection mold temperature control system as claimed in claim 2, characterized in that: The nitrogen circulation pipeline (300) comprises a first regulating valve (11), a first pipeline (21), a second pipeline (22), a fourth regulating valve (14) and a second nitrogen reflux pipe (27).

4. An injection mold temperature control system as claimed in claim 2, characterized in that: The nitrogen input pipeline (100) comprises a nitrogen inlet pipe (3), a third pipeline (23), a fourth pipeline (24), and a second regulating valve (12); the nitrogen inlet pipe (3) is provided with a second regulating valve (12), the second regulating valve (12) is connected to the third pipeline (23) and the fourth pipeline (24), the third pipeline (23) is connected to the gas outlet end of the heater (1), and the fourth pipeline (24) is connected to the gas outlet end of the refrigerator (2).

5. An injection mold temperature control system as claimed in claim 4, characterized in that: The nitrogen reflux pipeline (200) comprises a first nitrogen reflux pipeline (5), a fifth pipeline (25), a sixth pipeline (26) and a third regulating valve (13); the first nitrogen reflux pipeline (5) is provided with a third regulating valve (13), the third regulating valve (13) is connected to the fifth pipeline (25) and the sixth pipeline (26), the fifth pipeline (25) is connected to the heater (1), and the sixth pipeline (26) is connected to the refrigerator (2).

6. An injection mold temperature control system as claimed in claim 3, characterized in that: The output end of the nitrogen generator (6) is provided with a first regulating valve (11), the first regulating valve (11) being connected to a first pipeline (21) and a second pipeline (22), the first pipeline (21) being in communication with an air inlet end of the heater (1), and the second pipeline (22) being in communication with an air inlet end of a refrigerator (2); the refrigerator (2) is provided with a fourth regulating valve (14), the fourth regulating valve (14) being connected to a second nitrogen return pipe (27), and being in communication with the nitrogen generator (6) via the second nitrogen return pipe (27).

7. An injection mold temperature control system as claimed in claim 5, characterized in that: A fifth regulating valve (15) is provided outside the injection mold (4), and the nitrogen inlet pipe (3) and the first nitrogen return pipe (5) are both connected to the fifth regulating valve (15).

8. An injection mold temperature control system according to claim 7, characterized in that: A circulation channel (42) surrounding an injection workpiece core (41) is provided inside the injection mold (4); an air inlet of the circulation channel (42) is connected to a nitrogen inlet pipe (3) via a fifth regulating valve (15); and an air outlet of the circulation channel (42) is connected to a nitrogen first return pipe (5) via a fifth regulating valve (15).

9. An injection mold temperature control system as claimed in claim 8, characterized in that: The invention also comprises a PLC controller (7), wherein the nitrogen generator (6), the heater (1), the refrigerator (2), the injection mold (4), the first regulating valve (11), the second regulating valve (12), the third regulating valve (13), the fourth regulating valve (14) and the fifth regulating valve (15) are all electrically connected to the PLC controller (7) via terminals.

10. An injection mold temperature control system according to claim 9, characterized in that: A temperature sensing rod (43) is provided in the injection mold (4), and the temperature sensing rod (43) is electrically connected to the PLC controller (7) via a terminal.

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