A detachable heating device and heater for hot runner nozzles

Abstract

The utility model discloses a detachable heating device and heater for hot runner nozzle belongs to injection molding equipment field. The heating device, include: heating unit and electric heating element, electric heating element is installed in heating unit, heating unit is set up in the nozzle, is set up with at least one longitudinal slot on heating unit, and longitudinal slot extends to the predetermined area arrangement from one end of heating unit to the other end, and one end of longitudinal slot is the open end, and the other end is the closed end, and the closed end forms the bridge body. The utility model discloses through the open end of longitudinal slot can be through the tool and is opened, and the temporary expansion heating unit inner diameter, and the quick solution and the adhesion of nozzle, do not need to forcibly split, reduce the risk of component damage, through the closed end of longitudinal slot and form the bridge body, guarantee the contact area of heating unit and nozzle, be favorable to temperature distribution uniform.

Description

Technical Field

[0001] In the field of injection molding equipment technology, this invention specifically relates to a detachable heating device and heater for hot runner nozzles, which is suitable for temperature control and maintenance disassembly of hot runner nozzles in injection molding machines. Background Technology

[0002] In injection molding, hot runner nozzles need to maintain the fluidity of the melt (such as plastic raw materials) through a heating device, and uniform temperature distribution is required to ensure the quality of the molded parts. Existing hot runner nozzle heating devices have the following problems: 1. Easily damaged during disassembly and assembly: After prolonged exposure to heat, molten residue or materials may seep into the gap between the heating device and the hot runner nozzle, forming an adhesive bond. During maintenance, it is necessary to forcibly disassemble the parts, which can easily damage them. 2. Uneven temperature control: If the heating unit has a through-type longitudinal groove, it will reduce the contact area with the nozzle, resulting in insufficient local heat transfer and large temperature fluctuations in the nozzle. Therefore, there is an urgent need for a heating device that is not easily damaged during disassembly and assembly and has uniform temperature control, in order to solve the pain points of existing technologies. Utility Model Content

[0003] Purpose of the utility model: This utility model aims to solve the problems of "easy damage during disassembly and assembly and uneven temperature" in existing hot runner nozzle heating devices, and to provide a structurally optimized detachable heating device and matching heater.

[0004] The technical solution of this utility model is: a detachable heating device for a hot runner nozzle, comprising: a heating unit and an electric heating element, wherein the electric heating element is installed on the heating unit, and the heating unit is sleeved on the nozzle.

[0005] The heating unit has at least one longitudinal groove.

[0006] The longitudinal groove extends from one end of the heating unit to the other end into a predetermined area, such that one end of the longitudinal groove is an open end and the other end is a closed end, with the closed end forming a bridge.

[0007] In a further embodiment, the heating unit is provided with at least two longitudinal slots.

[0008] At least one of the longitudinal grooves extends from the first end face of the heating unit to the second end face.

[0009] At least one of the longitudinal grooves extends from the second end face of the heating unit to the first end face, so that the inner diameter of both ends of the heating unit can be temporarily enlarged, further facilitating the assembly and disassembly of the heating unit.

[0010] In a further embodiment, the heating unit is provided with at least two longitudinal slots.

[0011] The longitudinal grooves are evenly distributed along the circumference of the heating unit. The even distribution of multiple longitudinal grooves enhances the structural strength of the heating unit and extends its service life.

[0012] In a further embodiment, the longitudinal groove is inclined to prevent the thermocouple from getting stuck.

[0013] In a further embodiment, the length of the longitudinal groove is 85% to 90% of the total length of the heating unit.

[0014] In a further embodiment, the outer surface of the heating unit is provided with a spiral channel, the spiral channel having a bottom surface and two side walls, and having at least one intersecting longitudinal groove.

[0015] The electric heating element is installed in the spiral channel and is in contact with the bottom surface and at least one side wall of the spiral channel, ensuring that the heat generated by the heating wire is efficiently transferred to the hot runner nozzle through the heating unit.

[0016] In a further embodiment, the pitch of the spiral channels at both ends of the heating unit is smaller than that of the spiral channels in the middle region. The closed end of the longitudinal groove forms a bridge body to ensure the contact area between the heating unit and the nozzle at both ends. Combined with the variable pitch design of the spiral channels, heat loss at both ends of the nozzle can be specifically compensated, further ensuring uniform temperature distribution.

[0017] In a further embodiment, the electric heating element includes a heating wire and a housing.

[0018] The heating wire is encapsulated in a housing, and the coefficient of expansion of the housing is lower than that of the heating unit. The housing of the electric heating element can limit the radial expansion of the heating unit caused by heating or external force, thereby further extending its service life.

[0019] A heater includes a thermocouple and a heating device, the heating device including an electric heating element, and the thermocouple and heating device being used to connect to an external control device.

[0020] The heating device is any of the heating devices described in the above embodiments.

[0021] The thermocouple is provided with a temperature detection end and a signal transmission line, and the heating device is provided with a mounting groove.

[0022] The temperature detection end passes through the mounting groove and engages with the nozzle. The temperature detection end and the signal transmission line are distributed at intervals with the longitudinal groove.

[0023] In a further embodiment, the heater includes a main thermocouple and redundant thermocouples.

[0024] The main thermocouple and redundant thermocouples are distributed at intervals along the circumference of the heating unit to avoid temperature detection failure due to the failure of a single thermocouple.

[0025] The advantages of this utility model are: easy disassembly and assembly: the opening end of the longitudinal groove can be opened with tools to temporarily expand the inner diameter of the heating unit, quickly dissolve the adhesion with the nozzle, and reduce the risk of component damage without the need for forced disassembly.

[0026] Uniform temperature: The closed end of the longitudinal groove forms a bridge, ensuring the contact area between the heating unit and the nozzle, which is conducive to uniform temperature distribution. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the assembly structure of the heater and hot runner nozzle of this utility model.

[0028] Figure 2 This is an exploded structural diagram of the heating unit, electric heating element, and thermocouple of this utility model. Figure 2 The diagram shows the exploded view of two parts of an electric heating element.

[0029] Figure 3 This is a detailed structural diagram of the longitudinal groove and thermocouple insertion hole of the heating unit of this utility model.

[0030] Figure 4 This is a cross-sectional structural diagram of the heating unit of this utility model.

[0031] Figure 5 yes Figure 4 A magnified view of part B.

[0032] The reference numerals in the figure are as follows: axis A, heating device 1, heating unit 1.1, open end 1.11, closed end 1.12, bridge body 1.13, mounting groove 1.14, bottom surface 1.15, side wall 1.16, electric heating element 1.2, thermocouple 2, nozzle 3. Detailed Implementation

[0033] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid confusion with the present invention.

[0034] This application discloses a structurally optimized detachable heating device and its matching heater, which solves the problems of "easy damage during disassembly and assembly and uneven temperature" in existing hot runner nozzle heating devices. Example 1:

[0035] The detachable heating device 1 for the hot runner nozzle 3 includes: a heating unit 1.1 and an electric heating element 1.2. The electric heating element 1.2 is installed on the heating unit 1.1. The heating unit 1.1 is sleeved on the nozzle 3. The way in which the heating unit 1.1 is detachably installed on the nozzle 3 is the prior art and will not be limited here.

[0036] The heating unit 1.1 is made of a metal material with good thermal conductivity, such as copper or aluminum alloy. The overall shape of the heating unit 1.1 is a slender hollow cylinder. It has an inner diameter that matches the outer surface of the hot runner nozzle 3, a length, an axis A, an inner surface that fits the outer surface of the nozzle 3, and an outer surface and wall thickness of 2~5mm to ensure thermal conductivity and structural strength.

[0037] like Figure 1-4 The heating unit 1.1 shown has at least one longitudinal groove.

[0038] The longitudinal groove extends from one end of the heating unit 1.1 to the other end to a predetermined area, with one end of the longitudinal groove being an open end 1.11 and the other end being a closed end 1.12. The closed end 1.12 forms a bridge body 1.13, which can limit the expansion of the inner diameter of the heating unit 1.1 at that end. The open end 1.11 can be opened by tools such as wedges or screwdrivers to temporarily expand the inner diameter of the heating unit 1.1 to dissolve the adhesion with the nozzle 3.

[0039] The longitudinal groove extends along axis A. In a preferred embodiment, the length is 85% to 90% of the total length of the heating unit 1.1 and does not penetrate the entire length of the heating unit 1.1.

[0040] like Figure 1-3 The heating unit 1.1 shown is provided with at least two longitudinal slots.

[0041] At least one longitudinal groove extends from the first end face of the heating unit 1.1 to the second end face.

[0042] At least one longitudinal groove extends from the second end face of the heating unit 1.1 to the first end face.

[0043] In a preferred embodiment, the heating unit 1.1 is provided with at least two longitudinal grooves, which are evenly distributed along the circumference of the heating unit 1.1. For example, the heating unit 1.1 is provided with four longitudinal grooves, which are evenly distributed along the circumference of the heating unit 1.1.

[0044] In a preferred embodiment, the longitudinal groove is inclined, for example, the angle between the longitudinal groove and the axis A is 3°~5°.

[0045] like Figure 2 The outer surface of the heating unit 1.1 shown is provided with a spiral channel, which has a bottom surface 1.15 and two side walls 1.16, and has at least one intersecting longitudinal groove.

[0046] The electric heating element 1.2 is installed in the spiral channel, such as... Figure 5 The electric heating element 1.2 shown is in contact with the bottom surface 1.15 and at least one sidewall 1.16 of the spiral channel.

[0047] In a preferred embodiment, the pitch of the spiral channels at both ends of the heating unit 1.1 is smaller than the pitch of the spiral channels in the middle region. For example, the pitch of the spiral channels at both ends of the heating unit 1.1 is 5~8mm, and the pitch of the spiral channels in the middle region of the heating unit 1.1 is 10~15mm.

[0048] In a preferred embodiment, the electric heating element 1.2 includes a heating wire and a housing. The heating wire is encapsulated in the housing, and the coefficient of thermal expansion of the housing is lower than that of the heating unit 1.1. For example, the heating wire is a nickel-chromium alloy wire, the housing is a metal housing such as a stainless steel shell, and the heating unit 1.1 is made of copper. Example 2:

[0049] The heater includes a thermocouple 2 and a heating device 1. The heating device 1 includes an electric heating element 1.2. The thermocouple 2 and the heating device 1 are used to connect to an external control device. The control device receives the temperature signal from the thermocouple 2, compares it with the target temperature, and adjusts the heating current of the electric heating element 1.2 to achieve precise temperature control.

[0050] Heating device 1 is the heating device 1 of the above embodiment 1.

[0051] Thermocouple 2 is equipped with a temperature detection end and a signal transmission line, and heating device 1 is equipped with a mounting groove 1.14.

[0052] The temperature sensing end passes through the mounting groove 1.14 and engages with the nozzle 3. The temperature sensing end and the signal transmission line are spaced apart from the longitudinal groove, so that the signal transmission line of the thermocouple 2 is arranged along the outer surface of the heating unit 1.1, avoiding the longitudinal groove, and ensuring that the tool does not touch the thermocouple 2 when it is being disassembled or installed.

[0053] In a preferred embodiment, the heater includes a main thermocouple 2 and redundant thermocouples 2.

[0054] The main thermocouple 2 and the redundant thermocouple 2 are distributed at intervals along the circumference of the heating unit 1.1, such as the redundant thermocouple 2 and the main thermocouple 2 being distributed at 180° along the circumference of the heating unit 1.1.

[0055] During assembly, the electric heating element 1.2 is pressed into the heating unit 1.1 and then fitted onto the nozzle 3 assembly. The thermocouple 2 is then inserted into the thermocouple 2 mounting hole on the nozzle 3 assembly through the groove of the slender heating unit 1.1.

[0056] During the heating process, the control device receives the temperature signal from thermocouple 2, compares it with the target temperature, and adjusts the heating current of electric heating element 1.2 to achieve precise temperature control.

[0057] When disassembly is required, first use tools such as wedges and screwdrivers to pry open the opening end 1.11 of the longitudinal groove, temporarily enlarging the inner diameter of the heating unit 1.1 to dissolve the adhesion with the nozzle 3, and then separate the heating unit 1.1 from the nozzle 3.

[0058] As described above, although the present invention has been shown and described with reference to specific preferred embodiments, it should not be construed as limiting the present invention itself. Various changes in form and detail may be made to the present invention without departing from the spirit and scope of the appended claims.

Claims

1. A detachable heating device for a hot runner nozzle, comprising: A heating unit and an electric heating element, wherein the electric heating element is installed in the heating unit and the heating unit is sleeved on the nozzle; The characteristic feature is that the heating unit has at least one longitudinal groove; The longitudinal groove extends from one end of the heating unit to the other end into a predetermined area, such that one end of the longitudinal groove is an open end and the other end is a closed end, with the closed end forming a bridge.

2. The detachable heating device for a hot runner nozzle according to claim 1, characterized in that, The heating unit is provided with at least two longitudinal slots; At least one of the longitudinal grooves extends from the first end face of the heating unit to the second end face; At least one of the longitudinal grooves extends from the second end face of the heating unit to the first end face.

3. The detachable heating device for a hot runner nozzle according to claim 1, characterized in that, The heating unit is provided with at least two longitudinal slots; The longitudinal grooves are evenly distributed along the circumference of the heating unit.

4. A detachable heating device for a hot runner nozzle according to any one of claims 1-3, characterized in that, The longitudinal groove is inclined.

5. A detachable heating device for a hot runner nozzle according to any one of claims 1-3, characterized in that, The length of the longitudinal groove is 85% to 90% of the total length of the heating unit.

6. The detachable heating device for a hot runner nozzle according to claim 1, characterized in that, The outer surface of the heating unit is provided with a spiral channel, which has a bottom surface and two side walls, and intersects with longitudinal grooves at least once; The electric heating element is installed in the spiral channel, and the electric heating element is in contact with the bottom surface and at least one side wall of the spiral channel.

7. A detachable heating device for a hot runner nozzle according to claim 6, characterized in that, The pitch of the spiral channels at both ends of the heating unit is smaller than the pitch of the spiral channels in the middle region.

8. A detachable heating device for a hot runner nozzle according to any one of claims 1-3, 6 or 7, characterized in that, The electric heating element includes: a heating wire and a housing; The heating wire is encapsulated within a housing, and the coefficient of expansion of the housing is lower than that of the heating unit.

9. A heater, comprising: A thermocouple and a heating device, the heating device including an electric heating element, the thermocouple and the heating device being used to connect to an external control device; The characteristic is that the heating device is the heating device according to any one of claims 1-3, 6 or 7; The thermocouple is provided with a temperature detection end and a signal transmission line, and the heating device is provided with a mounting groove; The temperature detection end passes through the mounting groove and engages with the nozzle. The temperature detection end and the signal transmission line are distributed at intervals with the longitudinal groove.

10. The heater according to claim 9, characterized in that, include: Main thermocouple and redundant thermocouple; The main thermocouple and redundant thermocouples are distributed at intervals along the circumference of the heating unit.

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