A heat treatment device for MIM parts of an automotive injection system

Abstract

This utility model relates to the field of heat treatment technology for automotive parts, and specifically discloses a heat treatment device for MIM parts of an automotive injection system. The device includes a top cover at the top of the outer shell, an inner cavity fixedly installed inside the shell, a resistance wire for heating the parts installed between the inner cavity and the outer shell, a mixing chamber fixedly installed on the top cover, gas guide pipes for injecting gas evenly installed on the mixing chamber, a spiral channel for mixing the gas inside the gas guide pipes, a graphite sealing gasket for sealing fixedly installed on the top cover, and a tray fixedly installed on the top cover. A gas supply mechanism delivers protective gas and reactive gas along the gas guide pipes into the mixing chamber, and then discharges them into the inner cavity through an opening in the center of the mixing chamber. This process protects the heated parts and performs carburizing and nitriding treatments, effectively and reliably preventing oxidation of the parts and improving the quality of the heat treatment.

Description

Technical Field

[0001] This utility model relates to the field of heat treatment technology for parts, and in particular to a heat treatment device for MIM parts of an automotive injection system. Background Technology

[0002] In the manufacturing of MIM (Metal Injection Molding) parts for automotive injection systems, high-quality heat treatment is a crucial factor determining their performance. In practical applications, heat treatment equipment for MIM parts in automotive injection systems typically has the following structure:

[0003] 1. Heating mechanism: When current passes through the resistive element, the resistive element generates heat, and the heating of the parts is achieved through heat transfer;

[0004] 2. Temperature control mechanism: To achieve precise temperature control, the device is equipped with a variety of temperature control mechanisms. The temperature sensor is a key component of the temperature control mechanism, which monitors the temperature of the parts and the furnace environment in real time and converts the temperature signal into an electrical signal to feed back to the control system.

[0005] 3. Atmosphere control mechanism: This structure is used to precisely control the atmosphere inside the furnace during the heat treatment process. Inert protective gases such as nitrogen and argon are introduced into the furnace through gas supply pipes to prevent oxidation of parts. For processes such as carburizing and nitriding, corresponding reaction gases also need to be introduced.

[0006] In existing heat treatment processes, metals readily react with oxygen in the air at high temperatures to form metal oxides during heat treatment. For MIM parts in automotive injection systems, such as fuel injectors and fuel pumps, oxidation forms an oxide film on the surface of the parts, altering their surface roughness and chemical composition. This not only affects the appearance of the parts but, more importantly, reduces their dimensional accuracy, causing changes in the fit clearance and affecting the normal operation of the injection system. Utility Model Content

[0007] To address the shortcomings of existing technologies, this utility model provides a heat treatment device for MIM parts of automotive injection systems. This device solves the problem that in existing heat treatment mechanisms, metals readily react with oxygen in the air at high temperatures to form metal oxides. For MIM parts of automotive injection systems, such as fuel injectors and fuel pumps, oxidation forms an oxide film on the part surface, altering the surface roughness and chemical composition. This not only affects the appearance of the parts but, more importantly, reduces their dimensional accuracy, changes the fit clearance, and affects the normal operation of the injection system.

[0008] To achieve the above objectives, this utility model provides the following technical solution:

[0009] A heat treatment device for MIM parts of an automotive injection system includes a housing, a top cover at the top of the housing, an inner cavity fixedly installed inside the housing, a resistance wire for heating the parts installed between the inner cavity and the housing, a mixing chamber fixedly installed on the top cover, a gas guide pipe for injecting gas evenly installed on the mixing chamber, a spiral channel for mixing gas provided inside the gas guide pipe, a graphite sealing gasket for sealing fixedly installed on the top cover, and a tray fixedly installed on the top cover.

[0010] Preferably, electric actuators are symmetrically fixedly mounted on the outer casing.

[0011] Preferably, the output shaft of the electric actuator is fixedly connected to the top cover.

[0012] Preferably, a mirrored reflective sleeve is fixedly installed on the inner side wall of the outer casing.

[0013] Preferably, a support frame is fixedly installed at the bottom of the outer casing.

[0014] Preferably, an infrared temperature sensor for measuring temperature is fixedly installed on the support frame.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. When the electric actuator pulls the top cover back to its original position, the graphite sealing gasket on the top cover fits against the inner bore, creating a relatively sealed environment inside the inner bore. Then, the resistance wire is energized and heats up. The heat generated by the resistance wire passes through the inner bore to heat the parts. During the heating process, the gas supply mechanism sends protective gas and reactive gas into the mixing chamber along the gas guide pipe. After entering the mixing chamber, the gas moves along the spiral channel. During this process, the gases collide and diffuse with each other, allowing the different gases to mix evenly. Then, the gas is discharged into the inner bore through the opening in the center of the mixing chamber, protecting the heated parts and performing carburizing and nitriding treatments. The even mixing of all gases before being discharged into the inner bore ensures a more uniform distribution of gases inside the inner bore. During heating, the inner bore has good permeability to the heat radiation generated by the resistance wire, effectively transferring heat to the parts without causing chemical reactions between the inner bore and the protective gas and reactive gas, thus avoiding atmospheric pollution. At the same time, it also prevents the reactive gas from affecting the outer shell and the resistance wire, effectively and reliably preventing oxidation of the parts and achieving the effect of improving the heat treatment quality of the parts.

[0017] Second, during the cooling process, the infrared temperature sensor monitors the internal temperature through the inner cavity from the bottom and sends the data to the control system to ensure that the cooling rate is maintained within the required range, thus achieving the effect of temperature control. Attached Figure Description

[0018] The above description is only an overview of the technical solution of this utility model. In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, the preferred embodiments of this utility model are described in detail below with reference to the accompanying drawings.

[0019] Figure 1 This is a structural diagram of the top cover of this utility model;

[0020] Figure 2 This is a structural diagram of the support frame of this utility model;

[0021] Figure 3 This is a cross-sectional structural diagram of the present invention;

[0022] Figure 4 This is a cross-sectional view of the inner bore of this utility model;

[0023] Figure 5 This is a cross-sectional view of the mixing box of this utility model;

[0024] Figure 6 This is an exploded structural diagram of the present invention.

[0025] Legend: 1. Outer shell; 2. Top cover; 3. Resistance wire; 4. Inner chamber; 5. Mixing box; 6. Air guide pipe; 7. Spiral channel; 8. Graphite sealing gasket; 9. Electric push rod; 11. Mirror reflector sleeve; 12. Support frame; 13. Infrared temperature sensor; 14. Tray. Detailed Implementation

[0026] This application provides a heat treatment device for MIM parts in an automotive injection system. It effectively solves the problem of existing heat treatment mechanisms where, during heat treatment, metal readily reacts with oxygen in the air at high temperatures to form metal oxides. For MIM parts in automotive injection systems, such as fuel injectors and fuel pumps, oxidation forms an oxide film on the part surface, altering the surface roughness and chemical composition. This not only affects the appearance of the part but, more importantly, reduces its dimensional accuracy, changes the fit clearance, and affects the normal operation of the injection system. The device addresses this issue by having an electric push rod pull the top cover back to its original position, causing the graphite sealing gasket on the top cover to fit against the inner bore, creating a relatively sealed environment. Then, a resistance wire is energized and heats up, passing through the inner bore to heat the part. During heating, a gas supply mechanism delivers protective gas and reactive gas along the gas guide pipe into the mixing chamber. After entering the mixing chamber, the gas moves along a spiral channel, constantly colliding and diffusing to ensure uniform mixing. The mixture is then discharged from the mixing chamber. The central opening leads into the inner bore, protecting and carburizing / nitriding the heated parts. The gases are mixed evenly before being discharged into the inner bore, ensuring a more uniform gas distribution. During heating, the inner bore has good permeability to the heat radiation generated by the resistance wire, effectively transferring heat to the parts without chemically reacting with the protective or reactive gases, thus preventing atmospheric contamination. It also prevents the reactive gases from affecting the outer shell and resistance wire, effectively and reliably preventing oxidation of the parts and improving the quality of heat treatment. During cooling, an infrared temperature sensor monitors the internal temperature from the bottom through the inner bore and sends the data to the control system, ensuring the cooling rate remains within the required range, thus facilitating temperature control. Example

[0027] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the technical solution in this application effectively solves the problem of existing heat treatment mechanisms. During heat treatment of parts, metals readily react with oxygen in the air at high temperatures to generate metal oxides. For automotive injection system MIM parts, such as fuel injectors and fuel pumps, oxidation forms an oxide film on the part surface, altering the surface roughness and chemical composition. This not only affects the appearance of the parts but, more importantly, reduces their dimensional accuracy, causing changes in the fit clearance and affecting the normal operation of the injection system. The overall approach is as follows:

[0028] To address the problems existing in the prior art, this utility model provides a heat treatment device for MIM parts of an automotive injection system, including a housing 1, a top cover 2 at the top of the housing 1, an inner cavity 4 fixedly installed inside the housing 1, a resistance wire 3 for heating the parts installed between the inner cavity 4 and the housing 1, and a mixing box 5 fixedly installed on the top cover 2.

[0029] Gas guide pipes 6 for injecting gas are evenly installed on the mixing box 5. The gas guide pipes 6 have spiral channels 7 for mixing gas inside. Graphite sealing gaskets 8 for sealing are fixedly installed on the top cover 2. A tray 14 is fixedly installed on the top cover 2. Electric push rods 9 are symmetrically fixedly installed on the outer shell 1.

[0030] The output shaft of the electric actuator 9 is fixedly connected to the top cover 2. A mirror reflector sleeve 11 is fixedly installed on the inner side wall of the outer shell 1. A support frame 12 is fixedly installed at the bottom of the outer shell 1. An infrared temperature sensor 13 for measuring temperature is fixedly installed on the support frame 12.

[0031] Outer shell 1: It is made of stainless steel and rock wool composite, serving as the external protection of the heat treatment device and preventing internal heat loss. A mirror reflector sleeve 11 is fixedly installed on the inner wall, and a support frame 12 is fixedly installed at the bottom.

[0032] Top cover 2: Made of quartz, it is located at the top of the outer shell 1 and is fixedly connected to the output shaft of the electric push rod 9. It can move up and down under the action of the electric push rod 9. The mixing box 5 and the graphite sealing gasket 8 are fixedly installed on it. By moving, the graphite sealing gasket 8 is made to fit with the inner cavity 4, which helps to form a relatively sealed environment inside the inner cavity 4 and meet the requirements of heat treatment for atmosphere control.

[0033] Resistance wire 3: Installed between the inner cavity 4 and the outer shell 1, it heats up when energized, and the heat generated passes through the inner cavity 4 to heat the parts placed on the tray 14, which is the heat source for the heat treatment of the parts;

[0034] The inner cavity 4 is made of quartz and is fixedly installed inside the outer shell 1. It has good permeability to the heat radiation generated by the resistance wire 3 and can effectively transfer heat to the parts. It does not react chemically with the protective gas or the reactive gas, thus avoiding pollution of the atmosphere. At the same time, it prevents the reactive gas from affecting the outer shell 1 and the resistance wire 3, providing a stable and reliable environment for the heat treatment of the parts.

[0035] Mixing box 5: It is fixedly installed on the top cover 2, and has evenly installed air guide pipes 6. After the gas enters the mixing box 5 through the air guide pipes 6, it is guided by the internal structure of the mixing box 5 and discharged into the inner cavity 4 through the central opening, so that the mixed gas can be evenly distributed in the inner cavity 4, providing protection for the parts and performing carburizing and nitriding treatments.

[0036] Gas guide pipe 6: Evenly installed on the mixing box 5, and connected to the gas supply mechanism of different gases respectively, used to introduce protective gas, reaction gas, etc. into the mixing box 5, and is the channel for gas to enter the device;

[0037] Spiral channel 7: Located inside the gas guide pipe 6, it guides the movement of gas entering the mixing box 5, so that the gas will continuously collide and diffuse with each other during the movement, thereby achieving uniform mixing of different gases and ensuring the consistency of the atmosphere composition in the furnace.

[0038] Graphite sealing gasket 8: It is fixedly installed on the top cover 2. When the top cover 2 is reset under the action of the electric push rod 9, the graphite sealing gasket 8 fits with the inner cavity 4, so that the inner cavity 4 forms a relatively sealed environment, preventing outside air from entering and interfering with the atmosphere inside the furnace, and ensuring the stability of the atmosphere during the heat treatment process.

[0039] Electric actuator 9: Symmetrically fixedly installed on the outer shell 1, its output shaft is fixedly connected to the top cover 2. By pushing and pulling the top cover 2 upward, the top cover 2 can be moved up and down, thereby controlling the contact and separation of the graphite sealing gasket 8 and the inner cavity 4, completing the placement of parts before heat treatment and the formation of a sealed environment during heat treatment.

[0040] Mirror reflector sleeve 11: It is fixedly installed on the inner wall of the outer shell 1, located between the outer shell 1 and the resistance wire 3, and is used to reflect the heat radiation diffused outward from the resistance wire 3 to reduce heat loss;

[0041] Support frame 12: Made of quartz, it is fixedly installed at the bottom of the outer casing 1 to provide support for the device;

[0042] Infrared temperature sensor 13: It is fixedly installed on the support frame 12. During the cooling process, it monitors the internal temperature of the device through the inner cavity 4 from the bottom and sends the data to the control system to help the control system ensure that the cooling rate is maintained within the required range and achieve effective temperature control.

[0043] Tray 14 is made of quartz and is used to place parts that need to be processed.

[0044] Working principle:

[0045] The first step involves connecting the resistance wire 3, the electric actuator 9, and the infrared temperature sensor 13 to the control system during installation. Four gas supply pipes 6 are connected to different gas supply mechanisms (such as protective gases like nitrogen and argon, and reactive gases like carbon and nitrogen). During use, the electric actuator 9 pushes the top cover 2 upwards, exposing the tray 14. The parts requiring heat treatment are then placed on the tray 14. The electric actuator 9 then pulls the top cover 2 back to its original position, causing the graphite sealing gasket 8 on the top cover 2 to fit against the inner cavity 4, creating a relatively sealed environment inside the inner cavity 4. The resistance wire 3 is then energized and heats up, passing through the inner cavity 4 to heat the parts. During heating, the gas supply mechanism delivers the protective gas and reactive gas along the gas supply pipes 6 into the mixing chamber 5. The gases then enter the mixing chamber... The gas will move along the spiral channel 7 in the mixing chamber 5. During this process, the gases will continuously collide and diffuse with each other, so that the different gases can be mixed evenly. Then, the gas is discharged into the inner chamber 4 through the opening in the center of the mixing chamber 5 to protect the heated parts and perform carburizing and nitriding treatments. After the gases are mixed evenly, they are discharged into the inner chamber 4, which makes the distribution of gases inside the inner chamber 4 more uniform. During heating, the inner chamber 4 has good permeability to the heat radiation generated by the resistance wire 3, which can effectively transfer heat to the parts. At the same time, the inner chamber 4 will not chemically react with the protective gas and the reactive gas, thus avoiding pollution of the atmosphere. At the same time, it can also prevent the reactive gas from affecting the outer shell 1 and the resistance wire 3, effectively and reliably preventing the parts from oxidizing, thereby improving the heat treatment quality of the parts.

[0046] In the second step, the mirror reflector sleeve 11 is located between the resistance wire 3 and the outer shell 1, which can reflect the outward diffused heat radiation inward, thereby improving the heating efficiency. During the cooling process, the infrared temperature sensor 13 monitors the internal temperature through the inner cavity 4 from the bottom and sends the data to the control system to ensure that the cooling rate is maintained within the required range, thus achieving the effect of temperature control.

[0047] Finally, it should be noted that the above embodiments are merely examples for clearly illustrating the present invention and are not intended to limit the implementation. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. An automotive injection system MIM part heat treatment apparatus comprising a housing (1), characterized in that, The top of the outer shell (1) is provided with a top cover (2), the inner cavity (4) is fixedly installed inside the outer shell (1), a resistance wire (3) for heating parts is installed between the inner cavity (4) and the outer shell (1), a mixing box (5) is fixedly installed on the top cover (2), a gas guide pipe (6) for injecting gas is evenly installed on the mixing box (5), a spiral channel (7) for mixing gas is provided inside the gas guide pipe (6), a graphite sealing gasket (8) for sealing is fixedly installed on the top cover (2), and a tray (14) is fixedly installed on the top cover (2).

2. A heat treatment apparatus for MIM parts of an automotive injection system according to claim 1, characterized in that, Electric actuators (9) are symmetrically fixedly installed on the outer casing (1).

3. A heat treatment apparatus for MIM parts of an automotive injection system according to claim 2, characterized in that, The output shaft of the electric actuator (9) is fixedly connected to the top cover (2).

4. A heat treating apparatus for MIM parts of an automotive injection system as claimed in claim 1, wherein, A mirror reflector sleeve (11) is fixedly installed on the inner wall of the outer shell (1).

5. A heat treating apparatus for MIM parts of an automotive injection system as claimed in claim 1, wherein, A support frame (12) is fixedly installed at the bottom of the outer shell (1).

6. A heat treatment apparatus for MIM parts of an automotive injection system according to claim 5, characterized in that, An infrared temperature sensor (13) for measuring temperature is fixedly installed on the support frame (12).

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