A vacuum furnace

Abstract

The utility model discloses a vacuum furnace, including the furnace shell, its at least one end is equipped with the furnace door, install the tubular main heating net in the furnace shell, the main heating net faces the furnace door side and presents the open mouth shape, the furnace door inboard is equipped with the auxiliary heating net, the auxiliary heating net is when the furnace door is closed and blocks the end of main heating net open mouth, thereby makes main heating net and auxiliary heating net common composition cage -like structure. Through setting up the auxiliary heating net in the furnace door inboard, the furnace door is closed and blocks the end of main heating net open mouth and forms cage -like structure, can effectively reduce the heat loss of the area close to the furnace door. Compared with prior art, the structure can make the heat distribution in the hearth more uniform, effectively improve the temperature inconsistency problem caused by the heat exchange at the furnace door, and further significantly improve the heat treatment quality of the workpiece, ensure that all parts of the workpiece can be treated at the same ideal temperature.

Description

Technical Field

[0001] This utility model mainly relates to the field of heat treatment furnace technology, and in particular to a vacuum furnace. Background Technology

[0002] A vacuum furnace is a heat treatment device that uses a vacuum system to remove some materials from the furnace chamber, reducing the pressure inside to less than one atmosphere, thus creating a vacuum state within the furnace chamber. A vacuum furnace generally consists of a furnace chamber, heating elements, a temperature control system, a vacuum system, a water cooling system, and a sealed furnace shell. Based on the heating method, it can be classified into vacuum resistance furnaces, vacuum induction furnaces, vacuum arc furnaces, vacuum arc furnaces, electron beam furnaces (also known as electron bombardment furnaces), and plasma furnaces. Vacuum furnaces are widely used in high-temperature vacuum sintering, annealing, tempering, and aging treatment of ceramic materials, ceramic-metal composites, refractory metals, and alloys, as well as vacuum brazing of alloy cutting tools and superhard materials.

[0003] Existing vacuum furnaces are mostly horizontally arranged cylindrical structures with furnace doors at both ends for workpiece entry and exit. Inside the furnace shell, a cylindrical heating mesh consisting of several heaters (such as heating rods) is installed along the length of the furnace shell. To facilitate workpiece entry and exit, the two ends of the heating mesh facing the furnace doors are open. During heat treatment, the cylindrical heating mesh can only radiate heat into the furnace chamber from four directions: top, bottom, front, and back. The areas near the furnace doors, located at the left and right ends, are more prone to heat loss due to heat exchange with the outside environment through the furnace doors. Therefore, the temperature uniformity within the furnace chamber is poor, which in turn affects the heat treatment quality of the workpiece. Utility Model Content

[0004] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a vacuum furnace.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A vacuum furnace includes a furnace shell with a furnace door at at least one end. A cylindrical main heating mesh is installed inside the furnace shell, with the main heating mesh open towards the furnace door. A secondary heating mesh is located inside the furnace door, and when the furnace door is closed, the secondary heating mesh seals the open end of the main heating mesh, thus forming a cage-like structure together. By setting the secondary heating mesh inside the furnace door and sealing the open end of the main heating mesh to form a cage-like structure when the furnace door is closed, heat loss near the furnace door area can be effectively reduced. Compared with existing technologies, this structure allows for a more uniform heat distribution within the furnace chamber, effectively improving the temperature inconsistency caused by heat exchange at the furnace door, thereby significantly improving the heat treatment quality of the workpiece and ensuring that all parts of the workpiece are processed at the same ideal temperature.

[0007] As a further improvement to the above technical solution:

[0008] The furnace shell has a cylindrical structure with a furnace door at each end. This dual-end design greatly improves the convenience of workpieces entering and exiting the furnace, increasing work efficiency. Furthermore, in conjunction with the auxiliary heating mesh, it effectively compensates for heat loss at both furnace doors, further ensuring the uniformity of the overall temperature within the furnace. Regardless of which end the workpiece enters or exits from, heat treatment can be performed in a stable and uniform temperature environment, overcoming the problem of poor heat control at the other furnace door area when only one end is used for material entry or exit in existing technologies.

[0009] The vacuum furnace also includes a temperature control device for adjusting the heating power of the main and auxiliary heating grids, as well as thermocouples and infrared thermometers for acquiring temperature information within the furnace chamber. The main heating grid, auxiliary heating grid, thermocouples, and infrared thermometers are electrically connected to the temperature control device. The combined use of the temperature control device with the thermocouples and the infrared thermometer enables precise monitoring and control of the furnace chamber temperature. The thermocouples and infrared thermometers acquire real-time temperature information within the furnace chamber and feed it back to the temperature control device, which then adjusts the heating power of the main and auxiliary heating grids accordingly. When a temperature deviation is detected within the furnace chamber, the device reacts quickly and precisely adjusts the heating power to ensure a stable and uniform temperature within the furnace chamber. This provides reliable temperature assurance for high-quality heat treatment of workpieces and solves the problem of poor temperature consistency caused by the inability to precisely control furnace temperature in existing technologies.

[0010] The main heating grid includes several main heating rods; the furnace shell has a cylindrical structure, and the furnace chamber is divided into several temperature zones along the length of the furnace shell. The main heating rods located in the same temperature zone are electrically connected to the same temperature control device. Dividing the furnace chamber into multiple temperature zones and independently controlling the temperature of the main heating rods in each zone allows for flexible adjustment of the heating power according to the actual needs of different temperature zones. The heat distribution in different zones can be customized according to the heat treatment requirements of the workpiece at different locations, avoiding excessively high or low temperatures in some areas due to uniform heating. This further improves the controllability and uniformity of the temperature within the furnace chamber, meets the diverse temperature gradient requirements of different workpieces at different heat treatment stages, and enhances the applicability and processing effect of the vacuum furnace.

[0011] The auxiliary heating network includes several auxiliary heating rods; the auxiliary heating rods on the same furnace door are electrically connected to the same temperature control device. The connection between the auxiliary heating rods on the same furnace door and the same temperature control device allows the auxiliary heating network at the furnace door to precisely adjust its heating power according to the actual temperature near the furnace door. When the temperature drops in the area near the furnace door due to heat exchange, the auxiliary heating rods can respond quickly and replenish heat in a timely manner, ensuring that the temperature in the furnace door area remains consistent with other areas inside the furnace. This effectively prevents uneven temperature distribution within the overall furnace due to abnormal temperatures at the furnace door, thus improving the overall temperature stability and heat treatment quality of the vacuum furnace.

[0012] The main heating rod located in the end temperature zone and the auxiliary heating rod on the corresponding furnace door are connected to the same temperature control device. This connection method allows for closer coordination between the heating systems in the end temperature zone and the corresponding furnace door. When the temperature in the end temperature zone changes, the auxiliary heating rod connected to it on the furnace door can adjust its power synchronously, and vice versa. Through this linkage control, the heat distribution in the end temperature zone and the area near the furnace door can be better balanced, avoiding temperature deviations caused by the special heat exchange conditions in this area. This further ensures the temperature uniformity at both ends of the furnace chamber, guarantees the temperature consistency of the entire furnace chamber, and improves the heat treatment quality of the workpiece at both ends of the furnace chamber.

[0013] Each temperature zone is equipped with at least one thermocouple and one infrared thermometer. Each zone is equipped with both a thermocouple and an infrared thermometer, enabling independent and precise temperature monitoring. Compared to installing thermocouples and infrared thermometers only in a few locations, this comprehensive temperature monitoring method can more timely and accurately detect temperature changes within each zone, providing more detailed temperature information to the temperature control device. This allows for precise control of the heating power in each zone, ensuring that the temperature in each zone remains within the set range. This further improves the uniformity and stability of the temperature within the furnace, providing strong support for high-quality workpiece heat treatment.

[0014] The main heating grid, the auxiliary heating grid, the thermocouple, and the infrared thermometer, all located within the same temperature zone, are electrically connected to the same temperature control device. Within the same temperature zone, connecting these components to the same temperature control device forms a highly efficient closed-loop temperature control system. The thermocouples and infrared thermometer provide real-time temperature feedback within the zone, and the temperature control device adjusts the power of both the main and auxiliary heating grids based on this information, ensuring precise heat replenishment and balance within the zone. This close collaborative control mechanism significantly improves the temperature control accuracy and response speed within the zone, ensuring high temperature uniformity in each zone and comprehensively enhancing the temperature control performance of the vacuum furnace and the heat treatment quality of the workpiece. Attached Figure Description

[0015] Figure 1This is a schematic diagram of the structure of a vacuum furnace;

[0016] Figure 2 This is a schematic diagram of the main heating mesh structure;

[0017] Figure 3 This is a schematic diagram of the auxiliary heating mesh.

[0018] The labels in the diagram represent: 1. Furnace shell; 2. Furnace door; 3. Main heating mesh; 31. Main heating rod; 4. Auxiliary heating mesh; 41. Auxiliary heating rod; 5. Thermocouple; 6. Infrared thermometer. Detailed Implementation

[0019] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] Example

[0021] like Figures 1 to 3 As shown in the figure, this embodiment provides a vacuum furnace, the structure of which is as follows:

[0022] The furnace shell 1 adopts a cylindrical structure. This design facilitates the formation of a stable heating space within the furnace chamber and makes it easy to install and maintain the internal heating and temperature control components. A furnace door 2 is located at each end. In actual operation, when workpieces need to be placed in the furnace for heat treatment, they can be conveniently fed in from either door, greatly improving work efficiency. For example, when processing workpieces of different specifications in batches, the furnace door can be flexibly selected according to the placement and order of workpiece entry and exit, reducing the time lost in workpiece handling and furnace operations.

[0023] A cylindrical main heating mesh 3 is installed inside the furnace shell 1. The main heating mesh 3 is open on the side facing the furnace door 2 to facilitate the entry and exit of workpieces from the furnace chamber. The main heating mesh 3 consists of several main heating rods 31, which are distributed along the length of the furnace shell 1. The furnace chamber is divided into several temperature zones along the length of the furnace shell 1. The main heating rods 31 located in the same temperature zone are electrically connected to the same temperature control device. For example, the furnace chamber is divided into three temperature zones: the front temperature zone, the middle temperature zone, and the rear temperature zone. The main heating rods 31 in each temperature zone work independently under the control of the temperature control device according to the set temperature and process requirements of their respective temperature zones. When annealing a certain alloy material, the main heating rod 31 in the middle temperature zone can maintain a relatively high and stable power output under the precise control of the temperature control device according to the annealing temperature curve of the material, so as to ensure that the material in this area reaches the ideal annealing temperature; while the main heating rods 31 in the front and rear temperature zones maintain an appropriate power under the adjustment of the temperature control device according to the heat transfer characteristics and temperature gradient requirements, so as to form a reasonable temperature distribution in the entire furnace and meet the strict requirements of temperature uniformity in the alloy material annealing process.

[0024] A secondary heating mesh 4 is provided inside the furnace door 2. When the furnace door 2 is closed, the secondary heating mesh 4 seals the end opening of the main heating mesh 3, thus forming a cage-like structure together with the main heating mesh 3. The secondary heating mesh 4 includes several secondary heating rods 41, and the secondary heating rods 41 on the same furnace door 2 are electrically connected to the same temperature control device. The main heating rods 31 located in the end temperature zone are connected to the same temperature control device as the corresponding secondary heating rods 41 on the furnace door 2. In the actual heating process, the secondary heating mesh 4 starts working after the furnace door 2 is closed. Taking the processing of ceramic-metal composite materials as an example, during the high-temperature vacuum sintering process, the temperature near the furnace door tends to drop due to heat exchange with the outside environment. At this time, by adjusting the power of the secondary heating rods 41 through the temperature control device, heat is replenished in time, so that the temperature of the furnace door area is consistent with that of other areas inside the furnace chamber. This effectively avoids uneven temperature distribution in the overall furnace chamber caused by abnormal temperature at the furnace door, ensuring that the ceramic-metal composite materials are sintered in a uniform and stable temperature environment, thus improving the quality and consistency of the product.

[0025] The vacuum furnace also includes a temperature control device for adjusting the heating power of the main heating network 3 and the auxiliary heating network 4, as well as thermocouples 5 and infrared thermometers 6 for acquiring temperature information inside the furnace. The main heating network 3, auxiliary heating network 4, thermocouples 5, and infrared thermometers 6 are electrically connected to the temperature control device, and each temperature zone has at least one thermocouple 5 and one infrared thermometer 6. The main heating network 3, auxiliary heating network 4, thermocouples 5, and infrared thermometers 6 located in the same temperature zone are electrically connected to the same temperature control device. During vacuum tempering of refractory metals, the thermocouples 5 and infrared thermometers 6 monitor the temperature of each temperature zone in real time and feed the temperature information back to the temperature control device. If, during the heating phase, the temperature of a certain temperature zone rises too quickly or fails to reach the predetermined heating curve, the temperature control device will immediately adjust the heating power of the corresponding main heating network 3 and auxiliary heating network 4 to restore the temperature to normal. During the heat preservation stage, thermocouple 5 and infrared thermometer 6 continuously monitor temperature fluctuations to ensure that the temperature in each temperature zone remains stable within the range required by the process, thus guaranteeing the quality and performance of the tempering treatment of refractory metals.

[0026] In some embodiments, the thermocouple 5 is used in conjunction with the infrared thermometer 6. The thermocouple 5, which is installed through the furnace shell 1, has a telescopic function; it can extend into the furnace chamber to measure the temperature inside, or it can extend out of the furnace shell 1 after temperature measurement stops. For example, when heat-treating a workpiece in a vacuum furnace, when the furnace temperature does not exceed 900°C, the thermocouple 5 extends into the furnace chamber to measure the temperature, and the infrared thermometer 6 is in the off state. When the furnace temperature exceeds 900°C, the infrared thermometer 6 is activated, and the thermocouple 5 stops measuring the temperature and retracts out of the furnace shell 1. In the low-temperature range (not exceeding 900°C), the thermocouple extends into the furnace chamber to directly contact the workpiece or environment for temperature measurement, which can obtain relatively accurate temperature data. Because the thermocouple's performance is stable at low temperatures and is less affected by interference factors, it can accurately reflect the actual temperature situation. When the temperature exceeds 900°C, the thermocouple retracts, and the infrared thermometer is activated. Infrared thermometers offer the advantage of non-contact temperature measurement in high-temperature environments, avoiding the measurement errors that thermocouples may cause due to material properties changes or oxidation at high temperatures. This ensures accurate and reliable temperature measurements across different temperature ranges, providing strong support for precise control of heat treatment processes. Furthermore, in the low-temperature range (not exceeding 900℃), the thermocouple is inserted into the furnace to directly contact the workpiece or environment for temperature measurement, obtaining relatively accurate temperature data. Because thermocouples are stable at low temperatures and are less susceptible to interference, they accurately reflect the actual temperature. When the temperature exceeds 900℃, the thermocouple retracts, at which point the infrared thermometer is activated. This combination of methods allows for automatic switching of the temperature measuring instrument based on changes in furnace temperature, eliminating the need for manual intervention. Once the furnace temperature reaches the set threshold of 900℃, the system automatically controls the thermocouple to retract and activates the infrared thermometer. This automated temperature measurement method not only improves production efficiency but also avoids the influence of human factors on the temperature measurement process, enhancing the intelligence and automation level of the entire heat treatment system and helping to achieve more efficient and stable production process control.

[0027] As can be seen from the above embodiments, the vacuum furnace of this utility model, through its unique structural design and system configuration, effectively solves the problems of poor temperature uniformity, large heat loss and low processing efficiency of existing vacuum furnaces. It shows significant advantages in the heat treatment of various materials and can meet the industrial production demand for high-quality and high-efficiency vacuum heat treatment equipment.

[0028] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make many possible variations and modifications to the present invention, or modify it into equivalent embodiments, without departing from the scope of the present invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention, without departing from the content of the present invention, should fall within the protection scope of the present invention.

Claims

1. A vacuum furnace, comprising a furnace shell (1) having a furnace door (2) at at least one end, wherein a cylindrical main heating mesh (3) is installed inside the furnace shell (1), the main heating mesh (3) being open on the side facing the furnace door (2), characterized in that: The furnace door (2) is provided with an auxiliary heating mesh (4) inside. When the furnace door (2) is closed, the auxiliary heating mesh (4) blocks the end opening of the main heating mesh (3), so that the main heating mesh (3) and the auxiliary heating mesh (4) together form a cage structure.

2. The vacuum furnace according to claim 1, characterized in that: The furnace shell (1) has a cylindrical structure, with a furnace door (2) at each end.

3. The vacuum furnace according to claim 1, characterized in that: The vacuum furnace also includes a temperature control device for adjusting the heating power of the main heating grid (3) and the auxiliary heating grid (4), as well as a thermocouple (5) and an infrared thermometer (6) for obtaining temperature information inside the furnace; the main heating grid (3), the auxiliary heating grid (4), the thermocouple (5) and the infrared thermometer (6) are electrically connected to the temperature control device respectively.

4. The vacuum furnace according to claim 3, characterized in that: The main heating grid (3) includes several main heating rods (31); the furnace shell (1) has a cylindrical structure, and the furnace chamber is divided into several temperature zones along the length of the furnace shell (1). The main heating rods (31) located in the same temperature zone are electrically connected to the same temperature control device.

5. The vacuum furnace according to claim 4, characterized in that: The auxiliary heating grid (4) includes several auxiliary heating rods (41); the auxiliary heating rods (41) on the same furnace door (2) are electrically connected to the same temperature control device.

6. The vacuum furnace according to claim 5, characterized in that: The main heating rod (31) located in the end temperature zone and the auxiliary heating rod (41) on the corresponding furnace door (2) are connected to the same temperature control device.

7. The vacuum furnace according to claim 5, characterized in that: Each temperature zone shall have at least one thermocouple (5) and one infrared thermometer (6).

8. The vacuum furnace according to claim 7, characterized in that: The main heating grid (3), the auxiliary heating grid (4), the thermocouple (5), and the infrared thermometer (6), which are located in the same temperature zone, are electrically connected to the same temperature control device.

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