Miniature visual vacuum furnace

Abstract

The utility model discloses a miniature visual vacuum furnace which comprises a furnace body assembly, a furnace cover assembly and a furnace plate assembly, the furnace body assembly comprises a furnace shell, a furnace cavity for placing the furnace plate assembly is arranged in the furnace shell, a lower glass assembly corresponding to the furnace plate assembly is embedded in the bottom wall of the furnace shell, an electrode and a thermocouple connector are arranged on the side wall of the furnace shell, and the thermocouple connector is matched with the furnace plate assembly in an abutting mode; the furnace plate assembly comprises a furnace plate support and a furnace plate placed on the furnace plate support, a heating rod connected with the electrode wire is arranged on the side wall of the furnace plate, and a sample plate is arranged in the furnace plate; a lower heat insulation pad is arranged between the stove plate bracket and the stove plate; the furnace cover assembly comprises a furnace body sealing cover and a furnace cover seat embedded in the middle of the furnace body sealing cover, the furnace body sealing cover and the furnace shell are fixed in a matched mode through a fastener, an upper glass assembly is arranged on the furnace cover seat corresponding to the sample disc, an upper heat insulation pad is arranged between the furnace cover seat and the furnace disc, and the upper heat insulation pad is fixed to the bottom of the furnace cover seat. The vacuum environment and the high-heat-resistance furnace plate support are adopted for heat insulation, and the temperature control range can be obviously widened.

Description

Technical Field

[0001] The utility model belongs to the technical field of material heating devices, and in particular relates to a miniature visible vacuum furnace. Background Art

[0002] Laser flash method (LFM) is a transient method for measuring the thermal diffusivity of materials. Laser thermal conductivity meters based on the principle of laser flash method are widely used in the characterization of thermal properties of materials such as ceramics and metals. The standard structure of the laser flash method test device is a light source, a temperature-controlled sample chamber, and a detector from bottom to top. In actual use, due to the small distance between the detector and the light source, the small thickness of the sample chamber and the light transmission from top to bottom, the thermal insulation performance of the sample chamber is poor, and the controllable temperature in the chamber is generally difficult to exceed 300°C. Utility Model Content

[0003] In order to make up for the deficiencies of the prior art, the utility model aims to provide a micro light-transmitting vacuum furnace suitable for the laser flash method, which can provide a vacuum environment from room temperature to 800°C, and can effectively improve the temperature measurement range and accuracy that the device can be compatible with. To achieve this purpose, the specific technical solutions of this application are as follows:

[0004] The miniature visible vacuum furnace comprises a furnace body assembly, a furnace cover assembly and a furnace plate assembly, wherein the furnace body assembly comprises a furnace shell, the furnace shell contains a furnace cavity for placing the furnace plate assembly, a lower glass assembly corresponding to the furnace plate assembly is embedded in the bottom wall of the furnace shell, and electrodes and thermocouple joints are arranged on the side walls of the furnace shell, and the thermocouple joints are abutted and matched with the furnace plate assembly;

[0005] The furnace plate assembly comprises a furnace plate support and a furnace plate placed on the furnace plate support, a heating rod connected to an electrode wire is arranged on a side wall of the furnace plate, and a sample plate is arranged inside the furnace plate; a lower heat insulation pad is arranged between the furnace plate support and the furnace plate;

[0006] The furnace cover assembly includes a furnace body cover and a furnace cover seat embedded in the middle of the furnace body cover. The furnace body cover and the furnace shell are fixed by fasteners. An upper glass assembly is arranged on the furnace cover seat corresponding to the sample plate, and an upper insulation pad is arranged between the furnace cover seat and the furnace plate. The upper insulation pad is fixed to the bottom of the furnace cover seat.

[0007] Furthermore, the furnace plate support comprises an upper frame and a lower frame, the upper frame and the lower frame are connected by connecting columns, the lower frame is arranged on the bottom wall of the furnace shell, and the furnace plate is placed on the upper frame.

[0008] Furthermore, the upper frame and the lower frame are both provided with a plurality of weight-reducing holes, and a connecting plate is provided on the upper frame, and connecting holes are provided on the connecting plate, which are fastened and connected with the lower thermal insulation pad by matching fasteners.

[0009] Furthermore, a ceramic layer is provided on the inner wall of the furnace shell; and an air inlet pipe joint and an air outlet pipe joint are also provided on the side wall of the furnace shell for connecting a vacuum pumping device to perform a vacuum pumping operation on the inside of the furnace chamber.

[0010] Furthermore, four sample trays are arranged in a field shape in the furnace tray, and a cross-shaped through groove is arranged in the middle of the sample tray to place samples while avoiding blocking light and infrared detection.

[0011] Furthermore, a sealing gasket is arranged between the furnace body cover and the furnace shell.

[0012] Furthermore, the upper glass assembly includes a plurality of upper glass windows corresponding to the sample trays, and the upper glass windows include infrared glass lenses.

[0013] Furthermore, the lower glass assembly includes a plurality of lower glass windows corresponding to the sample trays, the lower glass windows include a lens holder and a quartz glass lens arranged on the lens holder, and a sealing ring is arranged between the quartz glass lens and the bottom wall of the furnace shell.

[0014] Compared with the prior art, the utility model has the following advantages:

[0015] (1) In order to increase the temperature rise rate and achieve better temperature control characteristics, the present application adopts direct heating by a heating rod integrated with the furnace plate; compared with the traditional direct heating by a heating wire or heat conduction by an external heat source, the heating of the present application is more stable.

[0016] (2) Different from the traditional insulation method of stacking heavy insulation materials, in order to improve the insulation efficiency, the present application adopts a vacuum environment (i.e., by setting an air inlet pipe joint and an air outlet pipe joint, connecting a vacuum pumping device to evacuate the inside of the furnace chamber) and a high thermal resistance bracket (i.e., a double-layer furnace plate bracket, in which the upper frame and the lower frame are connected by connecting columns, with a small contact area and less heat conduction and heat dissipation) for insulation. In combination with an upper insulation pad and a lower insulation pad, a more ideal insulation effect can be achieved, and the temperature control range can be significantly improved. During use, the temperature control upper limit can be increased to 800°C.

[0017] (3) Different from the traditional complex process, the vacuum furnace of the present application has a simple structure, small size, small heat capacity, and excellent manufacturability. It can be assembled only by connecting with simple screws / bolts, without the need for additional complex thermal insulation measures, and has good safety and stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the utility model;

[0019] Figure 2 This is a bottom structure diagram of the utility model;

[0020] Figure 3 For this utility model Figure 2 Sectional view at AA;

[0021] Figure 4 This is a side structural diagram of the utility model;

[0022] Figure 5 For this utility model Figure 4 Sectional view at the middle BB;

[0023] Figure 6 This is a schematic diagram of the structure of the stove plate support of the utility model;

[0024] Figure 7 This is a schematic diagram of the stove structure of the utility model.

[0025] In the figure: 10-furnace body assembly, 11-furnace shell, 12-lower glass assembly, 121-lower glass window, 1211-lens bracket, 1212-quartz glass lens, 20-furnace cover assembly, 21-furnace body cover, 22-furnace cover seat, 23-upper glass assembly, 231-upper glass window, 24-upper insulation pad, 25-furnace seal insulation pad, 30-furnace plate assembly, 31-furnace plate bracket, 311-upper frame, 312-lower frame, 313-connecting column, 314-weight reduction hole, 315-connecting piece, 32-furnace plate, 33-heating rod, 34-sample plate, 35-lower insulation pad, 40-electrode, 50-thermocouple joint, 60-inlet pipe joint, 70-outlet pipe joint, 80-sealing pad, 90-sealing ring, 100-handle. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the present invention is further described below in conjunction with the accompanying drawings.

[0027] like Figure 1-Figure 5 As shown, a miniature visual vacuum furnace comprises a furnace body assembly 10, a furnace cover assembly 20 and a furnace plate assembly 30. The furnace body assembly 10 comprises a furnace shell 11, the inner wall of the furnace shell 11 is provided with a ceramic layer, the furnace shell 11 is a furnace cavity for placing the furnace plate assembly 30, the bottom wall of the furnace shell 11 is embedded with a lower glass assembly 12 corresponding to the furnace plate assembly 30, the side wall of the furnace shell 11 is provided with an electrode 40 and a thermocouple joint 50, and the thermocouple joint 50 is abutted and matched with the furnace plate assembly 20. The side wall of the furnace shell 11 is also provided with an air inlet pipe joint 60 and an air outlet pipe joint 70, which are used to connect a vacuum pumping device to perform a vacuum pumping operation on the inside of the furnace cavity. In the present application, the lower glass assembly 12 includes a plurality of lower glass windows 121 corresponding to the sample tray 34, and the lower glass window 121 includes a lens bracket 1211 and a quartz glass lens 1212 arranged on the lens bracket 1211, and a sealing ring 90 is arranged between the quartz glass lens 1212 and the bottom wall of the furnace shell 11 to ensure the sealing between the furnace shell 11 and the quartz glass lens 1212.

[0028] The furnace plate assembly 30 includes a furnace plate support 31 and a furnace plate 32 placed on the furnace plate support 31. A heating rod 33 connected to the electrode 40 wire is arranged on the side wall of the furnace plate 32. A sample plate 34 is arranged inside the furnace plate 32. A lower heat insulation pad 35 is arranged between the furnace plate support 31 and the furnace plate 32. Figure 6 As shown, the furnace plate support 31 includes an upper frame 311 and a lower frame 312, the upper frame 311 and the lower frame 312 are connected by a connecting column 313, the lower frame 312 is arranged on the bottom wall of the furnace shell 11, and the furnace plate 32 is placed on the upper frame 311. Among them, the upper frame 311 and the lower frame 312 are both provided with a plurality of weight-reducing holes 314 to reduce weight, and the upper frame 311 is provided with a connecting piece 315, and the connecting piece 315 is provided with a connecting hole, which cooperates with a fastener to be fastened and connected with the lower heat insulation pad 35. The fastener is preferably a screw / bolt assembly.

[0029] The furnace cover assembly 20 includes a furnace body cover 21 and a furnace cover seat 22 embedded in the middle of the furnace body cover 21. The furnace body cover 21 is fixed to the furnace shell 11 by fasteners. An upper glass assembly 23 is arranged on the furnace cover seat 22 corresponding to the sample tray 34, and an upper heat insulation pad 24 is arranged between the furnace cover seat 22 and the furnace tray 32. The upper heat insulation pad 24 is fixed to the bottom of the furnace cover seat 22. In order to further ensure the sealing of the furnace cavity, a furnace sealing heat insulation pad 25 is arranged between the furnace body cover 21 and the furnace cover seat 22; and a sealing pad 80 is arranged between the furnace body cover 21 and the furnace shell 11. In the present application, the upper glass assembly 23 includes a plurality of upper glass windows 231 corresponding to the sample tray 34, and the upper glass windows 231 include infrared glass lenses. In order to facilitate the taking of the furnace cover assembly 20, a handle 100 is arranged on the upper glass assembly 23.

[0030] like Figure 7 As shown, in this embodiment, four sample trays 34 are arranged in a field shape, and a cross-shaped through groove is provided in the middle of the sample tray 34 to place the sample without blocking light and infrared detection. The upper glass window 231 and the lower glass window 121 are four corresponding to the sample tray 34, so as to observe the state of the sample in the furnace in real time. The upper insulation pad 24 and the lower insulation pad 35 are both provided with through holes corresponding to the sample tray 34 to avoid blocking the line of sight and light.

[0031] It can be understood that the stove tray bracket 31 of the present application is designed as a double-layer bracket, the upper frame 311 and the lower frame 312 are connected by the connecting column 313, and the two layers of the frame are connected only by the connecting column 313 to reduce the contact area, reduce heat conduction, and achieve the purpose of less heat dissipation; the upper insulation pad 24 is provided to reduce the heat transfer between the stove tray 32 and the furnace cover assembly 30; the lower insulation pad 35 is provided to reduce the heat transfer between the stove tray 32 and the stove tray bracket 31 and the furnace shell 11. Even if the vacuum furnace of the present application is small in size, it can achieve a relatively ideal insulation effect and significantly improve the temperature control range. During use, it can be increased to an upper temperature control limit of 800°C.

[0032] In the present application, a vacuuming device connected to the air inlet pipe joint 60 and the air outlet pipe joint 70 is used to evacuate the furnace chamber to reduce the heat transfer medium, reduce heat transfer, and ensure the heating temperature of the sample; and a protective gas is introduced through an inflation device connected to the air inlet pipe joint 80 and the air outlet pipe joint 90 to quickly and evenly cool down the temperature.

[0033] When the present application is in use, the furnace cover assembly 20 is opened to place the sample on the sample tray 34, the furnace cover assembly 20 is closed, and the vacuum furnace is moved to the working position; a start signal is given (i.e., the solenoid valve is opened to open the pipeline, an operation step known to those skilled in the art), and a vacuum is drawn through a vacuum pumping device (not shown in the figure) connected to the air inlet pipe joint 60 and the air outlet pipe joint 70; the solenoid valve is closed to close the pipeline; the temperature is raised to the set temperature and then kept warm until the temperature is stable; after the experiment is completed, a protective gas is introduced through an air inlet pipe joint 60 and an air outlet pipe joint 70 to connect an inflation device (not shown in the figure) to quickly cool down the temperature, and after the temperature drops to a safe range, the furnace cover assembly 20 is opened to replace the sample.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the utility model.

Claims

1. A miniature visual vacuum furnace, comprising a furnace body assembly (10), a furnace cover assembly (20) and a furnace plate assembly (30), characterized in that: The furnace body assembly (10) comprises a furnace shell (11), the furnace shell (11) contains a furnace cavity for placing a furnace plate assembly (30), a lower glass assembly (12) corresponding to the furnace plate assembly (30) is embedded in the bottom wall of the furnace shell (11), and electrodes (40) and a thermocouple joint (50) are arranged on the side wall of the furnace shell (11), and the thermocouple joint (50) is in abutment with the furnace plate assembly (30); The furnace plate assembly (30) comprises a furnace plate support (31) and a furnace plate (32) placed on the furnace plate support (31); a heating rod (33) connected to an electrode (40) wire is arranged on a side wall of the furnace plate (32); a sample plate (34) is arranged inside the furnace plate (32); and a lower heat insulation pad (35) is arranged between the furnace plate support (31) and the furnace plate (32); The furnace cover assembly (20) comprises a furnace body cover (21) and a furnace cover seat (22) embedded in the middle of the furnace body cover (21); the furnace body cover (21) and the furnace shell (11) are fixed together by fasteners; an upper glass assembly (23) is arranged on the furnace cover seat (22) corresponding to the sample plate (34); and an upper heat insulation pad (24) is arranged between the furnace cover seat (22) and the furnace plate (32); the upper heat insulation pad (24) is fixed to the bottom of the furnace cover seat (22).

2. A micro visible vacuum furnace according to claim 1, characterized in that: The furnace pan support (31) comprises an upper frame (311) and a lower frame (312); the upper frame (311) and the lower frame (312) are connected via a connecting column (313); the lower frame (312) is arranged on the bottom wall of the furnace shell (11); and the furnace pan (32) is placed on the upper frame (311).

3. A micro visible vacuum furnace according to claim 2, characterized in that: The upper frame (311) and the lower frame (312) are both provided with a plurality of weight-reducing holes (314), and a connecting sheet (315) is provided on the upper frame (311). The connecting sheet (315) is provided with connecting holes, and is fastened and connected to the lower thermal insulation pad (35) by means of fasteners.

4. The micro visible vacuum furnace according to claim 1, characterized in that: The inner wall of the furnace shell (11) is provided with a ceramic layer; and the side wall of the furnace shell (11) is also provided with an air inlet pipe joint (60) and an air outlet pipe joint (70) for connecting a vacuum extraction device to perform a vacuum extraction operation on the interior of the furnace chamber.

5. The micro visible vacuum furnace according to claim 1, characterized in that: Four sample trays (34) are arranged in the furnace tray (32), the four sample trays (34) are arranged in a field shape, and a cross-shaped through slot is arranged in the middle of the sample tray (34), so as to place samples while avoiding blocking light and infrared detection.

6. The micro visible vacuum furnace according to claim 1, characterized in that: A sealing gasket (80) is provided between the furnace body cover (21) and the furnace shell (11).

7. A micro visible vacuum furnace according to any one of claims 1 to 6, characterized in that: The upper glass assembly (23) comprises a plurality of upper glass windows (231) corresponding to the sample tray (34), and the upper glass windows (231) comprise infrared glass lenses.

8. A micro visible vacuum furnace according to any one of claims 1 to 6, characterized in that: The lower glass assembly (12) comprises a plurality of lower glass windows (121) corresponding to the sample tray (34); the lower glass window (121) comprises a lens support (1211) and a quartz glass lens (1212) arranged on the lens support (1211); and a sealing ring (90) is arranged between the quartz glass lens (1212) and the bottom wall of the furnace shell (11).

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