A noble metal thermocouple energized annealing cabinet and method for realizing automatic cleaning

Abstract

The present invention relates to a noble metal thermocouple energized annealing cabinet and method for realizing automatic cleaning, and belongs to the field of noble metal thermocouple cleaning. The present invention comprises an electrode for storing and melting borax, and the electrode comprises a corundum shell, a heating wire and a pure platinum elastic buckle, the heating wire is fixed on the corundum shell, a small hole is provided at the lower part of the corundum shell, the pure platinum elastic buckle is located directly below the small hole, the upper end of the heating wire is connected to a DC power supply, and the lower end of the heating wire is connected to the pure platinum elastic buckle. The present invention has reasonable structural design, is safe and reliable, does not require manual operation during the whole process of borax washing, is easy to clean, avoids contamination of the noble metal thermocouple, and meets the use requirements.

Description

Technical Field

[0001] The invention relates to an annealing cabinet and a method thereof, in particular to an automatic cleaning noble metal thermocouple energized annealing cabinet and a method thereof, and belongs to the field of noble metal thermocouple cleaning. Background Art

[0002] Cleaning of precious metal thermocouples (S type, R type, B type) requires acid washing and borax washing. Borax washing is to hang the precious metal thermocouple in an electric annealing furnace, pass a 10.5A current, heat it to about 1100℃, and use a small piece of chemically pure borax to contact the upper end of the electrode. After the borax melts, it flows down in a forward direction to clean the dirt on the electrode. After washing (2-3) times, turn off the power.

[0003] At present, the cleaning of precious metal thermocouples still relies on manual operation. During the operation, people hold insulated tweezers and apply small pieces of chemically pure borax to the energized, hot thermocouple wire, which is a relatively dangerous operation. Moreover, at this time, the end of the thermocouple wire is bent and hung on the electrode. The bent part is not energized and therefore cannot be cleaned with borax.

[0004] A Chinese patent with a publication date of August 28, 2012 and a publication number of CN202372262U discloses a utility model patent named "thermocouple cleaning protection device". The thermocouple cleaning protection device includes a protection box and a sealing ring. The protection box is provided with a hole, and the sealing ring is stuck in the hole to form a sealed connection with the hole. Although the patent can effectively prevent the acid cleaning liquid vapor from corroding the thermocouple rear end signal line and the signal line plug; it cannot completely achieve borax cleaning, so it still has the above-mentioned defects.

[0005] Therefore, it is particularly necessary to provide a safe and reliable noble metal thermocouple powered annealing cabinet which does not require manual operation during the entire borax washing process and can achieve automatic cleaning to avoid contamination of the noble metal thermocouple. Summary of the invention

[0006] The object of the present invention is to overcome the above-mentioned shortcomings in the prior art and to provide a noble metal thermocouple energized annealing cabinet and method thereof which has a reasonable structural design, is safe and reliable, does not require manual operation during the entire borax washing process, is easy to clean, and avoids contamination of the noble metal thermocouple and realizes automatic cleaning.

[0007] The technical solution adopted by the present invention to solve the above problem is: the noble metal thermocouple powered annealing cabinet realizing automatic cleaning comprises an electrode for storing and melting borax, and is characterized in that: the electrode comprises a corundum shell, a heating wire and a pure platinum elastic buckle, the heating wire is fixed on the corundum shell, a small hole is provided at the lower part of the corundum shell, the pure platinum elastic buckle is located directly below the small hole, the upper end of the heating wire is connected to a DC power supply, and the lower end of the heating wire is connected to the pure platinum elastic buckle.

[0008] Preferably, the corundum shell of the present invention comprises a corundum shell inner layer and a corundum shell outer layer, and both the inner side of the corundum shell outer layer and the outer side of the corundum shell inner layer have vortex-shaped grooves that match the shape of the heating wire.

[0009] Preferably, the corundum shell of the present invention is a conical corundum shell.

[0010] Preferably, the working temperature of the heating wire of the present invention is above 900°C, and the lower end is welded to the pure platinum elastic buckle; the working temperature must reach above 900°C to melt the borax, and the welding is firm and will not melt due to high temperature.

[0011] Preferably, the heating wire of the present invention is a spiral heating wire.

[0012] Preferably, the heating wire of the present invention is made of pure platinum wire.

[0013] The present invention also provides a method for using a noble metal thermocouple powered annealing cabinet that can achieve automatic cleaning, which is characterized by the following steps: when in use, before power is turned on, the two reference ends of the noble metal thermocouple are respectively inserted into the pure platinum elastic buckles of the positive and negative electrodes to make them in a suspended state, and a proper amount of borax is added into the conical corundum shell; the annealing cabinet door is closed, power is turned on, and the current is slowly increased until the annealing temperature specified for the noble metal thermocouple is reached, while the heating wire in the electrode is also in the powered state, heating and melting the borax in the corundum shell, and the borax solution drips from the small hole at the bottom of the corundum shell, drips onto the pure platinum elastic buckle at the lower end of the heating wire, and slowly flows down along the noble metal thermocouple wire to dissolve and clean the metal oxide on the surface of the wire; after annealing for a specified time, the current is automatically reduced until the power is turned off.

[0014] Compared with the prior art, the present invention has the following advantages and effects: 1) The overall structural design is reasonable, safe and reliable, and easy to clean. Borax washing does not require manual operation throughout the process, avoiding the risk of electric shock and burns; 2) The reference end of the precious metal thermocouple (also the wiring part) is connected to the electrode without bending, and the entire length can be cleaned by borax droplets, avoiding the influence of the measurement result on the dirty reference end of the thermocouple; 3) The part where the electrode contacts the precious metal thermocouple is made of pure platinum to avoid contamination of the precious metal thermocouple. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic structural diagram of an embodiment of the present invention.

[0016] Figure 2 Schematic diagram of the structure of the electrode according to the embodiment of the present invention.

[0017] Figure 3 yes Figure 2 Schematic diagram of the local enlarged structure at point A in the middle.

[0018] Figure 4 It is a schematic diagram of the structure of the inner layer of the corundum shell according to an embodiment of the present invention.

[0019] Figure 5 It is a schematic diagram of the structure of the heating wire according to an embodiment of the present invention.

[0020] Figure 6 It is a schematic diagram of the structure of the outer layer of the corundum shell according to an embodiment of the present invention.

[0021] In the figure: electrode 1, corundum shell 2, corundum shell inner layer 3, heating wire 4; corundum shell outer layer 5, pure platinum elastic buckle 6, small hole 7. DETAILED DESCRIPTION

[0022] The present invention will be further described in detail below with reference to the accompanying drawings and by way of examples. The following examples are intended to explain the present invention but the present invention is not limited to the following examples.

[0023] Example

[0024] See also Figures 1 to 6 The precious metal thermocouple cleaning annealing cabinet for automatic cleaning of this embodiment includes an electrode 1 that can store and melt borax, and the electrode 1 includes a conical corundum shell 2, a vortex-shaped heating wire 4 and a pure platinum elastic buckle 6; the heating wire 4 is wrapped with a conical corundum shell 2 to play an insulating role.

[0025] The corundum shell 2 of this embodiment includes a corundum shell inner layer 3 and a corundum shell outer layer 5. The inner side of the corundum shell outer layer 5 and the outer side of the corundum shell inner layer 3 are both provided with vortex-shaped grooves, which match the shape of the heating wire 4, have the function of fixing the heating wire 4, and can prevent short circuit from occurring inside the heating wire 4.

[0026] In this embodiment, a small hole 7 is provided at the bottom of the corundum shell 2 for dripping the melted borax.

[0027] In this embodiment, the upper end of the heating wire 4 is connected to a DC power supply, and the lower end of the heating wire 4 is connected to a pure platinum elastic buckle 6; the pure platinum elastic buckle 6 is located directly below the small hole 7 of the corundum shell 2, and the wire of the precious metal thermocouple can be inserted and clamped.

[0028] The heating wire 4 of this embodiment is made of pure platinum wire, and can also be replaced by other materials, but its working temperature must reach above 900°C to melt the borax, and the lower end is firmly welded to the pure platinum elastic buckle 6, and will not be melted due to high temperature;

[0029] When in use, before powering on, insert the two reference ends of the precious metal thermocouple into the pure platinum elastic buckles 6 of the positive and negative electrodes 1 respectively, so that they are in a suspended state, and add an appropriate amount of borax into the conical corundum shell 2. Close the annealing cabinet door, start the program through the control panel 2 to power on, and slowly increase the current until the annealing temperature specified for this precious metal thermocouple. Because the heating wire 4 in the electrode 1 is also in the power-on state, the borax in the corundum shell 2 is heated and melted, and the borax solution drips from the small hole 7 at the bottom of the corundum shell 2, drips onto the pure platinum elastic buckle 6 at the lower end of the heating wire 4, and slowly flows down along the precious metal thermocouple wire, dissolving and cleaning the metal oxide on the surface of the wire; after the specified annealing time, the current is automatically reduced until the power is turned off.

[0030] In this embodiment, by changing the structure of electrode 1, the precious metal thermocouple is connected to electrode 1 without bending, and current is carried along the entire length; a structure capable of storing borax powder is added, and when power is turned on, the borax melts due to the heat and slowly flows out of electrode 1, flows down along the precious metal thermocouple wire, and cleans the metal compounds on the surface of the thermocouple, thereby realizing the automation of the entire borax washing process and avoiding operational risks.

[0031] Through the above description, those skilled in the art can already implement it.

[0032] In addition, it should be noted that the shapes and names of the parts and components of the specific embodiments described in this specification may be different, and the above content described in this specification is only an example of the structure of the present invention. All equivalent changes or simple changes made based on the structure, features and principles described in the patent concept of the present invention are included in the protection scope of the patent of the present invention. Technicians in the technical field of the present invention can make various modifications or supplements to the specific embodiments described or replace them in a similar manner, as long as they do not deviate from the structure of the present invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A noble metal thermocouple annealing cabinet capable of automatically cleaning, comprising an electrode (1) for storing and melting borax, characterized in that: The electrode (1) comprises a corundum shell (2), a heating wire (4) and a pure platinum elastic buckle (6); the heating wire (4) is fixed on the corundum shell (2); a small hole (7) is provided at the bottom of the corundum shell (2); the pure platinum elastic buckle (6) is located directly below the small hole (7); the upper end of the heating wire (4) is connected to a DC power supply; the lower end of the heating wire (4) is connected to the pure platinum elastic buckle (6); the corundum shell (2) comprises a corundum shell inner layer (3) and a corundum shell outer layer (5); the inner side of the corundum shell outer layer (5) and the outer side of the corundum shell inner layer (3) are both provided with vortex-shaped grooves, which match the shape of the heating wire (4); the corundum shell (2) is a conical corundum shell (2); the working temperature of the heating wire (4) is above 900° C., and the lower end is welded to the pure platinum elastic buckle (6).

2. The noble metal thermocouple energized annealing cabinet capable of realizing automatic cleaning according to claim 1, characterized in that: The heating wire (4) is a spiral heating wire.

3. The noble metal thermocouple energized annealing cabinet with automatic cleaning according to claim 1, characterized in that: The heating wire (4) is made of pure platinum wire.

4. A method for using a noble metal thermocouple energized annealing cabinet that realizes automatic cleaning, using the noble metal thermocouple energized annealing cabinet that realizes automatic cleaning according to any one of claims 1 to 3, characterized in that: The steps are as follows: when in use, before power is turned on, the two reference ends of the precious metal thermocouple are respectively inserted into the pure platinum elastic buckles (6) of the positive and negative electrodes (1) to make them in a suspended state, and a proper amount of borax is added into the conical corundum shell (2); the annealing cabinet door is closed, power is turned on, and the current is slowly increased until the annealing temperature specified for the precious metal thermocouple is reached, and the heating wire (4) in the electrode (1) is also in the power-on state, heating and melting the borax in the corundum shell (2), and the borax solution drips from the small hole (7) at the bottom of the corundum shell (2), drips onto the pure platinum elastic buckle (6) at the lower end of the heating wire (4), and slowly flows down along the precious metal thermocouple wire, dissolving and cleaning the metal oxide on the surface of the wire; after the specified annealing time, the current is automatically reduced until the power is turned off.

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