High-temperature-resistant thermocouple structure

Abstract

The utility model discloses a high-temperature-resistant thermocouple structure, which comprises a head shell, a first slender rod, a second slender rod and a third slender rod, the first slender rod and the second slender rod are arranged in an inner cavity of the head shell, and the third slender rod extends out of the head shell; the head end of the first slender rod is welded with the top end of the head shell to form a top arc-shaped welding structure; a flame heating position is formed at the joint of the head of the first slender rod and the top of the head shell; the first slender rod, the second slender rod and the third slender rod are welded in sequence; side arc-shaped welding structures are formed between the first slender rod and the second slender rod and between the second slender rod and the third slender rod; the first slender rod is a nickel-silicon slender rod or a nickel-chromium slender rod. The slender rods in the high-temperature-resistant thermocouple structure are designed in a three-section structure, the slender rods located at the flame heating position are nickel-silicon slender rods or nickel-chromium slender rods, the thermocouple structure can be used for a long time under the high-temperature condition, meanwhile, the reliability of a welding structure between the slender rods is high, and the service life of the whole thermocouple structure is further prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of thermocouples, in particular to a high-temperature resistant thermocouple structure. Background Art

[0002] In actual use, the stove flame directly heats the tip of the thermocouple head, creating a significant temperature difference between the head's outer shell and the interior of the stem. Existing thermocouple head designs typically utilize a two-section welded stem: the upper stem is made of constantan, and the lower stem is made of nickel-chromium alloy. Constantan stems are known for their sensitive response to temperature differences, high electromotive force, and excellent stability. Nickel-chromium stems offer excellent thermal and electrical conductivity and oxidation resistance. At high temperatures, they form a dense oxide film, preventing further oxygen contact with the alloy and preventing oxidation.

[0003] As market demand increases, the power of household and commercial gas stoves increases, and flame temperatures rise. The existing Constantan rods at the top of the thermocouples struggle to withstand temperatures around 900°C. The operating temperature of the Constantan rods is limited to 650°C for short-term use and 550°C for long-term use. When used at 900°C, the lifespan of the thermocouples is significantly shortened. Furthermore, long-term high-temperature use can cause the Constantan rods to gradually corrode and fracture at the point where the flames are heating, leading to failure of the thermocouples.

[0004] In addition, in the existing thermocouple structure, the thin rod welding structure still has problems such as poor reliability and unsatisfactory welding quality. Utility Model Content

[0005] To address the aforementioned technical issues, the present invention provides a high-temperature-resistant thermocouple structure. The thin rods in this thermocouple adopt a three-section design, and the thin rods in the flame-heating position are nickel-silicon thin rods or nickel-chromium thin rods. This structure can be used for long periods of time under high-temperature conditions exceeding 1000°C. The welded structure between the thin rods is highly reliable, further extending the service life of the entire thermocouple structure.

[0006] In order to achieve the above technical objectives and the above technical effects, the present invention is implemented through the following technical solutions:

[0007] A high temperature resistant thermocouple structure, comprising:

[0008] head shell;

[0009] First thin rod;

[0010] the second thin rod;

[0011] and a third thin rod;

[0012] The first thin rod and the second thin rod are arranged in the inner cavity of the head shell, and the third thin rod extends out of the head shell; the head end of the first thin rod is welded to the top end of the head shell by fusion welding to form a top arc welding structure; the flame heating position is formed at the junction of the head of the first thin rod and the top of the head shell; the first thin rod, the second thin rod, and the third thin rod are welded in sequence by fusion welding; side arc welding structures are formed between the first thin rod and the second thin rod, and between the second thin rod and the third thin rod;

[0013] The first thin rod is a nickel silicon thin rod or a nickel chromium thin rod.

[0014] Furthermore, the second thin rod is a constantan thin rod; and the third thin rod is a nickel-chromium thin rod.

[0015] Furthermore, the head shell is a nickel-chromium shell.

[0016] Furthermore, the flame heating position ranges from 3 to 5 mm.

[0017] The beneficial effects of the utility model are:

[0018] The thin rod in the thermocouple structure of the present invention adopts a three-section structural design, and the thin rod at the flame heating position adopts a nickel-silicon thin rod or a nickel-chromium thin rod. The use range of nickel-silicon and nickel-chromium materials is 1300°C in the short term and 1100°C in the long term, so that the thermocouple structure can be used for a long time under high temperature conditions greater than 1000°C, solving the problem in the prior art that the constantan thin rod slowly corrodes and breaks at the flame heating position, resulting in failure of the thermocouple product performance.

[0019] Furthermore, the head end of the first thin rod and the top end of the head shell are welded by melting welding to form a top arc welding structure; side arc welding structures are formed between the first thin rod and the second thin rod and between the second thin rod and the third thin rod; the design of the top arc welding structure and the side arc welding structure makes the welding structure more enveloping, improves the connection reliability of the welding structure, and further improves the service life of the entire thermocouple structure; and the use of melting welding based on the thin rod material can also reduce the cost of welding materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a structural diagram of the high-temperature resistant thermocouple structure of the utility model.

[0021] 1: Head shell; 2: First thin rod; 3: Second thin rod; 4: Third thin rod; 5: Flame heating position; 6: Top arc welding structure; 7: Side arc welding structure. DETAILED DESCRIPTION

[0022] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more precise definition of the protection scope of the present invention.

[0023] like Figure 1 A preferred embodiment of a high-temperature resistant thermocouple structure is shown, which includes a head shell 1, a first thin rod 2, a second thin rod 3, and a third thin rod 4; the first thin rod 2 and the second thin rod 3 are arranged in the inner cavity of the head shell 1, and the third thin rod 4 extends outward from the head shell 1; the head end of the first thin rod 2 is welded to the top of the head shell 1 by fusion welding to form a top arc welding structure 6; the flame heating position 5 is formed at the junction of the head of the first thin rod 2 and the top of the head shell 1; the first thin rod 2, the second thin rod 3, and the third thin rod 4 are welded in sequence by fusion welding; side arc welding structures 7 are formed between the first thin rod 2 and the second thin rod 3 and between the second thin rod 3 and the third thin rod 4;

[0024] The first thin rod 2 is a nickel silicon thin rod or a nickel chromium thin rod.

[0025] Wherein, the second thin rod 3 is a constantan thin rod; the third thin rod 4 is a nickel-chromium thin rod.

[0026] Wherein, the head shell 1 is a nickel-chromium shell.

[0027] When the thermocouple structure is in use, the flame heating position ranges from 3 to 5 mm.

[0028] The thin rod in the thermocouple structure of the present invention adopts a three-section structural design, and the thin rod at the flame heating position adopts a nickel-silicon thin rod or a nickel-chromium thin rod. The use range of nickel-silicon and nickel-chromium materials is 1300°C for a short period and 1100°C for a long period. They have excellent oxidation resistance and corrosion resistance at temperatures greater than 1000°C, so that the thermocouple structure can be used for a long time under high temperature conditions greater than 1000°C, solving the problem in the prior art that the constantan thin rod slowly corrodes and breaks at the flame heating position, resulting in failure of the thermocouple product performance.

[0029] During welding, the head end of the first thin rod 2 and the top end of the head shell 1 are welded by melting welding to form a top arc welding structure 6; a side arc welding structure 7 is formed between the first thin rod 2 and the second thin rod 3 and between the second thin rod 3 and the third thin rod 4; the design of the top arc welding structure 6 and the side arc welding structure 7 makes the welding structure more wrapping, improves the connection reliability of the welding structure, and further improves the service life of the entire thermocouple structure; and the use of melting welding based on the thin rod material can also reduce the cost of welding materials.

[0030] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be encompassed within the present invention. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0031] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A high temperature resistant thermocouple structure, characterized in that: include: head shell; First thin rod; the second thin rod; and a third thin rod; The first thin rod and the second thin rod are arranged in the inner cavity of the head shell, and the third thin rod extends out of the head shell; the head end of the first thin rod is welded to the top end of the head shell by fusion welding to form a top arc welding structure; the flame heating position is formed at the junction of the head of the first thin rod and the top of the head shell; the first thin rod, the second thin rod, and the third thin rod are welded in sequence by fusion welding; side arc welding structures are formed between the first thin rod and the second thin rod, and between the second thin rod and the third thin rod; The first thin rod is a nickel silicon thin rod or a nickel chromium thin rod.

2. A high temperature resistant thermocouple structure according to claim 1, characterized in that: The second thin rod is a constantan thin rod; the third thin rod is a nickel-chromium thin rod.

3. A high temperature resistant thermocouple structure according to claim 1, characterized in that: The head shell is a nickel-chromium shell.

4. A high temperature resistant thermocouple structure according to claim 1, characterized in that: The flame heating position ranges from 3 to 5 mm.

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