Novel transformer low-voltage coil inner supporting cylinder structure

Abstract

The invention discloses a novel transformer low-voltage coil inner supporting cylinder structure which comprises an insulating hard paper cylinder arranged on the periphery of a coil adjustable winding mold in a sleeving mode, a plurality of coil supporting strips and an insulating spacer assembly, the coil supporting strips are fixed to the periphery of the insulating hard paper cylinder in an adhering mode, and the insulating spacer assembly is arranged on the periphery of the insulating hard paper cylinder. The coil stays are uniformly distributed on the periphery of the insulating hard paper tube at intervals, and the insulating spacer assemblies are arranged on the periphery of the coil stays in a sleeving manner; the invention relates to the technical field of transformer coils. According to the novel inner supporting cylinder structure for the low-voltage coil of the transformer, the insulating hard paper cylinder is used for replacing a traditional glass fiber cylinder, the novel inner supporting cylinder structure has more excellent mechanical strength and electrical performance, meanwhile, the production cost can be further reduced, the cost reducing and efficiency increasing effects are achieved, the mechanical strength of the insulating hard paper cylinder is improved through the adhesion strips, and the service life is prolonged. And convenient positioning conditions can be provided for installation of the insulating spacer, winding forming of a coil wire cake is facilitated, and the insulating isolation effect is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of transformer coils, and in particular to a novel inner support cylinder structure for a transformer low-voltage coil. Background Art

[0002] In order to ensure that the transformer low-voltage coil has high mechanical strength in the event of a sudden short circuit, the low-voltage inner support tube is often designed as a glass fiber tube. This tube is a high-strength cast glass fiber tube with a wall thickness of 5mm, and the production cost of purchased parts is high.

[0003] With increasingly fierce competition in the transformer market, reducing design and manufacturing costs while ensuring high performance is crucial. With the development and application of new materials, processes, and electromagnetic software, as well as technological advancements, new coil support tube structures are being sought to reduce manufacturing costs. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the present invention provides a novel inner support cylinder structure for a low-voltage coil of a transformer, which solves the problems raised in the above-mentioned background technology.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: a novel transformer low-voltage coil inner support cylinder structure, comprising an insulating cardboard cylinder sleeved on the outer periphery of an adjustable coil winding mold, a coil support bar, and an insulating gasket assembly; The coil stays are adhered and fixed to the outer circumference of the insulating cardboard tube. There are a plurality of coil stays, which are evenly distributed on the outer circumference of the insulating cardboard tube. The insulating gasket assembly is sleeved on the outer circumference of the coil stays.

[0006] The present invention is further configured as follows: the method for preparing the insulating cardboard tube comprises: A1. Use a groove milling machine to process grooves on both ends of high-density insulation paper to obtain blanks; A2, 0.4-0.5kg / m 2 After spraying distilled water on the surface of the blank, wrap it with plastic cloth and keep it moist for 16-24 hours; A3. Place the moistened blank into a rounding machine and roll it into a round shape using the upper roller. Repeat the rounding process 10-15 times using the groove as the overlapped part. Place the blank in an aluminum mold with an appropriate diameter and vacuum dry it to obtain a dry blank. A4. Apply epoxy resin glue to the overlapping parts of the dry blanks, fix the overlapping positions with G-type clamps, place them in the bonding machine mold, and bond them at 4-6MPa for 50-60 minutes to obtain the semi-finished product; A5. Immerse the semi-finished product in 25# transformer oil for 30-40 minutes at an oil temperature of 60-80°C. Take it out and drain the oil. Wrap it with plastic sheeting and sealing tape and store it upright in a heat-insulating drying room with a temperature of 40-50°C and a humidity of ≤30%.

[0007] The present invention is further configured as follows: the vacuum drying method in A3 includes: A31, preheating stage: temperature 98-102 ℃, vacuum degree 55000-65000Pa, keep warm for 20min; A32, step-by-step transition stage: gradually evacuate to 10000Pa, and keep warm for 20 minutes after each evacuation; A33. High vacuum stage: temperature 125°C, vacuum degree below 200Pa, lasting 100-140 minutes, until the moisture content is less than 1%.

[0008] The present invention is further configured as follows: the insulating gasket assembly includes two adhesive strips, and a plurality of insulating gaskets are adhered and fixed between the two adhesive strips.

[0009] The present invention is further configured as follows: the coil stay is arranged in a T-shape, a slot is provided on one side of the insulating gasket, and the slot is used in conjunction with the coil stay.

[0010] The present invention is further configured such that: the adhesive strip is adhered and fixed to the outer periphery of the insulating cardboard tube.

[0011] The present invention is further configured such that: a plurality of coil bobbins are wound around the peripheries of a plurality of the coil stays.

[0012] The present invention is further configured such that: the insulating gasket is arranged between two adjacent coil bobbins.

[0013] The present invention provides a novel transformer low-voltage coil inner support cylinder structure, which has the following beneficial effects: The present invention utilizes an insulating cardboard tube to replace the traditional glass fiber tube, which has better mechanical strength and electrical performance. At the same time, it can further reduce production costs and achieve the effect of reducing costs and increasing efficiency. The adhesive strip is used to improve the mechanical strength of the insulating cardboard tube, and it can also provide convenient positioning conditions for the installation of the insulating gasket, facilitate the winding and forming of the coil, and ensure the insulation isolation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 Schematic diagram of the external structure of the present invention in the winding state; Figure 2 This is a schematic diagram of the structure of the present invention before winding; Figure 3This is a schematic diagram of the connection structure of the insulating cardboard tube, coil support bar and insulating gasket assembly of the present invention; Figure 4 It is a structural schematic diagram of the coil support bar and insulating spacer assembly of the present invention.

[0015] In the picture: 1. Coil adjustable winding mold; 2. Insulated cardboard tube; 3. Coil stays; 4. Insulating gasket assembly; 401. Adhesive strip; 402. Insulating gasket; 403. Card slot; 5. Coil wire cake. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention.

[0017] See also Figure 1-4 , the embodiment of the present invention provides the following technical solutions: Example 1 A new type of internal support tube structure for a low-voltage coil of a transformer includes an insulating cardboard tube 2, a coil support bar 3, and an insulating gasket assembly 4, which is sleeved on the outer periphery of an adjustable coil winding mold 1. The coil coil 5 is wound using the adjustable coil winding mold 1, and several coil coils 5 are wound together on the outer peripheries of several coil support bars 3. The coil support bars 3 are adhered and fixed to the outer periphery of the insulating cardboard tube 2. The coil support bars 3 are arranged in a T-shape. There are several coil support bars 3, and they are evenly distributed on the outer periphery of the insulating cardboard tube 2. The insulating gasket assembly 4 is sleeved on the outer periphery of the coil support bars 3.

[0018] As a preferred solution, in order to improve the mechanical strength of the insulating cardboard tube 2 and ensure the insulation effect of the coil bobbin 5, the insulating gasket assembly 4 includes two adhesive strips 401, which are adhered and fixed to the outer periphery of the insulating cardboard tube 2. Several insulating gaskets 402 are adhered and fixed between the two adhesive strips 401. A card slot 403 is provided on one side of the insulating gasket 402. The card slot 403 is used in conjunction with the coil support bar 3, and the insulating gasket 402 is arranged between two adjacent coil bobbins 5.

[0019] The preparation method of the insulating cardboard tube 2 includes: A1. Use a groove milling machine to process grooves on both ends of high-density insulation paper to obtain blanks; A2, 0.4kg / m 2 After spraying distilled water on the surface of the blank, wrap it with plastic sheeting and keep it moist for 16 hours; A3. Place the wetted blank into a rounding machine and roll it into a round shape using the upper pressing roller. Repeat the rounding process 10 times using the groove as the overlapped part. Place the blank in an aluminum mold with an appropriate diameter and vacuum dry it to obtain a dry blank. The vacuum drying method includes: A31, preheating stage: temperature 98 ℃, vacuum degree 65000Pa, keep warm for 20 minutes; A32, step-by-step transition stage: gradually evacuate to 10000Pa, and keep warm for 20 minutes after each evacuation; A33, high vacuum stage: temperature 125 ° C, vacuum degree 200 Pa, lasting 100 minutes, until the moisture content is less than 1%; A4. Apply epoxy resin glue to the overlapping parts of the dry blanks, fix the overlapping positions with G-type clamps, place them in the bonding machine mold, and bond them at 4MPa for 60 minutes to obtain the semi-finished product; A5. Immerse the semi-finished product in 25# transformer oil for 30 minutes at an oil temperature of 80°C. Take it out and drain the oil. Wrap it with plastic sheeting and sealing tape. Store it upright in an insulated drying room at a temperature of 40°C and a humidity of 30%.

[0020] Example 2 The difference between this embodiment and the first embodiment is that the method for preparing the insulating cardboard tube 2 includes: A1. Use a groove milling machine to process grooves on both ends of high-density insulation paper to obtain blanks; A2, 0.5kg / m 2 After spraying distilled water on the surface of the blank, wrap it with plastic sheeting and keep it moist for 24 hours; A3. Place the wetted blank into a rounding machine and roll it into a round shape using the upper pressing roller. Repeat the rounding 15 times using the groove as the overlapped part. Place the blank in an aluminum mold with an appropriate diameter and vacuum dry it to obtain a dry blank. The vacuum drying method includes: A31, preheating stage: temperature 102 ℃, vacuum degree 55000Pa, keep warm for 20min; A32, step-by-step transition stage: gradually evacuate to 10000Pa, and keep warm for 20 minutes after each evacuation; A33, high vacuum stage: temperature 125 ° C, vacuum degree 195 Pa, lasting 120 minutes, until the moisture content is less than 1%; A4. Apply epoxy resin glue to the overlapping parts of the dry blanks, fix the overlapping positions with G-type clamps, place them in the bonding machine mold, and bond them at 6MPa for 50 minutes to obtain the semi-finished product; A5. Immerse the semi-finished product in 25# transformer oil for 40 minutes at an oil temperature of 60°C. Take it out and drain the oil. Wrap it with plastic sheeting and sealing tape. Store it upright in an insulated drying room at a temperature of 50°C and a humidity of 27%.

[0021] Example 3 The difference between this embodiment and the first embodiment is that the method for preparing the insulating cardboard tube 2 includes: A1. Use a groove milling machine to process grooves on both ends of high-density insulation paper to obtain blanks; A2, 0.5kg / m 2 After spraying distilled water on the surface of the blank, wrap it with plastic sheeting and keep it moist for 22 hours; A3. Place the wetted blank into a rounding machine and roll it into a round shape using the upper pressing roller. Repeat the rounding 15 times using the groove as the overlapped part. Place the blank in an aluminum mold with an appropriate diameter and vacuum dry it to obtain a dry blank. The vacuum drying method includes: A31, preheating stage: temperature 100 ℃, vacuum degree 58000Pa, heat preservation 20min; A32, step-by-step transition stage: gradually evacuate to 10000Pa, and keep warm for 20 minutes after each evacuation; A33, high vacuum stage: temperature 125 ° C, vacuum degree 180 Pa, lasting 140 minutes, until the moisture content is less than 1%; A4. Apply epoxy resin glue to the overlapping parts of the dry blanks, fix the overlapping positions with G-type clamps, place them in the bonding machine mold, and bond them at 5Pa for 60 minutes to obtain the semi-finished product; A5. Immerse the semi-finished product in 25# transformer oil for 35 minutes at an oil temperature of 70°C. Take it out and drain the oil. Wrap it with plastic sheeting and sealing tape. Store it upright in an insulated drying room at a temperature of 45°C and a humidity of 26%.

[0022] It should be noted that the wall thickness of the conventional glass fiber tube is 5 mm, while the wall thickness of the insulating cardboard tube 2 in the present invention is 4 mm, and the thickness of the coil stay 3 is 8 mm, so as to improve the internal heat dissipation rate of the coil bobbin 5.

[0023] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A new type of transformer low-voltage coil inner support tube structure, characterized in that: It comprises an insulating cardboard tube (2) sleeved on the outer periphery of an adjustable coil winding mold (1), a coil support bar (3), and an insulating gasket assembly (4); The coil support bar (3) is adhered and fixed to the outer periphery of the insulating cardboard tube (2), a plurality of the coil support bars (3) are provided and are evenly distributed at intervals on the outer periphery of the insulating cardboard tube (2), and the insulating gasket assembly (4) is sleeved on the outer periphery of the coil support bar (3).

2. A novel transformer low-voltage coil inner support cylinder structure according to claim 1, characterized in that: The preparation method of the insulating cardboard tube (2) comprises: A1. Use a groove milling machine to process grooves on both ends of high-density insulation paper to obtain blanks; A2, 0.4-0.5kg / m 2 After spraying distilled water on the surface of the blank, wrap it with plastic cloth and keep it moist for 16-24 hours; A3. Place the moistened blank into a rounding machine and roll it into a round shape using the upper roller. Repeat the rounding process 10-15 times using the groove as the overlapped part. Place the blank in an aluminum mold with an appropriate diameter and vacuum dry it to obtain a dry blank. A4. Apply epoxy resin glue to the overlapping parts of the dry blanks, fix the overlapping positions with G-type clamps, place them in the bonding machine mold, and bond them at 4-6MPa for 50-60 minutes to obtain the semi-finished product; A5. Immerse the semi-finished product in 25# transformer oil for 30-40 minutes at an oil temperature of 60-80°C. Take it out and drain the oil. Wrap it with plastic sheeting and sealing tape and store it upright in a heat-insulating drying room with a temperature of 40-50°C and a humidity of ≤30%.

3. A novel transformer low-voltage coil inner support cylinder structure according to claim 2, characterized in that: The vacuum drying method in A3 includes: A31, preheating stage: temperature 98-102 ℃, vacuum degree 55000-65000Pa, keep warm for 20min; A32, step-by-step transition stage: gradually evacuate to 10000Pa, and keep warm for 20 minutes after each evacuation; A33. High vacuum stage: temperature 125°C, vacuum degree below 200Pa, lasting 100-140 minutes, until the moisture content is less than 1%.

4. The novel transformer low-voltage coil inner support cylinder structure according to claim 1 is characterized in that: The insulating gasket assembly (4) comprises two adhesive strips (401), and a plurality of insulating gaskets (402) are adhered and fixed between the two adhesive strips (401).

5. The novel transformer low-voltage coil inner support cylinder structure according to claim 4 is characterized in that: The coil support bar (3) is arranged in a T-shape, and a slot (403) is provided on one side of the insulating gasket (402), and the slot (403) is used in conjunction with the coil support bar (3).

6. The novel transformer low-voltage coil inner support cylinder structure according to claim 5 is characterized in that: The adhesive strip (401) is adhered and fixed to the outer periphery of the insulating cardboard tube (2).

7. The novel transformer low-voltage coil inner support cylinder structure according to claim 6 is characterized in that: A plurality of coil bobbins (5) are wound around the outer peripheries of the plurality of coil stays (3).

8. The novel transformer low-voltage coil inner support cylinder structure according to claim 7 is characterized in that: The insulating gasket (402) is arranged between two adjacent coil windings (5).

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