PL204156B1 - Active welding filter - Google Patents

Description

Description of the invention

The subject of the invention is an active welding filter, intended to be mounted in welding shields that protect the eyes, face, neck and ears of the welder against harmful radiation and splashes of molten metal or slag generated during welding.

Welding filters are designed to be mounted in welding shields that protect the eyes, face, neck and ears of the welder against harmful radiation and splashes of molten metal or slag formed during welding. Both passive and active filters are used. Passive welding filters are made of mineral glass or body-colored plastics.

Currently produced active welding filters consist of liquid crystal systems, polarizers, interference filters, power modules (batteries or solar cells), welding arc radiation detectors and electronic systems.

Welding filters should be made of a material that reflects or absorbs ultraviolet radiation, intense visible radiation and infrared radiation.

The active welding filter according to the invention consists of a filter system which, counting from the side of the welding arc, consists of:

- soda or quartz glass lens, UV transmitting

- a photochromic filter induced by radiation from the welding arc,

- a band interference filter transmitting visible radiation from the 530 nm - 570 nm band or optionally from the 520 nm - 580 nm band;

- a glass or plastic passive absorption filter which absorbs infrared radiation;

- an interference filter that blocks ultraviolet radiation and infrared radiation.

The photochromic filter is a solution of a photochromic dye selected from the group of spirobenzopyranindolines, preferably 1 ', 3', 3'-trimethyl-6-nitrospiro [2H-1-benzopyran-2,2'-indoline], in a non-polar solvent with a concentration of 0.015-0.025 g dye \ ml of solvent. The photochromic dye solution changes the light transmission coefficients as a result of the photochromic reaction, under the influence of the absorption of ultraviolet radiation generated during electric welding. As the non-polar solvent, ethyl acetate or acetone is preferably used. An interference filter that blocks ultraviolet and infrared radiation is applied to a glass or plastic passive absorbing filter in the form of inertial coatings. The following were used as materials for the layers:

TiO2 - H - material with a high refractive index and

SiO2 - L - material with a low refractive index.

The layers were deposited using the high-vacuum surfacing technique with the use of an electron gun.

As a band-pass interference filter passing visible radiation from the 530 nm -570 nm band or optionally from the 520 nm -580 nm band, a glass or plastic passive filter was used as a substrate for applying interference coatings.

It is most preferred that all filters, with the exception of the photochromic filter, constitute the walls of the cuvette in which the dye solution is placed.

The transmittance of the photochromic filter is defined by the properties of the excited dye. The band of maximum attenuation in the excited state is consistent with the maximum sensitivity of the eye. The spectral transmission curve of the dye with the spirobenzopyranindoline structure in the excited state is shown in Figure 1.

PL 204 156 B1

Diagram 1. Diagram of dye absorption in the excited state

Active welding filters made with the use of a photochromic dye according to the invention:

- have a response time of less than 0.5 ms, in the temperature range from -10 ° C to + 55 ° C,

- they change the light transmission coefficients automatically depending on the welding current intensity in the range from 3% to 0.001%,

- transmit less than 0.00003% of harmful ultraviolet radiation at a wavelength of 313 nm 365 nm

- they transmit on average less than 0.01% of infrared radiation for the range from 780 nm to 1400 nm.

The active welding filter according to the invention is shown in cross-section in the drawing.

Example I. In order to manufacture welding photochromic filters, the following steps must be taken:

1. Cutting out the elements of the sodium glass cuvette

Cut 1 mm thick soda glass plates with dimensions of 110 mm by 90 mm (with an accuracy of 0.5 mm) on a machine with a silicon carbide cutting element.

The back wall of the filter is a soda glass plate with applied interference layers. The anti-glare layer of the absorption filter should be outside the cuvette. The side walls of the cuvette are glass strips 3 mm wide and 1 mm thick.

2. Preparation of cuvettes with a photochromic dye solution

Active filter - the cuvette should be made of glued glass plates:

- Outer sodium glass filter disc, 1 mm thick;

- The side walls of the filter are also made of glass with a thickness of 1 mm or 1.5 mm;

- Sodium glass back wall incorporating an infrared absorber on the surfaces of which interference layers are applied.

3. Gluing the cuvette elements

Before applying the adhesive to the surface, place the cuvette elements in the holder. Leave two 1 mm wide openings in the upper part of the cuvette for filling the cuvette.

PL 204 156 B1

For gluing the surface of glass tiles, use, for example, glues cured with ultraviolet radiation.

4. Preparation of the dye solution

Weigh 25 g of dye with an accuracy of 0.1 g using a technical balance. Using a measuring cylinder, measure 1 dm ³ of ethyl acetate (analytical grade). Dissolve the dye in ethyl acetate using an ultrasonic stirrer. Stir the solution for 30 minutes in a 25 ° C bath. Then pass nitrogen through the solution to remove residual oxygen.

5. Filling the cuvette

Fill cuvettes with a solution of 1 ', 3', 3'-trimethyl-6-nitrospiro [2H-1-benzopyran-2,2'-indoline] in ethyl acetate. Remove the air from the cuvette using an IS-1K ultrasonic stirrer with an ultrasonic frequency of 35 kHz. The filling is carried out under nitrogen atmosphere.

Perform ultrasonic agitation for 5 minutes with bath temperature of 25 ° C.

Removal of air from the solvent significantly increases the resistance of the filters to ultraviolet radiation.

6. Sealing cuvettes

Seal the cuvette with the dye solution with a two-component adhesive containing polyepoxy resin, e.g. Super Epox type. Allow the litter box to dry for 2 hours.

7. Production of interference coatings for active welding filters

The set of interference filters that make up the welding filter includes:

- an interference filter that blocks UV and NIR radiation

- a band interference filter transmitting visible radiation from the 530-570 nm band or optionally from the 520-580 nm band.

The UV-NIR interference filter blocks the ultraviolet and infrared bands, but cooperating with the dye filter does not give the necessary reduction in the transmittance in the ranges 400 nm-500 nm and 600-800 nm. Interference filters are designed to accomplish this task.

The transmission characteristics of these filters are shown in Figures 2 and 3.

Diagram 2. Transmission characteristic of a 40 nm wide bandpass filter

PL 204 156 B1

Diagram 3. Transmission characteristics of a 60 nm bandpass filter

The following were used as layer materials to make these filters:

- TiO2 - H - material with a high refractive index

- SiO2 - L - material with a low refractive index.

The layers were applied by means of high vacuum vaporization with the use of an electron gun.

Passive filter that absorbs infrared radiation

As a passive filter that absorbs infrared radiation, use an ATHERMAL filter with protection class 3, with an average IR transmission factor of 0.75%. This filter is a substrate for applying interference coatings.

An alternative solution may be the use of a filter made of mass-colored polycarbonate with an infrared absorber N, N, N ', N'-Tetrakis- (p-di-n-butylaminophenyl) -p-benzoquinone-bisimmonium hexafluoroantimonate with a concentration from 0.432 g to 0.504 g per 1000 g of macrolon.

The design record of the blocking interference filter is shown in Table 1

Blocking filter - construction record λ = 500 nm

Sub- (1.6H 1.6L) 7 2.196H 1L0.594H 0.654L (1.07H 1.07L) 6 0.816H 1.552L-Air nH = 2.20 nL = 1.46

T a b e l a 1

No Mat. L.T. T.G k (λ / 4) λ - n 1 2 3 4 5 6 1 H. 45 1 1.070 691 2 L. 44 1 1.070 3 H. 45 1 1.070

PL 204 156 B1 cont. table 1

1 2 3 4 5 6 4 L. 44 1 1.070 5 H. 45 1 1.070 6 L. 44 1 1.070 7 H. 45 2 1.070 8 L. 44 2 1.070 9 H. 45 2 1.070 10 L. 44 2 1.070 11 H. 45 2 1.070 12 L. 44 2 1.070 13 H. 45 3 1.070 14 L. 44 3 1.070 15 H. 45 3 1.468 16 L. 44 3 0.669 17 H. 45 3 0.397 18 L. 44 3 0.437 19 H. 45 4 1.124 440 twenty L. 44 4 0.583 21 H. 45 4 1.124 22 L. 44 4 0.583 23 H. 45 5 1.124 24 L. 44 5 0.583 25 H. 45 5 1.124 26 L. 44 5 0.583 27 H. 45 5 1.124 28 L. 44 5 0.583 29 H. 45 6 1.124 thirty L. 44 6 0.583 31 H. 45 6 0.857 32 L. 44 6 1.63

The design of the bandpass filter is presented in Table 2

Bandpass filter 530 - 570 nm - construction notation λ = 560nm

Sub - (1H 1L 1H 2L 1H 1L 1H 1L) 4 - Air nH = 2.20 nL = 1.46

PL 204 156 B1

T a b e l a 2

No Mat. L.T. T.G k (λ / 4) λ - n 1 H. 45 1 1.070 2 L. 44 1 1.070 498 3 H. 45 1 1.070 4 L. 44 1 2,140 5 H. 45 2 1.070 6 L. 44 2 1.070 7 H. 45 2 1.070 8 L. 44 2 1.070 9 H. 45 3 1.070 10 L. 44 3 1.070 11 H. 45 3 1.070 12 L. 44 3 2,140 13 H. 45 2 1.070 14 L. 44 2 1.070 15 H. 45 2 1.070 16 L. 44 2 1.070 17 H. 45 4 1.070 18 L. 44 4 1.070 19 H. 45 4 1.070 twenty L. 44 4 2,140 21 H. 45 5 1.070 22 L. 44 5 1.070 23 H. 45 5 1.070 24 L. 44 5 1.070 25 H. 45 6 1.070 26 L. 44 6 1.070 27 H. 45 6 1.070 28 L. 44 6 2,140 29 H. 45 4 1.070 thirty L. 44 4 1.070 31 H. 45 4 1.070 32 L. 44 4 1.070

The notation of the construction of the bandpass filter is presented in Table 3.

Sub- (1H 2L 1H 1L 1H 1L) 4 - Air nH = 2.20 nL = 1.46

PL 204 156 B1

T a b e l a 3

No Mat. L.T. T.G k (λ / 4) λ - n 1 H. 45 1 1.070 2 L. 44 1 2,140 498 3 H. 45 2 1.070 4 L. 44 2 1.070 5 H. 45 2 1.070 6 L. 44 2 1.070 7 H. 45 3 1.070 8 L. 44 3 2,140 9 H. 45 2 1.070 10 L. 44 2 1.070 11 H. 45 2 1.070 12 L. 44 2 1.070 13 H. 45 4 1.070 14 L. 44 4 2,140 15 H. 45 5 1.070 16 L. 44 5 1.070 17 H. 45 5 1.070 18 L. 44 5 1.070 19 H. 45 6 1.070 twenty L. 44 6 2,140 21 H. 45 5 1.070 22 L. 44 5 1.070 23 H. 45 5 1.070 24 L. 44 5 1.070

Investigation of light transmission coefficients

Filter type Bright condition F40-3Et Light transmission factor% Level of security 1.724 5

The obtained value is within the limits specified for the protection level 5. The tests carried out in the conditions of exposure to the radiation of the arc formed during welding with a coated electrode also showed sufficient visibility of the welded object, enabling welding requiring precision, min. welding of small parts.

The values of the light transmission coefficient of photochromic welding filters determined for electric welding with a coated electrode with a diameter of 3 mm - distance from the welding source 0.3 m -, welding current 120 A.

Filter type Dark state F40-3Et Light transmission factor% Standard deviation Level of security 0.0215 0.0084 10

PL 204 156 B1

The obtained values are in accordance with the recommendations for the selection of welding filters for welding with a coated electrode with a current strength from 100 A to 125 A, specified in the PN-EN 169: 2004 standard.

Claims (1)

Active welding filter, characterized in that, from the side of the welding arc, it consists of a lens made of sodium or quartz glass / 1, a photochromic filter / 2 /, a glass or plastic passive absorption filter / 3 /, absorbing infrared radiation, on the inside of which on the surface, there is a band-pass interference filter / 4 / transmitting visible radiation from the 530 nm -570 nm band or optionally from the 520 nm -580 nm band, and on the outer surface an interference filter / 5 / blocking ultraviolet radiation and infrared radiation, the photochromic filter is solution of the photochromic dye selected from the spirobenzopyranindoline group, preferably 1 ', 3', 3'-trimethyl-6-nitrospiro [2H-1-benzopyran-2,2'-indoline], in a non-polar solvent with a concentration of 0.015 - 0.025 g of dye / ml the solvent and the nonpolar solvent is preferably ethyl acetate or acetone.