JPS5844217B2 - air curtain nozzle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a nozzle used for air purging for water removal, steam removal, and dust removal, which is used when measuring the moving speed of an object to be measured using a laser.

When measuring the moving speed of a steel plate or the like in a non-contact manner using a laser, if there is water or steam in the optical path between the sensor and the object to be measured or on the surface of the object to be measured, the laser light will be attenuated, making accurate measurement impossible.

The present invention proposes an air curtain nozzle for eliminating such problems.

The invention will be explained below with reference to the drawings.

FIG. 1 is a schematic diagram showing the operation of the present invention.

In the figure, a nozzle 1 is fixed to a pedestal 2 and in contact with a sensor 3, and has a hollow cylindrical shape through which laser light 4 and reflected light 5 pass.

Blow purge air γ from the nozzle 1 to the object to be measured 6,
Water 8 and steam 9 are excluded.

FIG. 2 is a detailed view of the nozzle 1, and 10 is an annular gap 11 for jetting the purge air 7 from the nozzle tip.
The outer wall of the air reservoir 14 and the air intake port 15 constitute the outer wall of the air reservoir 14 and the outer wall of the air reservoir 14 for storing air to make the incoming air 12 and the air 13 have the same pressure and equalize the velocity of the air jetted from the nozzle tip.
The outer cylinder has a hollow cylindrical shape.

Reference numeral 16 is located on the hollow inner surface of the outer cylinder 10, and constitutes a part of the optical path 17 through which the laser beam 4 and the reflected light 5 pass through the hollow cylinder outer surface which constitutes the inner wall of the annular gap 11 and the inner wall of the air reservoir 14. The first inner cylinder is composed of a hollow cylindrical inner surface and a hollow cylindrical inner surface, and has a hollow cylindrical shape.

The first outer cylinder 10 and the first inner cylinder 16 constitute an air intake 15 , an air reservoir 14 , an annular gap 11 , and a part of the optical path 17 . Air 13 is ejected from the annular gap 11 onto the object to be measured 6 through the annular gap 11 to create purge air 7 for removing water and steam.

Next, when the purge air 7 is ejected, the pressure in the optical path 17 decreases, and the purge air 7 becomes a turbulent flow, which destroys the persica.

In order to eliminate this problem, it is necessary to introduce an appropriate amount of auxiliary air 18 into the optical path 17 to prevent pressure drop and prevent persica from falling.

19 has a hollow cylindrical shape, and its outer surface collects air and directs the incoming air 2.
0 and the auxiliary air 18 are at the same pressure, and there are several outflow holes 21 around the circumference.
It is a second inner cylinder that forms part of the optical path 17 and the inner wall of the air reservoir 22 for equalizing the velocity of the auxiliary air 18 coming out of the air reservoir 22 .

A second outer cylinder 23 is located on the outer surface of the second inner cylinder 19 and forms the outer wall of the air reservoir 22 and the air intake port 24, and has a hollow cylindrical shape.

The second large side cylinder 19 and the second outer cylinder 23 constitute an air intake port 24, an air reservoir 22, and an outflow hole 21. Inflow air 20 is introduced from the air intake port 24, passes through the air reservoir 22, and exits from the outflow hole 21. A suitable amount of auxiliary air 18 is blown out, and the optical path 17 is
This serves to prevent a drop in the internal pressure and prevent the purge air 7 from becoming a turbulent flow to maintain the persica.

In addition, when removing water and steam with the purge air 7, steam 9 may be mixed into the purge air 7, so the auxiliary purge air 25 is jetted out at a jetting speed lower than the jetting speed of the purge air 7 to remove steam. Contamination must be prevented.

26 is an outer wall of an annular gap 27 for blowing out auxiliary purge air 25, and an inflow air 28 and air 29 that collect air.
The third outer cylinder constitutes the outer wall of the air reservoir 30 and the air intake port 31 to equalize the pressure and equalize the speed of the air ejected from the annular gap 27, and has a hollow cylindrical shape.

A third inner cylinder 32 is located on the hollow inner surface of the third outer cylinder 26 and forms the inner wall of the annular gap 27 and the air reservoir 30, and has a hollow cylindrical shape.

The third outer cylinder 26 and the third inner cylinder 32 constitute an air intake 31 , an air reservoir 30 , and an annular gap 27 . 29 is ejected to create auxiliary purge air 25 to prevent steam from entering the purge air 7.

As described above, the nozzle of this invention creates a double air curtain through which the laser beam passes, so water and steam can be removed from the optical path between the sensor and the object to be measured, as well as from the surface of the object to be measured. This allows for accurate measurements.

It goes without saying that the air curtain nozzle according to the present invention can not only remove water and steam, but also dust.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing the air purge situation for water removal and steam removal during measurement, and Fig. 2 is a sectional view showing details of the nozzle.
1 is a nozzle, 2 is a pedestal, 3 is a sensor, 4 is a laser beam, 5
is reflected light, 6 is the object to be measured, 7 is purge air (inner annular air curtain), 8 is water, 9 is steam, 10 is the first outer cylinder, 11 is the annular gap, 14 is the air reservoir, 15 is air The intake port, 16 is the first inner cylinder, 17 is the optical path, 18 is auxiliary air, and 25 is auxiliary purge air (outer annular air curtain). In the drawings, the same or corresponding parts are indicated by the same reference numerals. .

Claims (1)

[Claims] 1. A double annular air curtain is created, a path is formed in the inner air curtain for passing the laser beam, and the ejection speed of the inner annular air curtain is higher than the ejection speed of the outer annular air curtain. An air curtain nozzle characterized by having a jetting speed. 2. The air curtain nozzle according to claim 1, wherein auxiliary air is sent to the laser light path in the inner annular air curtain to prevent the air pressure in the light path from decreasing.