CN201427226Y

CN201427226Y - Air blast nozzle for laser cutting machines

Info

Publication number: CN201427226Y
Application number: CN 200920306841
Authority: CN
Inventors: 宫长海; 吴庆隆
Original assignee: BOYE LASER APPLIED TECHNOLOGY Co Ltd
Current assignee: BOYE LASER APPLIED TECHNOLOGY Co Ltd
Priority date: 2009-07-24
Filing date: 2009-07-24
Publication date: 2010-03-24
Anticipated expiration: 2019-07-24

Abstract

The utility model discloses an air blast nozzle for laser cutting machines, which comprises an air inlet (2), an air tap body (1) and an air outlet (3), wherein the air tap body has an initial section(1) and a conical contraction section (m). The an air blast nozzle for laser cutting machines is characterized in that the air inlet (2) is tangent to the inner cavity wall of the air tap body (1), the center line of the air inlet (2) and the horizontal line of the air tap body (1) form an included angle (a), and the air outlet (3) has a trumpet-shaped expansion section (d) which is communicatedwith the conical contraction section (m) through a transition section (n). The air blast nozzle with the structure can lead the airflow of the air inlet to speed up whirlingly along the inner cavity wall of the air tap body, and the airflow can be accelerated to supersonic speed after passing through the contraction section and a bell mouth, thus the air blast nozzle can be applied to laser cutting machines for the cutting of materials with large thickness, and the cutting speed and quality are also enhanced.

Description

The air nozzle that is used for laser cutting machine

Technical field

The utility model belongs to the laser engine field, particularly be nozzle on a kind of laser cutting machine.

Background technology

Along with developing rapidly of science and technology and succeeding in developing of superpower laser, the cutting processing of nonmetallic materials more and more widely requires the thickness of cutting material increasing, and the requirement of precision, speed and quality is also more and more higher.All be to use traditional nozzle and when cutting uses on these laser instruments, thereby can't satisfy the requirement of use.The structure of conventional spout is such: comprise air inlet, current stabilization district and contraction section and gas outlet, the gas outlet is a common pore, no special construction, the air-flow accelerating region of this traditional nozzle has only contraction section, personnel in the present technique field are called the contraction type nozzle, the shortcoming of this conventional spout is, after high pressure draught enters nozzle, air-flow is an infinite space jet turbulent condition, the air-flow that enters produces shock wave, the harm of this shock wave in the flow field is: when laser passed the flow field of shock wave, its refractive index changed, and caused focal position of laser to change, the ablation energy and the width of slit that are laser all are affected, make the bad stability of cutting performance simultaneously, cutting efficiency descends, the cut quality variation.Eliminate shock wave, guarantee the air-flow uniformity, that is to say that changing air-flow into laminar flow by turbulent flow just can address this is that; And the nozzle of this structure is to shrink shape, and the speed of its air-flow can only reach subsonic speed, and air velocity is not enough, the flue dust and the slag that produce in the time of can't clearing up the laser cutting machine cutting fast, thereby just can't cut the bigger material of thickness.

The utility model content

In view of the deficiency that background technology exists, the technical problems to be solved in the utility model provides and a kind ofly changes air-flow into laminar flow by turbulent flow, and air velocity is accelerated to the ultrasonic air nozzle that is used for laser cutting machine.

For this reason, the utility model takes following technical scheme to realize: a kind of air nozzle that is used for laser cutting machine, comprise air inlet, valve body and gas outlet, described valve body has The initial segment and taper contraction section, the internal chamber wall that it is characterized in that described air inlet and described valve body is tangent, and the center line of air inlet becomes one 5 ~ 10 ° of described expansion segments to be communicated with described contraction section through changeover portion with the horizontal line of described valve body.

In the utility model, according to aerodynamics, the accelerator theory of circling round, confined space jet and wall-attached jet theory, because air inlet and valve body have angle, make the high pressure draught that enters air nozzle, the acceleration again of the circle round acceleration and the contraction section of process The initial segment, make air-flow accelerate to lower supersonic speed, pass through changeover portion and expansion segment again after, the sectional area of expansion segment increases, flow velocity increases, pressure reduces, and force value levels off to ambient value, and the air-flow behind the expansion segment of flowing through can not produce sudden change, air-flow is than uniformity, can not produce shock wave, reach satisfied supersonic speed, make the air-flow of ejection all be converted into kinetic energy, when on laser cutting machine, using, the flue dust and the slag that can be in time produce during with cutting in time blow away, and therefore, can cut the bigger material of thickness.

Description of drawings

Further describe relevant details of the present utility model below more in conjunction with the accompanying drawings.

Fig. 1 is a structure chart of the present utility model;

Fig. 2 is the cutaway view of the utility model Fig. 1 along A-A;

Fig. 3 is the enlarged drawing at the utility model Fig. 1 M place;

The schematic diagram that Fig. 4 changes from big to small for the utility model valve cross section;

The schematic diagram that Fig. 5 changes from small to large for the utility model valve cross section;

Fig. 6 is the schematic diagram that the utility model valve transition section changes.

The specific embodiment

With reference to accompanying drawing, this air nozzle that is used for laser cutting machine, comprise air inlet 2, valve body 1 and gas outlet 3, described valve body 1 has The initial segment 1 and taper contraction section m, as shown in Figure 2 in, described air inlet 2 is tangent with the internal chamber wall of described valve body 1, and the center line of air inlet 2 becomes one 5 ~ 10 ° angle α with the horizontal line of described valve body, angle in the present embodiment adopts 5 °, and the horizontal line in the utility model refers in the accompanying drawing, the horizontal direction line that figure is placed; Described gas outlet 3 has and is trumpet-shaped expansion segment d, and described expansion segment d is communicated with described contraction section m through changeover portion n.The air nozzle of this structure is called the supersonic jet mouth that circles round, and according to the description of said structure as can be known, this air nozzle includes four sections: circle round and quicken The initial segment 1, circle round and quicken contraction section m, constant speed changeover portion n, supersonic speed expansion segment d.

The acceleration The initial segment 1 of circling round makes the air-flow that enters nozzle with the design of the air inlet 2 that becomes angle, eliminate the infinite space jet, realize confined space rotating jet and wall-attached jet, become stable air-flow, eliminated the recirculating zone that exists in the background technology, adopted and the air-flow incidence angle at the downward axial advancement angle of valve body horizontal direction and the air inlet that is provided with along the nozzle chamber tangential direction, after high pressure draught enters the flow field like this, just form the laminar jet air-flow that circles round and descend along the air nozzle internal chamber wall, realized the downward continous-stable air-flow of acceleration that revolves faster and faster, this stabilized uniform air-flow stream more is all the more fast, formed cyclotron, this attached wall air-flow that circles round has been eliminated the infinite space jet simultaneously, realized confined space jet and eliminated shock wave, produced and quickened to flow; Because air-flow does not pass laser beam, just do not influence the laser power of laser machine.

The acceleration contraction section m that circles round accelerates to lower supersonic speed with the subsonic flow that circles round in the flow field, becomes to reach satisfied ultrasonic precondition, prepares to quicken again.By the aerodynamics theory, gas along the equation that variable cross-section flows is: 1/AdA/dS=(Ma ²-1) 1/vdv/ds (1) can be drawn between sectional area, flow velocity, the pressure by (1) and to concern, and is as shown in the table:

By the conclusion of gas flow rate equation (1) as can be known: gas is in the subsonic flow zone, and when gas flow through contracted section, its flow velocity increased; Pressure reduces, and makes in the flow field air-flow obtain to quicken to flow, because air-flow is in the attached wall rotary irradiating flow field that is directed downwards with plumb line all the time, individual cyclotron motion is arranged again again, so obtains dual acceleration.Reach supersonic speed, for quickening to provide precondition again than low mach.

Constant speed changeover portion n is that flow velocity, the pressure with gas all remains unchanged substantially, has the transition stage of guide functions, and its length is very little, and diameter is also less, can reduce air consumption.

Supersonic speed expansion segment d: the supersonic speed expansion segment is to quicken just arriving ultrasonic air-flow again, does not produce sudden change, meets the requirements of Mach number, i.e. MA=1.1 ~ 2.

According to aerodynamics, the conclusion of fluid air flow equation (1): supersonic airstream, when the interface of flowing through enlarged, flow velocity increased, and pressure reduces.Air-flow velocity is quickened once again, reach satisfied Mach number, because pressure reduces, make its pressure approach the pressure of environment, and make the air-flow that flows out air nozzle can not produce sudden change, and the supersonic speed gyration airflow of the continous-stable of reentrying, the air-flow of rotation all is converted into kinetic energy at a high speed.The air-flow of this high rotation had both improved the cutting speed of laser cutting machine, and gas particles and the slag that cutting material is produced is blown away very soon again, improved the cutting power of laser cutting machine laser; High speed kinetic energy air-flow is taken away the high heat at joint-cutting place again, and the joint-cutting temperature is reduced, and has reduced the problem of joint-cutting jaundice.

Therefore, air nozzle of the present utility model, the border of gas flowfield ejection is neat, air-flow is uniform and stable, do not have shock wave, the air-flow of ejection has reached satisfied bigger Mach number, is used on the laser cutting machine, during the cutting non-metal material, cutting speed obviously improves, and cutting thickness increases, and cut quality is significantly improved, the temperature of cut place reduces, and the refuse (comprising flue dust, waste gas, waste residue, slag etc.) at cutting seam place is discharged and is more prone to; Provide effective method for eliminating laser cutting dry goods material this difficult problem of turning to be yellow.

Claims

1. air nozzle that is used for laser cutting machine, comprise air inlet (2), valve body (1) and gas outlet (3), described valve body has The initial segment (l) and taper contraction section (m), it is characterized in that described air inlet (2) is tangent with the internal chamber wall of described valve body (1), and the horizontal line of the center line of air inlet (2) and described valve body (1) have angle (α), described gas outlet (3) has and is trumpet-shaped expansion segment (d), and described expansion segment (d) is communicated with described contraction section (m) through changeover portion (n).

2. the valve that is used for laser cutting machine according to claim 1, the size that it is characterized in that described angle (α) is 5 ~ 10 °.