CN111690929B

CN111690929B - Laser cladding head

Info

Publication number: CN111690929B
Application number: CN202010619207.2A
Authority: CN
Inventors: 张辉; 肖光春; 赵伟; 白雪
Original assignee: Qilu University of Technology
Current assignee: Qilu University of Technology
Priority date: 2020-07-01
Filing date: 2020-07-01
Publication date: 2022-03-29
Anticipated expiration: 2040-07-01
Also published as: CN111690929A; CN114592189A; CN114592189B

Abstract

The invention discloses a laser cladding head which comprises a nozzle body, wherein the nozzle body is of a hollow cylinder structure with openings at two ends, the upper end and the lower end of an inner cavity of the nozzle body are respectively a cylindrical cavity and a conical cavity which are communicated, the opening at the lower end of the nozzle body is smaller than the opening at the upper end, the upper end of the nozzle body is hermetically connected with a condensing lens, a powder channel and a protective gas channel are arranged on the nozzle body, the powder channel comprises a main channel and a plurality of feeding channels, and a switching device for switching the communication between the feeding channels and the main channel is arranged on the nozzle body. According to the invention, the plurality of feeding channels can be independently opened, so that the alternative filling of various powders is realized, the rapid switching of the filling of the powders with different particle sizes is realized according to the cladding requirement, the filling and replacing of the powders without shutdown is realized, and the processing continuity is ensured.

Description

Laser cladding head

Technical Field

The invention relates to the technical field of laser cladding, in particular to a laser cladding head.

Background

The laser cladding technology is characterized in that a high-energy laser beam is used for melting an added material on the surface of a base material to form a high-performance cladding layer which is in metallurgical bonding with the base material. The laser cladding complete equipment is very expensive, the cost of cladding materials becomes a problem to be considered in a key way, and the preparation of a cladding layer with low price and excellent performance becomes a key point for the wide application of the technology. The Fe-based cladding powder has obvious price advantage, but the corrosion resistance of the Fe-based cladding powder needs to be improved. The VC reinforced Fe-based composite laser cladding layer has better wear resistance, but the corrosion resistance is relatively poor. The corrosion potential of the Fe matrix can be increased by alloying, but this results in an increase in the powder cost. The corrosion resistance and the toughness of the VC/Fe cladding layer can be obviously improved by regulating the particle size of the powder and refining the cladding layer structure by the cladding process. However, when laser cladding is performed, the existing nozzle only has one powder feeding channel, namely, only single powder can be filled during processing, and powder replacement in the cladding process, namely powder replacement with different particle sizes, is not facilitated, so that a laser cladding head capable of replacing and filling powder at any time in the cladding process needs to be developed.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide a laser cladding head which can replace powder in the cladding process.

In order to achieve the purpose, the invention provides the following technical scheme: the utility model provides a laser cladding head, includes the shower nozzle body, the shower nozzle body is both ends open-ended hollow cylinder structure, the inner chamber upper end and the lower extreme of shower nozzle body are the cylindricality cavity and the toper cavity of intercommunication respectively, the lower extreme opening of shower nozzle body is less than the upper end, the upper end sealing connection of shower nozzle body has condensing lens, is provided with powder passageway and protective gas passageway on the shower nozzle body, the powder passageway include main entrance and a plurality of feedstock channel, the shower nozzle body on be provided with and be used for switching feedstock channel and the communicating auto-change over device of main entrance.

In order to ensure that the powder can be dispersed more uniformly and can be gathered to a laser irradiation area, the plurality of feeding channels are a plurality of groups of annular powder feeding grooves arranged in the side wall of the cylindrical inner cavity of the nozzle body, a shielding ring is arranged on the side wall of the cylindrical inner cavity of the nozzle body in an axially sealed sliding manner, a through hole is arranged on the circumferential wall of the shielding ring, a piston cavity is arranged inside the side wall of the nozzle body, a cylindrical piston is arranged in the piston cavity in a sealed sliding manner, the cylindrical piston is fixedly connected with the shielding ring through a connecting rod, one end of the piston cavity is provided with an air inlet channel communicated with an external air source, the other end of the piston cavity is provided with an air vent, a spring is arranged between the piston cavity and the cylindrical piston, the movement direction of the cylindrical piston is consistent with the axial direction of the nozzle body, and when the through hole of the shielding ring is communicated with one group of the powder feeding grooves, the rest powder feeding grooves are shielded and sealed by the outer circumferential wall of the shielding ring, the main channel is a cylindrical cavity and a conical cavity of the sprayer body, each powder filling groove is provided with a powder inlet arranged outside the sprayer body, the protective gas channel comprises a first protective gas channel and a second protective gas channel, a gas outlet of the first protective gas channel is formed in the inner wall of the cylindrical cavity of the sprayer body and is located between the condensing lens and the powder filling groove at the highest position, a gas outlet of the second protective gas channel is formed in the lower end face of the sprayer body, and gas inlets of the first protective gas channel and the second protective gas channel are located outside the sprayer body.

In order to facilitate installation of the condenser lens, a step hole is formed in an opening at the upper end of the spray head body, the condenser lens is arranged at the step of the step hole, and a pressing ring is arranged on the inner wall of the spray head body above the condenser lens through threads.

In order to facilitate processing, the powder filling groove comprises an annular outer groove and an annular inner groove which are formed in the surfaces of the inner wall and the outer wall of the spray head body, the outer groove is communicated with the inner groove through a plurality of groups of through holes, a powder inlet outer cover is arranged outside the outer groove in a sealing and covering mode, and a powder inlet communicated with the outer groove is formed in the powder inlet outer cover.

For the convenience of processing, the outer wall upper portion of shower nozzle body sets up annular first air guide groove, first air guide groove and first protective gas passageway intercommunication, first air guide groove outside sealing cover has first outer cover of admitting air, first outer cover of admitting air is provided with the air inlet with first air guide groove intercommunication.

For the convenience of processing, the outer wall downside of shower nozzle body sets up annular second air guide groove, second air guide groove and second protective gas passageway intercommunication, second air guide groove outside sealing cover has the second dustcoat of admitting air, the second dustcoat of admitting air is provided with the air inlet with second air guide groove intercommunication.

In order to improve the cladding effect and reduce the damage of heat to the nozzle body, a drainage cavity is arranged in the side wall of the upper end of the nozzle body, a plurality of feeding channels are a plurality of groups of annular powder material filling grooves arranged in the outer side wall of the drainage cavity of the nozzle body, a shielding ring is arranged on the outer side wall of the drainage cavity in an axially sealed sliding manner, a through hole is arranged on the circumferential wall of the shielding ring, a piston cavity is arranged in the outer side wall of the drainage cavity, a cylindrical piston is arranged in the piston cavity in a sealed sliding manner and fixedly connected with the shielding ring through a connecting rod, one end of the piston cavity is provided with an air inlet channel communicated with an external air source, the other end of the piston cavity is provided with an air vent, a spring is arranged between the piston and the cylindrical piston, the movement direction of the cylindrical piston is consistent with the axial direction of the nozzle body, and when the through hole of the shielding ring is communicated with one group of powder material filling grooves, the other powder filling grooves are sealed by the outer circumferential wall of the shielding ring, the main channel is a drainage cavity and a gathering channel extending from the lower part of the drainage cavity to the lower end face of the sprayer body, the drainage cavity is annular, the upper end of the gathering channel is annular, the lower end of the gathering channel is divided into a plurality of gas outlets, the axes of all the gas outlets of the gathering channel are intersected at the same point of the axis of the conical cavity of the sprayer body, the point is positioned at the lower side of the sprayer body, each powder filling groove is provided with a powder inlet arranged outside the sprayer body, the protective gas channel comprises a first protective gas channel and a second protective gas channel, the gas outlet of the first protective gas channel is arranged on the outer wall of the drainage cavity of the sprayer body and between the condensing lens and the powder filling groove at the highest position, and the gas outlet of the second protective gas channel is arranged on the lower end face of the sprayer body, the gas outlet of the second protective gas channel is positioned at the periphery of the gas outlet of the gathering channel, and the gas inlets of the first protective gas channel and the second protective gas channel are positioned outside the sprayer body.

In order to prolong the service life of the spray head body, a water-cooling circulation channel is arranged in the side wall of the lower end of the spray head body.

The spray head body comprises an upper part and a lower part which are made of different materials and are in a split structure. The lower part of the nozzle body is made of a material with heat resistance superior to that of the upper part. Thereby improving the cost performance.

The invention has the beneficial effects that: according to the invention, the plurality of feeding channels can be independently opened, so that the alternative filling of various powders is realized, the rapid switching of the filling of the powders with different particle sizes is realized according to the cladding requirement, the filling and replacing of the powders without shutdown is realized, and the processing continuity is ensured.

Drawings

FIG. 1 is a schematic structural diagram of an embodiment of the present invention;

FIG. 2 is a cross-sectional view of an embodiment of the present invention;

FIG. 3 is an enlarged view of FIG. 2 at A;

FIG. 4 is a cross-sectional view of a second embodiment of the present invention;

in the figure: the powder spraying device comprises a spray head body 1, a second protective gas channel 101, a powder filling groove 102, a drainage cavity 103, a gathering channel 104, a powder feeding outer cover 2, a second air inlet outer cover 3, a first air inlet outer cover 4, a condensing lens 5, a pressing ring 501, a shielding ring 6, a cylindrical piston 601 and a spring 602.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

For example, referring to fig. 1-3, the present embodiment includes a nozzle body 1, the nozzle body 1 is a hollow cylinder structure with two open ends, the upper end and the lower end of the inner cavity of the nozzle body 1 are respectively a communicated cylindrical cavity and a communicated conical cavity, the lower end opening of the nozzle body 1 is smaller than the upper end, the cylindrical inner cavity of the nozzle body 1 is axially provided with a plurality of groups of annular powder material filling grooves 102, the cylindrical inner cavity of the nozzle body 1 is axially and hermetically slidably provided with a shielding ring 6, the circumferential wall of the shielding ring 6 is provided with a through hole, when the through hole of the shielding ring 6 is communicated with one group of powder material filling grooves 102, the rest powder filling grooves 102 are sealed by the outer circumferential wall of the blocking ring 6, the opening at the upper end of the spray head body 1 is hermetically provided with a condensing lens 5, the side wall of the spray head body 1 between the condensing lens 5 and the highest powder filling groove 102 is provided with a through air inlet, and the opening at the lower end of the spray head body 1 is provided with a plurality of groups of second protective gas channels 101 with the lower ends inclined towards the axis.

A step hole is formed in an opening at the upper end of the spray head body 1, the condensing lens 5 is arranged at the step of the step hole, and a pressing ring 501 is arranged on the inner wall of the spray head body 1 above the condensing lens 5 through threads;

the compression ring 501 is connected through threads, and meanwhile, a sealing gasket and a gasket are arranged between the condensing lens 5 and the step surface, so that the sealing between the condensing lens 5 and the inner cavity of the nozzle body 1 is realized, and the focal position of the condensing lens 5 is adjusted.

The powder filling groove 102 comprises an annular outer groove and an annular inner groove which are formed in the surfaces of the inner wall and the outer wall of the spray head body 1, the outer groove and the inner groove are communicated through a plurality of groups of through holes, a powder inlet outer cover 2 is hermetically covered outside the outer groove, and the powder inlet outer cover 2 is provided with a powder inlet communicated with the outer groove;

through the combination of the powder feeding outer cover 2 and the outer groove, powder can be circularly distributed on the outer side of the spray head body 1, so that circumferential feeding is realized, and the phenomenon that powder is deviated to one side in the spray head is avoided.

The outer wall upside of shower nozzle body 1 sets up annular air guide groove, and air guide groove passes through first protective gas passageway intercommunication with the inlet port on the shower nozzle body 1 lateral wall, and air guide groove outside sets up sealed the covering and sets up first outer cover 4 that admits air, and first outer cover 4 that admits air is provided with the air inlet with air guide groove intercommunication.

The outer wall downside of shower nozzle body 1 sets up annular air guide groove, air guide groove and second protective gas passageway 101 intercommunication, and air guide groove external seal covers and sets up second outer cover 3 that admits air, and second outer cover 3 that admits air is provided with the air inlet with air guide groove intercommunication. The gas outlet of the second shielding gas passage 101 is provided on the lower end surface of the shower head body 1.

A piston cavity is arranged in the side wall of the spray head body 1, a cylindrical piston 601 is arranged in the piston cavity in a sealing sliding manner, the cylindrical piston 601 is fixedly connected with the shielding ring 6 through a connecting rod, an air inlet channel communicated with an external air source is arranged at one end of the piston cavity, a spring 602 is arranged between the other end of the piston cavity and the cylindrical piston 601 along the relative movement direction, and the movement direction of the cylindrical piston 601 is consistent with the axial direction of the spray head body 1; the end of the piston cavity in which the spring 602 is disposed is also provided with an air vent for facilitating movement of the cylindrical piston 601.

Through the adjustment of the air pressure in the air inlet channel, the thrust applied to one end of the cylindrical piston 601 is changed, and the relationship between the thrust and the spring force generated by the deformation of the spring 602 is changed, so that the cylindrical piston 601 is positioned at different positions in the piston cavity, the shielding ring 6 is positioned at different positions in the cylindrical cavity, different powder filling grooves 102 are communicated, and the conversion between different powder filling is realized.

When in use: the air inlet of the first air inlet outer cover 4 is communicated with an external high-pressure protective air source, so that high-pressure air flow is introduced into the air inlet, the high-pressure air flow is quickly discharged from an opening at the lower end of the sprayer body 1, powder in the powder filling groove 102 in an open state is wrapped and held, when powder needs to be replaced, the air pressure in an air inlet channel communicated with the piston cavity is changed, namely, the thrust of air to the cylindrical piston 601 is changed, the cylindrical piston 601 drives the shielding ring 6 to change the position, at the moment, the spring 602 deforms, the generated elastic force is also changed, when the elastic force is the same as the thrust force, the cylindrical piston 601 and the shielding ring 6 stop moving, the originally opened powder filling groove 102 is shielded, and a new powder filling groove 102 is opened, so that the function of replacing and filling powder is realized.

Meanwhile, the second gas inlet outer cover 3 is communicated with a gas source device of protective gas, so that the protective gas guided by the second protective gas channel 101 directly acts near the cladding point, and the processing quality of the cladding point is ensured.

Example two

As shown in fig. 4, the difference between the present embodiment and the second embodiment lies in that a drainage cavity 103 is disposed in the sidewall of the upper end of the nozzle body 1, a powder filling groove 102 is disposed in the sidewall of the drainage cavity of the nozzle body 1, a shielding ring 6 is mounted on the sidewall of the drainage cavity, a piston cavity is also disposed inside the sidewall of the drainage cavity, a converging channel 104 is further disposed on the nozzle body 1 and extends from the lower portion of the drainage cavity to the lower end surface of the nozzle body 1, the upper end of the converging channel 104 is in the shape of a ring identical to the drainage channel, the lower end of the converging channel 104 is divided into a plurality of air outlets, the axes of all the air outlets of the converging channel 104 intersect at the same point of the axis of the conical cavity of the nozzle body 1, the point is located at the lower side of the nozzle body 1, the air outlet of the first protective air channel is disposed on the outer wall of the nozzle body 1 and located between the condensing lens 5 and the powder filling groove 102 at the highest position, the gas outlet of the second shielding gas channel 101 is positioned at the periphery of the gas outlet of the gathering channel 104. The annular drainage cavity 103 is beneficial to uniformly mixing powder and gas, and the gathering channel with multiple outlets is beneficial to gathering the powder uniformly dispersed in the gas to a cladding point.

When in use: the air inlet of the first air inlet outer cover 4 is communicated with an external high-pressure protective air source, so that high-pressure air flow is introduced into the air inlet, the high-pressure air flow wraps the powder in the powder filling groove 102 in an open state in a drainage cavity, the powder flows to a cladding point through a gathering channel, cladding is performed under the action of laser, when powder needs to be replaced, the air pressure in the air inlet channel communicated with a piston cavity is changed, namely the thrust of the air on the cylindrical piston 601 is changed, the cylindrical piston 601 drives the shielding ring 6 to change the position, at the moment, the spring 602 deforms, the generated elastic force is also changed, when the elastic force is the same as the thrust, the cylindrical piston 601 and the shielding ring 6 stop moving, the originally opened powder filling groove 102 is shielded, and a new powder filling groove 102 is opened, so that the function of replacing the powder is realized.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. The utility model provides a laser cladding head, includes shower nozzle body (1), shower nozzle body (1) is both ends open-ended hollow cylinder structure, the inner chamber upper end and the lower extreme of shower nozzle body (1) are the cylindricality cavity and the toper cavity of intercommunication respectively, the lower extreme opening of shower nozzle body (1) is less than the upper end, the upper end sealing connection of shower nozzle body (1) has condensing lens (5), is provided with powder passageway and protective gas passageway on shower nozzle body (1), its characterized in that: the powder channel comprises a main channel and a plurality of feeding channels, a switching device used for switching the feeding channels to be communicated with the main channel is arranged on the spray head body (1), the feeding channels are a plurality of groups of annular powder filling grooves (102) arranged in the side wall of the cylindrical inner cavity of the spray head body (1), a shielding ring (6) is arranged on the side wall of the cylindrical inner cavity of the spray head body (1) in a sliding mode along the axial direction in a sealing mode, a through hole is formed in the circumferential wall of the shielding ring (6), a piston cavity is arranged inside the side wall of the spray head body (1), a cylindrical piston (601) is arranged in the piston cavity in a sealing mode in a sliding mode, the cylindrical piston (601) is fixedly connected with the shielding ring (6) through a connecting rod, an air inlet channel communicated with an external air source is arranged at one end of the piston cavity, air holes are formed in the other end of the piston cavity, and a spring (602) is arranged between the piston and the cylindrical piston (601), the moving direction of the cylindrical piston (601) is consistent with the axial direction of the spray head body (1), when the through holes of the shielding ring (6) are communicated with one group of powder filling grooves (102), the rest powder filling grooves (102) are sealed by the outer circumferential wall of the shielding ring (6), the main channel is a cylindrical cavity and a conical cavity of the spray head body (1), each powder filling groove (102) is provided with a powder inlet arranged outside the spray head body (1), the protective gas channel comprises a first protective gas channel and a second protective gas channel, a gas outlet of the first protective gas channel is formed in the inner wall of the cylindrical cavity of the spray head body (1) and located between the condensing lens (5) and the powder filling groove (102) at the highest position, a gas outlet of the second protective gas channel is formed in the lower end face of the spray head body (1), and gas inlets of the first protective gas channel and the second protective gas channel are located outside the spray head body (1).

2. The laser cladding head of claim 1, wherein: the shower nozzle body (1) upper end opening part sets up the step hole, condenser lens (5) set up the step department in the step hole, the shower nozzle body (1) inner wall of condenser lens (5) top is provided with clamping ring (501) through the screw thread.

3. The laser cladding head of claim 2, wherein: the powder filling groove (102) comprises an annular outer groove and an annular inner groove which are formed in the surfaces of the inner wall and the outer wall of the spray head body (1), the outer groove and the inner groove are communicated through a plurality of groups of through holes, a powder inlet outer cover (2) is arranged outside the outer groove in a sealing and covering mode, and a powder inlet communicated with the outer groove is formed in the powder inlet outer cover (2).

4. The laser cladding head of claim 1, wherein: the outer wall upper portion of shower nozzle body (1) sets up annular first air guide groove, first air guide groove and first protective gas passageway intercommunication, first air guide groove outside sealing cover has first outer cover (4) of admitting air, first outer cover (4) of admitting air is provided with the air inlet with first air guide groove intercommunication.

5. Laser cladding head according to any of claims 1-4, wherein: the outer wall downside of shower nozzle body (1) sets up annular second air guide groove, second air guide groove and second protective gas passageway intercommunication, second air guide groove outside sealing covers has second outer cover (3) of admitting air, second outer cover (3) of admitting air is provided with the air inlet with second air guide groove intercommunication.

6. The laser cladding head of claim 5, wherein: and a water-cooling circulation channel is arranged in the side wall of the lower end of the spray head body (1).

7. The laser cladding head of claim 5, wherein: the spray head body (1) comprises an upper part and a lower part which are made of different materials and are in a split structure.