CN113198372A

CN113198372A - Powder mixing device, laser cladding powder feeding equipment and laser cladding equipment

Info

Publication number: CN113198372A
Application number: CN202110542128.0A
Authority: CN
Inventors: 黄河; 吴志玮; 蔡国双
Original assignee: Nanjing Huirui Photoelectric Technology Co ltd
Current assignee: Nanjing Huirui Photoelectric Technology Co ltd
Priority date: 2021-05-18
Filing date: 2021-05-18
Publication date: 2021-08-03
Anticipated expiration: 2041-05-18
Also published as: CN113198372B

Abstract

The invention discloses a powder mixing device, laser cladding powder feeding equipment and laser cladding equipment, and relates to the technical field of additive manufacturing to improve the laser cladding effect. The powder mixing device includes: a plurality of defeated powder structures, stirring structure, mixed structure and with stirring structure and mixed structure drive connection's driving piece. The upper surface of the mixing structure is provided with a plurality of protruding structures. The laser cladding powder feeding equipment comprises a powder mixing device, a plurality of powder conveying pipelines, a plurality of powder buckets and a controller. The laser cladding equipment comprises laser cladding powder feeding equipment. The powder mixing device provided by the invention is used for mixing the powder to be mixed conveyed by a plurality of powder conveying pipelines.

Description

Powder mixing device, laser cladding powder feeding equipment and laser cladding equipment

Technical Field

The invention relates to the technical field of additive manufacturing, in particular to a powder mixing device, laser cladding powder feeding equipment and laser cladding equipment.

Background

The laser cladding technology can obviously improve the wear resistance, corrosion resistance, heat resistance, oxidation resistance, electrical appliance characteristics and the like of the surface of the base material, so the laser cladding technology is widely applied. At present, metal powder materials used for laser cladding are generally obtained by a powder process of a traditional alloy ingot. The design of traditional alloy composition mainly aims at traditional metal processing technology such as casting, forging, build-up welding, and laser cladding's physical hot process has great difference with traditional metal processing technology, and the most obvious difference lies in its extremely fast heating and cooling rate to and the hot cold cycle process of relapseing many times, if do not optimize traditional alloy composition, crack defect appears more easily in the cladding in-process. For the requirement of optimizing the alloy composition, sometimes different alloy powder materials need to be mixed, or some single element metal powder is added into one alloy powder material, or some heterogeneous materials are added in order to meet some special performance requirements of a cladding layer, for example, WC ceramic particles are added into nickel-based alloy powder.

In the prior art, if laser cladding is required to be performed by using mixed powder, a premixing method is generally used, namely, the powder is weighed and then mixed according to a certain proportion, a mixer rolls/shakes a powder container to mix the powder, and then the mixed powder is loaded into a powder feeding device of laser cladding equipment. The method is difficult to mix the powder uniformly, and particularly for the powder with large component proportion difference, the element distribution in the final cladding layer is not uniform; and the manual operation steps are more in the mixing process, the measurement precision is easily reduced, and impurities are introduced or powder oxidation pollution is caused. In addition, if the powder composition needs to be changed or fine-tuned relatively frequently, such as in the case of the optimized development of the alloy composition, the method is time-consuming and labor-consuming.

Therefore, a new powder mixing method is needed, which can quickly, accurately and stably adjust the components of the powder alloy material used for laser cladding and meet the requirement of cladding layer quality optimization.

Disclosure of Invention

The invention aims to provide a powder mixing device, laser cladding powder feeding equipment and laser cladding equipment so as to improve the laser cladding quality.

In a first aspect, the present invention provides a powder mixing device for mixing powders to be mixed, which are conveyed by a plurality of powder conveying pipes. The powder mixing device includes: a plurality of defeated powder structures, stirring structure, mixed structure and with stirring structure and mixed structure drive connection's driving piece. The upper surface of the mixing structure is provided with a plurality of protruding structures.

Each powder conveying structure is communicated with the corresponding powder conveying pipeline and is used for conveying the powder to be mixed conveyed by the powder conveying pipelines to the stirring structure.

The stirring structure is used for premixing the powder to be mixed under the driving of the driving piece, and the premixed powder is conveyed to the central area of the upper surface of the mixing structure through the powder leakage hole of the stirring structure.

The mixing structure is driven by the driving part to mix the premixed powder and then send the premixed powder out from the edge area of the upper surface of the mixing structure.

When the technical scheme is adopted, the powder mixing device provided by the invention comprises a plurality of powder conveying structures, a stirring structure, a mixing structure and a driving piece. Each powder conveying structure is communicated with the corresponding powder conveying pipeline and used for conveying the powder to be mixed conveyed by the powder conveying pipelines to the stirring structure. Can mix the powder to waiting of carrying in the stirring structure through setting up the stirring structure and premix, realize the preliminary mixing of the powder of waiting of carrying in the different pipelines for the powder of the downthehole output of leaking of stirring structure is the powder after premixing between the powder of multiple difference, the further mixed effect of strengthening the powder. On this basis, further mix the powder after will premixing through setting up mixed structure, at this moment, because mixed structure's upper surface is equipped with a plurality of protruding structures for carry into mixed structure upper surface premixed powder contact mixed structure's upper surface's protruding structure after, to the angle motion of difference, produce irregular collision, make this premixed powder's direction of motion disperse more, mix the effect better. And the powder leakage hole conveys the premixed powder to the central area of the upper surface of the mixing structure, so that the collision frequency of the premixed powder and the convex structure on the powder mixing structure is increased, and finally, after multiple collisions, the fully mixed powder is sent out from the edge area of the upper surface of the mixing structure. Meanwhile, the powder leakage hole conveys the premixed powder to the central area of the upper surface of the mixing structure, and the phenomenon that part of the premixed powder is directly sent out from the edge area of the upper surface of the mixing structure to influence the powder mixing effect of the powder mixing device can be prevented.

Meanwhile, the powder mixing device provided by the embodiment of the invention realizes different mass ratios of different powders in the final mixed powder by adjusting the flow rate of each powder to be mixed. Compared with the uniform pre-mixing powder of the traditional method, the powder mixing device provided by the invention is equivalent to divide all the powder to be mixed into countless small parts for mixing, each small part is uniformly mixed, and finally, the macroscopic element uniform distribution of the cladding layer is realized. Based on this, the powder mixing device provided by the embodiment of the invention can be used for mixing the powder to be mixed with large mass ratio difference.

In conclusion, the powder mixing device can realize uniform mixing of the powder with different mass ratios and realize accurate control of cladding material components, thereby improving the laser cladding effect and reducing the phenomena of cracking and the like.

In a second aspect, the present invention provides a laser cladding powder feeding apparatus, including the powder mixing device described in the first aspect or any one of the possible implementation manners of the first aspect, a plurality of powder conveying pipelines, a plurality of powder buckets, and a controller. Each powder conveying pipeline is connected with the powder conveying structure of the corresponding powder mixing device and the corresponding powder barrel.

The laser cladding powder feeding equipment further comprises a gas flow sensor and a gas pressure sensor which are arranged on the powder conveying structures or the powder conveying pipelines or the powder barrels, and the controller is in communication connection with the gas flow sensor and the gas pressure sensor respectively.

The beneficial effects of the laser cladding powder feeding apparatus provided by the second aspect are the same as those of the powder mixing device described in the first aspect or any possible implementation manner of the first aspect, and are not described herein again.

In a third aspect, the invention provides a laser cladding apparatus, comprising the laser cladding powder feeding apparatus described in the second aspect.

The beneficial effects of the laser cladding apparatus provided by the third aspect are the same as those of the powder mixing device described in the first aspect or any possible implementation manner of the first aspect, and are not described herein again.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic structural diagram of a laser cladding apparatus provided in an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a powder mixing device according to an embodiment of the present invention;

fig. 3 is a perspective view of a powder mixing device according to an embodiment of the present invention;

FIG. 4 is a top view of a powder mixing device according to an embodiment of the present invention;

FIG. 5 is a schematic view of a portion of a powder mixing apparatus according to an embodiment of the present invention;

in the figure: 1-a powder mixing device; 2-a powder conveying pipeline; 3-a powder barrel; 4-powder feeding pipeline; 5-laser cladding head; 11-powder conveying structure; 12-stirring structure; 13-a hybrid structure; 14-a drive member; 15-an upper shell; 16-a lower shell; 17-an extension bar; 18-plug; 19-a seal; 20-a throttle valve; 21-a filter element; 111-a powder inlet joint; 112-a powder inlet channel; 121-powder leakage hole; 122-a premixing chamber; 131-a raised structure; 132-powder mixing chamber; 133-powder outlet; 151-drive member cover; 161-a mixing chamber; 1611-funnel shaped configuration.

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.

It should be noted that the various schematic drawings of embodiments of the invention are illustrated in the accompanying drawings and are not drawn to scale. Wherein certain details are exaggerated and possibly omitted for clarity of understanding. The shapes of various regions, layers, and relative sizes and positional relationships therebetween shown in the drawings are merely exemplary, and deviations may occur in practice due to manufacturing tolerances or technical limitations, and a person skilled in the art may additionally design regions/layers having different shapes, sizes, relative positions, as actually required.

The words "exemplary" or "such as" are used herein to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" or "e.g.," is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, use of the word "exemplary" or "such as" is intended to present concepts related in a concrete fashion.

The laser cladding technology is a technological method for remarkably improving the wear resistance, corrosion resistance, heat resistance, oxidation resistance, electrical characteristics and the like of the surface of a base material by placing selected coating materials on the surface of a coated base body in different filling modes, simultaneously melting a thin layer on the surface of the base body through laser irradiation, and forming a surface coating which has extremely low dilution and is metallurgically combined with the base material after rapid solidification. The synchronous powder feeding method has the advantages of easy realization of automatic control, high laser energy absorption rate, no internal air holes, and particularly, the method can obviously improve the cracking resistance of a cladding layer when cladding metal ceramics, and ensure that hard ceramic phases can be uniformly distributed in the cladding layer. At present, metal powder materials used for laser cladding are generally obtained by a powder process of a traditional alloy ingot. The design of traditional alloy composition mainly aims at traditional metal processing technology such as casting, forging, build-up welding, and laser cladding's physical hot process has great difference with traditional metal processing technology, and the most obvious difference lies in its extremely fast heating and cooling rate to and the hot cold cycle process of relapseing many times, if do not optimize traditional alloy composition, crack defect appears more easily in the cladding in-process. For the requirement of optimizing the alloy composition, sometimes different alloy powder materials need to be mixed, or some single element metal powder is added into one alloy powder material, or some heterogeneous materials are added in order to meet some special performance requirements of a cladding layer, for example, WC ceramic particles are added into nickel-based alloy powder.

However, in the prior art, if laser cladding is performed by using mixed powder, a premixing method is generally used, that is, the powder is weighed and then mixed according to a certain proportion, a mixer rolls/shakes a powder container to mix the powder, and then the mixed powder is loaded into a powder feeding device of a laser cladding apparatus. The method is difficult to mix the powder uniformly, and particularly for the powder with large component proportion difference, the element distribution in the final cladding layer is not uniform; and the manual operation steps are more in the mixing process, the measurement precision is easily reduced, and impurities are introduced or powder oxidation pollution is caused. In addition, if the powder composition needs to be changed or fine-tuned relatively frequently, such as in the case of the optimized development of the alloy composition, the method is time-consuming and labor-consuming.

In order to solve the above technical problems, embodiments of the present invention provide a laser cladding apparatus, which is used for performing laser cladding on a surface of a substrate to obtain a cladding layer with good surface formation, no air holes or cracks, and relatively low cost.

Fig. 1 illustrates a schematic structural diagram of a laser cladding apparatus provided in an embodiment of the present invention. As shown in fig. 1, the laser cladding apparatus provided by the embodiment of the present invention includes a laser cladding powder feeding apparatus. According to the laser cladding equipment provided by the embodiment of the invention, the uniformly mixed powder is conveyed to the laser cladding head 5 through the powder conveying pipeline 4 by the laser cladding powder conveying equipment for laser cladding, so that a cladding layer with good surface forming and no air holes and cracks is obtained.

As shown in fig. 1, the laser cladding powder feeding apparatus includes: a powder mixing device 1, a plurality of powder conveying pipelines 2, a plurality of powder buckets 3 and a controller (not shown in the figure). Each powder conveying pipe 2 is connected with the powder conveying structure of the corresponding powder mixing device 1 and the powder barrel 3 of the corresponding powder feeder. The powder conveying structures or the powder conveying pipelines 2 or the powder buckets 3 are connected with a gas flow sensor (not shown in the figure) and a gas pressure sensor (not shown in the figure), and the controller is respectively in communication connection with the gas flow sensor and the gas pressure sensor. Through setting up gas flow sensor and gas pressure sensor for the defeated gaseous flow of powder and the defeated gaseous pressure of powder of defeated powder in defeated powder process all can independent control, thereby guarantee that the powder of treating mixing in every defeated powder pipeline 2 can be under defeated gaseous protection of powder and drive, carry and get into powder mixing arrangement 1, guarantee that the flow of the gaseous flow of carrying the powder accords with the laser cladding technological requirement. Meanwhile, each powder barrel 3 can adopt a rotating disc type powder feeding mode, so that the range of the powder feeding amount is wider, for example, the control of the powder feeding amount of 0.5g/min to 100g/min can be realized, and the mass ratio of the powder conveyed by each powder conveying pipeline 2 can be maximally 1: 200. based on this, the laser cladding powder feeding device provided by the embodiment of the invention can more fully mix the powder conveyed by different powder conveying pipelines 2 together by controlling the powder feeding amount of each powder conveying pipeline 2, so as to obtain the uniformly mixed powder, and therefore, by adopting the laser cladding powder feeding device provided by the embodiment of the invention, the powder with larger component ratio difference can be uniformly mixed.

In practical application, when the plurality of gas flow sensors and the plurality of gas pressure sensors are arranged on the plurality of powder barrels, the powder to be mixed in each powder barrel is conveyed into the powder conveying pipeline from the powder barrel under the driving of gas with pressure and certain flow velocity, at the moment, before the powder to be mixed is conveyed, the gas flow sensor in each powder barrel transmits the gas flow information in each powder barrel to the controller, the pressure sensor in each powder barrel transmits the gas pressure information in each powder barrel to the controller, the controller receives the gas flow information and the gas pressure information, and processes the gas flow information and the gas pressure information to judge whether the gas flow information and the gas pressure information accord with preset values, and under the condition that the gas flow information and the gas pressure information are determined to accord with preset values, controlling the gas with pressure to convey the powder to be mixed in each powder barrel into the powder conveying pipeline from the powder barrels. And under the condition that the gas flow information and the gas pressure information are determined not to accord with preset values, adjusting the gas flow and the gas pressure.

Fig. 2 illustrates a schematic structural diagram of a powder mixing device according to an embodiment of the present invention. As shown in fig. 2, the powder mixing device 1 is used for mixing powders to be mixed, which are conveyed by a plurality of powder conveying pipes 2. The powder mixing device includes: a plurality of powder conveying structures 11, a stirring structure 12, a mixing structure 13 and a driving part 14 which is in driving connection with the stirring structure 12 and the mixing structure 13.

As shown in fig. 2, each of the powder conveying structures 11 is communicated with the corresponding powder conveying pipe 2, and is used for conveying the powder to be mixed conveyed by the powder conveying pipe 2 to the stirring structure 12. It should be understood that the number of the powder conveying structures 11 is the same as that of the powder conveying pipelines 2, and the powder conveying structures are connected together in a one-to-one correspondence. The powder conveying pipe 2 is used for conveying fluid consisting of gas and powder to be mixed. The gas is usually inert gas commonly used for laser cladding, and the metal powder is protected from being oxidized when entering a cladding area for cladding. As for the number of the powder conveying structures 11, the setting can be carried out according to the actual situation. For example, the number of the powder conveying structures 11 can be set to 4, so as to realize 4-way powder conveying mixing; the number of the powder feeding devices can be set to be 6 so as to realize 6 paths of powder feeding and mixing; the number of the powder feeding devices may be 8, so as to realize 8-way powder feeding mixing and the like, which is not limited herein.

As shown in fig. 2, the stirring structure 12 is driven by the driving member 14 to pre-mix the powders to be mixed, and the pre-mixed powders are delivered to the central area of the upper surface of the mixing structure 13 through the powder leaking hole 121 of the stirring structure 12. It should be understood that the driving member 14 may be a driving motor, and may also be a driving member 14 such as an oil cylinder, etc. which can realize rotation.

As shown in fig. 2, the mixing structure 13 is driven by the driving member 14 to mix the premixed powders, and then the premixed powders are discharged from an edge area of an upper surface of the mixing structure 13. Wherein the upper surface of the mixing structure 13 is provided with a plurality of protruding structures 131. Specifically, the convex structure 131 is a hard sphere or a hard hemisphere. Wherein, the material of hard spheroid or the material of hard hemisphere is wear-resisting metal. The raised structure 131 may be secured to the upper surface of the hybrid structure 13 by welding or adhesive.

Therefore, the powder mixing device provided by the invention comprises a plurality of powder conveying structures, a stirring structure, a mixing structure and a driving part. Each powder conveying structure is communicated with the corresponding powder conveying pipeline and used for conveying the powder to be mixed conveyed by the powder conveying pipelines to the stirring structure. Can mix the powder to waiting of carrying in the stirring structure through setting up the stirring structure and premix, realize the preliminary mixing of the powder of waiting of carrying in the different pipelines for the powder of the downthehole output of leaking of stirring structure is the powder after premixing between the powder of multiple difference, the further mixed effect of strengthening the powder. On this basis, further mix the powder after will premixing through setting up mixed structure, at this moment, because mixed structure's upper surface is equipped with a plurality of protruding structures for carry into mixed structure upper surface premixed powder contact mixed structure's upper surface's protruding structure after, to the angle motion of difference, produce irregular collision, make this premixed powder's direction of motion disperse more, mix the effect better. And the powder leakage hole conveys the premixed powder to the central area of the upper surface of the mixing structure, so that the collision frequency of the premixed powder and the convex structure on the powder mixing structure is increased, and finally, after multiple collisions, the fully mixed powder is sent out from the edge area of the upper surface of the mixing structure. Meanwhile, the powder leakage hole conveys the premixed powder to the central area of the upper surface of the mixing structure, and the phenomenon that part of the premixed powder is directly sent out from the edge area of the upper surface of the mixing structure to influence the powder mixing effect of the powder mixing device can be prevented.

Meanwhile, the powder mixing device provided by the embodiment of the invention can divide the powder with different mass ratios to be mixed into a plurality of small parts for mixing by adjusting the flow rates of the powder with different mass ratios to be mixed, thereby realizing uniform mixing of the powder with different mass ratios. Based on this, the powder mixing device provided by the embodiment of the invention can be used for mixing the powder to be mixed with large mass ratio difference.

As shown in fig. 2, the powder mixing device 1 further includes an upper housing 15 and a lower housing 16, the upper housing 15 and the lower housing 16 are hermetically connected together, the driving member 14 is located in the upper housing 15, and an output shaft of the driving member 14 extends into the lower housing 16 and is in driving connection with the stirring structure 12 and the mixing structure 13 located in the lower housing 16, so that the stirring structure 12 and the mixing structure 13 can rotate under the driving of the driving member 14, thereby achieving the mixing of the powder.

As shown in fig. 2, in order to enhance the mixing effect of the powder, after the premixed powder is delivered from the powder leaking hole 121 to the central area of the upper surface of the mixing structure 13, a powder mixing cavity 132 is provided between the stirring structure 12 and the mixing structure 13, and the mixing cavity should have enough mixing space to allow the powder to move, collide and mix sufficiently, so that the powder mixing device 1 may further include an extension rod 17, one end of the extension rod 17 is connected with the output shaft of the driving member 14, and the other end is connected with the mixing structure 13 for transmitting the driving force of the driving member to the mixing structure. Under the action of the driving member 14, the extension rod 17 drives the mixing structure 13 to move together. Here, the size of the powder mixing chamber 132 and the length of the extension rod 17 are designed according to actual conditions, and are not limited herein.

As shown in fig. 2, the upper housing 15 may further include a driving member cover 151, and the upper housing 15 and the lower housing 16 are hermetically connected by the driving member cover 151. The driver 14 is sealingly connected to the driver cover 151. By providing the driving member cover 151 and fixing the driving member 14 on the driving member cover 151, the driving member 14 can be sealed as much as possible, and the situation that the driving member 14 is damaged due to the powder to be mixed entering the driving member 14 in the powder mixing process can be prevented.

In practice, as shown in fig. 2, the powder mixing device 1 may further include a plug 18, and the driving member 14 may be a motor. Specifically, after the driving member 14 is fixed to the driving member cover 151, the stopper 18 is used to seal the top of the driving member 14, and the driving member 14 is sealed inside the upper housing 15, so as to protect the driving member 14 and prevent particles such as dust from entering the driving member 14. The material of the plug 18 may be rubber, synthetic fiber, or the like, and is not limited herein.

As shown in fig. 2, the powder mixing device 1 further comprises a plurality of sealing elements 19 in order to achieve a sealed connection between the upper housing 15 and the lower housing 16 and a sealed connection between the driver 14 and the upper housing 15. At least one seal 19 is located at the connection of the drive member 14 and the upper housing 15 to prevent powder-laden gas from leaking out of the powder mixing device 1 through the mating surfaces of the drive member 14 and the upper housing 15. At least one seal 19 is located at the junction of the upper housing 15 and the lower housing 16 to prevent powder-laden gas from leaking out of the powder mixing device 1 through the mating surfaces of the upper housing 15 and the lower housing 16. When the upper housing 15 further includes a driver cap 151, the at least one seal 19 is located at the connection of the driver 14 and the driver cap 151 to prevent powder-laden gas from entering the mounting cavity of the driver 14 and affecting the performance of the driver 14.

Fig. 3 illustrates a perspective view of a powder mixing device according to an embodiment of the present invention, and fig. 4 illustrates a plan view of the powder mixing device according to the embodiment of the present invention. As shown in fig. 2 to 4, the powder mixing device 1 further includes a throttle valve 20 and a filter member 21. The throttle valve 20 is communicated with the lower casing 16 and is used for adjusting the gas flow in the lower casing 16 and discharging the gas with excessive flow out of the powder mixing device 1, so that the flow of the gas finally entering the laser cladding head 5 through the powder outlet of the powder mixing device 1 meets the requirements of the laser cladding process. It should be understood that the number of the throttle valves 20 may be one or more, and is not limited herein.

In order to further ensure that the flow of the gas entering the laser cladding head 5 from the powder outlet of the powder mixing device 1 meets the requirements of the laser cladding process, the powder mixing device 1 may further include a gas flow sensor (not shown in the figure). The gas flow sensor can be connected with the gas outlet of the throttle valve 20, and the flow of the gas entering the laser cladding head 5 from the powder outlet of the powder mixing device 1 is determined by judging the sum of the gas flows delivered to the powder mixing device 1 by each powder delivery pipeline 2 and the difference of the gas flows flowing out from the gas outlet of the throttle valve 20. Of course, the gas flow sensor may also be connected to the powder outlet of the powder mixing device 1, and the gas flow at the powder outlet of the powder mixing device 1 is detected to ensure that the flow of the gas entering the laser cladding head 5 from the powder outlet of the powder mixing device 1 meets the requirements of the laser cladding process. Here, the gas flow sensor is a commercially available device, and the range of options is wide, and is not limited herein.

In practical applications, the powder mixing apparatus 1 may further include a controller, which is in communication with the gas flow sensor and the throttle valve, and is used for controlling the gas flow sensor to detect the gas flow and controlling the on/off of the throttle valve. The intelligent control can be realized by arranging the controller, and the labor cost is reduced.

As shown in fig. 2-4, the filter element 21 is at least partially located at the junction of the throttle 20 and the lower housing 16. The filter element 21 may be a filter screen or a filter element, and the mesh number of the filter screen or the filter element is 1000 to 2500 meshes, for example, the mesh number of the filter screen or the filter element is 1000 meshes, the mesh number of the filter screen or the filter element is 1250 meshes, and the mesh number of the filter screen or the filter element is 1500 meshes. The mixed powder in the powder mixing device 1 can be isolated from the throttle 20 by the filter element 21, which blocks the powder from exiting the powder mixing device 1 with the blow-off gas.

As shown in fig. 2 to 4, the lower housing 16 may further include a mixing chamber 161, the bottom of the mixing chamber 161 is a funnel-shaped structure 1611, the powder mixed in the powder mixing chamber 132 of the mixing structure 13 is discharged from an edge region of the upper surface of the mixing structure 13, enters the funnel-shaped structure 1611, then flows out of the funnel-shaped structure 1611, is collected at a powder outlet of the powder mixing apparatus 1, and is then fed into the laser cladding head 5, so as to improve the powder collection efficiency, and the powder may be further mixed after being collected at the powder outlet.

In practical applications, as shown in fig. 2 to 4, the mixing structure 13 may be a diamond shape, and a gap is formed between the funnel-shaped structure 1611 and the side wall of the mixing structure 13, through which the powder mixed by the mixing structure 13 flows out under the driving of its own gravity and air pressure. At the moment, the gap has a steady flow effect on the fluid formed by the gas and the powder which are mixed together, so that the fluid entering the laser cladding head 5 through the powder outlet of the powder mixing device 1 is more stable, the uniformity of the laser cladding powder is ensured, and the laser cladding effect is improved.

Fig. 5 is a schematic diagram illustrating a partial structure of a powder mixing device according to an embodiment of the present invention. As shown in fig. 2 to 5, each powder conveying structure 11 includes a powder inlet joint 111 and a powder inlet passage 112 communicating with the powder inlet joint 111. The powder inlet joint 111 is connected with the corresponding powder conveying pipelines 2 in a matching manner, and the powder inlet channel 112 is used for conveying powder to be mixed conveyed by the powder conveying pipelines 2 into the stirring structure 12 so as to improve the powder conveying efficiency.

In practical applications, as shown in fig. 2 to 5, each of the powder inlet channels 112 is located in an area where the stirring structure 12 is located, so that the powder conveyed by the powder inlet channels 112 can be accurately fed into the stirring structure 12, and after being premixed in the stirring structure 12, the premixed powder flows out from the powder leakage hole 121 of the stirring structure 12. Specifically, the number of the powder conveying structures 11 can be selected according to the number of kinds of powder to be mixed, and is not limited herein.

As shown in fig. 2-5, the stirring structure 12 may have a premixing chamber 122, and the premixing chamber 122 may be shaped like a funnel. The leakage holes 121 are located at the bottom of the premixing chamber 122. By arranging the powder leakage hole 121 at the bottom of the premixing cavity 122, the powder to be mixed can be rotated and mixed from the top of the premixing cavity 122, and then gradually moves towards the powder leakage hole 121 at the bottom of the premixing cavity 122 and flows out from the powder leakage hole 121 under the driving of the self gravity and the pressure of the gas, so that the powder to be mixed can be more fully premixed. The number of the powder leakage holes 121 may be selected according to actual conditions, and is not limited herein. And in order to ensure that the stirring structure 12 can rotate under the action of the driving member 14, a gap is formed between the stirring structure 12 and the mixing cavity 161 of the lower shell 16, and the gap is as small as possible in order to prevent the powder to be mixed from flowing out of the gap. Specifically, the width of the gap may be selected according to actual conditions, and is not limited herein.

As shown in fig. 2 to 5, the upper surface of the mixing structure 13 is a paraboloid or a cone. The vertex of the paraboloid or the vertex of the conical surface is arranged close to the stirring structure, so that the dispersion area and the dispersion direction among the powder particles are increased, the uncertainty factor among powder collision is increased, and the mixing effect of the powder is better.

As shown in fig. 2 to 5, the edge area of the upper surface of the mixing structure 13 has a plurality of powder discharge holes 133, and the mixed powder flows out from the plurality of powder discharge holes 133. Through setting up this a plurality of powder outlet 133 for the powder of mixing at the upper surface of mixed structure 13 when powder, only partial powder can flow out from powder outlet 133 at every turn, and partial powder continues to move under mixed structure 13's drive, thereby promotes the mixture homogeneity of powder.

While the invention has been described in connection with various embodiments, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a review of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

While the invention has been described in conjunction with specific features and embodiments thereof, it will be evident that various modifications and combinations can be made thereto without departing from the spirit and scope of the invention. Accordingly, the specification and figures are merely exemplary of the invention as defined in the appended claims and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of the invention. It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A powder mixing device is used for mixing powder to be mixed and conveyed by a plurality of powder conveying pipelines; it is characterized by comprising: the powder conveying device comprises a plurality of powder conveying structures, a stirring structure, a mixing structure and a driving piece in driving connection with the stirring structure and the mixing structure; the upper surface of the mixing structure is provided with a plurality of protruding structures;

each powder conveying structure is communicated with the corresponding powder conveying pipeline and is used for conveying the powder to be mixed conveyed by the powder conveying pipelines to the stirring structure;

the stirring structure is used for premixing the powder to be mixed under the driving of the driving piece, and conveying the premixed powder to the central area of the upper surface of the mixing structure through the powder leakage hole of the stirring structure;

2. The powder mixing device of claim 1, further comprising an upper housing and a lower housing, the upper housing and the lower housing being sealingly coupled together, the drive member being located within the upper housing, the output shaft of the drive member extending into the lower housing and being drivingly coupled to the mixing structure and the agitation structure located within the lower housing.

3. The powder mixing device of claim 2, further comprising a plurality of seals; at least one sealing element is positioned at the joint of the driving element and the upper shell, and at least one sealing element is positioned at the joint of the upper shell and the lower shell.

4. The powder mixing device of claim 2, further comprising a throttle valve and a filter element; the throttle valve is communicated with the lower shell and used for adjusting the air pressure in the lower shell, and the filter element is at least partially positioned at the joint of the throttle valve and the lower shell; wherein the content of the first and second substances,

the filter element is a filter screen or a filter element, and the mesh number of the filter screen or the mesh number of the filter element is 1000-2500 meshes; and/or the presence of a gas in the gas,

the lower shell is provided with a mixing cavity, the bottom of the mixing cavity is of a funnel-shaped structure, and powder mixed by the mixing structure is sent out from the edge area of the upper surface of the mixing structure and enters the funnel-shaped structure.

5. The powder mixing device according to claim 4, further comprising a gas flow sensor connected to a gas outlet of the throttle valve; and/or the gas flow sensor is connected with a powder outlet of the powder mixing device.

6. The powder mixing device according to any one of claims 1 to 5, wherein each powder conveying structure comprises a powder inlet joint and a powder inlet channel communicated with the powder inlet joint, the powder inlet joint is connected with the corresponding powder conveying pipeline in a matching manner, and the powder inlet channel is used for conveying the powder to be mixed conveyed by the powder conveying pipelines to the stirring structure; and/or the presence of a gas in the gas,

the stirring structure is provided with a premixing cavity, and the shape of the premixing cavity is similar to a funnel shape; the powder leakage hole is positioned at the bottom of the premixing cavity.

7. The powder mixing device of any one of claims 1 to 5, wherein the upper surface of the mixing structure is a paraboloid or a cone, and the vertex of the paraboloid or the vertex of the cone is disposed adjacent to the stirring structure; and/or the presence of a gas in the gas,

the edge area of the upper surface of the mixing structure is provided with a plurality of powder outlet holes, and the mixed powder flows out from the powder outlet holes.

8. The powder mixing device according to any one of claims 1 to 5, wherein the convex structure is a hard sphere or a hard hemisphere; the hard sphere or the hard hemisphere is made of metal; and/or the presence of a gas in the gas,

the powder mixing device further comprises an extension rod, one end of the extension rod is connected with the output shaft of the driving piece, and the other end of the extension rod is connected with the mixing structure and used for transmitting the driving force of the driving piece to the mixing structure.

9. A laser cladding powder feeding device is characterized by comprising the powder mixing device as claimed in any one of claims 1 to 8, a plurality of powder conveying pipelines, a plurality of powder barrels and a controller; each powder conveying pipeline is connected with the powder conveying structure of the corresponding powder mixing device and the corresponding powder barrel;

the laser cladding powder feeding equipment further comprises a gas flow sensor and a gas pressure sensor which are arranged on the plurality of powder conveying structures, the plurality of powder conveying pipelines or the plurality of powder barrels, and the controller is in communication connection with the gas flow sensor and the gas pressure sensor respectively.

10. A laser cladding apparatus comprising the laser cladding powder feeding apparatus of claim 9.