阅读说明：本技术 一种模腔定量加粉设备 (Die cavity quantitative powder adding equipment ) 是由 张�杰 刘兵 卢振明 周湘文 唐亚平 唐春和 于 2020-04-29 设计创作，主要内容包括：本发明公开了一种模腔定量加粉设备,包括预压模具、机架；料仓安装于所述机架上,所述料仓的进料口与粉料输送管道相连通；加粉组件包括导料管组件和筛网组件,所述料仓的出料口通过所述导料管组件与所述预压模具的进料口相连通,以便所述料仓中的粉料经所述导料管组件传输至所述预压模具的模腔内；所述筛网组件可旋转地设置于所述导料管组件的管道内；振动机构的敲击件安装于所述敲击所述预压模具外,并敲击所述预压模具。筛网组件的转动能够保证给料尽量均匀,实现定量给料,且给料均匀松散；加料过程中,在加粉的同时敲击振动机构以一定的频率对模具进行振动敲击,使粉体均匀填充模腔各处,至粉体充满整个模具的模腔,提高了加粉均匀性。(The invention discloses a die cavity quantitative powder adding device, which comprises a prepressing die and a frame; the storage bin is arranged on the rack, and a feed inlet of the storage bin is communicated with the powder conveying pipeline; the powder adding assembly comprises a material guide pipe assembly and a screen assembly, and a discharge hole of the storage bin is communicated with a feed hole of the pre-pressing die through the material guide pipe assembly so that powder in the storage bin can be conveniently transmitted into a die cavity of the pre-pressing die through the material guide pipe assembly; the screen assembly is rotatably arranged in the pipeline of the material guide pipe assembly; and a knocking piece of the vibration mechanism is arranged outside the prepressing die and is used for knocking the prepressing die. The rotation of the screen assembly can ensure that the feeding is as uniform as possible, quantitative feeding is realized, and the feeding is uniform and loose; in the feeding process, the vibration mechanism is knocked to vibrate the die at a certain frequency while powder is added, so that the powder is uniformly filled in all parts of the die cavity, the die cavity of the whole die is filled with the powder, and the powder adding uniformity is improved.)

1. The utility model provides a die cavity ration powder adding equipment, includes pre-compaction mould (12), its characterized in that, die cavity ration powder adding equipment still includes:

a frame;

the storage bin (1) is mounted on the rack, and a feed inlet of the storage bin (1) is communicated with a powder conveying pipeline;

the powder adding assembly comprises a material guide pipe assembly and a screen assembly, and a discharge hole of the stock bin (1) is communicated with a feed hole of the pre-pressing die (12) through the material guide pipe assembly so that powder in the stock bin (1) can be conveyed into a die cavity of the pre-pressing die (12) through the material guide pipe assembly; the screen assembly is rotatably arranged in the pipeline of the material guide pipe assembly;

and the knocking piece of the vibration mechanism (10) is arranged outside the prepressing die (12) and is used for knocking the prepressing die (12).

2. The apparatus of claim 1, wherein the guide tube assembly comprises:

the feeding hole of the first material guiding pipe (2) is communicated with the discharging hole of the storage bin (1);

a discharge hole of the second material guiding pipe (8) is communicated with the die cavity;

and one end of the communicating pipe (4) is communicated with the discharge hole of the first material guide pipe (2), and the other end of the communicating pipe (4) is communicated with the feed hole of the second material guide pipe (8).

3. The apparatus of claim 2, wherein the screen assembly comprises:

a first screen assembly (3), wherein the first screen assembly (3) is rotatably arranged between the first material guide pipe (2) and the communicating pipe (4);

a second screen assembly (5), wherein the second screen assembly (5) is rotatably installed between the second guide pipe (8) and the communicating pipe (4).

4. A moulding chamber dosing apparatus according to claim 3, wherein the first screen assembly (3) comprises:

the first screen is rotatably arranged at the joint of the first material guide pipe (2) and the communicating pipe (4);

a first screen frame, an outer edge of the first screen being fixedly mounted to the first screen frame,

the gear shaft of the first screen gear is fixed on the rack, and the first screen frame is fixedly arranged at the center of the first screen gear;

the first screen motor (6), the first screen motor (6) with first screen gear transmission is connected, and drive first screen gear horizontal rotation.

5. A moulding chamber dosing apparatus according to claim 3, wherein the second screen assembly (5) comprises:

the second screen is rotatably arranged at the joint of the communicating pipe (4) and the second material guide pipe (8);

a second screen frame to which an outer edge of the second screen is mounted;

the gear shaft of the second screen gear is fixed on the rack, and the second screen frame is fixedly arranged at the central position of the second screen gear;

and the second screen motor (7) is in transmission connection with the second screen gear and drives the second screen gear to rotate horizontally.

6. The apparatus of any of claims 1-5, wherein the powdering assemblies are in a plurality of groups, each of the powdering assemblies being mounted along a production line to form a plurality of stations.

7. The quantitative powder adding device for the mold cavity according to any one of claims 1 to 5, further comprising a material probe (9), wherein a probe head of the material probe (9) extends into the mold cavity and obtains the level of powder in the mold cavity.

8. The die cavity quantitative powder adding device according to any one of claims 1-5, characterized in that an arch-breaking spiral stirring structure is further arranged inside the bin (1).

9. A dosing device for a moulding cavity according to any one of claims 1 to 5, characterised in that the vibrating means (10) comprise:

a rapping hammer forming said rapper;

the knocking hammer comprises a knocking motor, wherein a cam is arranged on an output shaft of the knocking motor, and a rod end of the knocking hammer is arranged on the outer contour of the cam;

the knocking position of the knocking hammer on the pre-pressing die (12) is the upper end face of the pre-pressing die (12), and the distance between the knocking hammer and the center of the upper end face of the pre-pressing die (12) is 46.5-51.5 mm.

10. The die cavity quantitative powder adding equipment as claimed in any one of claims 1 to 5, wherein a mechanical claw (11) is further arranged on the machine frame, the shape of the mechanical claw (11) is matched with the shape of a lower die of a pre-pressing die (12), and the mechanical claw (11) horizontally reciprocates between a powder adding station and a nest forming station.

Technical Field

The invention relates to the technical field of nuclear technology devices, in particular to a device for quantitatively adding powder to a die cavity of a die in a spherical fuel element/matrix graphite nodule forming process.

Background

The spherical fuel elements are widely applied to various reactor types, such as a pebble-bed high-temperature gas-cooled reactor, a molten salt reactor and the like, wherein the fuel adopted by the pebble-bed high-temperature gas-cooled reactor is the spherical fuel elements with the diameter of about 60mm, the area containing the fuel in the center of a sphere is called a fuel area, and the area at the periphery of the fuel area is called a fuel-free area. The thickness of the fuel-free zone is required to be controlled to be 4-6 mm. The fuel area and the fuel-free area are basically concentrically distributed, and if the fuel area is seriously eccentric and the thickness of the fuel-free area is too small, the element is unqualified.

Adding a certain amount of matrix graphite powder into a lower half die of the die, then placing a core ball, placing an upper half die, then adding the matrix graphite powder quantitatively until the powder is filled in the whole die cavity, and forming a fuel area and a fuel-free area of the fuel element through pressing, heat treatment and turning. The eccentricity of the fuel area is mainly controlled by various factors such as the powder adding amount of the lower half die in the fuel-free area, the uniformity during powder adding, the height of a powder adding nest, the dimensional stability of a preformed fuel area (core ball), the control precision of powder adding of an upper die and the like, certain feeding errors exist in the powder adding and particle adding process and the lower die powder adding process, in order to ensure the dimensional stability of a final product and improve the yield, the accumulated errors caused by the powder adding and particle adding process and the lower die powder adding process need to be supplemented by the final powder adding of a pre-pressing die, and the process requirements can be met when the powder adding error is controlled within 3%. Therefore, the relatively accurate control of the powder adding amount of the lower die and the die cavity has a remarkable effect on improving the eccentricity of the fuel area.

Disclosure of Invention

In view of this, the present invention provides a quantitative powder adding apparatus for a mold cavity, so as to improve the production efficiency of powder adding operation, realize the precise control of powder adding amount of the mold cavity, and improve the powder adding uniformity.

In order to solve the technical problems, the invention adopts the following technical scheme:

the utility model provides a die cavity ration powder equipment, includes the pre-compaction mould, die cavity ration powder equipment still includes:

a frame;

the storage bin is arranged on the rack, and a feed inlet of the storage bin is communicated with the powder conveying pipeline;

the powder feeding assembly comprises a material guide pipe assembly and a screen assembly, and a discharge port of the storage bin is communicated with a feed port of the pre-pressing die through the material guide pipe assembly so that powder in the storage bin can be conveniently transmitted into a die cavity of the pre-pressing die through the material guide pipe assembly; the screen assembly is rotatably arranged in the pipeline of the material guide pipe assembly;

and the knocking piece of the vibration mechanism is arranged outside the prepressing die in a knocking way and is used for knocking the prepressing die.

Further, the guide tube assembly comprises:

the feed inlet of the first material guide pipe is communicated with the discharge outlet of the storage bin;

the discharge hole of the second material guiding pipe is communicated with the die cavity;

and one end of the communicating pipe is communicated with the discharge hole of the first material guide pipe, and the other end of the communicating pipe is communicated with the feed hole of the second material guide pipe.

Further, the screen assembly includes:

a first screen assembly rotatably installed between the first guide duct and the communicating pipe;

and the second screen assembly is rotatably arranged between the second guide pipe and the communicating pipe.

Further, the first screen assembly includes:

the first screen is rotatably arranged at the joint of the first material guide pipe and the communicating pipe;

a first screen frame, an outer edge of the first screen being fixedly mounted to the first screen frame,

the gear shaft of the first screen gear is fixed on the rack, and the first screen frame is fixedly arranged at the center of the first screen gear;

and the first screen motor is in transmission connection with the first screen gear and drives the first screen gear to rotate horizontally.

Further, the second screen assembly includes:

the second screen is rotatably arranged at the joint of the communicating pipe and the second material guide pipe;

a second screen frame to which an outer edge of the second screen is mounted;

the gear shaft of the second screen gear is fixed on the rack, and the second screen frame is fixedly arranged at the central position of the second screen gear;

and the second screen motor is in transmission connection with the second screen gear and drives the second screen gear to rotate horizontally.

Further, the powder adding assemblies are in multiple groups, and each powder adding assembly is installed along the production line to form multiple stations.

Furthermore, the material detection device also comprises a material probe, wherein a detection head of the material probe extends into the die cavity and acquires the material level of powder in the die cavity.

Further, the inside of feed bin still sets up broken arch spiral stirring structure.

Further, the vibration mechanism includes:

a rapping hammer forming said rapper;

the knocking hammer comprises a knocking motor, wherein a cam is arranged on an output shaft of the knocking motor, and a rod end of the knocking hammer is arranged on the outer contour of the cam;

the knocking position of the knocking hammer on the pre-pressing die is the upper end face of the pre-pressing die, and the distance between the knocking hammer and the center of the upper end face of the pre-pressing die is 46.5-51.5 mm.

Furthermore, the machine frame is also provided with a mechanical claw, the shape of the mechanical claw is matched with the shape of a lower die of the pre-pressing die, and the mechanical claw horizontally reciprocates between the powder adding station and the nest making station.

The invention has the following beneficial effects:

according to the invention, by adopting the technical scheme, the rotatable screen assembly is arranged in the powder feeding assembly, so that in the blanking process, the rotation of the screen assembly can ensure that the feeding is as uniform as possible, the quantitative feeding is realized, and the feeding is uniform and loose; in the charging process, the vibration mechanism is knocked to perform vibration knocking on the mold at a certain frequency while adding powder, so that the powder is uniformly filled in all parts of the mold cavity until the powder is filled in the mold cavity of the whole mold, and the vibration knocking function is to improve the flowability of the powder so that the powder is uniformly distributed around the fuel area and is filled in the whole mold cavity of the mold; meanwhile, the die rotating mechanism mainly enables the pre-pressing die to rotate at a certain speed during powder adding, improves the flowability of powder and enables the powder to uniformly flow to all parts of the die cavity, and is matched with the knocking vibration mechanism for use, so that the distribution uniformity of the powder in the die cavity is remarkably improved, and the uniform distribution of the powder is ensured. And the powder adding assembly can be arranged at multiple stations, so that powder adding of a plurality of forming lower dies can be completed at multiple stations, and the production efficiency is obviously improved.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical means of the present invention more clearly understood and to make the technical means implementable in accordance with the contents of the description, and to make the above and other objects, technical features, and advantages of the present invention more comprehensible, one or more preferred embodiments are described below in detail with reference to the accompanying drawings.

Drawings

One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the figures in which like reference numerals refer to similar elements and which are not to scale unless otherwise specified.

FIG. 1 is a schematic structural diagram of one embodiment of a quantitative powder adding apparatus for a mold cavity according to the present invention;

fig. 2 is a view of the mold cavity dosing apparatus of fig. 1 in another orientation.

Description of reference numerals:

1. feed bin 2, first stock guide 3, first screen assembly 4, communicating pipe

5. A second screen assembly 6, a first screen motor 7 and a second screen motor

8. A second material guide pipe 9, a material probe 10, a vibration mechanism 11 and a mechanical claw

12. Pre-pressing die 13, rotating motor 14, rack 15 and fixing plate

16 double-helix hybrid motor

Detailed Description

The following detailed description of the present invention is provided in conjunction with the accompanying drawings, but it should be understood that the scope of the present invention is not limited to the specific embodiments.

Throughout the specification and claims, unless explicitly stated otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element or component but not the exclusion of any other element or component.

Spatially relative terms, such as "below," "lower," "upper," "above," "upper," and the like, may be used herein for ease of description to describe one element or feature's relationship to another element or feature in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the object in use or operation in addition to the orientation depicted in the figures. For example, if the items in the figures are turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the elements or features. Thus, the exemplary term "below" can encompass both an orientation of below and above. The article may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative terms used herein should be interpreted accordingly.

In one embodiment, as shown in fig. 1 and 2, the present invention provides a quantitative powder adding device for a mold cavity, which comprises a prepressing mold 12, a frame, a silo 1, a powder adding component and a vibrating mechanism 10.

Wherein, feed bin 1 install in the frame, the feed inlet and the powder pipeline of feed bin 1 are linked together, and feed bin 1 is used for the buffer memory to pass through the material that pipeline carried and come to with the powder dispersion in feed bin 1 in order to prevent that the powder from taking a bridge in feed bin 1. And, the inside of feed bin 1 still sets up broken spiral stirring structure that encircles, adopts double helix hybrid motor to drive broken spiral stirring structure that encircles, can pave the base member powder in the feed bin 1 and distribute and play broken effect of encircleing, and feed bin 1, double helix hybrid motor 16 etc. all fix in the frame through the mode of hard joint.

The powder feeding assembly comprises a material guide pipe assembly and a screen assembly, and a discharge hole of the storage bin 1 is communicated with a feed hole of the pre-pressing die 12 through the material guide pipe assembly, so that powder in the storage bin 1 is conveyed into a die cavity of the pre-pressing die 12 through the material guide pipe assembly; the screen assembly is rotatably disposed in the duct of the guide duct assembly. The knocking part of the vibration mechanism 10 is installed outside the knocking of the pre-pressing mold 12, and the knocking of the pre-pressing mold 12.

The material guide pipe assembly is used for conveying materials, and comprises a first material guide pipe 2, a second material guide pipe 8 and a communicating pipe 4 in order to ensure the material conveying efficiency; the feeding hole of the first material guiding pipe 2 is communicated with the discharging hole of the storage bin 1, the discharging hole of the second material guiding pipe 8 is communicated with the die cavity, one end of the communicating pipe 4 is communicated with the discharging hole of the first material guiding pipe 2, and the other end of the communicating pipe is communicated with the feeding hole of the second material guiding pipe 8.

Wherein, the first baffle pipe 2 among the baffle pipe assembly sets up in upper portion, for last baffle pipe, and second baffle pipe 8 sets up in the lower part, for lower baffle pipe, and communicating pipe 4 is straight material pipe, sets up between last baffle pipe and lower baffle pipe, the top of going up the baffle pipe is connected with the discharge gate zonulae occludens of the bottom of feed bin 1, goes up and is equipped with first screen assembly 3 between baffle pipe and the straight material pipe, be equipped with second screen assembly 5 between straight material pipe and the lower baffle pipe. The upper material guide pipe, the straight material guide pipe and the lower material guide pipe are fixed on a transverse plate of the rack through bases of the pipe clamps. Specifically, the diameters of the upper material guide pipe, the straight material guide pipe and the lower material guide pipe are all 10-20 mm, and the distance between the center position of each pipe and the center of the pipe orifice is 5-10 mm, preferably 6-8 mm; the upper material guide pipe and the straight material guide pipe, and the straight material guide pipe and the lower material guide pipe are connected in a tight fit mode, and are sealed by an inner sealing piece and an outer sealing piece.

In this embodiment, the screen assemblies are provided in two sets, the apparatus further comprises a material probe 9, and a probe head of the material probe 9 extends into the mold cavity and obtains the powder material level in the mold cavity. In the feeding process, the powder material is quantified and conveyed through the rotation of the screen and the combination of the material probe 9.

Specifically, the screen assemblies include a first screen assembly 3 and a second screen assembly 5, the two screen assemblies are arranged at intervals in the vertical direction, the first screen assembly 3 is rotatably installed between the first material guiding pipe 2 and the communicating pipe 4, and the second screen assembly 5 is rotatably installed between the second material guiding pipe 8 and the communicating pipe 4.

In actual equipment, the rotation of the screen in each screen assembly is realized by driving a motor, each powder adding assembly can comprise two screens, the rotation of each screen is independently controlled by the motor, and the rotation of each screen is realized by gear transmission.

That is, the first screen assembly 3 includes a first screen, a first screen frame, a first screen gear, and a first screen motor 6; the first screen mesh is rotatably mounted at the joint of the first material guide pipe 2 and the communicating pipe 4, the outer edge of the first screen mesh is fixedly mounted on the first screen mesh frame, a gear shaft of the first screen mesh gear is fixed on the frame, the first screen mesh frame is fixedly arranged at the center of the first screen mesh gear, and the first screen mesh motor 6 is in transmission connection with the first screen mesh gear and drives the first screen mesh gear to rotate horizontally. Wherein, the aperture position of the first screen is 5-12 meshes, preferably 6-10 meshes.

The second screen assembly 5 comprises a second screen, a second screen frame, a second screen gear and a second screen motor 7; the second screen is rotatably mounted at the joint of the communicating pipe 4 and the second material guiding pipe 8, the outer edge of the second screen is mounted on the second screen frame, the gear shaft of the second screen gear is fixed on the rack, the second screen frame is fixedly mounted at the center of the second screen gear, and the second screen motor 7 is in transmission connection with the second screen gear and drives the second screen gear to rotate horizontally. Wherein the aperture of the second screen mesh is 8-16 meshes, preferably 10-14 meshes.

In the working process, the stock bin 1 is used for storing a certain amount of matrix graphite powder, and the matrix graphite powder in the stock bin 1 is continuously and uniformly dispersed and falls into the first material guide pipe 2 through the discharge hole by the arch-breaking spiral stirring structure arranged in the stock bin 1. Then the matrix graphite powder in the first material guiding pipe 2 falls into the communicating pipe 4 with the same looseness through the rotation of the first screen. In the communicating pipe 4, the matrix graphite powder in the communicating pipe 4 falls into the second material guiding pipe 8 with the same looseness degree through the rotary sieving of the second screen, and a certain looseness degree is formed to fall into a die cavity of the fuel-free area pre-pressing die 12. When the weighing machine is used for weighing, the corresponding screen mesh gear is driven by the screen mesh motor so as to drive the corresponding screen mesh to rotate, so that the conveying of matrix graphite powder is realized, and the rotating speed of the corresponding screen mesh is changed by adjusting the rotating speed of the screen mesh motor or the running time of the screen mesh motor is changed, so that the purpose of controlling the quantitative feeding is achieved.

In order to improve the production efficiency, a plurality of stations are synchronously powered, the plurality of sets of the powder feeding assemblies are arranged, and each powder feeding assembly is arranged along the production line to form a plurality of stations.

The vibration mechanism 10 comprises a knocking hammer and a knocking motor, wherein the knocking hammer forms the knocking part, a cam is arranged on an output shaft of the knocking motor, and a rod end of the knocking hammer is arranged on the outer contour of the cam; the knocking position of the knocking hammer on the pre-pressing die 12 is the upper end face of the pre-pressing die 12, and the distance from the knocking hammer to the center of the upper end face of the pre-pressing die 12 is 46.5-51.5 mm. The powder fluidity is improved through the vibration knocking of the vibration hammer, so that the powder is uniformly distributed around the fuel area and is filled in the whole die cavity of the die.

Furthermore, a mechanical claw 11 is further arranged on the rack, the mechanical claw 11 is mounted on the rack through a fixing plate 15, the shape of the mechanical claw 11 is matched with the shape of a lower die of the pre-pressing die 12, and the mechanical claw 11 horizontally reciprocates between a powder adding station and a nest making station; the pre-pressing mould 12 is positioned by the gripper 11 to the powder feeding station and the pre-pressing mould 12 filled with powder is removed from the powder feeding station and transported to a conveyor belt.

The prepressing die 12 is also provided with a die rotating mechanism, and the prepressing die 12 is used for preforming the powder and forming a prepressing body with a certain shape during prepressing; the mold rotating mechanism is mainly used for rotating the pre-pressing mold 12 at a certain speed during powder adding, so that the flowability of the powder is improved, the powder uniformly flows to all parts of the mold cavity, and the mold rotating mechanism is driven by a rotating motor 13.

The working principle and the working process of the die cavity quantitative powder adding device provided by the invention are briefly described based on the specific implementation mode as follows:

the working principle of the die cavity quantitative powder adding equipment provided by the invention is as follows:

a double-helix stirrer is arranged in a graphite matrix powder bin 1, the lower part of the bin 1 is connected with a first material guide pipe 2, a first screen assembly 3 is arranged between the first material guide pipe 2 and a communicating pipe 4, and matrix powder in the first material guide pipe 2 falls into the communicating pipe 4 with the same looseness degree through the rotary screening of the first screen assembly 3;

the second screen assembly 5 is arranged between the communicating pipe 4 and the second material guiding pipe 8, matrix powder in the communicating pipe 4 is formed into certain looseness through rotary sieving of the second screen, the matrix graphite powder is conveyed to a preforming die through the second material guiding pipe 8, and the powder adding process is accompanied with knocking vibration and rotation of the preforming die. The top of the core ball is provided with a material sensor, and when graphite matrix powder is added to a set position of the material sensor, the periphery of the core ball in the preforming mold is filled with the matrix powder graphite. The adding amount and the powder adding precision of the graphite matrix powder are adjusted by changing the position and the sensitivity of the material sensor; the uniformity, the powder adding error and the powder adding time of the powder adding are adjusted by adjusting the rotating speed of the screen.

Matrix powder graphite is added into a die cavity of a spherical fuel element fuel-free area preforming die through a rotary screen blanking assembly, after the die cavity of the whole preforming die is filled with the matrix powder graphite, the screen assembly stops rotating, a die rotating mechanism stops rotating and descends, a knocking vibration device ascends, then a mechanical arm grabbing mechanism clamps the die filled with powder and moves the die backwards to a conveying line, and meanwhile the die not filled with powder is conveyed to a powder filling station from a preparation position and enters the next working cycle.

The rotary screen assembly is tightly connected with the discharging pipe, a sealing ring is arranged at the joint, a die charging cover is arranged at the lower end of the charging pipe, the die cover is close to and sleeved on the upper die during charging, and an exhaust pipe is arranged between the die cover and the upper surface of the die, so that the dust is effectively prevented from overflowing.

The working process of the die cavity quantitative powder adding equipment provided by the invention is as follows:

(1) feeding matrix powder graphite into a bin 1;

(2) conveying the preforming mold to a powder adding station from the preparation station by a mechanical handle;

(3) the mould rotating mechanism is lifted to the feeding position;

(4) the knocking vibration device descends to the right position and starts to vibrate and knock;

(5) starting a spiral distributor in the matrix powder bin 1, and distributing the graphite matrix powder to six upper material guide pipes;

(6) starting a motor of the upper screen rotating assembly, enabling the upper screen assembly to rotate, and enabling the matrix powder to be screened by the upper screen rotating assembly and enter the straight material pipe from the upper material guide pipe;

(7) starting a motor of the lower screen rotating assembly, enabling the lower screen assembly to rotate, and enabling the matrix powder in the straight material pipe to be screened by the lower screen rotating assembly and enter a lower material guide pipe to convey the matrix powder into a die cavity of the preforming die;

(8) after the powder adding is finished, stopping the rotation of the screen, knocking the vibration device to ascend at the same time, and descending the die rotating mechanism;

(9) and the mechanical arm grabbing mechanism moves to output the pre-forming die filled with the graphite matrix powder, and the non-powdered pre-forming die on the preparation position is moved to a powder adding station.

Experimental example 1:

the upper screen mesh is 8 meshes, and the lower screen mesh is 10 meshes; the rotating speed of the mould is 350 r/min; the rotation speed of the screen is 120r/min, and the feeding time is 19 s.

The powder adding amount is controlled by controlling the operation time of a screen motor through a material probe 9, and the error analysis among six stations of 4 experiments is shown in table 1.

TABLE 1 error analysis between six stations in 4 different experiments

	1	2	3	4
					Upper deviation/%)	1.92	1.37	1.13	1.72
Deviation/%)	1.83	1.28	1.11	1.28

Therefore, the rotatable screen assembly is arranged in the powder feeding assembly, so that during the blanking process, the rotation of the screen assembly can ensure that the feeding is as uniform as possible, the quantitative feeding is realized, and the feeding is uniform and loose; in the charging process, the vibration mechanism 10 is knocked at a certain frequency to vibrate and knock the mold while adding powder, so that the powder is uniformly filled in all parts of the mold cavity until the powder is filled in the mold cavity of the whole mold, and the vibration knocking function is to improve the flowability of the powder so that the powder is uniformly distributed around the fuel area and is filled in the whole mold cavity of the mold; meanwhile, the mold rotating mechanism mainly rotates the pre-pressing mold 12 at a certain speed during powder adding, improves the flowability of the powder and enables the powder to uniformly flow to all parts of the mold cavity, and is matched with the knocking vibration mechanism 10 for use, so that the distribution uniformity of the powder in the mold cavity is remarkably improved, and the uniform distribution of the powder is ensured. And the powder adding assembly can be arranged at multiple stations, so that powder adding of a plurality of forming lower dies can be completed at multiple stations, and the production efficiency is obviously improved.

The equipment vibrates and knocks the die at a certain frequency while adding powder, so that the powder is uniformly filled in all parts of the die cavity until the powder is filled in the die cavity of the whole die. The feeding amount and the feeding precision of the materials are controlled by adopting a multistage screen, the rotating speed of the screen and a material sensor at a feeding port at the top of the die, so that the total weight of the materials in the die can be controlled within 2 percent (relative error), the production efficiency is obviously improved, and the feeding efficiency is not lower than 480 parts per hour; through the feeding closure of the rotary screen and the feeding semi-closure of the feeding pipe to the die, the overflow of dust can be effectively reduced, and the production environment of a workshop is better improved.

It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only, and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "including," and "having" are inclusive and therefore specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order described or illustrated, unless specifically identified as an order of performance. It should also be understood that additional or alternative steps may be used.

Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

For convenience of description, spatially relative terms, such as "inner", "outer", "lower", "below", "upper", "above", and the like, may be used herein to describe one element or feature's relationship to another element or feature as illustrated in the figures. Such spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" or "over" the other elements or features. Thus, the example term "below … …" can include both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.