Patent Description:
There are scenes of conveying powder materials in industrial production. Taking a cement-producing process as an example, feeding and batching steps for powder materials such as coal powder, raw material powder, mineral powder, flyash, and kiln dust are included. An impeller feeder, a spiral conveyor, a rotor scale or the like are generally used in these steps to achieve metered delivery of powder materials. Due to technology or the feeding device itself, the process of delivering the powder materials is prone to problems such as feeding fluctuations such as material flush and interruption of feeding.

For example, due to the limitations of structural form of the impeller feeder, size of an inlet of the impeller feeder is limited so that the amount of the powder materials received by it is small, the interruption of feeding is liable to occur. As a result, uneven reception of the powder materials causes large fluctuation. Furthermore, there is only one blade participating material retention between a bin of the impeller feeder and the impeller, and a gap between the blades and a cylindrical wall of the bin is too large. These problems cause an undesirable material retaining effect. The spiral conveyor is also confronted with problems such as a small opening of the inlet and undesirable material-retaining effect between spiral blades. Due to the structural form of the rotor scale, the inlet of the rotor scale can only be laterally provided on one side, and the rotor scale is also confronted with problems such as a small amount of received powder materials, likelihood to interruption of feeding and even large feeding fluctuations.

There are further some processes of delivering powder materials in a positive pressure pneumatic delivery manner downstream the feeding device. A delivery air flow is likely to blow reversely into the feeding device so that the powder materials cannot smoothly enter a downstream delivery step, but circulate in the feeding device or pile up at an outlet of the feeding device. This causes a deviation to exist between an actual amount of delivered materials and an amount of delivered materials as displayed by the feeding device, thereby causing feeding fluctuations.

Therefore, it is necessary to provide a stabilizing flow feeder which at least partially solves the above problems.

<CIT> discloses features falling under the preamble of claim <NUM>. <CIT> and <CIT> are further prior art.

An objective of the present disclosure is to provide a stabilizing flow feeder to solve problems about feeding fluctuations such as material flush or interruption of feeding during delivery of powder material.

According to an aspect of the present disclosure, the stabilizing flow feeder comprises:.

According to the present solution, the agitating device may allow the powder material to maintain fluidity and avoid dead spots caused by pile-up. Furthermore, the flow-assisting air generated by the air flow-assisting device may overcome a reverse blow action exerted by the delivery air flow of a delivery device located downstream of the stabilizing flow feeder so that the powder material can smoothly enter the downstream delivery device from the stabilizing flow feeder, thereby making the powder material flow stably and evenly, reducing the feeding fluctuations and making the metering of the delivery amount accurate.

In an embodiment, the agitating device comprises an agitating shaft and at least two sets of agitating rods extending radially with the agitating shaft as a center, wherein the agitating rods in different sets are disposed spaced-apart in a height direction of the vertical axis.

With the present solution, the agitating rods spaced apart in the height direction may enhance the overall agitating effect.

In an embodiment, an end of the agitating rod is provided with a wall scraping plate perpendicular to the agitating rod.

With the present solution, the wall scraping plate may sweep and scrape the powder material adhered to the side wall of the agitating bin.

In an embodiment, the agitating rod and/or the wall scraping plate are provided with a resistance reducing structure on their respective front sides in a rotation direction.

With the present solution, the resistance reducing structure may reduce the resistance upon rotation of the agitating device.

In an embodiment, a sweeping device capable of rotating around the vertical axis is further provided in the agitating bin, the sweeping device is disposed below the agitating device and includes sweeping blades disposed symmetrically about the vertical axis, and the sweeping blades abut against a bottom wall of the agitating bin.

With the present solution, the sweeping device may sweep the powder material on the bottom wall of the agitating bin at a position opposed to the inlet of the feeding bin in the radial direction perpendicular to the vertical axis into the feeding bin, to avoid the dead spots caused by pile-up of the powder material, and the sweeping blades may also function to agitate the powder material to maintain fluidity to a certain degree.

In an embodiment, the sweeping device comprises a sweeping sleeve, and the sweeping blades are connected to the sweeping sleeve and extend radially with the sweeping sleeve as a center.

With the present solution, the structure of the sweeping device is simple and easy to implement.

In an embodiment, the feeding impeller comprises:.

With the present solution, the fan-shaped or fan annular-shaped section is formed between the blades of the feeding impeller to better receive the powder material.

In an embodiment, gaps between the feeding impeller and a bottom wall, a top wall and a side wall of the feeding bin are not greater than <NUM>.

With the present solution, the above gaps are small, and the powder material may fill therein to play a shielding role to avoid the running of the powder material and air through the bin, so an excellent material retaining effect is provided.

In an embodiment, an opening angle of the inlet in a circumferential direction around the vertical axis is in a range of <NUM>° to <NUM>°, and/or a size of the inlet in a radial direction perpendicular to the vertical axis is in a range of <NUM> to <NUM>.

With the present solution, the inlet has a large size to allow more powder material to pass therethrough simultaneously, avoid the case of interruption of feeding and ensure the powder material filling rate of the feeding impeller.

According to the invention, the stabilizing flow feeder comprises at least two feeding bins which are disposed stacked in an up-and-down direction, the outlet of an upper feeding bin is communicated with the inlet of a lower feeding bin, and the flow-assisting air path is disposed in the lowermost feeding bin.

With the present solution, the plurality of feeding bins disposed stacked may significantly reduce a reverse blow action of the reversely-blown air flow and further improve the material-retaining effect.

In an embodiment, an air flow passage is disposed in a top wall of the lowermost feeding bin of the stabilizing flow feeder, air outlets communicated with the air flow passage are disposed at a position of the top wall aligned with the outlet, and the air flow passage and the air outlets constitute at least a portion of the flow-assisting air path.

With the present solution, the flow-assisting air path is formed by the air flow passage and air outlets in the top wall, and may make the structure compact and avoid interference with the rotary motion of the feeding impeller.

The present invention can well solve the problem of interruption of feeding due to undesirable fluidity of the powder material, and solve the problem of material flush due to excessive fluidity.

For the sake of better understanding on the above and other objectives, features, advantages, and functions of the present disclosure, the preferred embodiments are provided with reference to the drawings. The same reference symbols refer to the same components throughout the drawings. It would be appreciated by those skilled in the art that the drawings are merely provided to illustrate preferred embodiments of the present disclosure, without suggesting any limitation to the protection scope of the present disclosure, and respective components therein are not necessarily drawn to scale.

Reference now will be made to the drawings to describe embodiments of the present disclosure. What will be described herein are only preferred embodiments according to the present disclosure. On the basis, those skilled in the art would envision other embodiments of the present disclosure which all fall into the scope of the present disclosure.

The present disclosure provides a stabilizing flow feeder for delivering powder material. For example, the stabilizing flow feeder may be used for steps of feeding and batching powder materials such as coal powder, raw material powder, mineral powder, flyash, and kiln dust during production of cement, so as to solve problem about feeding fluctuations such as interruption of feeding or material flush during delivery of the powder material.

As shown in <FIG>, the stabilizing flow feeder <NUM> according to a first example includes an agitating bin <NUM>, a feeding bin <NUM>, an air flow-assisting device <NUM> and a driving device <NUM>.

The agitating bin <NUM> is configured as a cylindrical structure as a whole, with an agitating bin opening <NUM> disposed on the top thereof and an agitating bin inspection port <NUM> disposed on the lateral side. The feeding bin <NUM> is located below the agitating bin <NUM>, and the top of the feeding bin <NUM> is provided with an inlet <NUM> communicated with the bottom of the agitating bin <NUM>. The agitating bin <NUM> may receive incoming material through the agitating bin opening <NUM>, and then delivers the material to the feeding bin <NUM>, acting as a buffer between a source of the powder material and the feeding bin <NUM> to ensure that the feeding bin <NUM> offers continuous and stable supply of the powder material. Preferably, the cross sections of the agitating bin opening <NUM> and the internal space of the agitating bin <NUM> are approximately the same, so that a straight-through feeding cylinder is formed. In this way, the size of the agitating bin opening <NUM> can be increased to a maximum extent, thereby increasing the amount of powder received by the agitating bin <NUM>, stabilizing the incoming material, and reducing the possibility of the interruption of feeding.

Generally, the agitating bin <NUM> has a vertical axis AX. The following depictions are presented by taking a direction along the vertical axis as a height direction and taking a direction perpendicular to the vertical axis as a radial direction. The powder material at a position in the agitating bin <NUM> facing exactly the inlet <NUM> of the feeding bin <NUM> and its surrounding area easily enter the feeding bin through the inlet <NUM>. The powder material at positions away from the inlet <NUM>, particularly the powder material at a position opposed to the inlet <NUM> in the radial direction is apt to pile up to form a dead spot. The piled powder occupies the space in the agitating bin <NUM>, and reduces the fluidity of the powder material so that the feeding conditions become poor. Hence, an agitating device <NUM> is disposed in the agitating bin <NUM>. The agitating device <NUM> may rotate about the vertical axis AX of the agitating bin <NUM> and agitate the powder material in the agitating bin <NUM>. Through agitation, the powder material may maintain excellent fluidity in the agitating bin <NUM> to facilitate delivery, thereby avoiding occurrence of unfavorable conditions such as dead spots and agglomeration caused by the pile-up of the powder material at positions away from the inlet <NUM>.

As shown in <FIG>, the agitating device <NUM> includes an agitating shaft <NUM> and an agitating rod <NUM>. Wherein, the agitating shaft <NUM> is vertically disposed in the agitating bin <NUM> and defines the vertical axis AX. The agitating rod <NUM> is connected to the agitating shaft <NUM> and extends radially with the agitating shaft <NUM> as a center. Preferably, in the illustrated example, the agitating device <NUM> includes two sets of agitating rods <NUM>. Each set includes two agitating rods <NUM> arranged symmetrically about the vertical axis AX. The agitating rods <NUM> in the same set are located in the same horizontal plane, and the agitating rods <NUM> in different sets are spaced in the height direction. As such, the powder materials at different height positions in the agitating bin <NUM> may be stirred, and the agitating effect can be optimized. Preferably, the agitating rods <NUM> of different sets are staggered in the circumferential direction around the vertical axis AX. Such an arrangement enables simultaneous agitation of the powder material at different circumferential positions, so that the agitation is more uniform, and the effect is more obvious especially when the number of agitating rods <NUM> in each set is small. It may be appreciated that in other embodiments, the agitating device may include three or more sets of agitating rods, and/or each set may include three or more agitating rods, and the number of agitating rods in different sets may be the same or different.

Preferably, the agitating device <NUM> further includes a wall scraping plate <NUM>. The wall scraping plate <NUM> is disposed at an end of the agitating rod <NUM> and is perpendicular to the agitating rod <NUM>. When the agitating device <NUM> rotates around the vertical axis AX, the wall scraping plate <NUM> may scrape the powder material adhered to the inner wall surface of the agitating bin <NUM> through a larger contact area than the agitating rod <NUM> to prevent the powder material from adhering to the inner wall surface and piling up to form the dead spots.

Preferably, the agitating rods <NUM> and the wall scraping plate <NUM> are all provided with a resistance reducing structure <NUM> on a front side in the rotation direction to reduce the resistance caused by the powder material to the agitating device <NUM>, the resistance reducing structure having a thickness gradually reducing in the rotation direction. In the illustrated example, the resistance reducing structure <NUM> is specifically a chamfered structure disposed on the agitating rods <NUM> and the wall scraping plate <NUM>. It can be understood that, in other embodiments, the resistance reducing structure may also be a structure such as a separately manufactured elongated triangular prism and fixed to the agitating rod or the wall scraping plate. Certainly, it is also possible to provide the above-mentioned resistance reducing structure only on one of the agitating rod and the wall scraping plate.

Further, a sweeping device <NUM> capable of rotating around the vertical axis AX is also provided in the agitating bin <NUM>. Referring to <FIG> and <FIG>, the sweeping device <NUM> including a sweeping sleeve <NUM> and a sweeping blade <NUM> is disposed below the agitating device <NUM>. The sweeping sleeve <NUM> defines a rotation axis of the sweeping device <NUM>, and the rotation axis coincides with the vertical axis AX. That is, the sweeping sleeve <NUM> and the agitating shaft <NUM> of the agitating device <NUM> are arranged coaxially. The sweeping blade <NUM> is connected to the sweeping sleeve <NUM> and extends radially relative to the rotation axis defined by the sweeping sleeve <NUM>. The sweeping blade <NUM> abuts against a bottom wall of the agitating bin <NUM>. Upon rotation, the sweeping device <NUM> may sweep the powder material on the bottom wall of the agitating bin <NUM> at a position opposed to the inlet <NUM> of the feeding bin <NUM> in the radial direction into the feeding bin <NUM>, to avoid the dead spots caused by the pile-up of the powder material. Furthermore, the sweeping device <NUM> may also perform the same agitating function as the agitating device <NUM> to a certain extent. Preferably, the sweeping blades <NUM> are symmetrically arranged around the rotation axis. In the illustrated example, the sweeping device <NUM> includes four sweeping blades <NUM> arranged at a <NUM>° interval therebetween. Preferably, the sweeping blades <NUM> are in the shape of an elongated plate, with the surface of the plate being parallel to the vertical axis AX. A reinforcing rib <NUM> is disposed on one or both sides of the surface of the plate to increase its structural strength.

An internal space of the agitating bin <NUM> and an internal space of the feeding bin <NUM> are spaced apart by a feeding bin top wall <NUM>, and the two spaces are communicated through the inlet <NUM> provided on the feeding bin top wall <NUM>. That is, the feeding bin top wall <NUM> is simultaneously the bottom wall of the agitating bin <NUM>, and the inlet <NUM> is simultaneously the outlet of the agitating bin <NUM>. Such an arrangement can make the structure simpler and more compact.

As shown in <FIG>, the bottom of the feeding bin <NUM> is provided with an outlet <NUM> which is staggered from the inlet <NUM> in the circumferential direction around the vertical axis AX. In the preferred example shown in <FIG>, the outlet <NUM> and the inlet <NUM> are radially opposite. Furthermore, a feeding impeller <NUM> capable of rotating around the vertical axis AX is disposed in the interior of the feeding bin <NUM> and used for transferring the powder material falling from the inlet <NUM> to the outlet <NUM> and delivering the powder material to a target position, for example, to other conveying devices downstream of the stabilizing flow feeder. A discharge pipe <NUM> docked with the outlet <NUM> is disposed below the feeding bin <NUM> to facilitate the docking with a powder material receiving device and prevent the powder material from leaking and escaping to the external and causing dust pollution. A discharge pipe inspection port <NUM> is provided on a lateral side of the discharge pipe <NUM>.

As shown in <FIG>, the feeding impeller <NUM> includes an impeller sleeve <NUM>, a blade <NUM> and a rim <NUM>. The impeller sleeve <NUM> is coaxially arranged with the sweeping sleeve <NUM> of the sweeping device <NUM> and the agitating shaft <NUM> of the agitating device <NUM>, and the three jointly define the vertical axis AX. The blade <NUM> includes a plurality of blades which are connected to the impeller sleeve <NUM> and extend radially outward with the impeller sleeve <NUM> as the center. The rim <NUM> connects the ends of adjacent blades <NUM>. Two adjacent blades <NUM>, the impeller sleeve <NUM>, and the rim <NUM> collectively surround a substantially fan-shaped section or fan annular section (hereinafter collectively referred to as "section"). When the feeding impeller <NUM> rotates, the powder material falling from the inlet <NUM> enters the section and rotates with the feeding impeller <NUM>, and when the section is aligned with the outlet <NUM>, the powder material falls from the outlet <NUM> to complete the feeding. Preferably, the plurality of blades <NUM> are evenly spaced apart in the circumferential direction around the vertical axis AX. Therefore, each section has approximately the same volume. With this arrangement, the amount of powder material conveyed by the stabilizing flow feeder can be adjusted by adjusting the rotation speed of the feeding impeller <NUM>, and accurate metering can be achieved.

The inlet <NUM> is preferably set with a larger size, so that the amount of powder material entering the feeding bin <NUM> is stable and sufficient. The stable supply of the incoming material into the feeding bin <NUM> facilitates keeping the powder material filling rate in each section of the feeding impeller <NUM> stable. In one embodiment, the opening size of the inlet <NUM> in the radial direction perpendicular to the vertical axis AX may be set to <NUM> to <NUM>. Further preferably, the opening size of the inlet <NUM> in a radial direction may be set to <NUM> to <NUM>, and specifically may be <NUM>, <NUM>, <NUM>, or the like. The opening angle of the inlet <NUM> in a circumferential direction around the vertical axis AX may be set to <NUM>° to <NUM>°, and specifically may be <NUM>° or <NUM>°.

In some working conditions, a delivery device located downstream of the stabilizing flow feeder delivers the powder material in a positive pressure pneumatic delivery manner. Therefore, a delivery air flow is prone to be blown reversely through the outlet <NUM> into the feeding bin <NUM>. The powder material is liable to transfer between different sections under the blowback air flow, which leads to situations such as material flush and running of the powder material through the bin. Preferably, in the present example, the gap between the feeding impeller <NUM> and the feeding bin top wall <NUM>, a feeding bin bottom wall <NUM> and a feeding bin side wall <NUM> is not greater than <NUM>. The small gap allows the powder material to be filled therein, achieving a shielding effect, so that the powder material can be retained in the sections, and the material flush and the running of the powder material through the bin can be reduced. This facilitates the feeding impeller <NUM> to maintain a uniform feed amount.

Further, the stabilizing flow feeder <NUM> further includes an air flow-assisting device <NUM> which is in air communication with the internal space of the feeding bin <NUM>, and which has a flow-assisting air path disposed on top of the feeding bin <NUM>. The flow-assisting air path is capable of generating, from above the outlet <NUM>, a flow-assisting air flowing outward through the outlet <NUM>. Therefore, when the section of the feeding impeller <NUM> moves past the outlet <NUM>, the flow-assisting air acts on the powder material in the section, and the acting force may be superimposed with gravity to provide the powder material with a downward initial velocity to overcome an upward blowback action generated by the delivery air flow of the downstream delivery device through the outlet <NUM>, so that the powder material can smoothly enter the downstream delivery device from the stabilizing flow feeder, such that the stabilizing flow feeder feeds stably and the feeding metering is accurate. The flow-assisting air path may be communicated with an air source such as an air compressor to generate the above flow-assisting air.

As shown in <FIG>, the feeding bin top wall <NUM> is provided with an air flow passage <NUM>, and a plurality of air outlets <NUM> communicated with the air flow passage <NUM> are disposed at a position of the feeding bin top wall <NUM> aligned with the outlet <NUM>. The plurality of air outlets <NUM> are preferably arranged evenly relative to the outlet <NUM>, so that the flow-assisting air blown out of the air outlets is applied more evenly to the powder material. The air flow-assisting device <NUM> generates the flow-assisting air from the air outlets <NUM> through the air flow channel <NUM> toward the outlet <NUM>. In other words, the air flow passage <NUM> and the air outlets <NUM> constitute at least a portion of the flow-assisting air path of the air flow-assisting device <NUM>, that is, at least a portion of the flow-assisting air path is disposed in the feeding bin top wall <NUM>. As such, it is possible to avoid directly disposing the flow-assisting air path in the internal space of the feeding bin <NUM>, avoiding interference between the flow-assisting air path from and the rotation of the feeding impeller <NUM>, which facilitates reducing the gap between the feeding impeller <NUM> and the feeding bin top wall <NUM>, and makes the structure compact.

The driving device <NUM> is disposed below the feeding bin <NUM>. In the illustrated example, the driving device <NUM> is configured as an electric motor. The driving device <NUM> is coupled to the driving sleeve <NUM>, and the driving sleeve <NUM> is coupled to the driving spindle <NUM> in the feeding bin <NUM>. The impeller sleeve <NUM> of the feeding impeller <NUM> is sleeved on the driving spindle <NUM>. The driving spindle <NUM> further extends into the agitating bin <NUM>, the sweeping sleeve <NUM> of the sweeping device <NUM> is sleeved on the driving spindle <NUM>, and the agitating shaft <NUM> of the agitating device <NUM> is coupled to the driving spindle <NUM>. As such, the transmission connection between the driving device <NUM> and the feeding impeller <NUM>, the sweeping device <NUM> and the agitating device <NUM> is realized.

<FIG> shows a stabilizing flow feeder <NUM> according to a first embodiment of the present invention. Except for the structure of a feeding bin <NUM>, the stabilizing flow feeder <NUM> according to the first embodiment has substantially the same configuration as the stabilizing flow feeder <NUM> according to the first example, wherein the same function structures are denoted by the same reference signs. For the sake of brevity, only the distinguishing features will be introduced in detail, and the similarities will not be repeated.

In the first embodiment, the stabilizing flow feeder <NUM> includes at least two feeding bins <NUM>. The at least two feeding bins <NUM> are stacked in an up-and-down direction. In the two adjacent feeding bins <NUM>, the outlet of the upper feeding bin <NUM> is communicated with the inlet of the lower feeding bin <NUM>. The inlet of the uppermost feeding bin <NUM> is communicated with the agitating bin <NUM>. The flow-assisting air path (including the air flow passage <NUM> and the air outlets <NUM>) of the air flow-assisting device <NUM> is disposed on the top of the lowermost feeding bin <NUM>.

Specifically, as shown in <FIG>, the stabilizing flow feeder <NUM> includes two feeding bins <NUM>. The internal spaces of the upper and lower feeding bins <NUM> are partitioned by a feeding bin partition plate <NUM>, and are communicated through a partition plate opening <NUM> on the feeding bin partition plate <NUM>. In other words, the feeding bin partition plate <NUM> simultaneously serves as the bottom wall of the upper feeding bin <NUM> and the top wall of the lower feeding bin <NUM>, and the partition plate opening <NUM> simultaneously serves as the outlet of the upper feeding bin <NUM> and the inlet of the lower feeding bin <NUM>. Such an arrangement may make the structure simpler and more compact. Furthermore, such an arrangement may avoid the impact on the passing area of the powder material caused by failure of complete alignment of the outlet and the inlet due to different shapes of the outlet of the upper feeding bin <NUM> and the inlet of the lower feeding bin <NUM> or nonalignment of angles by which the outlet and inlet are disposed, and facilitate enabling the powder material to smoothly flow and transfer between multiple layers of feeding bins <NUM>.

Multiple layers of feeding bins <NUM> are provided, and the inlet and outlet of each feeding bin <NUM> are staggered, which forms a meandering air flow path in the feeding bin <NUM>. The pressure of the air flow that is blown back into the feeding bin <NUM> through the lowermost outlet <NUM> gradually reduces as the air flows along the air flow path. At the same time, the amount of powder material contained in the feeding bin <NUM> increases, which creates a greater resistance to the blown-back air flow. Therefore, the stabilizing flow feeder according to the first embodiment can better alleviate phenomena such as material flush and running of the powder material through the bin, providing a better material-retaining effect, being adapted for an occasion with a higher material-retaining requirement upon delivery of the powder material with air.

Claim 1:
A stabilizing flow feeder, wherein the feeder comprises:
an agitating bin (<NUM>) provided with an upward opening (<NUM>) at the top and configured to receive powder material, an agitating device (<NUM>) rotatable about a vertical axis of the agitating bin (<NUM>) being disposed in an interior of the agitating bin (<NUM>);
a feeding bin (<NUM>) located below the agitating bin (<NUM>), a top of the feeding bin (<NUM>) being provided with an inlet communicated with a bottom of the agitating bin (<NUM>), a bottom of the feeding bin (<NUM>) being provided with an outlet (<NUM>), an interior of the feeding bin (<NUM>) being provided with a feeding impeller (<NUM>) rotatable about the vertical axis, the inlet and the outlet (<NUM>) being staggered in a circumferential direction around the vertical axis;
a driving device (<NUM>) configured to drive the agitating device (<NUM>) and the feeding impeller (<NUM>) to rotate; and
an air flow-assisting device (<NUM>) having a flow-assisting air path (<NUM>, <NUM>) disposed in a top wall of the feeding bin (<NUM>), the flow-assisting air path being air-communicated with the feeding bin (<NUM>) and configured to generate, from above the outlet (<NUM>), a flow-assisting air flowing outward through the outlet (<NUM>),
characterized in that
the stabilizing flow feeder comprises at least two feeding bins (<NUM>) which are disposed stacked in an up-and-down direction, the outlet of an upper feeding bin (<NUM>) is communicated with the inlet of a lower feeding bin (<NUM>), and the flow-assisting air path (<NUM>, <NUM>) is disposed in the lowermost feeding bin.