A screening machine and a screening method

Abstract

A screening machine includes multiple parallel arranged rotating shafts. Each rotating shaft is provided with multiple turntables. The gaps between the turntables on adjacent rotating shafts form screening gaps. Above the rotating shafts, there are a material pouring opening and a moving mechanism for driving the relative displacement between the material pouring opening and the rotating shafts. The present invention also provides a screening method. By adjusting the distance between the material pouring opening of the screening machine and the last rotating shaft, it is ensured that among the materials reaching the last rotating shaft, there are still materials with smaller particles that could have passed through the screening gaps but have not had time to do so. As a result, among the materials on the last rotating shaft, there are still larger particles floating on top of the smaller particles. The advantage of the present invention is that when the screening gaps are worn and enlarged, it is not necessary to replace or delay replacing the turntables, thereby reducing the equipment operation cost, reducing the downtime, and improving the production efficiency.

Description

Technical Field

[0001] The present invention relates to screening equipment and screening methods, and particularly to a screening machine and a screening method for screening ceramic raw materials. Background Art

[0002] In existing screening equipment, there is a screening machine mainly composed of multiple parallel arranged rotating shafts. Each rotating shaft is equipped with multiple spaced-apart turntables. The turntables on two adjacent rotating shafts are inserted into the intervals between the turntables on the other rotating shaft respectively. The gap between two adjacent turntables forms a screening gap for screening materials. All the turntables rotate in the same direction driven by the rotating shafts.

[0003] The working principle of this screening machine is that the same-direction rotation of the turntables causes the materials falling above the rotating shafts to flow along the direction of the arrangement of the rotating shafts, enabling the materials to pass through each rotating shaft. During the flow of the materials, the smaller particles can fall below the rotating shafts through the screening gaps between the turntables, while the larger particles that cannot pass through the screening gaps are thrown out above the last rotating shaft as the materials flow. In this way, the materials are screened into the screened materials below the rotating shafts and the oversize materials thrown out above the last rotating shaft.

[0004] However, the screening gap between the turntables will increase due to the wear of the turntables, allowing larger particles that originally could not pass through the screening gap to also fall below the rotating shafts, resulting in a reduction in screening quality. Therefore, this existing screening machine needs to frequently replace the turntables, which not only increases the operating cost of the equipment but also reduces the production efficiency due to equipment downtime. Summary of the Invention

[0005] The object of the present invention is to overcome the defects of the above-mentioned existing technology and provide a screening machine that can reduce the operating cost of the equipment and improve the production efficiency. The present invention also provides a screening method to solve the same problem.

[0006] The screening machine of the present invention is realized as follows: The screening machine includes multiple parallel arranged rotating shafts. Each rotating shaft is axially equipped with multiple spaced-apart turntables. The turntables on two adjacent rotating shafts are inserted into the intervals between the turntables on the other rotating shaft respectively. The gap between two adjacent turntables forms a screening gap for screening materials. There is a material pouring port above the rotating shafts. The turntables rotate in the same direction so that the materials falling on the rotating shafts flow along the direction of the arrangement of the rotating shafts. There is a moving mechanism that drives the material pouring port to have a relative displacement with respect to the rotating shafts. The distance between the material pouring port and the last rotating shaft changes with this relative displacement. The "last rotating shaft" refers to the last rotating shaft that the materials can reach along the direction of the arrangement of the rotating shafts.

[0007] As an alternative embodiment, in the path where the material flows along the direction of the rotating shaft arrangement, the screening gap between the turntables near the material pouring port is smaller than the maximum particle size of the screened material to be obtained.

[0008] As an alternative embodiment, a spacer sleeve is provided between every two adjacent turntables on the same rotating shaft, and the spacer sleeve is sleeved on the rotating shaft.

[0009] On the other hand, the screening method of the present invention is realized as follows: using the screening machine provided by the present invention, the material to be screened is poured from the material pouring port onto the rotating shaft, and the material with smaller particles falls below the rotating shaft through the screening gap. The same-direction rotation of the turntables is utilized to make the material flow along the direction of the rotating shaft arrangement on the rotating shaft. By using the phenomenon that the material with larger particles tumbles and floats above the material with smaller particles during the flow of the material on the rotating shaft, the distance between the material pouring port and the last rotating shaft is adjusted so that when the material on the rotating shaft flows to the last rotating shaft, there are still materials with smaller particles that could have passed through the screening gap but have not had time to pass through the screening gap. As a result, there are still materials with larger particles floating above the materials with smaller particles in the material on the last rotating shaft.

[0010] The advantage of the present invention is that since the distance between the material pouring port and the last rotating shaft is adjustable, the distance can be adjusted to ensure that there are still materials with larger particles floating above the materials with smaller particles when the material flows to the last rotating shaft. Therefore, even if the screening gap increases due to the wear of the turntable, the materials with larger particles will be blocked by the materials with smaller particles below and cannot pass through the enlarged screening gap. In this way, the screening machine can still operate without replacing or delaying the replacement of the turntable, or at least delaying the replacement of the turntables on several rotating shafts near the last rotating shaft, thereby reducing the equipment operation cost, reducing the downtime, and improving the production efficiency. Description of the Drawings

[0011] Figure 1 is a schematic structural diagram of an embodiment of the screening machine of the present invention;

[0012] Figure 2 is from Figure 1 the top view direction, that is, a schematic diagram of two rotating shafts and the turntables on the rotating shafts seen from the top view direction of the screening machine;

[0013] Figure 3 is a schematic diagram of the working state of the screening machine before the screening gap is worn and enlarged;

[0014] Figure 4 is a schematic diagram of the working state of the screening machine after shortening the distance between the material pouring port and the last rotating shaft. Detailed implementation mode

[0015] For the convenience of understanding the present invention, the present invention will be described more comprehensively below with reference to the accompanying drawings. The preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0016] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element present at the same time, unless otherwise specifically stated herein.

[0017] It should be noted that when an element is considered to be "fixed" to another element, it can be fixed in a detachable connection manner or may be fixed in a non-detachable connection manner, unless otherwise specifically stated herein.

[0018] The screening machine according to the present invention is as Figure 1 shown, including a plurality of parallel arranged rotating shafts 1, and a plurality of spaced-apart turntables 2 are axially installed on each rotating shaft. All the turntables 2 rotate in the same direction under the drive of the rotating shaft 1. In Figure 1 the example, all the turntables 2 rotate counterclockwise. A material pouring port 3 is provided above the rotating shaft 1. The material to be screened is poured from the material pouring port 3 onto the rotating shaft 1.

[0019] As Figure 2 shown, the turntables 2 on every two adjacent rotating shafts 1 are inserted into the intervals between the turntables on the other rotating shaft, and the gap between every two adjacent turntables 2 forms a screening gap for screening the material.

[0020] The screening machine is further provided with a moving mechanism for driving the material pouring port 3 to make a relative displacement with the rotating shaft 1. Figure 1 In the shown embodiment, a circulating belt 4 driven by a motor to reciprocate is used as the moving mechanism. The circulating belt 4 drives the material pouring port 3 to move in the Figure 1 left and right directions, so as to change the distance between the material pouring port 3 and the last rotating shaft 1a. The last rotating shaft 1a refers to the last rotating shaft that the material can reach along the arrangement direction of the rotating shafts.

[0021] The moving mechanism is not limited to a reciprocating circulating belt. For example, a cylinder or a hydraulic cylinder driving mechanism can also be used, and the cylinder or the hydraulic cylinder drives the material pouring port 3 to reciprocate, or a linear motor or a rack and pinion mechanism can also be used to drive the material pouring port 3 to reciprocate.

[0022] It should be noted that the structural manner in which the material discharge port 3 and the rotating shaft 1 have relative displacement can also be that the material discharge port 3 remains stationary and all the rotating shafts 1 move together, or it can also be that the material discharge port 3 and all the rotating shafts 1 move relatively together. For example, all the rotating shafts 1 are installed on the same moving bracket, and the moving mechanism drives the moving bracket to reciprocate, thereby changing the distance between the material discharge port 3 and the last rotating shaft 1a.

[0023] The screening method described in the present invention uses the screening machine provided by the present invention. Specifically, as Figure 3 shown, the material to be screened is discharged from the material discharge port 3 onto the rotating shaft 1, and the same-direction rotation of all the turntables 2 causes the material to flow immediately along the direction of the arrangement of the rotating shafts after being discharged onto the rotating shaft 1. While the material is flowing, the smaller particles of the material fall under the action of gravity through the screening gaps between the turntables to form the screened material below the rotating shaft 1.

[0024] Before the turntable 2 wears, as Figure 3 shown, the larger particles of the material are thrown out from above the last rotating shaft 1a along with the flow of the material because they cannot pass through the screening gaps between the turntables. The thrown larger particles of the material are separated from the screened material that has fallen directly below the rotating shaft.

[0025] When the turntable 2 wears and causes the screening gap to increase, the larger particles of the material will fall through the screening gap below the rotating shaft. To avoid this situation, the method of the present invention utilizes the phenomenon that the larger particles of the material roll up and float above the smaller particles of the material during the flow of the material on the rotating shaft, and adjusts the distance between the material discharge port 3 and the last rotating shaft 1a. As Figure 3 shown, shorten the distance between the material discharge port 3 and the last rotating shaft 1a, so that when the material on the rotating shaft 1 flows to the last rotating shaft 1a, there are still smaller particles of the material that could have passed through the screening gap but have not had time to pass through the screening gap, so that there are still larger particles of the material floating above the smaller particles of the material among the materials reaching above the last rotating shaft 1a. In this way, even if the screening gap has worn and increased, the larger particles of the material will be blocked by the smaller particles of the material below and cannot pass through the screening gap, and finally can only be thrown out from above the last rotating shaft 1a together with a small amount of smaller particles of the material. Figure 4

[0026] It should be noted that the timing of adjusting the distance between the material discharge port 3 and the last rotating shaft 1a can be either to make the adjustment after the screening machine has worked for a period of time, or to make the adjustment when the screening machine starts to work and the turntable has not yet worn, so as to ensure that there are always larger particles of the material floating above the smaller particles of the material among the materials reaching the last rotating shaft throughout the working process of the screening machine.

[0027] Since the phenomenon that larger particles in the material tumble and float above smaller particles only occurs during the flow of the material, therefore, the turntables on several rotating shafts close to the material discharge port 3 still need to be replaced in a timely manner after wear, because the large particles have not had time to float up when passing through these several rotating shafts.

[0028] To solve this problem, the present invention further improves the screening machine. In the path where the material flows along the direction of the rotating shaft arrangement, the screening gap between the turntables in the front part of the path close to the material discharge port 3 is set to be smaller than the maximum particle size of the screened material to be obtained. For example, assuming that it is required to screen out materials with a maximum particle size not exceeding 0.5 mm from a batch of materials, then 0.5 mm is the maximum particle size of the screened material to be obtained. In this case, the screening gap between the turntables in the rear part of the material flow path of the screening machine is normally set to 0.5 mm, while the screening gap between the turntables in the front part of the path close to the material discharge port 3 is set to be less than 0.5 mm, for example, set to 0.3 mm. In this way, the replacement cycle of the turntables in the front part of the path can be extended, and even if these turntables are worn, they do not need to be replaced immediately, reducing the frequency of replacing the turntables.

[0029] As for how much smaller the screening gap between the turntables should be than the maximum particle size of the screened material to be obtained, there is no strict limit. The larger this difference is, the longer the replacement cycle of the turntables and the fewer the replacement frequencies.

[0030] As for how many rotating shafts specifically need to have the screening gap between their turntables set to be smaller than the maximum particle size of the screened material to be obtained, it should be determined according to the material flow rate in actual production. The best design is that as long as the large particles have not had time to float up when passing through several rotating shafts, then the screening gap between the turntables of these several rotating shafts should be smaller than the maximum particle size of the screened material to be obtained. Taking Figure 4 as an example, the screening gap between the turntables of the three rotating shafts on the right should be set to be smaller than the maximum particle size of the screened material to be obtained, because the large particles have not had time to float up when passing through these three rotating shafts.

[0031] To facilitate the adjustment of the screening gap between the turntables, as Figure 2 shown, a spacer sleeve 5 is provided between every two adjacent turntables 2 on each rotating shaft 1, and the spacer sleeve 5 is sleeved on the rotating shaft 1. By replacing spacer sleeves 5 of different lengths, the interval between the turntables 2 can be adjusted, that is, the screening gap between the turntables can be adjusted.

[0032] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the protection scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several variations and improvements can still be made, and these all fall within the protection scope of the present invention. The protection scope of the invention patent shall be subject to the appended claims.

Claims

1. A screening machine, comprising a plurality of parallel arranged rotating shafts, each rotating shaft is axially provided with a plurality of spaced-apart turntables, the turntables on each two adjacent rotating shafts are inserted into the spaces between the turntables on the other rotating shaft, the gap between each two adjacent turntables forms a screening gap for screening materials, a material pouring port is provided above the rotating shafts, the turntables rotate in the same direction so that the materials falling on the rotating shafts flow along the direction of the arrangement of the rotating shafts, and the characteristics are as follows: A moving mechanism is provided to drive the relative displacement between the material discharge opening and the rotating shaft. The distance between the material discharge opening and the last rotating shaft changes with this relative displacement. The last rotating shaft refers to the last rotating shaft that the material can reach along the direction of the arrangement of the rotating shafts. In the path of the material flowing along the direction of the arrangement of the rotating shafts, the screening gap between the turntables close to the material discharge opening is smaller than the maximum particle size of the screened material required to be obtained.

2. The screening machine according to claim 1, wherein: A spacer sleeve is provided between every two adjacent turntables on the same rotating shaft, and the spacer sleeve is sleeved on the rotating shaft.

3. A screening method, wherein: Using the screening machine according to claim 1, the material to be screened is discharged from the material discharge opening onto the rotating shaft. The material with smaller particles falls below the rotating shaft through the screening gap. By using the same-direction rotation of the turntables, the material flows on the rotating shaft along the direction of the arrangement of the rotating shafts. During the process of the material flowing on the rotating shaft, the phenomenon that the material with larger particles tumbles and floats above the material with smaller particles occurs. Adjust the distance between the material discharge opening and the last rotating shaft so that when the material on the rotating shaft flows to the last rotating shaft, there is still some material with smaller particles that could have passed through the screening gap but has not had time to do so. As a result, there are still some materials with larger particles floating above the materials with smaller particles in the material on the last rotating shaft.

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