Vertical conveyance, and lower end bearing of inclination-conveying screw conveyor

Abstract

To provide a bearing having a configuration in which a conveyed article is completely sealed off from a rotary part since, in a screw conveyor including a screw in a cylindrical tube, oil-sealing or the like is usually used for preventing conveyed articles from creeping into bearing rotary parts when providing a bearing at a lower end of a screw shaft, but no desired seal effect can be obtained due to fine particles creeping into the rotary part when the conveyed articles are the fine particles or the fine particles are contained in the conveyed articles with the conventional oil-sealing, and no lubricant can be used in the cases where the conveyed articles are food, chemicals and so forth.SOLUTION: A lower end bearing for each of a vertical-conveying conveyor and an inclination-conveying conveyor that have configurations as shown in FIG. 1 and FIG. 3 is realized by utilizing that granules do not exhibit such fluidity as that of water or oil. Conveyed articles deposited below a bearing at an initial operation stage are maintained while keeping an initial state, and thus utilized as a sealant. There is provided a configuration in which disassembly / cleaning can be done by a simple operation procedure as shown in FIG. 5 in order to eliminate the conveyed articles deposited below the bearing as needed.

Description

Technology field

[0001] The present invention relates to a screw conveyor having a screw built into a cylindrical tube for conveying powdery or granular material, and to a lower end bearing for a vertical screw conveyor and an inclined screw conveyor.

[0002] Conventional screw conveyors often have a U-shaped trough in the housing, with a screw attached inside the trough, and are used for short distance horizontal transport, while bucket conveyors are the mainstream for vertical and inclined transport. Definition of screw conveyor as referred to in this proposal

[0003] The proposed screw conveyor is a screw conveyor with a structure in which a screw made of thin, rectangular steel plate wound around a round bar or steel pipe at a predetermined pitch and fixed to it is installed coaxially inside a cylindrical pipe and can easily rotate. (Unless otherwise specified, the term screw conveyor will follow this definition below.) Documents related to the prior art

[0004] References: JP 2000-211725 Powder and granular material transport method and device There are no patents, utility models, or reference books that specifically focus on bottom bearings for vertical and inclined conveying screw conveyors. Summary of the Invention

[0005] In screw conveyors, there are two methods for driving the screw shaft for vertical and inclined conveyance: driving from the top end of the screw shaft or driving from the bottom end of the shaft. Top end driving is generally used because it allows the drive mechanism to be completely isolated from the conveyed goods. (See Figure 6, Top End Driving for Vertical and Inclined Conveyances for reference.) When using a top drive, a bottom bearing is required to ensure smooth rotation of the bottom end of the screw shaft.

[0006] 1. The screw shaft must be able to rotate smoothly without the transported material coming into contact with or penetrating rotating parts such as bearings. 2. Although the material being conveyed accumulates at the bottom of the screw shaft, the amount is limited to a certain amount and can be used as a sealing material. 3. The deposits on the bottom end of the screw shaft must be removed after a long period of operation in which the type of transported material is changed, and the structure must be such that this work can be easily performed.

[0007] As a means for solving the problem, the configuration of the lower end bearing shown in Figure 1 will be explained. Note that the configuration of the lower end bearing is the same for both vertical and inclined conveyance, so only the configuration for vertical conveyance will be explained. (See Figure 3 for the configuration of the lower end bearing for the inclined conveyance screw.)

[0008] As shown in Figure 1, when a vertical conveyor 1 conveys an object upward, the object on the horizontal conveyor 5 is thrust by the horizontal screw 6 and is transported upward by the adjacent vertical screw 1. At this time, the object sent by the horizontal screw conveyor 5 during initial operation accumulates at the lower end of the T-joint 16, which is not reached by the thrust of the horizontal screw 6. To prevent the accumulated object from scattering, a bowl-shaped sealing cup 8 is fixed to the lower end of the vertical screw shaft 2 using a sealing cup fixing plate 9 and a rolling bearing nut 10 to receive the object. The bowl-shaped sealing cup 8 is positioned with a small gap between the bottom and the lower end of the T-joint 16 to prevent contact. Since the fluidity of the powder or granular material being the main transported material is significantly poorer than that of water or oil, leakage will not occur through this gap. The upper layer height limit of the pile is maintained at a constant level, fluctuating slightly, at a position beyond the reach of the horizontal transport thrust. When the pile is below the minimum fluctuating upper layer height, the upper layer height remains stable and downward movement of the pile does not occur beyond this limit, so it is used as a sealing material. The effect of the stainless steel balls 17 is to prevent the accumulated transported materials from adhering to the bottom of the bowl-shaped sealing cup 8 and to facilitate cleaning when disassembled. (The transport status of the transported items is as shown in Figures 2 and 4) Difficulty of disassembly and assembly

[0009] The present invention actively utilizes the materials accumulated on the lower end bearing as a sealing material, and therefore requires periodic removal and cleaning work due to its structure. The work is carried out according to the procedure shown in Figure 5. (a) Appearance of the lower end bearing of the vertical conveying pipe (b) The bearing set screw is loosened, the clamp on the No. 1 125A ferrule is removed, and the spigot round flange unit 11 is removed. (c) No.2 125A ferrule clamp removed and cylindrical cover 13 removed (d) The rolling bearing nut 10 and the bowl-shaped sealing cup 8 are removed. (e) The clamp of No. 3 100A is removed, and the T-joint 16 is pulled downward to expose the lower end of the vertical screw shaft 2.

[0010] The bearing of this invention is designed to be installed in a location completely isolated from the powder or granular material being transported, so it can be used as both a plain bearing and a rolling bearing, and can be used with both lubricated and non-lubricated bearings. In many cases, O-rings and oil seals are used to prevent the transported material from coming into contact with or entering the bearing section, but since no O-rings or oil seals are used, there are no problems associated with these. [Brief explanation of the drawings]

[0011] [Figure 1] Vertical screw conveyor lower end bearing configuration [Figure 2] Vertical screw conveyor transporting powder and granular materials [Figure 3] Configuration of the lower end bearing of an inclined screw conveyor [Figure 4] Powder and granular material transport on an inclined screw conveyor [Figure 5] Disassembly procedure for the lower bearing [Figure 6] Reference diagram: Vertical and inclined transport [Explanation of symbols]

[0012] Regarding the explanation of the symbols, since the configuration of the vertical screw conveyor and the configuration of the inclined screw core of this invention are the same, only the configuration of the vertical conveyor will be described. (See Figure 3 for the configuration of the inclined transport conveyor.) 1 Vertical screw conveyor 2 vertical screw shaft 3 Screw conveyor blades 4 Ferrule for fastening the vertical conveying pipe and T-joint 5 Horizontal screw conveyor 6 horizontal screws 7 Ferrule for fastening the T-joint and horizontal conveying pipe 8 sealing cups 9 Sealing cup fixing plate 10 Rolling bearing nuts 11 Spigot-equipped round flange unit 12 Bearing set screw 13 Cylindrical cover 14 Ferrule for fixing the cylindrical cover 15 Ferrule for mounting round flange unit with spigot 16 T-joint 17 Stainless steel ball

Claims

1. In vertical and inclined conveying screw conveyors, when a bearing is installed at the bottom end of the screw shaft, this bottom end of the screw is where unconveyed materials accumulate, so it is shielded with an O-ring or oil seal to prevent the materials from coming into contact with or penetrating the rotating part of the bearing. However, if the materials are fine particles or contain fine particles, some of them will inevitably enter the rotating part. In order to completely shield the rotating part of the screw shaft from the transported material, a bowl-shaped cup is fixed to the lower end of the screw shaft and rotates in the same direction as the screw shaft. The lower end of a T-joint, which has the same diameter as the vertical transport pipe, is installed with a gap large enough so that it does not come into contact with the inner bottom of the bowl-shaped cup. The inner diameter of the bowl-shaped cup is large enough so that it does not come into contact with the outer diameter of the T-joint, and it catches the transported sediment to prevent leakage or scattering. The transported material does not move downward beyond the sediment layer, so this lower end bearing for vertical and inclined transport screw conveyors has a structure that allows it to be used as a sealant.

2. The bearing section is a cylindrical pipe that is one size larger in diameter than the conveying pipe, and is coaxial with the T-joint, with a length that can accommodate the rolling bearing nuts etc. required to secure the bowl-shaped sealing cup, and its upper end is fastened to the T-joint with a ferrule; a mating ferrule that is fastened to the ferrule fixed to the lower end of the cylindrical pipe is fitted with a plain bearing, rolling bearing or other type of bearing that can be lubricated or not, and this lower end bearing for vertical and inclined conveying screw conveyors has a structure that allows the conveyed material and the bearing section to be completely isolated.

3. It is necessary to periodically remove and clean unconveyed deposits from the bowl-shaped sealing cups. The work of removing the T-joint, cylindrical cover, bowl-shaped sealing cup, etc. to expose the bottom end of the screw shaft involves removing the set screws and other fasteners that secure the bearing to the screw shaft, removing the related ferrule clamp, and removing the rolling bearing nut that secures the bowl-shaped sealing cap. This is the bottom end bearing of a vertical and inclined transport screw conveyor with a simple structure.

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