Shaftless screw blades and shaftless screw conveying device

Abstract

To provide a shaftless screw blade and a shaftless screw conveying device that prevent blade breakage for longer periods than conventional methods. [Solution] The shaftless screw blade 1 comprises a shaftless screw blade body 10, a flange 20 fixed to the base end 10a of the shaftless screw blade body 10, at least one reinforcing rib 30 that fixes the flange 20 to the shaftless screw blade body 10, and at least one reinforcing member 40 provided on the shaftless screw blade body 10 such that one end 40a is positioned on the tip 10e side of the shaftless screw blade body 10, rather than on the fixing portion 10d of the shaftless screw blade body 10 to which the reinforcing rib 30 is fixed.

Description

Technical Field

[0001] The present invention relates to a shaftless screw blade and a shaftless screw conveyor device.

Background Art

[0002] Conventionally, for example, a shaftless screw blade includes a shaftless screw blade body, a flange fixed to the proximal end of the shaftless screw blade body, and at least one reinforcing rib that fixes the flange and the shaftless screw blade body. The shaftless screw conveyor device includes a shaftless screw blade, a casing that houses the shaftless screw blade therein, a trough disposed on the inner surface of the casing, and a drive unit connected to the flange of the shaftless screw blade (for example, Patent Document 1).

[0003] When the conveyed material quantity is appropriate, although a certain amount of deflection occurs in the shaftless screw blade body, the deflection is absorbed within the play space in the trough, so the rotation of the blade is maintained and conveyance is also performed.

[0004] By the way, at the fixed portion of the screw blade body to which one end of the reinforcing rib is fixed, since the other end of the reinforcing rib is fixed to the flange, deflection is less likely to occur than at the portion of the screw blade that is not fixed. Therefore, a difference in the ease of deflection occurs between the fixed portion and the tip side of the shaftless screw blade body relative to the fixed portion in the shaftless screw blade body. As a result, the deflection (movement) of the shaftless screw blade body suddenly stops deflecting at the fixed portion, so metal fatigue increases at the boundary, and there is a risk of cracking and breakage. In particular, in the case of use exceeding the appropriate conveyed material quantity, cracking and breakage occur at the above boundary.

[0005] Patent Document 1 discloses a shaftless screw blade provided with a plurality of protruding portions for mixing in one pitch (p) of the shaftless screw blade body (10), but the protruding portions for mixing are not intended for reinforcing against breakage of the blade.

Prior Art Documents

Patent Documents

[0006] [Patent Document 1] Japanese Patent Publication No. 2023-61502 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] This invention provides a shaftless screw blade and a shaftless screw conveying device that prevent the shaftless screw blade from breaking for a longer period of time than conventional devices. [Means for solving the problem]

[0008] The shaftless screw blade (1) of the present invention is The shaftless screw blade body (10) and A flange (20) is fixed to the base end (10a) of the shaftless screw blade body (10), At least one reinforcing rib (30) that fixes the flange (20) and the shaftless screw blade body (10), The screwless screw blade body (10) is provided with at least one reinforcing member (40) such that one end (40a) is positioned on the tip (10e) side of the screwless screw blade body (10) than the fixing portion (10d) to which the reinforcing rib (30) is fixed.

[0009] With this configuration, at least one reinforcing member (40) is provided on the shaftless screw blade body (10) such that one end (40a) is positioned on the tip (10e) side of the shaftless screw blade body (10) than the fixing portion (10d) to which the reinforcing rib (30) is fixed. As a result, the tip (10e) side of the shaftless screw blade body (10) is reinforced by the reinforcing member (40) more than the fixing portion (10d). This prevents cracks and fractures from occurring on the tip (10e) side of the shaftless screw blade body (10) rather than on the fixed portion (10d). Therefore, it is possible to provide a shaftless screw blade (1) that does not fracture for a longer period of time than conventional models.

[0010] The reinforcing ribs (30) may be provided in pairs or more within one pitch (i.e., within 360°) of the base of the screw blade, with reference to a virtual line connecting the base end (10a) and the rotational center axis of the base of the screw blade. If there is only one, it may be provided within 220° to 300°. The reinforcing member (40) may be provided such that its other end (40b) is located on the side of the base end (10a) of the shaftless screw blade body (10) that is closer to the fixing portion (10d) or the fixing portion (10d).

[0011] In this configuration, the reinforcing member (40) extends to the fixed portion (10d) of the shaftless screw blade body (10).

[0012] The shaftless screw blade (1) is equipped with multiple reinforcing ribs (31, 32), The reinforcing member (40) may be provided to the reinforcing rib (32) located at the furthest tip (10e) of the shaftless screw blade body (10), among the plurality of reinforcing ribs (31, 32).

[0013] The reinforcing member (40) may be provided on a second main surface (10c) different from the first main surface (10b) of the shaftless screw blade body (10) to which the reinforcing rib (30) is fixed.

[0014] The reinforcing member (40) may be provided on the first main surface (10b) of the shaftless screw blade body (10) to which the reinforcing rib (30) is fixed.

[0015] The reinforcing member (40) may be fixed to the reinforcing rib (30).

[0016] The reinforcing member (40) may be provided so as to extend in the radial direction (a1) of the shaftless screw blade base body (10) over 20% or more, preferably 60% or more, and more preferably 100% of the first main surface (10b) or the second main surface (10c) of the shaftless screw blade base body (10). The reinforcing member (40) may be provided so as to extend along the first main surface (10b) or the second main surface (10c) of the shaftless screw blade base body (10) in the direction of the tip (10e) of the shaftless screw blade base body (10).

[0017] The reinforcing member (40) may be provided in a range smaller than 1 pitch, 1 / 2 pitch, 1 / 3 pitch, and smaller than 1 / 4 pitch of the shaftless screw blade base body (10).

[0018] The cross-sectional shape of the reinforcing member (40) may be the same rectangle as the shape of the shaftless screw blade base body (10). The thickness of the reinforcing member (40) may be 0.5 times to 1.5 times the thickness of the shaftless screw blade base body (10).

[0019] Another shaftless screw conveyor (100) of the present invention is the shaftless screw blade (1) described above, a casing (110) that houses the shaftless screw blade (1) therein, a trough (120) disposed on the inner surface of the casing, a drive unit (130) connected to the flange (20) of the shaftless screw blade (1), and includes.

[0020] The trough (120) is, for example, made of reinforced plastic or metal, and preferably made of stainless steel, for example. The trough (120) may be configured to have a first part and a second part along the longitudinal direction. <000009​​​ The driving part (130) is composed of a motor, a transmission gear, a connecting means, a control device, a power source, etc. The driving part (130) preferably rotates the shaftless screw blade (1) at a rotational speed of 3 rpm to 15 rpm, for example. When the motor of the driving part (130) etc. is installed on the upper part of the shaftless screw blade body (10), there is no need to provide a bearing at the lower part like a shafted screw conveyor, so there is no worry about damage to the bearing. Also, even if the motor of the driving part (130) etc. is installed at the lower part, the sealing performance is high (sealed structure), and there is no worry about conveyed objects getting in. The driving part (130) preferably rotates the shaftless screw blade body (10) at a rotational speed of 5 to 17 rpm, more preferably 8 to 15 rpm. Within the above rotational speed range, it is preferable to decrease the rotational speed as the outer diameter (80 mm to 600 mm) of the shaftless screw blade body (10) is larger, and increase the rotational speed as the outer diameter is smaller.

[0022] The total length (L) of the shaftless screw blade body (10) is, for example, 2 m to 10 m. The outer diameter (r1) of the shaftless screw blade body (10) is, for example, 100 mm to 600 mm. The pitch (p) of the shaftless screw blade body (10) is, for example, 75 mm to 600 mm. The inner diameter (r2) of the shaftless screw blade body (10) is, for example, 20 mm to 300 mm. The thickness (t) of the shaftless screw blade body (10) is, for example, 10 mm to 35 mm. The blade width (w or w×2) of the shaftless screw blade body (10) is, for example, 30 mm to 140 mm. The shaftless screw blade body (10) is formed by welding and fixing members of 3 m to 10 m to constitute a continuous screw blade.

[0023] The outer diameter (r1) is the sum of the inner diameter (r2) and twice the blade width (w). Alternatively, (r2 + w × 2 ≈ r1), where r1 is smaller if w is not perpendicular to the radial direction but is inclined. In another embodiment, two blades may be configured as a single blade, with the outer width surface of the second blade (which has a smaller outer diameter) fixed to the inner width surface of the first blade (which has a larger outer diameter).

[0024] The relationship between the outer diameter (r1) of the shaftless screw blade body (10) and the pitch (p) of the shaftless screw blade body (10) is such that the pitch (p) is 0.5 to 1.5 times the outer diameter (r1), with 1.0 times being preferable.

[0025] The shaftless screw blade body (10) may, for example, have a rectangular cross-section. The blade width (w) and blade thickness (t) are set to larger values ​​as the outer diameter (r1) of the screw blade base increases. The total length (L), screw blade outer diameter (r1), pitch (p), blade inner diameter (r2), and blade width (w) are set according to the physical properties of the conveyed material and / or the amount conveyed per unit time (screw rotation speed) and the degree of mixing.

[0026] Examples of steel materials used as raw materials for the shaftless screw blade body (10) include general structural rolled steel (SS330, SS400, SS490, SS540, etc.), cold-rolled steel sheets (SPCC, SPCD, SPCE, SPCF, SPCG, etc.), carbon steel (S25C, S30C, S35C, S45C, S50C, S55C, etc.), hot-rolled or cold-rolled stainless steel sheets (SUS304, SUS316, SUS430, SUS410, etc.), wear-resistant steel sheets (HARDOX® from Sweden Steel, EVERHARD® from JFE Steel, etc.), high-tensile steel sheets (SM570, SMA570W, etc.), and TMCP type high-tensile steel sheets (SM570TMC, SMA570WTMC, etc.).

[0027] As the raw material for the shaftless screw blade body (10), a steel material with higher strength (higher tensile strength) than general structural rolled steel (SS400) is preferred. This is preferable from the viewpoint of wear resistance and durability. In the case of SS400, the total length of the screw blade shrinks by about 10% to 15% compared to the initial value after long-term use (for example, 6 months, 7 hours / day), but stainless steel plates with higher strength (higher tensile strength) than SS400, such as wear-resistant steel plates (HARDOX® from Sweden Steel Corporation, EVERHARD® from JFE Steel Corporation), shrink to an extremely small degree.

[0028] The raw material for the reinforcing material (40) is the same steel material used for the shaftless screw blade body (10).

[0029] [Effects of the invention] By providing reinforcing material near the reinforcing ribs, the shaftless screw blades and shaftless screw conveying device can effectively suppress the fracture of the shaftless screw blades for a longer period than conventional designs. [Brief explanation of the drawing]

[0030] [Figure 1] This diagram shows an overview of the shaftless screw blade according to Embodiment 1. [Figure 2] This is a cross-sectional view taken along line II-II in Figure 1. [Figure 3] This figure shows an overview of the shaftless screw conveying device according to the same embodiment. [Figure 4] This figure illustrates the mounting position of the reinforcing material in the shaftless screw blade according to Embodiment 2 (where there are two reinforcing ribs and the shaftless screw blade base is right-handed). [Figure 5] This diagram illustrates the mounting position of the reinforcing material in the shaftless screw blade according to Embodiment 3 (where there are two reinforcing ribs and the shaftless screw blade base is left-handed). [Modes for carrying out the invention]

[0031] In each drawing, the dimensions of components may be enlarged or reduced from their actual dimensions for the sake of clarity, and the dimensional ratios between drawings may not be consistent. Furthermore, in each drawing, some components may be omitted for the sake of clarity.

[0032] Terms including ordinal numbers such as "1st," "2nd," etc., are used to describe various components, but these terms are used solely for the purpose of distinguishing one component from others, and the components are not particularly limited by these terms. Furthermore, the number of components including ordinal numbers is not particularly limited; for example, there may be only one. Also, the ordinal numbers used in the following specification and drawings may differ from the ordinal numbers described in the claims.

[0033] The following description will explain one embodiment of a shaftless screw blade and shaftless screw conveying device with reference to Figures 1 to 5. Note that the following embodiment is provided as an example to aid in understanding the configuration of the shaftless screw blade and shaftless screw conveying device, and does not limit the configuration of the shaftless screw blade and shaftless screw conveying device.

[0034] (Embodiment 1) The shaftless screw blade 1 of Embodiment 1 will be described with reference to the drawings. As shown in Figure 1, the shaftless screw blade 1 comprises a shaftless screw blade body 10, a flange 20 fixed to the base end 10a of the shaftless screw blade body 10, a reinforcing rib 30 that fixes the flange 20 to the shaftless screw blade body 10, and a reinforcing member 40 provided on the shaftless screw blade body 10.

[0035] In each figure, the first direction D1 is parallel to the rotation axis O1 of the shaftless screw blade 1 (hereinafter, the first direction D1 may be referred to as the rotation axis direction), the second direction D2 and the third direction D3 are perpendicular to the rotation axis direction D1 of the shaftless screw blade 1, and the rotation axis direction D1, the second direction D2 and the third direction D3 are perpendicular to each other.

[0036] The shaftless screw blade body 10 is formed in a spiral shape from the base end 10a to the tip end 10e (see Figure 3). The shaftless screw blade body 10 is formed in a right-handed spiral, for example, as in this embodiment. However, the shaftless screw blade body 10 may also be formed in a left-handed spiral.

[0037] The shaftless screw blade 1 includes, for example, a reinforcing member 40, as in this embodiment. The reinforcing member 40 has a thickness of 0.5 to 1.5 times the thickness t of the shaftless screw blade body 10, so as to increase the thickness t of the shaftless screw blade body 10. Although not particularly limited, in this embodiment, the reinforcing member 40 has the same thickness t as the thickness t of the shaftless screw blade body 10.

[0038] The reinforcing member 40 is fixed to a second main surface 10c of the shaftless screw blade body 10, which is different from the first main surface 10b to which the reinforcing rib 30 is fixed, as in this embodiment. Although not particularly limited, in this embodiment the reinforcing member 40 is welded to the shaftless screw blade body 10. The reinforcing member 40 may also be mechanically fixed to the shaftless screw blade body 10, for example, by using bolts and nuts. Alternatively, the reinforcing member 40 may be fixed to the shaftless screw blade body 10 with adhesive.

[0039] As shown in Figures 1 and 2, the reinforcing member 40 is positioned such that, for example, as in this embodiment, one end 40a of the reinforcing member 40 is located on the tip 10e side of the shaftless screw blade body 10, rather than on the fixing portion 10d to which the reinforcing rib 30 is fixed.

[0040] Furthermore, the reinforcing member 40 is provided such that its other end 40b is located on the fixed portion 10d, as in this embodiment. More specifically, the other end 40b is provided so as to overlap with the fixed portion 10d when viewed in the first direction D1. In this way, the other end 40b of the reinforcing member 40 is positioned to contact at least a portion of the fixed portion 10d. Although not particularly limited, in this embodiment, the other end 40b of the reinforcing member 40 is positioned to contact half of the fixed portion 10d, specifically the area R1 on the tip 10e side of the shaftless screw blade body 10.

[0041] The reinforcing member 40 is positioned such that one end 40a and the other end 40b are parallel to the radial direction a1 of the shaftless screw blade body 10, as in this embodiment. However, at least one of the two ends 40a and 40b of the reinforcing member 40 may be positioned so as not parallel to the radial direction a1 of the shaftless screw blade body 10.

[0042] The reinforcing member 40 is provided, for example, in the radial direction a1 of the shaftless screw blade body 10, so as to extend over the entire (100%) second main surface 10c of the shaftless screw blade body 10. Alternatively, the reinforcing member 40 is provided, for example, in the direction of the tip 10e of the shaftless screw blade body 10, so as to extend along the second main surface 10c of the shaftless screw blade body 10 (so as to form a part of the helical shape).

[0043] In one embodiment, the reinforcing member 40 may be provided so as to extend over 20% or more, preferably 60% or more, of the second main surface 10c in the radial direction a1 of the shaftless screw blade body 10.

[0044] Furthermore, the reinforcing member 40 may be provided on the first main surface 10b. The reinforcing member 40 may also be provided on both the first main surface 10b and the second main surface (10c).

[0045] Furthermore, the reinforcing member 40 is provided in a range smaller than 1 / 4 pitch of the shaftless screw blade body 10, for example, as in this embodiment. Although not particularly limited, in this embodiment, the reinforcing member 40 is provided such that the angle α formed by the line segment S1 connecting one end 40a and the rotation axis O1 and the line segment S2 connecting the other end 40b and the rotation axis O1 is 60°. Note that the angle α may be between 30° and 90°.

[0046] According to this embodiment, the reinforcing member 40 is provided so as to extend from the fixed portion 10d toward the tip 10e side of the shaftless screw blade body 10. As a result, in the part of the shaftless screw blade body 10 where bending is less likely to occur due to the fixing of the reinforcing rib 30, the strength of that part is increased by fixing the reinforcing member 40, making it less susceptible to metal fatigue and protecting it from cracks and fractures.

[0047] The greater the thickness of the reinforcing material 40, or the greater the angle α, the more likely it is that the conveying by the shaftless screw blade 1 and the rotation of the shaftless screw blade body 10 will be hindered. Therefore, the thickness and angle α of the reinforcing material 40 are designed to be appropriate values ​​(in this embodiment, the thickness is the thickness t of the shaftless screw blade body 10, and α is 60°) so as not to hinder the conveying by the shaftless screw blade 1 and the rotation of the shaftless screw blade body 10, and to protect the shaftless screw blade body 10 from cracks and fractures.

[0048] As shown in Figure 3, the shaftless screw conveying device 100 comprises a shaftless screw blade 1, a casing 110 that houses the shaftless screw blade 1 inside, a trough 120 positioned on the inner surface of the casing 110, and a drive unit 130 connected to the flange 20 of the shaftless screw blade 1.

[0049] The drive unit 130 consists of a motor, a speed change gear, a coupling means, a control device, a power supply, and the like. The drive unit 130 rotates the shaftless screw blade 1 at a rotational speed of, for example, 5 rpm to 12 rpm. The drive shaft 131 passes through the casing 110 with a seal unit (not shown) installed in between, improving the airtightness between the drive shaft 131 and the casing 110. The casing 110 includes an input section for the material to be conveyed (not shown) and a discharge section for discharging the mixed material to be conveyed.

[0050] In this embodiment, The total length (L) of the shaftless screw blade body 10 is, for example, 5m to 10m. The outer diameter (r1) of the shaftless screw blade body 10 is, for example, 300mm to 400mm. The pitch (p) of the shaftless screw blade body 10 is, for example, 400 mm to 500 mm. The inner diameter (r2) of the shaftless screw blade body 10 is, for example, 20 mm to 300 mm. The thickness (t) of the shaftless screw blade body 10 is, for example, 25 mm. The blade width (w) of the shaftless screw blade body 10 is, for example, 30 mm to 140 mm.

[0051] (Embodiment 2) The following description of Embodiment 2 will focus on the differences between it and Embodiment 1. Components identical to those in Embodiment 1 will be denoted by the same reference numerals, and their descriptions will be omitted.

[0052] The shaftless screw blade 1a of Embodiment 2 comprises a right-handed shaftless screw blade body 10, a first reinforcing rib 31, and a second reinforcing rib 32 located on the tip 10e side of the shaftless screw blade body 10, relative to the first reinforcing rib 31. Although not particularly limited, in this embodiment, as shown in Figure 4, the first reinforcing rib 31, the second reinforcing rib 32, and the base end 10a of the shaftless screw blade body 10 are arranged at a 120° interval around the rotation axis O1 in a view along the rotation axis D1.

[0053] In this embodiment, the second fixing portion 10g to which the second reinforcing rib 32 is fixed is located on the tip 10e side of the shaftless screw blade body 10 than the first fixing portion 10f to which the first reinforcing rib 31 is fixed. In this embodiment, the reinforcing member 40 is provided on the shaftless screw blade body 10 such that one end 40a is located on the tip 10e side of the shaftless screw blade body 10 than the second fixing portion 10g.

[0054] Thus, the reinforcing member 40 is provided to the second reinforcing rib 32, which is located on the tip 40e side of the shaftless screw blade body 10, out of the first reinforcing rib 31 and the second reinforcing rib 32.

[0055] Furthermore, the reinforcing member 40 is provided such that its other end 40b is located on the second fixing portion 10g, as in this embodiment. More specifically, the other end 40b is provided so as to overlap with the second fixing portion 10g when viewed in the first direction D1. In this way, the other end 40b of the reinforcing member 40 is positioned to contact at least a portion of the second fixing portion 10g. Although not particularly limited, in this embodiment, the other end 40b of the reinforcing member 40 is positioned to contact half of the region R2 on the tip 10e side of the shaftless screw blade body 10 of the second fixing portion 10g. The shape and size of the reinforcing member 40 are the same as in Embodiment 1.

[0056] In the shaftless screw blade 1a of Embodiment 2, a reinforcing material 40 is provided from the second fixing portion 10g, which has a greater difference in flexibility between the fixing portions 10f, 10g and the tip 10e side of the shaftless screw blade body 10 than the fixing portions 10f, 10g, toward the tip 10e side of the shaftless screw blade body 10. This protects the parts of the shaftless screw blade body 10 that are prone to cracking or fracture from cracking or fracture.

[0057] (Embodiment 3) The following description of Embodiment 3 will focus on the differences between it and Embodiment 2. Components identical to those in Embodiment 2 will be denoted by the same reference numerals, and their descriptions will be omitted.

[0058] The shaftless screw blade 1b of Embodiment 3 comprises a left-handed shaftless screw blade body 10, a first reinforcing rib 31, and a second reinforcing rib 32 located on the tip 10e side of the shaftless screw blade body 10, relative to the first reinforcing rib 31. Although not particularly limited, in this embodiment, the first reinforcing rib 31, the second reinforcing rib 32, and the base end 10a of the shaftless screw blade body 10 are arranged at a 120° interval with respect to the rotation axis O1 in a view along the rotation axis D1, as shown in Figure 5.

[0059] In this embodiment, the reinforcing member 40 is provided on the shaftless screw blade body 10 such that one end 40a is located on the tip 10e side of the shaftless screw blade body 10, rather than on the second fixing portion 10g. Thus, the reinforcing member 40 is provided on the second reinforcing rib 32, which is located on the tip 40e side of the shaftless screw blade body 10, out of the first reinforcing rib 31 and the second reinforcing rib 32. In this embodiment, the reinforcing member 40 is provided such that, for example, the other end 40b is located on the second fixing portion 10g. More specifically, the other end 40b is provided so as to overlap with the second fixing portion 10g when viewed in the first direction D1. In this way, the other end 40b of the reinforcing member 40 is positioned so as to contact at least a part of the second fixing portion 10g. The shape and size of the reinforcing member 40 are the same as in Embodiment 1 and Embodiment 2.

[0060] In the shaftless screw blade 1b of Embodiment 3, a reinforcing member 40 is provided from the second fixing portion 10g, which has a greater difference in flexibility between the fixing portions 10f, 10g and the tip 10e side of the shaftless screw blade body 10 than the fixing portions 10f, 10g, toward the tip 10e side of the shaftless screw blade body 10. This protects the parts of the shaftless screw blade body 10 that are prone to cracking or fracture from cracking or fracture.

[0061] (Another embodiment) (1) In the shaftless screw blades 1, 1a, 1b according to the above embodiment, the reinforcing member 40 is provided such that its other end 40b is located on the fixed portions 10d, 10g. However, the shaftless screw blades 1, 1a, 1b are not limited to this configuration.

[0062] For example, the reinforcing member 40 may be configured such that its other end 40b is positioned on the base end 10a side of the shaftless screw blade body 10, rather than on the fixing parts 10d and 10g. Alternatively, the reinforcing member 40 may be configured such that its other end 40b is positioned on the tip end 10e side of the shaftless screw blade body 10, rather than on the tip end 10e side of the shaftless screw blade body 10, rather than on the fixing parts 10d and 10g. Alternatively, the reinforcing member 40 may be configured such that its other end 40b is positioned on the base end 10a side of the shaftless screw blade body 10, rather than on the base end 10a side of the shaftless screw blade body 10, rather than on the tip end 10e side of the shaftless screw blade body 10, rather than on the fixing parts 10d and 10g (a position where the reinforcing member 40 does not come into contact with the fixing parts 10d and 10g).

[0063] (2) In the shaftless screw blades 1a and 1b according to the above embodiment, the reinforcing member 40 is configured such that one end 40a is located on the tip 10e side of the shaftless screw blade body 10, which is closer to the second fixing portion 10g, and the other end 40b is located on the second fixing portion 10g. However, the shaftless screw blades 1a and 1b are not limited to this configuration.

[0064] For example, the reinforcing member 40 may be configured such that one end 40a is positioned on the base end 10a side of the shaftless screw blade body 10 than the second fixing portion 10g, and the other end 40b is positioned on the base end 10a side of the shaftless screw blade body 10 than the one end 40a. In this case, the other end 40b of the reinforcing member 40 may be positioned in a position that contacts at least a part of the first fixing portion 10f, or the other end 40b may be positioned on the tip 10e side of the shaftless screw blade body 10 than the first fixing portion 10f (a position where the reinforcing member 40 does not contact the first fixing portion 10f).

[0065] (3) In the shaftless screw blades 1, 1a, and 1b according to the above embodiment, the reinforcing member 40 is a single continuous member, but for example, the reinforcing member 40 may be composed of multiple members. For example, the reinforcing member 40 may be divided into multiple members in the circumferential direction (the rotation direction of the shaftless screw blade body 10).

[0066] <Examples> Total length (L) of shaftless screw blade body 10: 7500m Outer diameter (r1) of shaftless screw blade body 10: 390 mm Pitch (p) of shaftless screw blade body 10: 410 mm Inner diameter (r2) of shaftless screw blade body 10: 250 mm Thickness (t) of shaftless screw blade body 10: 25 mm Blade width (w) of shaftless screw blade body 10: 70 mm The shaftless screw blade body 10 described above was equipped with a reinforcing material 40 as in Embodiment 1, and general waste was transported as the material to be transported. No cracks or fractures occurred in the shaftless screw blade body 10 for at least 6 months.

[0067] <Comparative Example> A screw-less blade body 10, similar to that in the example, was used to transport general waste as the material being transported, without the reinforcing material 40. After one month, it was confirmed that cracks and fractures had occurred in the screw-less blade body 10. [Explanation of Symbols]

[0068] 1...Shaftless screw blade, 1a...Shaftless screw blade, 1b...Shaftless screw blade, 10...Shaftless screw blade body, 10a...Base end, 10b...First main surface, 10c...Second main surface, 10d...Fixing part, 10e...Tip, 10f...First fixing part, 10g...Second fixing part, 20...Flange, 30...Reinforcement rib, 31...First reinforcement rib, 32...Second reinforcement rib, 40...Reinforcement material, 40a...One end, 40b...Other end, 100...Shaftless screw conveying device, 110...Casing, 120...Trough, 130...Drive means, O1...Rotation shaft, a1...Radial direction

Claims

1. The shaftless screw blade body and A flange fixed to the base end of the shaftless screw blade base, At least one reinforcing rib that fixes the flange and the shaftless screw blade body, At least one reinforcing member is provided on the base of the shaftless screw blade so that one end of the shaftless screw blade body is positioned on the tip side of the base of the shaftless screw blade, rather than on the fixing portion to which the reinforcing rib is fixed. A shaftless screw blade equipped with this feature.

2. The shaftless screw blade according to claim 1, wherein the reinforcing member is provided such that its other end is located on the base end side of the shaftless screw blade base body, or on the base end side of the fixing portion.

3. Equipped with multiple reinforcing ribs, The shaftless screw blade according to claim 1 or 2, wherein the reinforcing material is provided to the reinforcing rib located at the furthest tip end of the shaftless screw blade base, among the plurality of reinforcing ribs.

4. A shaftless screw blade according to claim 1 or 2, A casing that houses the aforementioned shaftless screw blades inside, A trough is disposed on the inner surface of the casing, A drive unit connected to the flange of the aforementioned shaftless screw blade, A shaftless screw conveying device equipped with the following features.

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