Fluid conveyor

Abstract

To provide a fluid conveyor that exhibits high conveying efficiency. [Solution] The fluid conveyor 20 has a casing 21 and spiral blades 22. The spiral blades 22 are fixed to the inner circumferential surface 31 of the casing 21 and protrude inward. The spiral blades 22 are formed by curving a flat bar in a spiral shape and extend in the axial direction 7 at a predetermined pitch 121. The protruding width 123 of the spiral blades 22 is less than half the inner diameter of the casing 21. A central flow path 34 is formed in the center of the casing 21 along the central axis 6. The fluid conveyor 20 is rotatably supported by a support mechanism and rotationally driven by a drive device.

Description

Technical Field

[0004] , , , ,

[0006] , , , , , , , , , , , ,

[0005] , ,

[0001] This invention relates to a device for transporting fluids, and more particularly, to the structure of a fluid transporter used in this device.

Background Art

[0002] Devices for transporting powders, granules, etc., as well as devices for transporting liquids and gases to generate thrust, have been conventionally provided.

[0003] Patent Document 1 discloses a powder transport device for transporting flour, skim milk powder, toner, and other powders. The powder transport device disclosed in this document includes a cylindrical body, a rotating shaft disposed at the center of this cylindrical body, spiral blades extending from this rotating shaft, and a motor. The motor rotates the spiral blades via the rotating shaft, and the rotated spiral blades transport the powder.

[0004] Patent Document 2 discloses a liquid transport device used as a ship's side thruster device. The side thruster device (liquid transport device) disclosed in this document includes a motor disposed inside a through-hole penetrating the ship's bottom in the left-right direction, and a propeller attached to the drive shaft of this motor. The propeller rotated by the motor transports a liquid such as seawater to generate a propulsive force.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0007] Therefore, the object of the present invention is to provide a fluid conveyor that can improve the efficiency of fluid transport. [Means for solving the problem]

[0008] (1) The fluid conveyor according to the present invention comprises a cylindrical casing into which fluid is supplied, and spiral blades protruding from the inner circumferential surface of the casing and extending spirally along the central axis of the casing at a predetermined pitch.

[0009] When the casing rotates around its central axis, the spiral blades rotate along with the casing. Because the spiral blades extend spirally along the central axis, the rotating blades can move (convey) the fluid supplied to the casing from one direction to the other along the central axis. Since these spiral blades protrude from the inner circumferential surface of the casing, they do not have a rotation axis like conventional blades. Therefore, fluid conveyance is not hindered by a rotation axis, and the flow path volume within the casing is larger compared to conventional fluid conveying devices. As a result, the fluid conveyance efficiency is improved.

[0010] (2) The fluid conveyor according to the present invention comprises a cylindrical casing into which fluid is supplied, and N (where N is a plurality) protruding blades that protrude from the inner circumferential surface of the casing and are arranged at equal intervals around the central axis of the casing. The protruding blades are inclined with respect to the direction of the central axis and the radial direction of the casing in order to convey the fluid by rotating around the central axis.

[0011] When the casing rotates around its central axis, the protruding vanes rotate along with the casing. Since the protruding vanes are inclined with respect to the direction of the central axis and the radial direction, the rotating vanes can move (convey) the fluid supplied to the casing from one direction to the other along the central axis. Because these protruding vanes are projected from the inner circumferential surface of the casing, they do not have a rotation axis like conventional vanes. Therefore, fluid conveyance is not hindered by a rotation axis, and the flow path volume within the casing is larger compared to conventional fluid conveying devices. As a result, the fluid conveyance efficiency is improved.

[0012] (3) The N protruding blades may be arranged along N virtual helices that extend in the direction of the central axis at a predetermined pitch (P) and are displaced by P / N along the central axis.

[0013] In this configuration, the relative positions of the N protruding blades are the same as the relative positions of the multiple threads in a so-called multi-start screw (N-start screw). The N protruding blades formed in this way can efficiently transport fluid.

[0014] (4) The above-mentioned protruding blades may be in the form of three.

[0015] (5) The width of the spiral blade protruding radially from the casing may be less than half of the inner diameter of the casing.

[0016] In this configuration, a central flow channel is formed around the central axis of the casing, where spiral vanes are absent. As a result, the fluid is smoothly transported through this central flow channel. Therefore, even if the fluid contains particles with relatively large outer diameters, malfunctions due to clogging by these particles are suppressed.

[0017] (6) The length of the protruding vane in the radial direction of the casing may be less than half of the inner diameter of the casing.

[0018] In this configuration, a central flow path is formed around the central axis of the casing, without any protruding vanes. As a result, the fluid is smoothly transported through this central flow path. Therefore, even if the fluid contains particles with a relatively large outer diameter, malfunctions due to clogging by the particles are suppressed.

[0019] (7) The fluid conveyor according to the present invention is used in a fluid conveying device. The fluid conveying device comprises a cylindrical casing to which fluid is supplied; spiral blades protruding from the inner circumferential surface of the casing and extending spirally along the central axis of the casing at a predetermined pitch; a support that rotatably supports the casing about the central axis; and a drive device disposed outside the casing and rotating the casing.

[0020] In a fluid conveying device, a drive unit rotates the casing. Since the casing is supported by a support, it rotates smoothly. The spiral blades rotate together with the casing. The rotating spiral blades can move (convey) the fluid supplied to the casing from one direction to the other along the central axis. Since these spiral blades protrude from the inner circumferential surface of the casing, they do not have a rotation axis like conventional blades. Therefore, fluid conveyance is not hindered by a rotation axis, and the flow path volume within the casing is larger compared to conventional fluid conveying devices. As a result, the fluid conveying efficiency is improved.

[0021] (8) The fluid conveyor according to the present invention is used in a fluid conveying device. The fluid conveying device comprises a cylindrical casing to which fluid is supplied, N (where N is a plurality) protruding blades projecting from the inner circumferential surface of the casing and arranged at equal intervals around the central axis of the casing, a support that rotatably supports the casing around the central axis, and a drive device disposed outside the casing to rotate the casing. The protruding blades are inclined with respect to the direction of the central axis and the radial direction of the casing in order to convey the fluid by rotating around the central axis.

[0022] In a fluid conveyance device, a driving device rotates a casing. Since the casing is supported by a support, it rotates smoothly. The protruding blades rotate together with the casing. The rotating protruding blades can move (convey) the fluid supplied to the casing from one direction to the other in the direction of the central axis. Since this protruding blade protrudes from the inner peripheral surface of the casing, it does not have a rotating shaft like a conventional blade. Therefore, the conveyance of the fluid is not hindered by the rotating shaft, and the flow path volume in the casing becomes larger than that of a conventional fluid conveyance device. As a result, the fluid conveyance efficiency is improved.

[0023] (9) The N protruding blades may be arranged along N virtual helices that extend in the direction of the central axis at a predetermined pitch (P) and are displaced by P / N along the central axis, respectively.

[0024] In this configuration, the relative positions of the N protruding blades have the same positional relationship as the relative positions of a plurality of thread ridges in a so-called multi-start screw (N-start screw). The N protruding blades formed in this way can efficiently convey the fluid.

[0025] (10) The driving device may include a plurality of magnetic bodies arranged along the circumferential direction on the outer peripheral surface of the casing, a plurality of exciting coils arranged along the circumferential direction on the radially outer side of the casing than the magnetic bodies, and a driving circuit that generates a rotating magnetic field in the exciting coils.

[0026] In this configuration, the rotating magnetic field generated by the exciting coil gives a rotational torque by magnetic force to the casing to which the magnetic body is attached. Thereby, the casing rotates without contact, so the durability of the fluid conveyance device is improved. <000s096>

Advantages of the Invention

[0027] According to the present invention, the fluid conveyance efficiency is improved.

Brief Description of the Drawings

[0028] [Figure 1] Figure 1 is a cross-sectional view of a fluid conveying device 10 equipped with a fluid conveyor 20 according to an embodiment of the present invention. [Figure 2] Figure 2 is a cross-sectional view of a fluid conveyor 20 according to an embodiment of the present invention. [Figure 3] Figure 3 is a view taken along arrow III in Figure 2. [Figure 4] Figure 4 is a perspective view of the main parts of the fluid conveyor 20. [Figure 5] Figure 5 is a cross-sectional view of the VV section in Figure 1. [Figure 6] Figure 6 is a cross-sectional view taken along the line VI-VI in Figure 1. [Figure 7] Figure 7 is a schematic circuit diagram of the fluid transport device 10. [Figure 8] Figure 8 is a cross-sectional view taken along line VIII-VIII in Figure 1. [Figure 9] Figure 9 is a perspective view of the main part of a fluid conveyor 70 according to a modified example 1 of the present invention. [Figure 10] Figure 10 is a view taken along the line X in Figure 9. [Figure 11] Figure 11 is a cross-sectional view of the fluid conveyor 70. [Figure 12] Figure 12 illustrates the positional relationships between the protruding blades 71, 72, and 73, and the virtual helices 74, 75, and 76. [Figure 13] Figure 13 is a cross-sectional view of a fluid conveying device 80 according to a modified example 2, which includes a fluid conveyor 20 according to an embodiment of the present invention. [Figure 14] Figure 14 is a cross-sectional view of a fluid conveying device 90 according to a modified example 3, which includes a fluid conveying device 20 according to an embodiment of the present invention. [Figure 15] Figure 15 is a cross-sectional view of a fluid conveying device 100 according to a modified example 4, which includes a fluid conveying device 20 according to an embodiment of the present invention. [Modes for carrying out the invention]

[0029] Preferred embodiments of the present invention will be described below with reference to the drawings as appropriate. It goes without saying that these embodiments represent only one aspect of the fluid conveyor and fluid conveying device according to the present invention, and the embodiments may be modified without altering the essence of the present invention.

[0030] [Fluid conveying device 10]

[0031] Figure 1 is a cross-sectional view of a fluid conveying device 10 equipped with a fluid conveyor 20 according to an embodiment of the present invention.

[0032] The fluid conveying device 10 is positioned between two pipes 11 through which the fluid is supplied. In this embodiment, the fluid is a concept that includes liquids, gases, powders, and granules. Liquids include water, crude oil, petroleum products, and alcohol. Petroleum products include heavy oil, light oil, gasoline, benzene, and toluene. Gases include natural gas, fuel gas, air, and noble gases. Powders include grain flour, skim milk powder, toner, etc. Granules include grains, resin pellets, crushed ore, etc. Grains include corn, rice, beans, etc. The fluid conveying device 10 is used, for example, for transporting crude oil, natural gas, and grains, transporting fuel gas within cities, and transporting water, alcohol, benzene, and noble gases within factories. Furthermore, it is used as a propulsion system for ships and as an air conditioning system for buildings.

[0033] When the fluid conveying device 10 is in operation, the fluid in the pipe 11 is conveyed along the axial direction 7 in the manner described later. A distinctive feature of the fluid conveying device 10 is the structure of the fluid conveyor 20, which will be described in detail later. The fluid conveying efficiency is improved by the structure of the fluid conveyor 20, which will be described later.

[0034] As shown in Figure 1, the fluid conveying device 10 includes a fluid conveyor 20, a support mechanism 40 that supports the fluid conveyor 20, a drive device 50 that rotates the fluid conveyor 20, and a joint 60 that connects the fluid conveyor 20 to the pipe 11.

[0035] [Fluid conveyor 20]

[0036] Figure 2 is a cross-sectional view of a fluid conveyor 20 according to an embodiment of the present invention. Figure 3 is a view taken along arrow III in Figure 2. Figure 4 is a perspective view of a partially cutaway main part of the fluid conveyor 20.

[0037] As shown in Figure 2, the fluid conveyor 20 has a casing 21 and spiral blades 22. In Figures 1 and 2, the spiral blades 22 are shown as a side view rather than a cross-sectional view. In these figures, the shaded area 33 is the connection point (welded portion) between the spiral blades 22 and the inner circumferential surface 31 of the casing 21.

[0038] The casing 21 is a cylindrical member having an inner circumferential surface 31 and an outer circumferential surface 32. In the figure, the dashed line 6 indicates the central axis of the casing 21. The direction of this central axis 6 coincides with the axial direction 7. The casing 21 is made of ferrous metals such as stainless steel or non-ferrous metals such as aluminum alloy. However, in this embodiment, the casing 21 is made of a commercially available stainless steel pipe as a standard product. The material of the casing 21 is not particularly limited and is appropriately determined according to the properties of the fluid being conveyed.

[0039] The inner diameter 111 and wall thickness 117 of the casing 21 are determined according to the type of fluid to be conveyed and the required conveying volume. The outer diameter 112 of the casing 21 is determined by the inner diameter 111 and the wall thickness 117 of the casing 21.

[0040] The spiral blade 22 is fixed to the inner circumferential surface 31 of the casing 21 and protrudes inward from the inner circumferential surface 31. In this embodiment, the material constituting the spiral blade 22 is the same as that of the casing 21, and consists of iron materials such as stainless steel, and non-ferrous metals such as aluminum alloy. The spiral blade 22 is made of, for example, a rectangular flat bar. In this embodiment, the spiral blade 22 is formed by bending this flat bar into a spiral shape by press working. The above-mentioned region 33 of the spiral blade 22 is welded to the inner circumferential surface 31 of the casing 21, and the spiral blade 22 is integrally formed with the casing 21.

[0041] As shown in Figures 2 to 4, the spiral blade 22 extends spirally along the axial direction 7 of the casing 21. As shown in Figure 2, the spiral shape of the spiral blade 22 is defined by the helix angle α. In this embodiment, the helix angle α represents the inclination of the spiral with respect to the virtual cross-section 12 of the casing 21 (the plane perpendicular to the central axis 6). The helix angle α determines the pitch 121 of the spiral blade 22. The pitch 121 is the length of one full turn of the spiral in the axial direction 7. The spiral shape of the spiral blade 22 may also be defined by this pitch 121. The wall thickness 26, total length 118, and helix angle α of the spiral blade 22 are determined according to the type of fluid being conveyed and the required conveying amount.

[0042] The height of the spiral vane 22, i.e., the projection width 123 of the spiral vane 22 in the radial direction 8, is less than half of the inner diameter 111 (less than the radius of curvature of the inner circumferential surface 31) in any portion along the axial direction 7. This forms a central channel 34 around the central axis 6. In Figures 2 and 4, the central channel 34 is shown by a dashed line. The central channel 34 is formed by the inner edge 25 of the spiral vane 22 and extends along the axial direction 7.

[0043] The protrusion width 123 is not particularly limited, but is determined appropriately depending on the properties of the fluid. In this embodiment, the protrusion width 123 is determined such that the diameter 113 of the central channel 34 is larger than the maximum diameter of the granular material being conveyed. This prevents the fluid from clogging inside the casing 21, even if the conveyed fluid is in the form of granular material.

[0044] [Support mechanism 40]

[0045] Figure 5 is a VV cross-sectional view in Figure 1, showing the structure of the support mechanism 40.

[0046] As shown in Figures 1 and 5, the support mechanism 40 comprises a frame 41 and a plurality of rolling elements 42 supported by the frame 41. The plurality of rolling elements 42 function as supports for the fluid conveyor 20.

[0047] In this embodiment, the frame 41 is made of a rectangular tubular member. The frame 41 houses the fluid conveyor 20 and surrounds the casing 21 in the circumferential direction 9. The frame 41 is fixed to a building such as a factory or the hull of a ship via brackets or the like (not shown). The frame 41 may have other shapes, such as a cylindrical shape, as long as it can surround the casing 21 in the circumferential direction 9.

[0048] As shown in Figure 1, multiple rolling elements 42 are arranged at one end and the other end of the casing 21 in the axial direction 7. In this embodiment, four rolling elements 42 are arranged around one end of the casing 21, and similarly, four rolling elements 42 are arranged around the other end of the casing 21. Although each end is supported by four rolling elements 42, the number of rolling elements 42 supporting each end is not particularly limited and can be three or more. As shown in Figure 5, in this embodiment, each rolling element 42 is arranged evenly (at 90-degree intervals) in the circumferential direction 9.

[0049] In this embodiment, the rolling element 42 is a disc member having a predetermined thickness and is supported by a support shaft 44. This support shaft 44 is arranged along the central axis 6. A through hole 43 is provided in the center of the rolling element 42, and the support shaft 44 is inserted through this through hole 43. The rolling element 42 is rotatable around the support shaft 44. In this embodiment, both ends of the support shaft 44 are supported by fixing members 45, and the support shaft 44 is fixed to the frame 41 via the fixing members 45.

[0050] The circumferential surface of each rolling element 42 is in contact with the outer circumferential surface 32 of the casing 21, thereby allowing the fluid conveyor 20 to rotate smoothly around the central axis 6. Since the casing 21 is in rolling contact with the rolling elements 42, the resistance to the rotation of the casing 21 is reduced. This, in turn, improves the durability of the fluid conveyor 20 and the fluid conveying device 10. Note that the rolling elements 42 do not need to be disc members; they may be rollers or spheres. In short, the rolling elements 42 only need to be in rolling contact with the casing 21.

[0051] [Drive unit 50]

[0052] Figure 6 is a cross-sectional view of the VI-VI section in Figure 1, showing the structure of the drive unit 50. Figure 7 is a schematic circuit diagram of the fluid transport device 10.

[0053] The drive unit 50 comprises a mounting member 23 and a plurality of magnetic bodies 24 shown in Figures 2 and 1, a holding member 52, a stator core 59, and a plurality of excitation coils 51 shown in Figures 1 and 6, and a drive circuit 53 shown in Figure 7. The mounting member 23 and the plurality of magnetic bodies 24 are provided on the casing 21 of the fluid transporter 20, as shown in Figure 2. The holding member 52 and the stator core 59 are provided on the frame 41 of the support mechanism 40, as shown in Figure 1.

[0054] As shown in Figures 2 and 3, the mounting member 23 is a hollow ring-shaped member attached to the outer circumferential surface 32 of the casing 21. In this embodiment, the mounting member 23 is fixed to the casing 21 via adhesive or other known fasteners. The mounting member 23 is located in the central part of the casing 21 in the axial direction 7, i.e., at or near the center of gravity of the casing 21. The multiple magnetic bodies 24 are housed and fixed inside the mounting member 23. In other words, the magnetic bodies 24 are fixed to the casing 21.

[0055] The magnetic material 24 is typically a permanent magnet, but may also be a magnetized metal. As shown in Figures 3 and 6, the multiple magnetic materials 24 are evenly arranged along the circumferential direction 9. In this embodiment, as shown in Figure 3, four magnetic materials 24 are arranged at 90-degree intervals along the circumferential direction 9. Note that the number of magnetic materials 24 is not limited to four; two or more are acceptable.

[0056] The stator core 59 according to this embodiment (see Figures 1 and 6) has a known structure and comprises a ring-shaped portion and a plurality of teeth protruding from this ring-shaped portion. Conductors are wound around these teeth to form an excitation coil 51.

[0057] As shown in Figure 6, the multiple excitation coils 51 are arranged radially outward from the magnetic material 24 on the casing 21. In this embodiment, three excitation coils 51 are formed, and they are arranged evenly along the circumferential direction 9 (at 120-degree intervals). Note that the number of excitation coils 51 is not limited to three; two or more are acceptable.

[0058] The retaining member 52 is a hollow, ring-shaped member that is fixed to the frame 41 via known fastening means. In this embodiment, the retaining member 52 is made of resin and is insulating. In other words, the retaining member 52 is a so-called insulator, and the stator core 59 and excitation coil 51 are housed within the retaining member 52.

[0059] In this embodiment, the inner diameter 114 of the retaining member 52 is slightly larger than the outer diameter 115 of the mounting member 23, and the retaining member 52 does not come into contact with the mounting member 23. Therefore, even if the casing 21 rotates around the central axis 6, the retaining member 52 or the excitation coil 51 does not obstruct the rotation of the casing 21.

[0060] As shown in Figure 7, the retaining member 52 has a connector 54. The connector 54 is electrically connected to the excitation coil 51 by lead wires 55. One end of a cable 56 is connected to the connector 54.

[0061] The drive circuit 53 is realized by a printed circuit board 57 (see Figure 6) and various electronic components (not shown) mounted on the printed circuit board 57.

[0062] As shown in Figure 6, the printed circuit board 57 is attached to the frame 41 via screws or the like. In this embodiment, the printed circuit board 57 is attached to the outer surface of the frame 41. However, the mounting position of the printed circuit board 57 may be on the inner surface of the frame 41.

[0063] Various electronic components include connector 58 (see Figure 7), resistors, capacitors, diodes, coils, and ICs. The other end of cable 56 is connected to connector 58, and the printed circuit board 57 is electrically connected to the excitation coil 51 through cable 56.

[0064] The IC used is, for example, a commercially available driver IC for a three-phase AC motor. The drive circuit 53 (driver IC) converts power supplied from a power source (not shown) into three-phase AC power and supplies it to the excitation coil 51. The excitation coil 51, supplied with three-phase AC power, forms a rotating magnetic field around the casing 21. Since a magnetic material 24 is provided on the casing 21, the magnetic force generated by the formed rotating magnetic field and the magnetic material 24 rotates the casing 21 around the central axis 6. The printed circuit board 57, on which various electronic components are mounted, functions as a control circuit, while the excitation coil 51 functions as a so-called load.

[0065] The power supply may be an external power supply provided to the fluid conveying device 10 from a facility such as a factory, or it may be an internal power supply such as a battery installed in the fluid conveying device 10.

[0066] [Joint 60]

[0067] Figure 8 is a cross-sectional view of joint 60, shown at line VIII-VIII in Figure 1.

[0068] The joint 60 is a so-called swivel joint, and in this embodiment, a standard (commercially available) product is used. As shown in the figure, the joint 60 connects the fixed pipe 11 to the casing 21 which rotates relative to the pipe 11. The joint 60 is attached to both ends of the casing 21 in the axial direction 7. The joint 60 is fixed to the frame 41 in a manner described later, and together with the support mechanism 40, it rotatably supports the casing 21.

[0069] The joint 60 comprises an outer cylinder 61, an inner cylinder 62 (see Figure 1), a sealing member 63, and a filter 68 (see Figure 1). As shown in Figure 1, the sealing member 63 has a flange 65 and a number of projections 64, which in this embodiment are integrally formed. The projections 64 abut against the outer circumferential surface 32 of the casing 21. Each projection 64 is aligned along the axial direction 7. The sealing member 63 is fixed by the flange 65 being sandwiched between the outer cylinder 61 and the inner cylinder 62.

[0070] The outer cylinder 61 is fixed to the frame 41 via screws or other known fastening means. The outer cylinder 61 and the inner cylinder 62 have a first connection port 66 and a second connection port 67 located on the opposite side. The casing 21 is inserted into the first connection port 66, and the pipe 11 is inserted into the second connection port 67, with the casing 21 facing the pipe 11 and the filter 68 in between. A sealing member may also be provided on the side of the second connection port 67.

[0071] The filter 68 typically has a mesh structure. The filter 68 prevents foreign matter and other particles from entering the casing 21. The filter 68 may be installed only on the side where the fluid flows into the casing 21.

[0072] [Operation of the fluid transport device 10]

[0073] When the drive circuit 53 supplies three-phase AC power to the excitation coil 51, a rotating magnetic field is formed around the casing 21. A magnetic force acts on the magnetic material 24 in this rotating magnetic field, causing the casing 21 to rotate. The spiral blades 22 rotate together with the casing 21. The rotating spiral blades 22 create a helical vortex in the fluid, transporting the fluid flowing into the casing 21 from one side to the other side.

[0074] The direction in which the fluid is transported is determined by the direction of rotation of the casing 21 and the spiral blades 22. The direction of rotation of the casing 21 and the spiral blades 22 is determined by the direction of the rotating magnetic field formed by the excitation coil 51. Since the direction of the rotating magnetic field is controlled by the drive circuit 53 (driver IC), the fluid transport device 10 can arbitrarily adjust the direction of fluid transport.

[0075] [Effects of the Embodiment]

[0076] As shown in Figures 1 and 2, the spiral blades 22 are projected from the inner circumferential surface 31 of the casing 21, so there is no rotating shaft with blades inside the casing 21. Therefore, compared to conventional fluid conveying devices, the cross-sectional area and volume of the fluid flow path are increased, and as a result, the conveying efficiency of the fluid conveyor 20 or fluid conveying device 10 is improved.

[0077] In addition, since the spiral blades 22 protrude from the inner circumferential surface 31 of the casing 21, no gap is created between the spiral blades 22 and the inner circumferential surface 31 of the casing 21. Therefore, there is an advantage that the fluid being conveyed does not get stuck between the spiral blades 22 and the inner circumferential surface 31 of the casing 21.

[0078] In this embodiment, a central channel 34 is formed around the central axis 6 of the casing 21, so the fluid is smoothly transported by passing through the central channel 34. Therefore, even if the fluid contains particles with a relatively large outer diameter, malfunctions due to clogging by the particles are suppressed.

[0079] In this embodiment, the rotating magnetic field generated by the excitation coil 51 imparts rotational torque to the casing 21 to which the magnetic material 24 is attached. That is, the casing 21 is rotated non-contactually, rather than via gears or belts. Therefore, the durability of the fluid conveying device 10 is improved.

[0080] [Example 1]

[0081] Figure 9 is a perspective view of a partially cut section of the fluid conveyor 70 according to Modification 1 of this embodiment. Figure 10 is a view taken along the line X in Figure 9. Figure 11 is a cross-sectional view of the fluid conveyor 70.

[0082] The fluid conveyor 70 according to this modified example has protruding blades 71, 72, and 73 instead of spiral blades 22 (see Figures 2 and 4). In the following description, components similar to those in the fluid conveying device 10 described above are given the same reference numerals and their descriptions are omitted.

[0083] The fluid conveying device 10 comprises a fluid conveyor 70 (see Figure 9), a support mechanism 40, a drive device 50, and a joint 60 (see Figure 1). The support mechanism 40 supports the fluid conveyor 70 so that it can rotate around a central axis 6. The drive device 50 rotates the fluid conveyor 70. The joint 60 connects the fluid conveyor 70 to the pipe 11.

[0084] As shown in Figures 9 to 11, the fluid conveyor 70 has a casing 21 and three protruding blades 71, 72, and 73. The number of protruding blades N is not limited to three; it can be two or more. In other words, N is an integer greater than or equal to 2.

[0085] As shown in Figures 9 and 10, the protruding blade 71 has an outer edge 130 (see Figure 10), an inner edge 131, a pair of side edges 132 and 133, and a pair of helical surfaces 134 and 135 that are aligned with the inner circumferential surface 31 of the casing 21. The helical surfaces 134 and 135 are on opposite sides. In this modified example, the thickness 122 of the protruding blade 71 is the same as the thickness 26 of the spiral blade 22 according to the above embodiment. The side edges 132 and 133 are continuous with both ends of the inner edge 131 and are continuous with the inner circumferential surface 31.

[0086] The protruding blades 72 and 73 have the same shape as the protruding blade 71. The protruding blade 72 has an outer edge 140, an inner edge 141, a pair of side edges 142 and 143, and a pair of helical surfaces 144 and 145, with helical surfaces 144 and 145 being in a front-and-back relationship. The protruding blade 73 has an outer edge 150, an inner edge 151, a pair of side edges 152 and 153, and a pair of helical surfaces 154 and 155, with helical surfaces 154 and 155 being in a front-and-back relationship. The outer edges 130, 140, and 150 correspond to each other, and the inner edges 131, 141, and 151 correspond to each other. The side edges 132, 142, and 152 correspond to each other, and the side edges 133, 143, and 153 correspond to each other. The helical surfaces 134, 144, and 154 correspond to each other, and the helical surfaces 135, 145, and 155 correspond to each other.

[0087] In Figure 9, the shaded area 77 corresponds to the outer edges 130, 140, and 150, and this area 77 is the connection portion (welded portion) between the protruding blades 71, 72, and 73 and the inner circumferential surface 31 of the casing 21.

[0088] As shown in Figure 10, the three protruding blades 71, 72, and 73 are fixed to the inner circumferential surface 31 of the casing 21 and each protrudes inward from the inner circumferential surface 31. In this modified example, the three protruding blades 71, 72, and 73 are arranged at equal intervals (120-degree intervals) around the central axis 6. The material constituting the protruding blades 71, 72, and 73 is the same as that of the casing 21. The protruding blades 71, 72, and 73 are made of, for example, rectangular flat bars. By bending these flat bars through press working, the protruding blades 71, 72, and 73 shown in Figure 9 are formed. The above-mentioned regions 77 of the protruding blades 71, 72, and 73 are welded to the inner circumferential surface 31 of the casing 21, and the protruding blades 71, 72, and 73 are integrally formed with the casing 21.

[0089] As shown in Figure 10, the projection length 79 of the projection vane 71 is appropriately designed according to the properties of the fluid being conveyed. The projection length 79 is constant in the circumferential direction 9, and in this modified example, the projection length 79 is less than half the inner diameter 111 of the casing 21 (less than the radius of curvature of the inner circumferential surface 31). This forms a central flow channel 125 around the central axis 6. In Figure 9, the central flow channel 125 is shown by a dashed line. The central flow channel 125 is formed by the inner edges 131, 141, and 151 inside the projection vanes 71, 72, and 73, and extends along the axial direction 7.

[0090] As shown in Figure 10, the sides 132 and 133 of the protruding blade 71 extend along the radial direction 8. The angle at which the direction in which side 132 extends intersects with the direction in which side 133 extends is 120 degrees. The same applies to the protruding blades 72 and 73. In this modified example, the side 133 of the protruding blade 71 and the side 142 of the protruding blade 72 are separated by a distance of 78 in the circumferential direction 9. The relationship between the side 143 of the protruding blade 72 and the side 152 of the protruding blade 73, and the relationship between the side 153 of the protruding blade 73 and the side 132 of the protruding blade 71 are similar. This distance 78 can be set as appropriate.

[0091] Figure 12 illustrates the positional relationship between the protruding blades 71, 72, and 73 in the axial direction 7, and the positional relationship between the virtual helices 74, 75, and 76 that serve as the reference.

[0092] In this modified example, as shown in Figure 9, the protruding blades 71, 72, and 73 form a so-called triple helix. That is, the protruding blades 71, 72, and 73 are arranged in a positional relationship similar to the positional relationship between the threads of a triple-start screw. Figure 12 schematically shows the positional relationship of the protruding blades 71, 72, and 73.

[0093] A three-start thread is virtually formed inside the casing 21. In the figure, reference numerals 74, 75, and 76 indicate the trajectory of this thread when unfolded in a plane, and are referred to herein as the first virtual helix 74, the second virtual helix 75, and the third virtual helix 76. Therefore, the pitch 124 (corresponding to "pitch (P)" in the claims) of the first virtual helix 74, the second virtual helix 75, and the third virtual helix 76 are the same, and the first virtual helix 74 and the second virtual helix 75 are relatively displaced by 1 / 3 of the pitch 124 (corresponding to "P / N" in the claims) in the axial direction 6. The positional relationship between the second virtual helix 75 and the third virtual helix 76, and the positional relationship between the third virtual helix 76 and the first virtual helix 74 are similar. In other words, the first virtual helix 74, the second virtual helix 75, and the third virtual helix 76 are displaced relative to each other by an angle of 120 degrees around the central axis 6.

[0094] In the figure, the dashed lines 71, 72, and 73 indicate the positions of the protruding blades 71, 72, and 73, respectively, which are positioned along the first virtual spiral 74, the second virtual spiral 75, and the third virtual spiral 76.

[0095] The helical surfaces 134 and 135 of the projection vane 71 extend along the first virtual helix 74. Therefore, the projection vane 71 is inclined with respect to the axial direction 7 and the radial direction 8. This inclination angle is defined by the angle of the first virtual helix 74 with respect to the virtual cross-section 12 (helical angle α), as shown in Figure 11. Similarly, the helical surfaces 144 and 145 of the projection vane 72 extend along the second virtual helix 75, and the helical surfaces 154 and 155 of the projection vane 73 extend along the third virtual helix 76.

[0096] As shown in Figure 9, the protruding blades 71, 72, and 73 are arranged so as to divide the inner circumferential surface 31 of the casing 21 into three equal parts in the circumferential direction. Therefore, as shown in Figure 12, the length 126 (distance between the side 132 and side 133) of the protruding blade 71 extending in the axial direction 7 is approximately 1 / 3 of the pitch 124 of the first virtual helix 74. The same applies to the lengths 126 of the protruding blades 72 and 73 extending in the axial direction 7.

[0097] [Effects of Modification 1]

[0098] As shown in Figures 9 to 11, the protruding blades 71, 72, and 73 are inclined with respect to the axial direction 7 and the radial direction 8, so that the rotating protruding blades 71, 72, and 73 can transport fluid from one direction in the axial direction 7 to the other. Since the protruding blades 71, 72, and 73 are projected from the inner circumferential surface 31 of the casing 21, there is no rotating shaft with blades inside the casing 21. Therefore, compared to conventional fluid transport devices, the cross-sectional area and volume of the fluid flow path are increased, and as a result, the transport efficiency of the fluid transporter 70 or fluid transport device 10 is improved.

[0099] Since the protruding blades 71, 72, and 73 extend along the virtual helices 74, 75, and 76 (see Figure 12), the three protruding blades 71, 72, and 73 constitute part of the threads of a triple-start screw. Therefore, the fluid conveyor 70 can efficiently convey fluid.

[0100] In addition, since the protruding blades 71, 72, and 73 are positioned to protrude from the inner circumferential surface 31 of the casing 21, no gaps are created between the protruding blades 71, 72, and 73 and the inner circumferential surface 31 of the casing 21. Therefore, there is an advantage that the fluid being conveyed will not become clogged between the protruding blades 71, 72, and 73 and the inner circumferential surface 31 of the casing 21.

[0101] In this modified example, a central channel 125 is formed around the central axis 6 of the casing 21 (see Figure 9), so the fluid is smoothly transported through the central channel 125. Therefore, even if the fluid contains particles with a relatively large outer diameter, malfunctions due to clogging by the particles are suppressed.

[0102] In the fluid conveyor 70 according to this modified example, the protruding blades 71, 72, and 73 extend along the virtual helices 74, 75, and 76, and the protruding blades 71, 72, and 73 have a curved shape. However, the protruding blades 71, 72, and 73 may also be flat. Making the protruding blades 71, 72, and 73 flat makes it easier to manufacture the fluid conveyor 70.

[0103] [Differentiation 2]

[0104] Figure 13 is a cross-sectional view of a fluid conveying device 80 according to a modified example 2, which includes a fluid conveyor 20 according to the embodiment.

[0105] The fluid conveying device 80 employs a pair of bearings 81 instead of the support mechanism 40 (see Figure 1). The pair of bearings 81 function as a support for the fluid conveyor 20. Note that configurations other than those described below are the same as those described in the above embodiment; therefore, the same reference numerals are used for components identical to those in the above embodiment, and their descriptions are omitted.

[0106] As shown in Figure 13, the fluid conveying device 80 comprises a fluid conveyor 20, a drive unit 50, a joint 60, and a pair of bearings 81.

[0107] One bearing 81 is located at one end of the casing 21 in the axial direction 7, and the other bearing 81 is located at the other end of the casing 21. The magnetic material 24 is located between the pair of bearings 81 in the axial direction 7. The bearing 81 comprises an outer ring 82, an inner ring (not shown), a cage (not shown), and a plurality of rolling elements 83. The rolling elements 83 are balls or needles. The cage positions the rolling elements 83 and holds them rotatably. Standard (commercially available) bearings 81 can be used.

[0108] [Difference 3]

[0109] Figure 14 is a cross-sectional view of a fluid conveying device 90 according to a modified example 3, which includes a fluid conveyor 20 according to the embodiment.

[0110] The fluid transport device 90 has a motor 94, a drive gear 96, and a coupling gear 92, and the casing 21 is rotated by this mechanism. Note that configurations other than those described below are the same as those described in the above embodiment; therefore, the same reference numerals are used for the same configurations as in the above embodiment, and their description is omitted.

[0111] As shown in Figure 14, the fluid transport device 90 comprises a fluid transporter 20, a support mechanism 40, a joint 60, and a drive device 93. The drive device 93 comprises a connecting gear 92 provided on the fluid transporter 20, and a motor 94, a drive gear 96, and a printed circuit board 97 provided on the frame 41 side.

[0112] The connecting gear 92 is ring-shaped and fixed to the outer circumferential surface 32 of the casing 21. The motor 94 may be a DC motor or an AC motor. The drive gear 96 is fixed to the drive shaft 95 of the motor 94. The drive gear 96 meshes with the connecting gear 92, and when the drive gear 96 rotates together with the drive shaft 95, the casing 21 rotates via the connecting gear 92.

[0113] The printed circuit board 97 has various electronic components mounted on it. These components include connectors, resistors, capacitors, diodes, coils, and ICs. Lead wires from the motor 94 are connected to the connectors. These lead wires electrically connect the motor 94 and the printed circuit board 97. The IC mentioned above is, for example, a commercially available motor driver IC.

[0114] The motor 94's drive circuit is formed by the printed circuit board 97 and various electronic components mounted on the printed circuit board 97. This drive circuit converts power supplied from a power source (not shown) into drive power such as pulsed power or three-phase AC power and supplies it to the motor 94. When drive power is supplied to the motor 94, the casing 21 rotates as described above, and the spiral blades 22, which rotate together with the casing 21, transport the fluid.

[0115] [Effects of Modification 3]

[0116] The casing 21 can be rotated with a simple configuration consisting of the motor 94 and gears 92 and 96.

[0117] [Differentiation Example 4]

[0118] Figure 15 is a cross-sectional view of a fluid conveying device 100 according to a modified example 4, which includes a fluid conveyor 20 according to the embodiment.

[0119] In the fluid transport device 10 described in the above embodiment, the casing 21 is rotated by the excitation coil 51 and the magnetic material 24, whereas in the fluid transport device 100 described in this modified example, the casing 21 is rotated by the motor 94, the drive pulley 103, the driven pulley 104, and the endless ring belt 105. Note that configurations other than those described below are the same as those described in the above embodiment and modified example. Components identical to those in the above embodiment and modified example are denoted by the same reference numerals and their descriptions are omitted.

[0120] The fluid conveying device 100 comprises a fluid conveyor 20, a support mechanism 40, a joint 60, and a drive device 102. The drive device 102 comprises a driven pulley 104 on the fluid conveyor 20 side, and a motor 94, a drive pulley 103, an endless belt 105, and a printed circuit board 97 on the frame 41 side.

[0121] The driven pulley 104 is fixed to the outer circumferential surface 32 of the casing 21. The drive pulley 103 is fixed to the drive shaft 95 of the motor 94. The endless belt 105 is wrapped around the drive pulley 103 and the driven pulley 104. When the drive pulley 103 rotates, the driven pulley 104 and the casing 21 rotate via the endless belt 105.

[0122] [Effects of Modification 4]

[0123] The casing 21 can be rotated by a simple configuration consisting of a motor 94, pulleys 103 and 104, and an endless belt 105.

[0124] [Other variations]

[0125] In the above embodiments and their respective modifications, the protruding width 123 of the spiral blade 22 and the protruding lengths 79 of the protruding blades 71, 72, and 73 are set to less than half of the inner diameter 111 of the casing 21, thereby forming central passages 34 and 125. However, the protruding width 123 and protruding lengths 79 may be set to be the same as half of the inner diameter 111 of the casing 21, and the central passages 34 and 125 may not be formed.

[0126] In the above embodiment, the casing 21 is rotatably supported by the support mechanism 40 and the joint 60, but if the joint 60 is used, the casing 21 may be rotatably supported by the joint 60 alone. The joint 60 functions as a support for the fluid carrier 20.

[0127] In the above embodiment, the fluid conveying device 10 is equipped with a joint 60. However, if the fluid conveying device 10 is not connected to the pipe 11, such as when it is used as a propulsion system for a ship, the fluid conveying device 10 does not need to be equipped with a joint 60.

[0128] In the above embodiment, the casing 21 is supported via rolling elements 42 and bearings 81, but instead, the casing 21 may be rotatably supported by air bearings using compressed air or by bushings.

[0129] In the above embodiments and their variations, examples were described in which the casing 21, spiral blades 22, and protruding blades 71, 72, and 73 are made of metal. However, the casing 21, spiral blades 22, and protruding blades 71, 72, and 73 may be made of resin. For example, the casing 21, spiral blades 22, and protruding blades 71, 72, and 73 may be manufactured from fiber-reinforced plastic (FPR). Typically, when the fluid being conveyed is corrosive to metal and has low conveying resistance, the casing 21, spiral blades 22, and protruding blades 71, 72, and 73 are made of resin. [Explanation of Symbols]

[0130] 6...Central axis 7...Axis 8. Radial direction 9...Circumferential direction 10, 80, 90, 100... Fluid conveying equipment 11.. Pipe 20, 70... Fluid conveyors 21. Casing 22... Spiral feathers 24...Magnetic material 31...Inner surface 32...outer surface 34, 125... Central channel 40...Support mechanism 41...frame 42, 83... Rolling elements (supports) 50, 93, 102... Drive unit 51...Excitation coil 53...Drive Circuit 57, 97... Printed circuit board 60... Joint 63. Seal component 68...filter 71, 72, 73... Protruding wings 79... protruding length 81.. Bearing 111... Inner diameter 112... Outer diameter 121, 124... pitch 123...Protrusion width

Claims

1. A cylindrical casing into which the fluid is supplied, A fluid conveyor comprising spiral blades protruding from the inner circumferential surface of the casing and extending spirally along the central axis of the casing at a predetermined pitch.

2. A cylindrical casing into which the fluid is supplied, The casing comprises N (where N is multiple) protruding blades, each protruding from the inner circumferential surface of the casing and arranged at equal intervals around the central axis of the casing. A fluid conveyor in which the above-mentioned protruding blades are inclined with respect to the direction of the central axis and radial direction of the casing in order to convey the above-mentioned fluid by rotating about the above-mentioned central axis.

3. The fluid conveyor according to claim 2, wherein the N protruding blades are arranged along N virtual helices that extend in the direction of the central axis at a predetermined pitch (P) and are displaced by P / N along the central axis.

4. The fluid conveyor according to claim 3, wherein the above-mentioned protruding blades are three in number.

5. The fluid conveyor according to claim 1, wherein the radial projection width of the spiral blades from the casing is less than half the inner diameter of the casing.

6. The fluid conveyor according to any one of claims 2 to 4, wherein the radial projection length of the above-mentioned protruding vane from the above-mentioned casing is less than half of the inner diameter of the casing.

Images