Pump

Abstract

To provide a pump including a vortex suppression member which can set an opening area to be wider while maintaining the strength.SOLUTION: The pump includes a cylindrical casing 2 in which an impeller 12 is provided to be rotationally driven, and which has a suction port 2a for water in the lower end and a discharge pipe 3 connected to the upper end side, and a vortex suppression member 4 provided in the suction port, the vortex suppression member including an upper frame member 4a mounted at the lower end outer peripheral edge of the suction port and having the same diameter as the suction port, a plurality of frame support members 4b having upper ends fixed to the upper frame member, arranged at mutual spaces in a peripheral direction of the upper frame member, and extending downward, and a lower frame member 4c fixed to the lower ends of the plurality of frame support members, the lower frame member having a smaller diameter than the upper frame member, the plurality of frame support members being arranged obliquely with respect to a vertical axis while gradually narrowing the spaces toward the lower frame member.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a pump that can suppress the occurrence of vortexes when pumping water from a suction tank or the like. [Background technology]

[0002] When pumping water from a suction tank connected to a river, etc., vortices may occur in the suction tank. In particular, when the water level drops as the water is discharged, vortices that suck in air from the water surface (air-sucking vortices) may occur and be drawn into the pump. If air is sucked into the pump due to such an air-sucking vortex, the density of the water flow changes, causing it to lose balance, which can cause vibrations in the pump and reduce the pump efficiency.

[0003] As a countermeasure against vortex currents, for example, Patent Document 1 proposes a pump 100 as shown in Figures 8 and 9, which comprises a cylindrical casing 2 having a rotationally driven impeller 12 inside, a water inlet 2a at its lower end, and a discharge pipe 3 connected to its upper end, and a vortex current suppression member 104 provided at the suction port 2a, where the vortex current suppression member 104 has a rotating shaft 104b and a rotating plate 104a that can be rotated by the water flow sucked into the suction port 2a.

[0004] The vortex current suppression member 104 includes an upper support member 104c fixed to the lower end of the casing 2 and rotatably supporting an upper portion of the rotating shaft 104b, a lower support member 104d rotatably supporting a lower portion of the rotating shaft 104b, and a plurality of connecting rods 104e that connect the upper and lower ends of the upper support member 104c and the lower support member 104d radially outside the rotating plate 104a and are arranged at intervals from each other in the circumferential direction. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2020-193604 A Summary of the Invention [Problem to be solved by the invention]

[0006] The above-mentioned conventional techniques have the following problems remaining. In the conventional technology described in Patent Document 1, the circumferential spacing of the four connecting rods 104e that serve as ribs is widened to increase the opening area of ​​the outer peripheral surface so as to make it easier to take in the water current that is sucked into the vortex current suppression member 104, but there is a problem in that the strength is reduced because there are too few connecting rods 104e that serve as ribs. For this reason, as in the reference example shown in Figure 10, for example, the strength can be improved by covering the outer peripheral surface and bottom surface of the vortex current suppression member 114 in a lattice pattern with many connecting rods 114e, but conversely, there is a problem in that the opening area of ​​the outer peripheral surface is reduced.

[0007] The present invention has been made in consideration of the above-mentioned problems in the conventional art, and has an object to provide a pump equipped with a vortex suppression member that can be set to have a wide opening area while maintaining strength. [Means for solving the problem]

[0008] The present invention employs the following configuration to solve the above problems. That is, a pump according to a first aspect of the invention comprises a cylindrical casing having an impeller that is rotated and a water inlet at its lower end and a discharge pipe connected to its upper end, and a vortex current suppression member provided at the suction port, the vortex current suppression member comprising an upper frame member attached to the outer periphery of the lower end of the suction port and having the same diameter as the suction port, a plurality of frame support members whose upper ends are fixed to the upper frame member, arranged at intervals in the circumferential direction of the upper frame member and extending downward, and a lower frame member fixed to the lower ends of the plurality of frame support members, the lower frame member having a smaller diameter than the upper frame member, the intervals between the plurality of frame support members gradually narrowing toward the lower frame member, and the plurality of frame support members being arranged at an angle with respect to a vertical axis.

[0009] In this pump, the lower frame member has a smaller diameter than the upper frame member, so that the strength is improved compared to when the upper and lower frame members have the same diameter. In addition, the multiple frame support members are arranged diagonally with respect to the vertical axis with the intervals gradually narrowing toward the lower frame member, so that the multiple frame support members are concentrated toward the center, i.e., the lower frame member with a smaller diameter, as they move downward, so that it is possible to maintain strength even if the number of multiple frame support members that serve as ribs is reduced and the opening area of ​​the outer circumferential surface is increased. Furthermore, the opening surrounded by the large-diameter upper frame member, the small-diameter lower frame member, and the frame support member extending diagonally toward the lower frame member opens diagonally downward, making it easier to take in water flow from diagonally downward.

[0010] The pump according to a second aspect of the present invention is the pump according to the first aspect of the present invention, further comprising an intermediate frame member fixed to the frame support member and extending horizontally. In other words, this pump has an intermediate frame member fixed to the frame support member and extending horizontally between the upper frame member and the lower frame member, so that the space between the upper frame member and the lower frame member can be reinforced with the intermediate frame member.

[0011] The pump of the third invention is a pump installed in a suction tank in the second invention, characterized in that a plurality of intermediate frame members are provided between the upper frame member and the lower frame member at intervals in the vertical direction, and at least one of the plurality of intermediate frame members is arranged only on the downstream side of the suction tank and not on the upstream side. In other words, in this pump, at least one of the multiple intermediate frame members is arranged only on the downstream side of the suction tank and not on the upstream side, so that the opening area on the upstream side of the suction tank can be set large.

[0012] The pump of the fourth invention is characterized in that, in any of the first to third inventions, the lower frame member is provided with a base portion that protrudes downward at the lower part and has a bottom surface that is a horizontal plane. That is, in this pump, the lower frame member is provided with a base portion that protrudes downward at the bottom and has a horizontal bottom surface, and the base portion protruding downward can suppress the generation of vortex currents directly below. Also, when attaching the vortex suppression member to the suction port, by placing the vortex suppression member on the bottom surface of the suction tank with the base portion facing down, the vortex suppression member will not fall over and the installation work will be easier.

[0013] The pump of the fifth invention is characterized in that, in the second or third invention, it has a plurality of rotating plates attached so as to be rotatable by the water flow with at least one of the intermediate frame member and the lower frame member as a central axis. That is, this pump is provided with multiple rotating plates that are attached so as to be rotatable by the water flow around at least one of the middle frame member and the lower frame member as a central axis, so that the rotating plates rotate due to the water flow sucked into the suction port, thereby making it possible to prevent dirt and the like from becoming entangled. However, if dirt and the like becomes entangled, the water flow may become biased, causing vibration.

[0014] The pump of the sixth invention is characterized in that, in the fourth invention, at least two of the plurality of rotating plates are arranged adjacent to each other, and one of the adjacent rotating plates is arranged to be rotatable in the opposite direction to the other adjacent rotating plate. In other words, in this pump, one of the adjacent rotating plates is arranged to be rotatable in the opposite direction to the other adjacent rotating plate, so that if debris or the like becomes tangled, the debris or the like can be crushed by the rotating plates rotating in opposite directions. Effect of the Invention

[0015] According to the present invention, the following effects are obtained. In other words, according to the pump of the present invention, the lower frame member has a smaller diameter than the upper frame member, and the multiple frame support members are arranged diagonally with respect to the vertical axis with the spacing between them gradually narrowing toward the lower frame member, thereby improving strength and making it possible to maintain strength even if the number of multiple frame support members that act as ribs is reduced and the opening area of ​​the outer peripheral surface is increased. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a side view showing a pump installed in a suction sump with the suction sump cut away in a first embodiment of the pump according to the present invention. [Diagram 2] FIG. 2 is a perspective view showing a vortex current suppression member in the first embodiment. [Diagram 3] 2 is a side view showing the vortex current suppression member in the first embodiment. FIG. [Figure 4] FIG. 11 is a perspective view showing a vortex suppression member in a second embodiment of a pump according to the present invention. [Diagram 5] FIG. 11 is a side view showing a vortex current suppression member in the second embodiment. [Figure 6] FIG. 11 is a perspective view showing a vortex suppression member in a pump according to a third embodiment of the present invention. [Figure 7] FIG. 11 is a side view showing a vortex current suppression member in the third embodiment. [Figure 8] FIG. 1 is a side view showing a pump installed in a suction sump with the suction sump cut away in a conventional example of the pump according to the present invention. [Figure 9] FIG. 11 is a perspective view showing a vortex suppression member in a conventional example of the pump according to the present invention. [Figure 10] FIG. 2 is a perspective view showing a vortex suppression member in a reference example of a pump according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, a first embodiment of a pump according to the present invention will be described with reference to FIGS.

[0018] The pump 1 in this embodiment is a so-called vertical pump, and as shown in Figure 1, is installed in a suction tank 10. It has a cylindrical casing 2 that has a rotatably driven impeller 12 inside, a water inlet 2a at its lower end, and a discharge pipe 3 connected to its upper end, and a vortex suppression member 4 provided at the suction port 2a. The vortex suppression member 4 of this embodiment is attached to the lower end of the suction port 2 a , that is, the lower end of the casing 2 .

[0019] As shown in Figures 1 to 3, the vortex suppression member 4 comprises an upper frame member 4a that is attached to the outer peripheral edge of the lower end of the suction port 2a and has the same diameter as the suction port 2a, a plurality of frame support members 4b whose upper ends are fixed to the upper frame member 4a, which are arranged at intervals around the circumferential direction of the upper frame member 4a and extend downward, and a lower frame member 4c which is fixed to the lower ends of the plurality of frame support members 4b. The lower frame member 4c has a circular shape with a smaller diameter than the circular upper frame member 4a. The central axes of the upper frame member 4a and the lower frame member 4c coincide with each other. Moreover, the upper frame member 4a is fixed to the lower end of the casing 2 with bolts or the like.

[0020] The plurality of frame support members 4b are arranged at an angle to the vertical axis, with the intervals between each of them gradually narrowing toward the lower frame member 4c. That is, the frame support members 4b extend inwardly and curvedly toward the central axis of the upper frame member 4a and the lower frame member 4c as they approach the lower part. In this embodiment, four frame support members 4b are provided at equal intervals in the circumferential direction.

[0021] Furthermore, the vortex current suppression member 4 includes an intermediate frame member 4d between the upper frame member 4a and the lower frame member 4c, the intermediate frame member 4d being fixed to the frame support member 4b and extending horizontally. The intermediate frame members 4d are provided in multiple locations between the upper frame member 4a and the lower frame member 4c, with gaps between them vertically, and at least one of the multiple intermediate frame members 4d is arranged only on the downstream side (left side in Figure 1) of the suction tank 10, and not on the upstream side (right side in Figure 1).

[0022] That is, the intermediate frame member 4d of this embodiment is provided in two stages, an upper stage and a lower stage, with a gap between them in the vertical direction, between the upper frame member 4a and the lower frame member 4c. The upper intermediate frame member 4d has an arc shape extending halfway around the circumference, while the lower intermediate frame member 4d extends in a circular shape with the same central axis as the lower frame member 4c. In this way, the upper intermediate frame member 4d is arranged in an arc shape only on the downstream side (left side in FIG. 1) of the suction sump 10, and is not arranged on the upstream side (right side in FIG. 1).

[0023] In other words, there is no upper intermediate frame member 4d in the upstream circumferential half of the vortex current suppression member 4, and a wide opening K facing the upstream side, i.e., the opening K surrounded by the upper frame member 4a, the frame support member 4b and the lower frame member 4c, is secured. The vortex suppression member 4 has a bowl shape with an outer diameter that gradually decreases downward.

[0024] The lower frame member 4c is provided with a base portion 6 that protrudes downward at its lower portion and has a horizontal bottom surface. The pedestal portion 6 is provided in a cross shape when viewed from the bottom, and is made up of four long plates extending in the cross direction from the central axis of the lower frame member 4c. In other words, the bottom surface of the cross shape of the pedestal portion 6 is a horizontal surface.

[0025] The suction tank 10 stores water such as rainwater, and as shown in FIG. 1, has an end wall 10b that closes the downstream side with respect to the inflow direction of water. In addition, the upper part of the suction tank 10 is covered with an installation floor 10c, and the pump 1 is suspended by fixing the flange portion 2b on the upper part of the casing 2 to a pump base (base plate) 10d attached to an installation hole 10e opened in the suction floor 10c. The pump 1 of this embodiment is installed near the end wall 10b, and is installed with the suction port 2a disposed at a position spaced above the bottom surface 10a of the suction tank 10.

[0026] In this manner, in the pump 1 of this embodiment, the lower frame member 4c has a smaller diameter than the upper frame member 4a, and therefore the strength is improved compared to when the upper frame member 4a and the lower frame member 4c have the same diameter. In addition, since the multiple frame support members 4b are arranged diagonally with respect to the vertical axis with the spacing between them gradually narrowing toward the lower frame member 4c, the multiple frame support members 4b are concentrated toward the center, i.e., the smaller diameter lower frame member 4c, as they move downward. This makes it possible to maintain strength even if the number of multiple frame support members 4b that act as ribs is reduced and the opening area of ​​the outer peripheral surface is increased.

[0027] Furthermore, the opening K surrounded by the large diameter upper frame member 4a, the small diameter lower frame member 4c, and the frame support member 4b extending diagonally toward the lower frame member 4c opens diagonally downward, making it easier to take in water flowing from diagonally below. In particular, since at least one of the multiple intermediate frame members 4d is disposed only on the downstream side of the suction sump 10 and not on the upstream side, the opening area on the upstream side of the suction sump 10 can be set large. In addition, an intermediate frame member 4d having an outer diameter smaller than that of the upper frame member 4a and larger than that of the lower frame member 4c is provided between the upper frame member 4a and the lower frame member 4c, so that the space between the upper frame member 4a and the lower frame member 4c can be reinforced by the intermediate frame member 4d.

[0028] In addition, since the lower frame member 4c is provided with a base portion 6 that protrudes downward at the bottom and has a horizontal bottom surface, the base portion 6 protruding downward can suppress the generation of vortex currents directly below. Furthermore, when attaching the vortex suppression member 4 to the suction port 2a, by placing the vortex suppression member 4 on the bottom surface 10a of the suction tank 10 with the base portion 6 facing down, the vortex suppression member 4 will not fall over, making the attachment work easier.

[0029] Next, a second and third embodiment of the pump according to the present invention will be described below with reference to Figures 4 to 7. In the following description of each embodiment, the same components as those described in the above embodiments are denoted by the same reference numerals, and the description thereof will be omitted.

[0030] The difference between the second embodiment and the first embodiment is that in the first embodiment, the lower intermediate frame member 4d simply extends in a circular ring shape, whereas the pump of the second embodiment is provided with a plurality of rotating plates 27 that are attached so as to be rotatable by the water flow around the lower intermediate frame member 24d as the central axis, as shown in Figures 5 and 6. That is, in the second embodiment, the four lower intermediate frame members 24d bridged between adjacent frame support members 4b each extend linearly, and a rotatable rotating plate 27 is attached to each intermediate frame member 24d.

[0031] The rotating plate 27 has three long plate-like fins 27a protruding from the outer circumferential surface at equal intervals, and the fins 27a protrude at an incline so as to be rotatable in a specific rotation direction by the water flow. In this embodiment, the rotating plate 27 is attached to the lower intermediate frame member 24d, but the rotating plate 27 may be provided on the lower frame member 4c or the upper intermediate frame member 4d. In this way, the pump of the second embodiment is provided with a plurality of rotating plates 27 that are attached so as to be rotatable by the water flow around at least one of the intermediate frame member 24d and the lower frame member 4c as a central axis. Therefore, the rotating plates 27 rotate due to the water flow sucked into the suction port, thereby preventing debris and the like from becoming entangled.

[0032] Next, the difference between the third embodiment and the second embodiment is that in the second embodiment, one rotating plate 27 is rotatably mounted on one intermediate frame member 24d mounted on adjacent frame support members 4b, whereas in the pump of the third embodiment, multiple rotating plates 37 are rotatably mounted adjacent to each other on one intermediate frame member 24d mounted on adjacent frame support members 4b, as shown in Figures 7 and 8.

[0033] That is, in the third embodiment, at least two of the multiple rotating plates 37 are arranged adjacent to each other, and one of the adjacent rotating plates 37 is arranged to be rotatable in the opposite direction to the other adjacent rotating plate 37. In the third embodiment, three rotating plates 37 are arranged side by side on one intermediate frame member 24d, and the central rotating plate 37 is rotatable in a direction opposite to the direction of rotation of the rotating plates 37 on both sides. Thus, in the pump of the third embodiment, one of the adjacent rotating plates 37 is arranged to be rotatable in the opposite direction to the other adjacent rotating plate 37, so that if dirt or the like becomes tangled, the dirt or the like can be crushed by the rotating plates 37 which rotate in the opposite directions.

[0034] The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

[0035] For example, the pumps in the above embodiments are vertical shaft pumps, but the present invention may be applied to horizontal shaft pumps as another example of the above embodiments. That is, in a vertical shaft pump, the impeller is disposed in the lower part of the casing and the rotation shaft of the impeller extends vertically, whereas in a horizontal shaft pump, the impeller is disposed in the upper part of the casing (including the discharge pipe) and the rotation shaft of the impeller extends horizontally. It would be useless to attach the vortex suppression member to the suction port of such a horizontal shaft pump. [Explanation of symbols]

[0036] Reference Signs List 1... pump, 2... casing, 2a... suction port, 3... discharge pipe, 4, 24, 34... vortex suppression member, 4a... upper frame member, 4b... frame support member, 4c... lower frame member, 4d, 24d... intermediate frame member, 6... base portion, 10... suction water tank, 12... impeller, 27, 37... rotating plate

Claims

1. a cylindrical casing having a rotationally driven impeller therein, a water inlet at a lower end, and a discharge pipe connected to an upper end side; A vortex suppression member provided at the suction port, The vortex suppression member includes an upper frame member attached to a lower end outer peripheral edge of the suction port and having the same diameter as the suction port; a plurality of frame support members each having an upper end fixed to the upper frame member, being spaced apart from one another in a circumferential direction of the upper frame member, and extending downward; a lower frame member fixed to lower ends of the plurality of frame support members, the lower frame member has a smaller diameter than the upper frame member, A pump comprising: a pump body having a plurality of frame support members, the spacing between which gradually narrows toward the lower frame member and which are disposed obliquely relative to a vertical axis.

2. 2. The pump of claim 1, A pump comprising an intermediate frame member fixed to said frame support member and extending horizontally between said upper frame member and said lower frame member.

3. 3. The pump according to claim 2, A pump installed in a suction tank, The intermediate frame members are provided in a plurality of positions vertically spaced apart from one another between the upper frame member and the lower frame member, A pump characterized in that at least one of the multiple intermediate frame members is arranged only on the downstream side of the suction tank and not on the upstream side.

4. A pump according to any one of claims 1 to 3, A pump characterized in that the lower frame member is provided with a base portion that protrudes downward at a lower portion and has a bottom surface that is a horizontal plane.

5. 4. The pump according to claim 2 or 3, A pump comprising a plurality of rotating plates attached so as to be rotatable by water flow around at least one of the intermediate frame member and the lower frame member as a central axis.

6. 6. The pump according to claim 5, At least two of the rotating plates are disposed adjacent to each other, A pump, characterized in that one of the adjacent rotary plates is rotatable in a direction opposite to that of the other adjacent rotary plate.

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