Submersible pump

Abstract

The present invention provides a submersible pump that can reliably maintain both a blocked and exposed state for the suction port that draws in air from the side. [Solution] The submersible pump 1 comprises an outer cover 2, a casing 3 connected to the lower end of the outer cover 2, a strainer 4 positioned below the casing 3, and a fastening member 5 that fixes the strainer 4 to the casing 3. The casing 3 has a side opening 31A at its lower end. The strainer 4 includes a side suction hole 42A at its upper end. The strainer 4 is configured to transition between a first position and a second position relative to the casing 3. In the first position, the positions of the side opening 31A and the side suction hole 42A coincide. In the second position, the positions of the side opening 31A and the side suction hole 42A do not coincide. The first and second positions are held by the fastening member 5.

Description

Technical Field

[0005] ,

[0001] The present invention relates to a submersible pump.

Background Art

[0002] In drainage or pumping scenarios such as during flooding caused by heavy rain, submersible pumps that place at least part of the pump body in the liquid are widely used. Patent Document 1 discloses an example of a conventional submersible pump. The submersible pump disclosed in this document has a base with a shell and a slide-type bottom plate. In this submersible pump, the size of the opening of the inlet changes by moving the bottom plate relative to the base. On the other hand, when the water level drops as drainage progresses, there is a risk of sucking air from the side suction holes, and in this case, drainage by the pump will no longer progress. The lower limit water level at which a submersible pump can drain is generally called the residual water level. By closing the side suction holes, the air intake start water level can be lowered, and the residual water level can be kept low, reducing the amount of liquid that remains.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Depending on the use of the submersible pump, it is required to reliably maintain the state where the suction holes for sucking from the side are blocked and the exposed state.

[0005] In view of the above circumstances, an object of the present invention is to provide a submersible pump capable of more reliably maintaining the state where the suction holes for sucking from the side are blocked and the exposed state.

Means for Solving the Problems

[0006] The submersible pump according to the present invention comprises an outer cover, a casing connected to the lower end of the outer cover, a strainer positioned below the casing, and fastening members for fixing the strainer to the casing. The casing includes a side surface with a side opening at its lower end. The strainer includes a bottom plate with a bottom suction hole, and a side wall with a side suction hole at its upper end and rising from the outer circumference of the bottom plate. The strainer is configured to transition between a first position and a second position relative to the casing. In the first position, the positions of the side opening and the side suction hole coincide, so that the side suction hole and the side opening communicate, and the outside and the inside of the casing are connected as a whole. In the second position, the positions of the side opening and the side suction hole do not coincide, so that the side suction hole and the side opening do not communicate, and the inside of the casing is separated from the outside by the side wall. The first position and the second position are held by the fastening member.

[0007] In a preferred example of the present invention, the height of the side suction hole is equal to the height of the side opening.

[0008] In a preferred example of the present invention, the casing is provided with a first fastening hole. The bottom plate is provided with a plurality of second fastening holes. The plurality of second fastening holes include a second fastening hole that coincides with the position of the first fastening hole at the first position, and another second fastening hole that coincides with the position of the first fastening hole at the second position.

[0009] In a preferred example of the present invention, the bottom plate is provided with auxiliary holes at the first and second positions that do not coincide with the positions of the plurality of first fastening holes.

[0010] In a preferred example of the present invention, the bottom plate is a flat surface.

[0011] Other features and advantages of this invention will become clearer from the detailed description below, based on the accompanying drawings. [Brief explanation of the drawing]

[0012] [Figure 1] This is a front view showing an example of a submersible pump according to the present invention. [Figure 2] This is a rear view showing a submersible pump according to an example of the present invention. [Figure 3] This is a right side view showing an example of a submersible pump according to the present invention. [Figure 4] This is a left side view showing a submersible pump according to an example of the present invention. [Figure 5] This is a plan view showing an example of a submersible pump according to the present invention. [Figure 6] This is a bottom view showing a submersible pump according to an example of the present invention. [Figure 7] This is an exploded perspective view showing a submersible pump according to an example of the present invention. [Figure 8] This figure shows an overview of the high water level state of a submersible pump according to an example of the present invention. [Figure 9] This figure shows an overview of the low water level state of a submersible pump according to an example of the present invention. [Modes for carrying out the invention]

[0013] Preferred embodiments of the present invention will be described below with reference to the drawings. The embodiments described below are examples, and the present invention is not limited to these embodiments.

[0014] Figures 1 to 9 illustrate a submersible pump 1 as an example of a submersible pump according to the present invention. The submersible pump 1 is positioned at least at the bottom in a liquid when in use and functions to suck in liquid and discharge it to the outside. The submersible pump 1 can switch between a high water level state H, which is suitable for draining liquid at a water level high enough to adequately suck in liquid from the side, and a low water level state L, which allows the remaining water level to be lower than in the high water level state H. Here, the high water level state H refers to a state in which suction is mainly performed from the side, and the low water level state L refers to a state in which suction from the side is suppressed and suction is mainly performed from the bottom.

[0015] The submersible pump 1 comprises an outer cover 2, a casing 3, a strainer 4, and fastening members 5. In the submersible pump 1, switching between a low water level state L and a high water level state H is performed by a relative movable configuration via the attachment and detachment of the fastening members 5. If necessary, a bolt cover covering the fastening members 5 may be provided on the outside of the fastening members 5. In the illustrated example, two fastening members 5 are arranged point-symmetrically with respect to the center of the strainer 4. Hereafter, the two fastening members 5 may be referred to singly without distinction.

[0016] The outer cover 2 is a component that covers the upper side of the casing 3. The outer cover 2 is hollow and, together with the casing 3, defines the internal space of the submersible pump 1. The outer cover 2 protects internal components (e.g., the motor) from the outside and also constitutes the upper outer shape of the submersible pump 1. The outer cover 2 may be made of, for example, metal or resin, and only needs to have the mechanical strength required for a submersible pump. In the illustrated example, a handle for gripping by the user is provided on the top of the outer cover 2. A drain port 21 is also provided on the top of the outer cover 2. A hose, pipe, etc. (not shown) is connected to the drain port 21.

[0017] The casing 3 is a member that constitutes the outer shape of the lower end of the submersible pump 1. The casing 3 is connected to the lower end of the outer cover 2. In the illustrated example, the casing 3 is circular in plan view. The casing 3 may be made of, for example, resin (urethane). Inside the casing 3, an impeller 6 is arranged. The impeller 6 functions to generate a negative pressure for sucking external liquid by being rotationally driven by a motor in the outer cover 2. The sucked liquid is drained from the drain port 21.

[0018] The casing 3 includes a peripheral edge portion 31, a recessed portion 32, and a groove portion 33. The peripheral edge portion 31 is formed in an annular shape. The peripheral edge portion 31 is located on the outermost side of the casing 3 in the radial direction. The recessed portion 32 and the groove portion 33 are recessed from the peripheral edge portion 31. The groove portion 33 is located between the peripheral edge portion 31 and the recessed portion 32 in the radial direction. The recessed portion 32 and the groove portion 33 may have a shape corresponding to the strainer 4 (for example, circular in plan view). The groove portion 33 is recessed further upward than the recessed portion 32.

[0019] A plurality of side openings 31A are provided at the lower end of the side surface of the peripheral edge portion 31. Each side opening 31A functions as a suction port for introducing liquid from the side in the high water level state H. Each side opening 31A penetrates the side surface of the casing 3 in the radial direction and reaches the strainer 4. The plurality of side openings 31A are spaced apart along the circumferential direction of the casing 3. In the illustrated example, 12 side openings 31A are provided. The 12 side openings 31A are divided into two groups of 6 on the left and right. The 6 side openings 31A in each group are arranged at equal intervals along the circumferential direction of the casing 3. By dispersedly arranging the plurality of side openings 31A in the circumferential direction, it becomes easier to take in the liquid around the submersible pump 1 evenly.

[0020] The recess 32 is provided with a plurality of first fastening holes 32A. Each first fastening hole 32A is a hole through which a corresponding fastening member 5 is inserted and is used to fix the strainer 4 to the casing 3. If the fastening member 5 is a male thread, each first fastening hole 32A may be a female threaded hole into which the fastening member 5 is screwed. The plurality of first fastening holes 32A may be spaced apart from each other in the circumferential direction near the peripheral edge of the casing 3. In the illustrated example, four first fastening holes 32A are provided at a 90° pitch in the circumferential direction. Each first fastening hole 32A penetrates the bottom surface of the casing 3 in the vertical direction.

[0021] Ribs 32B may be provided on the surface of the recess 32. In the illustrated example, four ribs 32B are provided. Multiple ribs 32B protrude downward from the surface of the recess 32 so as to be able to contact the upper surface of the strainer 4. The ribs 32B reduce the contact area between the casing 3 and the strainer 4. The number, shape, size, and arrangement of the ribs 32B are not particularly limited. The ribs 32B may be formed, for example, as straight, curved, ribbed, or intermittent rows of protrusions.

[0022] The strainer 4 is a bottom plate structure located at the bottom of the submersible pump 1. The strainer 4 may be made of metal, for example. The strainer 4 comes into contact with the liquid and the mounting surface during use. In the illustrated example, the strainer 4 is circular in plan view. The strainer 4 introduces liquid into the submersible pump 1 and prevents large foreign objects from entering the interior. The strainer 4 is located below the casing 3. More specifically, the strainer 4 is housed in the recess 32 and the groove 33.

[0023] The strainer 4 includes a bottom plate 41 and side walls 42 rising from the outer circumference of the bottom plate 41. The bottom plate 41 is a disc-shaped member positioned to cover the opening of the recess 32 and constitutes the lower outer surface of the strainer 4. In the illustrated example, the bottom plate 41 is a flat surface. The side walls 42 are positioned to fit into the groove 33. By being positioned along the groove 33, the side walls 42 are guided relative to the casing 3. This makes it easier to house the strainer 4 in the correct position relative to the casing 3.

[0024] The bottom plate 41 is provided with a plurality of bottom suction holes 41A, a plurality of second fastening holes 41B, and a plurality of auxiliary holes 41C. Each of the plurality of bottom suction holes 41A, the plurality of second fastening holes 41B, and the plurality of auxiliary holes 41C penetrates the bottom plate 41 in the vertical direction.

[0025] Each bottom suction hole 41A functions as a suction port for introducing liquid into the casing 3 from the bottom side of the strainer 4. Multiple bottom suction holes 41A contribute to liquid suction in both low water level L and high water level H. In the low water level L, liquid flows mainly into the bottom suction holes 41A from below the bottom plate 41, making it easy to draw up liquid to a low level even when the liquid level drops. Multiple bottom suction holes 41A are distributed across the bottom plate 41. In the illustrated example, multiple bottom suction holes 41A are located in an area closer to the center of the bottom plate 41. This makes it easier to draw liquid from below the bottom plate 41 with relatively little bias. In addition, by providing multiple bottom suction holes 41A, it is easier to suppress the entry of relatively large foreign objects into the interior compared to having a single large opening. As a result, the bottom plate 41 can easily combine the function of introducing liquid and the function of a strainer. The number, shape, size, and arrangement of the bottom suction holes 41A can be appropriately modified in design, taking into consideration the desired suction performance and foreign matter intrusion suppression performance.

[0026] Each second fastening hole 41B is a hole through which a corresponding fastening member 5 is inserted, and is used to fix the strainer 4 to the casing 3. Multiple second fastening holes 41B are provided on the periphery of the casing 3 and may be spaced apart in the circumferential direction of the strainer 4. In the illustrated example, two second fastening holes 41B are provided at a 180° pitch in the circumferential direction. Multiple second fastening holes 41B are arranged to coincide with one of the multiple first fastening holes 32A of the casing 3 at relative positions corresponding to low water level L and high water level H, respectively. In other words, when the strainer 4 is moved relative to the casing 3 with the fastening member 5 removed from the second fastening holes 41B, the second fastening holes 41B coincide with another first fastening hole 32A at a predetermined switching position.

[0027] Each auxiliary hole 41C is used to facilitate the removal of the strainer 4 from the casing 3. Each auxiliary hole 41C is configured to allow a tool (e.g., a screwdriver) or a fingertip to be inserted and engaged. Preferably, each auxiliary hole 41C is positioned so as not to overlap with the multiple first fastening holes 32A in a plan view, regardless of whether the water level is low L or high H. The shape of the auxiliary holes 41C is not particularly limited, but it is preferable that it is shaped in a way that makes it easy to engage the tip of a tool, as shown in the illustrated example. For example, the auxiliary holes 41C may be approximately oval-shaped, or elongated holes with a bulge in the center, in a plan view. Preferably, the auxiliary holes 41C and the other holes (bottom suction holes 41A, second fastening holes 41B) have different external shapes so that the fastening holes and operating holes can be easily distinguished at a glance. Note that the auxiliary holes 41C are holes provided in the strainer 4, and it is not necessary to provide corresponding holes in the casing 3.

[0028] Multiple side suction holes 42A are provided at the upper end of the side wall 42. Each side suction hole 42A is a hole that penetrates the side wall 42 and functions as an opening for introducing liquid into the strainer 4 from the side. Each side suction hole 42A penetrates the side wall 42 radially. The multiple side suction holes 42A are spaced apart along the circumferential direction of the strainer 4. In the illustrated example, 12 side suction holes 42A are provided. The 12 side suction holes 42A are divided into two sets of six, one on the left and one on the right. Each set of six side suction holes 42A is arranged at equal intervals along the circumferential direction of the strainer 4. By distributing the multiple side suction holes 42A circumferentially, it becomes easier to draw in liquid around the submersible pump 1 without bias. As an example, the size of each side suction hole 42A may be larger than each bottom suction hole 41A.

[0029] The strainer 4 is configured to be movable relative to the casing 3. This allows the circumferential positional relationship between each side suction hole 42A and the corresponding side opening 31A to be changed. The strainer 4 can transition between a first position 4A shown in Figure 8 and a second position 4B shown in Figure 9 as its relative position to the casing 3.

[0030] The first position 4A is the position where each side suction hole 42A of the strainer 4 coincides with the corresponding side opening 31A of the casing 3. More specifically, in the first position 4A, each side suction hole 42A and the corresponding side opening 31A overlap in the circumferential direction. As a result, each side suction hole 42A and each side opening 31A are in substantially communication. Here, "substantially communication" means that there are substantially no parts between the side suction holes 42A and the side opening 31A that would obstruct the flow of liquid, and that external liquid can flow into the interior of the casing 3. Therefore, in the first position 4A, the side suction holes 42A of the strainer 4 and the side opening 31A of the casing 3 constitute a side suction path for taking in liquid from the side. In the first position 4A, the two second fastening holes 41B coincide with two of the four first fastening holes 32A.

[0031] In the first position 4A, the liquid can flow into the interior not only through the bottom suction hole 41A but also through the side suction hole 42A and the side opening 31A. Therefore, the submersible pump 1 can secure a relatively large opening area available for suction. Consequently, in the first position 4A, the submersible pump 1 functions in a high water level state H, which is suitable for draining relatively high liquid levels.

[0032] The second position 4B is a position where the lateral suction holes 42A of the strainer 4 do not coincide with the corresponding lateral openings 31A of the casing 3. More specifically, in the second position 4B, the lateral suction holes 42A and the corresponding lateral openings 31A are offset in the circumferential direction. As a result, the lateral suction holes 42A and the lateral openings 31A are not in substantially communication. Here, "not in substantially communication" means that the wall of the casing 3 or strainer 4 is interposed between the lateral suction holes 42A and the lateral openings 31A, so that little or no external liquid flows in from the side into the interior. Therefore, in the second position 4B, liquid inflow from the side is substantially eliminated. In the second position 4B, the two second fastening holes 41B coincide with the two remaining first fastening holes 32A of the four first fastening holes 32A that did not coincide in the first position 4A.

[0033] At the second position 4B, the liquid can flow into the interior mainly through the bottom suction hole 41A. Therefore, the submersible pump 1 is less affected by the inflow of air from the side of the product and can easily draw up the liquid to a relatively low level even when the liquid level drops.

[0034] Thus, in this embodiment, by moving the strainer 4 relative to the casing 3, the alignment and misalignment states of the side suction hole 42A and the side opening 31A can be switched. As a result, the submersible pump 1 can selectively switch between a high water level state H and a low water level state L.

[0035] The fastening member 5 is inserted through the first fastening hole 32A of the casing 3 and the second fastening hole 41B of the strainer 4, which are overlapping each other, thereby fixing the strainer 4 to the casing 3. As a result, the strainer 4 cannot be removed from the casing 3. On the other hand, when the fastening member 5 is removed, the strainer 4 can be removed from the casing 3. In other words, the fastening member 5 not only fixes the strainer 4 but also plays a role in maintaining the switching state between the first position 4A (high water level state H) and the second position 4B (low water level state L). The fastening member 5 may be, for example, a bolt, and its head may be provided so that it is visible from the lower outer surface of the submersible pump 1.

[0036] The operation of the submersible pump 1 according to this invention will be described below.

[0037] Normally, drainage is started when the water level is high, so the submersible pump 1 is set to high water level state H when in use. High water level state H is set by positioning the strainer 4 in the first position 4A and inserting the fastening members 5 through the first fastening hole 32A and the second fastening hole 41B.

[0038] When drainage by the submersible pump 1 has progressed to a certain extent and drainage at a lower water level is required, the system switches between the low water level state L and the high water level state H. First, the bolt cover is removed as needed, and the fastening member 5 is removed from the first fastening hole 32A and the second fastening hole 41B using a tool. This removal can be done smoothly by inserting the tip of the tool into the auxiliary hole 41C. Next, the strainer 4 is moved relative to the casing 3. More specifically, when the strainer 4 is moved to the second position 4B, the second fastening hole 41B aligns with another first fastening hole 32A. The user can transition to the low water level state L by reattaching the fastening member 5 at this alignment position. If necessary, the bolt cover is attached to the fastening member 5.

[0039] Once suction is complete at the low water level L, the submersible pump 1 can be returned to the high water level H by moving the strainer 4 relative to the casing 3 using the same procedure.

[0040] Thus, in this exemplary embodiment, the suction state can be switched by moving the strainer 4 relative to the casing 3 and re-tightening the fastening member 5, without replacing the strainer 4 with another strainer. Therefore, the submersible pump 1 has the advantage of being able to easily handle both low-level and high-level drainage while maintaining good workability on site.

[0041] Furthermore, in high water level conditions H, the submersible pump 1 can utilize the side opening 31A for liquid suction, thus ensuring a relatively large opening area. As a result, it is easier to handle liquids containing relatively large amounts of foreign matter, and clogging is reduced compared to a configuration that uses only the bottom suction hole 41A. On the other hand, in low water level conditions L, the submersible pump 1 can effectively close the side opening 31A. As a result, air inflow from the side is reduced compared to an example where the side suction hole is always open. This makes it easier to reduce residual water and contributes to improving low-water level drainage performance.

[0042] Next, the effects and advantages of this invention will be explained.

[0043] The submersible pump 1 comprises an outer cover 2, a casing 3 connected to the lower end of the outer cover 2, a strainer 4 positioned below the casing 3, and a fastening member 5 that secures the strainer 4 to the casing 3. The strainer 4 is configured to transition between a first position 4A and a second position 4B relative to the casing 3. In the first position 4A, the positions of the side opening 31A and the side suction hole 42A coincide, while in the second position 4B, the positions of the side opening 31A and the side suction hole 42A do not coincide. The first position 4A and the second position 4B are held by the fastening member 5. With this configuration, it is possible to reliably maintain the side opening 31A, which draws in water from the side, in both a closed and exposed state.

[0044] In the submersible pump 1, each side suction port 42A may have dimensions equal to, at least in the height direction, the corresponding side opening 31A. This makes it less likely for vertical misalignment to occur between the two at the first position 4A, and makes it easier to ensure stable communication. In addition, at the first position 4A, it is easier to increase the overlapping area between the side suction port 42A and the side opening 31A, thereby improving the liquid inflow efficiency.

[0045] In the submersible pump 1, the casing 3 is provided with a plurality of first fastening holes 32A, and the bottom plate 41 is provided with a second fastening hole 41B. The plurality of first fastening holes 32A include a first fastening hole 32A that coincides with the position of the second fastening hole 41B at a first position 4A, and another first fastening hole 32A that coincides with the position of the second fastening hole 41B at a second position 4B. With this configuration, the user can reliably maintain the selected state by inserting and fastening the fastening member 5 at the first position 4A or the second position 4B.

[0046] The base plate 41 is provided with auxiliary holes 41C at the first position 4A and the second position 4B, which do not coincide with the positions of the multiple first fastening holes 32A. This configuration improves user operability.

[0047] In the submersible pump 1, the bottom plate 41 may be a flat surface. With this configuration, the submersible pump 1 can stably perform suction from the bottom on the installation surface even when the liquid level is low.

[0048] The number, arrangement, and shape of the side openings 31A, the number, arrangement, and shape of the side suction holes 42A, and the number and arrangement of the fastening members 5 can be changed as needed. The shape of each side opening 31A and side suction hole 42A may be, for example, rectangular or circular oval, and is set so that the necessary inflow is secured in the high water level state H. The number of side suction holes 42A may be the same as the number of side openings 31A, and each side suction hole 42A may have the same or substantially the same shape and dimensions as the corresponding side opening 31A. [Explanation of symbols]

[0049] 1: Submersible pump, 2: Outer cover, 21: Drain port, 3: Casing, 31: Peripheral edge, 31A: Side opening, 32: Recess, 32A: First fastening hole, 32B: Rib, 33: Groove, 4: Strainer, 4A: First position, 4B: Second position, 41: Bottom plate, 41A: Bottom suction hole, 41B: Second fastening hole, 41C: Auxiliary hole, 42: Side wall, 42A: Side suction hole, 5: Fastening member, 6: Impeller, H: High water level state, L: Low water level state

Claims

1. Outer cover and, A casing connected to the lower end of the outer cover, A strainer positioned below the casing, The strainer is provided with a fastening member for fixing it to the casing, The casing includes a side surface with a side opening at its lower end. The strainer includes a bottom plate with a bottom suction hole, and a side wall that includes a side suction hole at its upper end and rises from the outer circumference of the bottom plate. The strainer is configured to transition between a first position and a second position relative to the casing, In the first position, the positions of the side opening and the side suction hole coincide, so that the side suction hole and the side opening are in communication, and the outside and the inside of the casing are connected as a single unit. In the second position, the positions of the side opening and the side suction hole do not coincide, so the side suction hole and the side opening are not in communication, and the inside of the casing is separated from the outside by the side wall. The first and second positions are held by the fastening member, and the submersible pump.

2. The submersible pump according to claim 1, wherein the height of the side suction hole is equal to the height of the side opening.

3. The casing is provided with a plurality of first fastening holes, The bottom plate is provided with a second fastening hole. The submersible pump according to claim 1, wherein the plurality of first fastening holes include a first fastening hole that coincides with the position of the second fastening hole at the first position, and another first fastening hole that coincides with the position of the second fastening hole at the second position.

4. The submersible pump according to claim 3, wherein the bottom plate is provided with auxiliary holes that do not coincide with the positions of the plurality of first fastening holes at the first and second positions.

5. The submersible pump according to any one of claims 1 to 4, wherein the bottom plate is a flat surface.

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