JP7588293B2 - pump - Google Patents

Description

The present invention relates to the structure of a pump used to pump water.

Conventionally, this type of pump is known to rotate an impeller connected to the rotating shaft of a motor to draw water in through a suction port in a casing and discharge it from a discharge port (see, for example, Patent Document 1).

The pump is described below with reference to Figure 7.

As shown in FIG. 7, a conventional pump has a pump section 103 having an impeller 102 driven by a motor 101, a casing 104 fixed to the pump section 103 and having a discharge port 105, and a casing flow passage section 106 in the casing 104 that pressurizes water by the rotation of the impeller 102.

In order to achieve this object, a pump according to one embodiment of the present invention comprises an impeller having impeller blades on its outer periphery, a casing forming an impeller flow path around the impeller, and a suction-side flow path and a discharge-side flow path provided in the casing and communicating with the impeller flow path, wherein of the wall surfaces of the suction-side flow path connected to the impeller flow path, the wall surface upstream in the direction of rotation of the impeller is on the outside of the bend in the bent portion of the suction-side flow path, and an extension line of the wall surface upstream in the direction of rotation of the impeller is tangent to a circumference formed by the inner circumference of the impeller blades, and water that flows into the impeller blades from the outer periphery of the impeller blades along the wall surface of the suction-side flow path upstream in the direction of rotation of the impeller is pressurized in the impeller flow path as the impeller rotates and flows out to the discharge-side flow path , thereby achieving the desired object.

Conventionally, the flow paths inside the pump were not smoothly connected at the joints between the flow paths and the rotating part of the impeller (hereafter referred to as the pressure boosting part), which could result in losses and put a load on the impeller. The above losses were unnecessary for the pump to function, and posed the problem of reducing the work efficiency of the pump.

The present invention aims to solve the above-mentioned problems of the conventional pump by reducing unnecessary losses at the junction between the pump flow path and the boost section, thereby providing a pump with improved work efficiency.

To achieve this objective, a pump according to one aspect of the present invention comprises an impeller with impeller blades on its outer periphery, a casing that forms an impeller flow path around the impeller, and a suction-side flow path and a discharge-side flow path that are provided in the casing and communicate with the flow paths, and among the wall surfaces of the suction-side flow path that connect to the impeller flow path, the extension line of the wall surface upstream in the direction of rotation of the impeller is tangent to the circumference formed by the inner circumference of the impeller blades, thereby achieving the desired objective.

According to the present invention, the suction port is provided tangentially to the impeller blade portion, so that the water is smoothly transported into the flow path, unnecessary load on the water flow can be reduced, and a pump with improved work efficiency can be provided.

FIG. 1 is a perspective view showing a pump according to a first embodiment of the present invention; An exploded perspective view of the pump Front cross-sectional view of the casing FIG. 11 is a perspective view showing a pump according to a second embodiment of the present invention; Front cross-sectional view of the casing FIG. 1 is a perspective view showing an impeller according to first and second embodiments of the present invention; Schematic diagram showing a conventional pump

One aspect of the present invention is characterized in that it comprises an impeller having impeller blades on an outer periphery, a casing that forms an impeller flow path around the impeller, and a suction side flow path and a discharge side flow path that are provided in the casing and communicate with the impeller flow path, wherein of the wall surfaces of the suction side flow path that connect to the impeller flow path, the wall surface upstream in the direction of rotation of the impeller is on the outside of the bend in the bend portion of the suction side flow path, and an extension line of the wall surface upstream in the direction of rotation of the impeller is tangent to a circumference formed by the inner circumference of the impeller blades, and water that flows into the impeller blades from the outer periphery of the impeller blades along the wall surface of the suction side flow path upstream in the direction of rotation of the impeller is pressurized in the impeller flow path as the impeller rotates, and flows out to the discharge side flow path .

With this configuration, the suction port is provided tangentially to the impeller blade portion, so water is transported smoothly through the flow path, reducing unnecessary load on the water flow. As a result, it is possible to provide a pump with improved work efficiency.

In addition, the extension line of the wall surface of the discharge-side flow passage that is connected to the impeller flow passage downstream in the direction of rotation of the impeller may be configured to be tangent to the circumference formed by the inner circumference of the impeller blades.

With this configuration, the discharge port is provided in the tangential direction of the impeller blade portion, so the pressurized water is smoothly transported to the discharge port, reducing unnecessary load on the impeller. This makes it possible to provide a pump that reduces the load on the motor and improves work efficiency.

The following describes an embodiment of the present invention with reference to the drawings.

(Embodiment 1)
1, 2, 3 and 6 show an electric pump according to a first embodiment of the present invention.

As shown in Figures 1 and 2, the pump 1 is composed of a motor section having a motor 4, a casing 7 containing an impeller 5, and a casing cover 8. The motor 4 has a motor frame 2 and a rotating shaft 3. The impeller 5 is connected to the rotating shaft 3 of the motor 4 so that it can rotate when the rotating shaft 3 rotates. The casing 7 has a suction port 9 and a discharge port 12, and the flow switch 15 is attached to the discharge port 12 side of the casing 7. The pump 1 may have a cooling fan 31 that cools the motor 4.

As shown in FIG. 3, the casing 7 has an intake port 9 on the upstream side that communicates with the impeller flow passage 6, and an intake port side flow passage 10 that runs from the intake port 9 to the impeller flow passage 6. The casing 7 has an exhaust port 12 on the downstream side that communicates with the impeller flow passage 6, and an exhaust port side flow passage 13 that runs from the impeller flow passage 6 to the exhaust port 12.

As shown in FIG. 6, the impeller 5 has an impeller blade portion 11 and an impeller inner circumference portion 16. The impeller blade portion 11 is a portion on the outer periphery side of the impeller inner circumference portion 16 on which a plurality of blades (vanes) are provided in the circumferential direction. The impeller blade portion 11 has an outer blade portion 19 which is the outer periphery side of the blades, and an inner blade portion 20 which is the inner periphery side of the blades.

In the present embodiment, the suction port side flow passage 10 flows in from the suction port located on the outer periphery of the impeller 5, and the flow passage is shaped so that it bends in the direction of rotation of the impeller. As shown in FIG. 3, in a cross-sectional view taken along a plane that is perpendicular to the rotation axis of the impeller 5 and includes the impeller 5, the suction port side flow passage 10 has a surface that connects to the upstream side of the rotation direction of the impeller 5 (called the discharge port side wall surface 22) and a surface that connects to the downstream side of the rotation direction of the impeller 5. This discharge port side wall surface 22 is on the outside of the bend at the bend of the suction port side flow passage 10. The extension line of the discharge port side wall surface 22 toward the impeller 5 is in contact with the blade inner periphery 20.

With this configuration, when the impeller 5 is rotated by the rotating shaft 3, water 14 is supplied into the casing 7. When the supplied water 14 passes through the impeller flow passage 6, a water flow is generated by the impeller blade portion 11. The water 14 that has become a water flow flows in the following order: the suction port 9, the suction port side flow passage 10, the suction port side impeller portion 17, the impeller flow passage 6, the discharge port side impeller portion 18, the discharge port side flow passage 13, and the discharge port 12. Finally, the water 14 is discharged from the discharge port 12.

Here, the connection between the conventional suction port side flow passage 107 and the suction port side impeller part 108 shown in FIG. 7 was designed to allow water to easily flow into the impeller blade part 109 and the impeller inner circumference 110. In other words, water from the suction port 111 flows into the impeller blade part 109 at an angle close to the radial direction, so it is less likely to receive force from the impeller blade part 109, and as a result, more water flows into the center, i.e., the impeller inner circumference 110. And when water enters the impeller inner circumference 110, less water is transported to the impeller blade part 109, which is supposed to do work, leading to a reduction in the amount of work done by the pump 113.

In addition, if a large amount of water flows into the impeller inner circumference 110, there is a possibility that some water will flow from the suction port side impeller section 108 to the discharge port side impeller section 115 without passing through the impeller flow passage 112. If this happens, the water that would normally be pressurized in the impeller flow passage 112 will be carried to the discharge port side impeller section 115 without being pressurized, making it difficult for the pump 113 to perform its intended function. Furthermore, the water that is carried to the discharge port side impeller section 115 without being pressurized may collide with the water that has been pressurized in the impeller flow passage 112, resulting in losses.

Meanwhile, as described above, in the pump 1 according to the first embodiment of the present invention, the discharge port side wall surface 22 of the suction port side flow passage 10 is connected tangentially to the blade inner circumference 20 of the impeller blade portion 11. This structure allows the water 14 to be smoothly transported from the suction port side flow passage 10 to the impeller blade portion 11, and makes it difficult for the water 14 to be transported to the impeller inner circumference 16. In other words, the water that flows into the suction port side impeller portion 17 along the discharge port side wall surface 22 of the suction port side flow passage 10 receives a force from the blades as it rides on the rotation of the impeller 5. Then, as the impeller 5 rotates, the water is pressurized in the impeller flow passage 6 and flows out to the discharge port side impeller portion 18 and the discharge port side flow passage 13.

With this configuration, the outlet direction of the suction port side flow passage 10 and the rotation direction of the impeller blade section 11 coincide, and the water that flows in is efficiently pressurized by the impeller blade section 11. In this way, it is possible to reduce losses in the flow of the water 14, and provide a pump with improved work efficiency.

(Embodiment 2)
As a second embodiment of the present invention, the configuration of the discharge port side flow path 13 in the casing 7 will be described with reference to Figures 4 and 5. In Figures 4 and 5, the same components as those in the first embodiment are given the same reference numerals, and detailed description thereof will be omitted.

In this embodiment, the discharge port side flow passage 13 communicates with the discharge port 12 from the discharge port side impeller portion 18. As shown in FIG. 5, in a cross-sectional view taken along a plane that is perpendicular to the rotation axis of the impeller 5 and includes the impeller 5, the discharge port side flow passage 13 has a surface that connects to the upstream side of the impeller 5 in the rotation direction and a surface that connects to the downstream side of the impeller 5 in the rotation direction (referred to as the suction port side wall surface 23). The extension line of the suction port side wall surface 23 of the discharge port side flow passage 13 toward the impeller 5 is in contact with the blade inner periphery 20.

Here, in the conventional connection between the discharge port side flow passage 116 and the discharge port side impeller part 115, the water pressurized in the impeller flow passage 112 is not transported from the discharge port side impeller part 115 to the discharge port side flow passage 116, but is easily transported to the suction port side flow passage 107. That is, as shown in FIG. 7, the extension line of the suction port side wall surface 117 of the conventional discharge port side flow passage 116 is arranged to intersect with the impeller inner circumference part 110, so that the water flowing out from the impeller flow passage 112 collides with the suction port side wall surface 117, making it difficult to flow to the discharge port side flow passage 116. Then, at the inlet of the discharge port side flow passage 116, the smooth flow to the discharge port side flow passage 116 is hindered. As a result, the pressurized water is transported to the suction port side flow passage 107. In this way, the pressurized water is difficult to discharge, which leads to a reduction in the workload of the pump 1.

On the other hand, in the pump 1 of the present invention, the suction port side wall surface 23 of the discharge port side flow passage 13 is connected tangentially to the blade inner circumference 20. With this structure, water flowing out of the impeller flow passage 6 does not collide with the suction port side wall surface 23, and flows smoothly into the discharge port side flow passage 13. Therefore, the water 14 is smoothly transported from the impeller blade portion 11 to the discharge port side flow passage 13, and loss in the flow of the water 14 can be reduced. By reducing loss in the water flow, it is possible to provide a pump with improved work efficiency.

In addition to this embodiment, the suction side flow path structure in the first embodiment may also be provided.

The pump according to the present invention has been described above based on the embodiment, but the present invention is not limited to the embodiment. As long as it does not deviate from the spirit of the present invention, various modifications conceivable by a person skilled in the art to this embodiment and forms constructed by combining components of different embodiments are also included within the scope of the present invention.

The pump of the present invention is effective as a pump with high work efficiency because it reduces water loss and reduces the load on the shaft and motor.

REFERENCE SIGNS LIST 1 pump 2 motor frame 3 rotating shaft 4 motor 5 impeller 6 impeller flow passage 7 casing 8 casing cover 9 suction port 10 suction port side flow passage 11 impeller blade section 12 discharge port 13 discharge port side flow passage 14 water 15 flow switch 16 impeller inner circumference 17 suction port side impeller section 18 discharge port side impeller section 19 blade outer circumference 20 blade inner circumference 22 discharge port side wall surface 23 suction port side wall surface 31 cooling fan 101 motor 102 impeller 103 pump section 104 casing 105 discharge port 106 casing flow passage section 107 suction port side flow passage 108 suction port side impeller section 109 impeller blade section 110 impeller inner circumference 111 Suction port 112 Impeller flow passage 113 Pump 115 Discharge port side impeller portion 116 Discharge port side flow passage 117 Suction port side wall surface

Claims (1)

An impeller having impeller blades on its outer periphery;
a casing that defines an impeller flow passage around the impeller;
The casing includes a suction side flow passage and a discharge side flow passage that communicate with the impeller flow passage,
Among the wall surfaces of the suction-side flow passage connected to the impeller flow passage, the wall surface on the upstream side in the rotation direction of the impeller is on the outside of the bend in the bend portion of the suction-side flow passage, and an extension line of the wall surface on the upstream side in the rotation direction of the impeller is tangent to a circumference formed by an inner circumference of the impeller blades,
A pump in which water flows into the impeller blades from the outer periphery of the impeller blades along the wall surface upstream of the impeller rotation direction of the suction side flow passage , is pressurized in the impeller flow passage as the impeller rotates, and flows out into the discharge side flow passage .

Images