JP2005240624A - Self-priming pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve self-priming performance and achieve less power consumption. <P>SOLUTION: This self-priming pump comprises an impeller 3 having a fluid intake 4 extending from the center to the outside so as to be rotated with the rotation of a motor 1, a casing 5a storing the impeller 3 for converting the dynamic pressure of fluid taken out of the intake 4 of the impeller 3 and injected to the outside into static pressure, a casing cover 5b isolated from the casing 5a via a partition plate 12 and having a first passage 5 for guiding the fluid to the intake 4 of the impeller 3, a nozzle 6 mounted on the casing cover 5b for injecting the fluid with the inner pressure of the fluid in the casing cover 5b, a venturi tube 7 provided in the nozzle 6 for guiding the fluid injected from the nozzle 6 to the intake 4 of the impeller 3 with negative pressure generated, and a second passage 8 connected to a space between the nozzle 6 and the venturi tube 7 and branching from the first passage 5. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a self-priming pump, and more particularly to a technique that is effective when applied to high efficiency and low power consumption of a self-priming pump.

  Conventionally, for example, as disclosed in Japanese Patent Laid-Open No. 10-259791, a spiral pump supplies a reflux water to a blade inlet or a blade outlet so that the blade can efficiently discharge air during self-priming. Or a reflux slit for fluid was provided at the top of the volute case. However, in this case, the size and position of the reflux hole are largely determined depending on the blade diameter, blade tip shape, sealed type or semi-sealed type, and whether the pressure increasing means is a volute type or a guide blade type. There was a limit. In addition, the pumping performance after completion of self-priming by the reflux hole and the reflux slit is that the reflux water flows from the reflux hole, the reflux water circulates, and the amount of reflux increases as the pressure increases. become.

  On the other hand, in the self-priming pump, air is directly sucked into the suction port of the blade during self-suction, and at the same time, water is recirculated to the bypassed passage by the negative pressure generating part (ejector) of the nozzle and the venturi pipe. Since the structure is designed to suck in air, self-priming is performed efficiently. After the self-priming is completed, the valve automatically closes when the pressure of the ejector nozzle exceeds a certain value. A self-priming pump that can ensure the above is realized.

  Hereinafter, conventional techniques will be described.

  5 is a cross-sectional view showing an example of a conventional self-priming pump, FIG. 6 is a front view of the self-priming pump of FIG. 5, FIG. 7 is a front view of a casing attached to the self-priming pump of FIG. It is a front view which shows the partition plate with which the self-priming pump of FIG. 5 was mounted | worn.

  As shown in FIGS. 5 to 8, the self-priming pump is provided with a motor 101 having a rotating shaft 102, and an impeller 103 that rotates integrally with the rotating shaft 102 is attached to the rotating shaft 102. ing. The impeller 103 is stored in a casing 104 that converts the dynamic pressure of water sprayed from the impeller 103 by the rotation of the impeller 103 into a static pressure. A shaft seal 105 is attached between the impeller 103 and the rotating shaft 102 in order to prevent water in the casing 104 from leaking to the rotating shaft 102 of the motor 101.

  The casing 104 includes a volute 108 that guides a gas-liquid two-phase flow to the gas-liquid separation chamber 109 during self-priming, a reflux slit 110 for returning water separated in the gas-liquid separation chamber 109 to the impeller 103, a gas-liquid separation chamber. An opening 111 formed in the partition plate 107 for sending the gas-liquid two-phase flow passing through 109 to the casing cover 106, and a reflux hole 113 for returning the water completely separated in the casing cover 106 to the impeller 103. Is formed.

  A casing cover 106 is provided on the front surface of the casing 104 so as to be separated from the casing 104 by a partition plate 107. The casing cover 106 is provided with a discharge port 112 for discharging air completely separated in the casing cover 106, and a suction port 114 for sucking air in the pipe during self-priming.

  Next, the self-priming operation of the conventional self-priming pump configured as described above will be described.

When the motor 101 is energized with the pump filled with priming water, the rotating shaft 102 starts to rotate. As a result, the impeller 103 fixed to the rotating shaft 102 starts to rotate, and water (gas-liquid two-phase fluid) containing bubbles is ejected from the impeller 103, and along the inner surface of the volute 108, the gas-liquid separation chamber 109. The separated water is returned to the impeller 103 through the reflux slit 110. The gas-liquid two-phase fluid that has not been returned to the impeller 103 flows into the casing cover 106 through the opening 111 of the partition plate 107 and is further separated into air and water. The separated air is discharged from the discharge port 112 of the casing cover 106. It is discharged outside the pump. Part of the water present in the casing cover 106 is returned to the impeller 103 through the reflux hole 113. Furthermore, when the water returned from the reflux slit 110 and the reflux hole 113 returns to the impeller 103, fills the inside of the impeller 103, and the impeller 103 ejects this water, a negative pressure is generated in the impeller 103, and the casing Air is drawn from the suction port 114 of the cover 106. This air is mixed with water by the rotation of the impeller 103 and guided to the gas-liquid separation chamber 109 along the inner surface of the volute. By repeating this operation, self-priming proceeds and water can be pumped.
Japanese Patent Laid-Open No. 10-259791

  As described above, the conventional self-priming pump is provided with a reflux hole or the like in order to supply the reflux water to the blade inlet and the blade outlet so that the blade can efficiently discharge air during self-priming, A reflux slit was provided.

  However, in this case, the size and position of the return hole are largely determined depending on whether the blade diameter, blade tip shape, sealed type or semi-sealed type, and the boosting means is the volute type or the guide blade type, which limits the improvement of self-priming performance. There is.

  Moreover, the pumping performance after completion of self-priming by the reflux hole and the reflux slit is that the reflux water flows from the reflux hole, and the reflux water circulates and the amount of reflux increases as the pressure increases. Become.

  Then, an object of this invention is to provide the self-priming pump which can aim at the improvement of self-priming performance.

  Another object of the present invention is to provide a self-priming pump that can achieve low power consumption.

  In order to solve this problem, the self-priming pump of the present invention is formed with a fluid intake port extending from the center to the outside, and an impeller that rotates integrally with the rotating shaft of the motor, and the impeller is stored. A casing that converts the dynamic pressure of the fluid that is taken in from the intake of the impeller and sprayed outside to static pressure, and is attached separately from the casing via a partition plate, and fluid is supplied to the intake of the impeller A casing cover in which a first passage is formed, a nozzle that is attached to the casing cover and that ejects fluid by the internal pressure of the fluid in the casing cover, and is provided in the nozzle, and the fluid ejected from the nozzle is negative pressure And a second passage branched from the first passage and connected to the space between the nozzle and the venturi tube. It is intended.

In a preferred embodiment of the present invention, the diameter of the nozzle is φ2.5 to φ10, the diameter of the Venturi tube is φ4 to φ11, the inlet angle of the Venturi tube is 15 ° to 40 °, and the tip of the nozzle and the beginning of the straight portion of the Venturi tube The distance of 3 mm to 20 mm, the fluid injection angle and position of the Venturi tube is injected in the direction of 0 to 90 ° with respect to the rotation center axis direction of the impeller and toward the intake port of the impeller, and the tip of the Venturi tube and the blade The distance from the rear shroud surface of the vehicle is 5 mm to 30 mm.

  In a further preferred form of the present invention, guide vanes for converting the dynamic pressure of the gas-liquid phase ejected from the impeller to static pressure are provided on the outer periphery of the impeller, and a start end is formed outside the guide vanes. Thus, a rib that prevents the gas-liquid phase from flowing back to the guide vanes is provided, and a water passage that guides the gas-liquid phase flowing out from the guide vanes out of the casing is formed.

  In a further preferred aspect of the present invention, the nozzle is provided with one or a plurality of rectifying ribs for rectifying the flow of fluid in the nozzle.

  In a further preferred embodiment of the present invention, the partition plate is provided with an opening for communicating the casing and the casing cover and a gas-liquid separation rib for changing the flow direction of the fluid flowing into the casing cover. When the rotation direction of the impeller is counterclockwise with the casing cover facing forward, the angle is 30 ° to 50 ° upward with the casing cover facing forward, the length is 40 mm to 80 mm, and the rotation direction of the impeller is the casing When the cover is faced in the clockwise direction, the angle is 30 ° to 50 ° upward and the length is 40 mm to 80 mm with the casing cover facing the front.

  In a further preferred embodiment of the present invention, the nozzle is detachably attached to the casing cover.

  In a further preferred embodiment of the present invention, a check valve that closes the flow path by pressure fluctuation after completion of self-priming is disposed in the flow path of the fluid toward the nozzle.

  According to the present invention, in addition to the negative pressure generated at the intake port due to the rotation of the impeller, a negative pressure is also generated between the nozzle and the venturi tube, so that the jet is injected from the nozzle through the venturi tube to the intake port of the impeller. The fluidity of the blades improves the watertightness of the blades, and this provides an effective effect that a self-priming pump capable of self-priming in a short time up to a high suction height is obtained.

  Further, according to the present invention, the impeller is always filled with fluid during self-priming, and a high negative pressure is obtained at the contact portion between the nozzle jet and the straight portion of the venturi tube, so that air is efficiently sucked up. Therefore, it is possible to obtain an effective effect that the self-priming time is shortened and noise caused by the gas-liquid phase during self-priming is also reduced.

  Furthermore, according to the present invention, the gas-liquid mixed flow is prevented from continuing to recirculate through the water channel on the outer periphery of the guide blade during self-priming, so that the gas-liquid separation can be performed quickly and the self-priming time can be shortened. An effect is obtained.

  Furthermore, according to the present invention, the generation of vortices in the nozzle is prevented, the generation of noise is suppressed, and the negative pressure when the fluid ejected from the nozzle flows into the venturi tube can be efficiently generated. An effective effect is possible.

  Further, according to the present invention, bubbles do not reach the nozzle entrance during self-priming, and some of the bubbles flowing together with the fluid flowing from the casing through the opening of the partition plate generate vortices by the gas-liquid separation rib. , Air with low specific gravity gathers in the center of the vortex, becomes large bubbles and is efficiently discharged to the discharge side, and the remaining bubbles rise along the gas-liquid separation ribs, making it possible to perform gas-liquid separation efficiently An effective effect is obtained.

  Furthermore, according to the present invention, it is possible to obtain an effective effect that maintenance can be easily performed when foreign matter is clogged in the nozzle or the venturi tube.

  Furthermore, according to the present invention, the pump efficiency is improved by stopping the flow of recirculation of the nozzle, and the effective flow rate can be obtained with low power consumption, and a low noise self-priming pump can be obtained.

  According to a first aspect of the present invention, a fluid intake port extending from the center toward the outside is formed, and an impeller that rotates integrally with a rotating shaft of a motor, an impeller is stored, and the impeller A casing that converts the dynamic pressure of the fluid that is taken in from the intake port and jetted to the outside into a static pressure, and is attached separately from the casing via the partition plate, and the first guides the fluid to the intake port of the impeller A casing cover in which a passage is formed, a nozzle attached to the casing cover and ejecting fluid by the internal pressure of the fluid in the casing cover, and a negative pressure is generated in the fluid ejected from the nozzle. A self-priming pump having a venturi pipe leading to an intake port of an impeller, and a second passage branched from the first passage and connected to a space between the nozzle and the venturi pipe, and the impeller In addition to the negative pressure generated at the intake by rotation, a negative pressure is also generated between the nozzle and the venturi tube, so the fluid that is jetted from the nozzle through the venturi tube to the intake port of the impeller causes the blade to be watertight. Thus, there is an effect that a self-priming pump capable of self-priming in a short time up to a high suction height can be obtained.

  The invention according to claim 2 of the present invention is the invention according to claim 1, wherein the nozzle diameter is φ2.5 to φ10, the venturi pipe diameter is φ4 to φ11, and the venturi pipe inlet angle is 15 ° to 40 °. The distance from the tip of the nozzle to the start of the straight portion of the Venturi tube is 3 mm to 20 mm, the fluid ejection angle and position of the Venturi tube is 0 to 90 ° with respect to the rotation center axis direction of the impeller, and the impeller is incorporated It is a self-priming pump that sprays toward the mouth and the distance from the tip of the Venturi tube to the rear shroud surface of the impeller is 5 mm to 30 mm. During self-priming, the impeller is always filled with fluid, A high negative pressure is obtained at the contact part between the jet and the straight part of the venturi tube, and air can be efficiently sucked up. An effect that noise caused is reduced to.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, a guide vane that converts the dynamic pressure of the gas-liquid phase ejected from the impeller into a static pressure is provided on the outer periphery of the impeller. Provided on the outside of the guide vane is provided with a rib that forms a starting end and prevents the gas-liquid phase from flowing back to the guide vane, and a water passage that guides the gas-liquid phase flowing out from the guide vane to the outside of the casing. It is a self-priming pump that is formed, and it is prevented that the gas-liquid mixed flow continues to recirculate through the water channel on the outer periphery of the guide blade during self-priming, so that gas-liquid separation can be performed quickly and self-priming time can be shortened Has an effect.

  The invention according to claim 4 of the present invention is the invention according to any one of claims 1 to 3, wherein the nozzle is provided with one or a plurality of rectifying ribs for rectifying the flow of fluid in the nozzle. It is a self-priming pump that prevents the generation of vortices in the nozzle and suppresses the generation of noise, and can efficiently generate negative pressure when the fluid ejected from the nozzle flows into the venturi pipe It has the action.

According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the partition plate is provided with an opening for communicating the casing and the casing cover, and is provided in the casing cover. A gas-liquid separation rib is provided to change the flow direction of the inflowing fluid, and the gas-liquid separation rib rises to the right with the casing cover facing forward when the rotation direction of the impeller is counterclockwise with the casing cover facing the front. 30 ° -50 °, length 40mm-80mm, when the impeller rotation direction is clockwise with the casing cover facing forward, the angle is 30 ° -50 ° to the left with the casing cover facing forward, length is 40mm It is a self-priming pump of ˜80 mm, and air bubbles do not reach the nozzle inlet during self-priming and flow with the fluid that has flowed from the casing through the opening of the partition plate. Part of the air vortex is generated by this gas-liquid separation rib, and air with a small specific gravity gathers in the center of the vortex, becomes a large bubble and is efficiently discharged to the discharge side, and the remaining bubble rises along the gas-liquid separation rib. , It has an effect that gas-liquid separation can be performed efficiently.

  The invention according to claim 6 of the present invention is the self-priming pump according to any one of claims 1 to 5, wherein the nozzle is detachably attached to the casing cover, and the nozzle and the venturi tube It has an effect that maintenance can be easily performed when a foreign object is clogged.

  The invention according to claim 7 of the present invention is the invention according to any one of claims 1 to 6, wherein the flow path of the fluid toward the nozzle is blocked by pressure fluctuation after completion of self-priming. This is a self-priming pump with a check valve that stops the flow of the reflux of the nozzle, improving pump efficiency, obtaining a specified flow rate with low power consumption, and obtaining a low-noise self-priming pump. Has an effect.

  Hereinafter, the best mode for carrying out the present invention will be described more specifically with reference to the drawings. Here, in the accompanying drawings, the same reference numerals are given to the same members, and duplicate descriptions are omitted. In addition, since description here is the best form by which this invention is implemented, this invention is not limited to the said form.

  1 is a cross-sectional view showing a self-priming pump according to one embodiment of the present invention, FIG. 2 is a cross-sectional view showing the self-priming pump according to one embodiment of the present invention cut away from a direction orthogonal to FIG. FIG. 3 is an explanatory view showing the structure of the guide vane provided in the self-priming pump according to one embodiment of the present invention, and FIG. 4 is the structure of the nozzle and the venturi tube in the self-priming pump according to one embodiment of the present invention. It is explanatory drawing which shows.

  As shown in FIGS. 1 to 4, the self-priming pump of the present embodiment has an impeller 3 that rotates integrally with the rotating shaft 2 of the motor 1. The impeller 3 is formed with a fluid intake 4 formed so as to spirally extend from the center toward the outside, and is taken out from the intake 4 of the impeller 3 by the rotation of the impeller 3. It is stored in a casing 5a that converts the dynamic pressure of the fluid jetted into the static pressure. A shaft seal is inserted between the casing 5 a and the rotating shaft 2 of the motor 1 to prevent water in the casing 5 a from entering the motor 1.

  A casing cover 5b having a suction port 4a for taking fluid into the pump and a discharge port 15 for letting fluid out of the pump is attached to the front surface of the casing 5a, separated from the casing 5a via a partition plate 11a. ing. The casing cover 5 b is provided with a first passage 5 that guides fluid to the intake 4 of the impeller 3 in a structure that is completely isolated from the discharge port 15.

  In addition, the opening part 12 for flowing water from the casing 5a to the casing cover 5b is formed in the partition plate 11a.

A nozzle 6 that ejects fluid by the internal pressure of the fluid in the casing cover 5b is attached to the casing cover 5b, and a cap 6a is covered at the tip of the nozzle 6. The nozzle 6 and the cap 6a can be easily disassembled by screwing on the front surface, so that maintenance can be easily performed when the nozzle 6 or the venturi tube 7 is clogged with foreign matter.

  The nozzle 6 is provided with one or more rectifying ribs for rectifying the flow of fluid in the nozzle 6. Thereby, generation | occurrence | production of the vortex in the nozzle 6 is prevented, generation | occurrence | production of noise is suppressed, and the negative pressure when the fluid injected from the nozzle 6 flows in into the venturi pipe 7 can be generated efficiently.

  A venturi tube 7 is provided in the nozzle 6 to guide the fluid ejected from the nozzle 6 to the intake 4 of the impeller 3, and negative pressure is generated when the fluid ejected from the nozzle 6 flows into the venturi 7. It has a structure that generates. A second passage 8 of fluid branched from the first passage 5 is connected to the space between the nozzle 6 and the venturi tube 7.

  On the outer periphery of the impeller 3, there are provided guide vanes 9 that convert the dynamic pressure of the gas-liquid phase ejected from the impeller 3 into a static pressure. A water channel 10 for guiding the gas-liquid phase to the outside of the casing 5a is formed. The water channel 10 is provided with a rib 11 that forms the start end of the water channel 10 and prevents the gas-liquid phase from flowing back to the guide vanes 9 in contact with the partition plate 11a. As a result, the gas-liquid mixed flow is prevented from continuing to recirculate in the water channel on the outer periphery of the guide blade 9 during self-priming, and gas-liquid separation can be performed quickly.

  The casing cover 5b is formed with a gas-liquid separation chamber 13 that separates the gas-liquid phase. The gas-liquid separation chamber 13 has a horizontal angle θ and a length L, and is separated from the gas-liquid phase. Liquid separation ribs 14 are arranged.

  A check valve 18 that automatically closes due to pressure fluctuation after completion of self-priming is disposed in the fluid flow path toward the nozzle 6. The check valve 18 includes a ball valve 20 that contacts the valve seat 19 and closes the passage, and a spring 21 that holds the ball valve 20 at a position spaced from the valve seat 19 during self-priming. Thus, the pump efficiency is improved by stopping the recirculation flow of the nozzle 6, a specified flow rate is obtained with low power consumption, and a low noise self-priming pump is obtained.

  Next, the self-priming operation of the self-priming pump of the present invention configured as described above will be described.

  When the motor 1 is energized with the self-priming pump filled with priming water, the rotating shaft 2 starts to rotate and the impeller 3 fixed to the rotating shaft 2 starts to rotate. Then, a negative pressure is generated at the intake 4 of the impeller 3, and air bubbles start to be sucked through the first passage 5. As described above, the first passage 5 is completely isolated from the discharge port 15. Further, the water jetted from the nozzle 6 due to the differential pressure between the internal pressure of the casing cover 5b and the suction pressure of the impeller 3 from the nozzle 6 flows smoothly into the center of the impeller 3 through the Venturi tube 7, and thus higher. Negative pressure is generated. Further, a negative pressure is generated in the second passage 8 which branches from the middle of the first passage 5 and communicates with the space between the nozzle 6 and the venturi tube 7, sucks up bubbles and sends them to the impeller 3.

  Here, as a result of optimizing the shape of the nozzle 6 and the Venturi tube 7 that efficiently generate the negative pressure using the orthogonal table, it is desirable to have the following dimensions.

  4, the diameter of the nozzle 6 is φ2.5 to φ10, the diameter of the Venturi tube 7 is φ4 to φ11, the inlet angle of the Venturi tube 7 is 15 ° to 40 °, the tip of the nozzle 6 and the straight of the Venturi tube 7 The distance to the beginning of the portion 7a is 3 mm to 20 mm, the fluid ejection angle and position of the venturi tube 7 is 0 to 90 ° with respect to the rotation center axis direction of the impeller 3 and toward the intake 4 of the impeller 3. The distance from the tip of the venturi tube 7 and the rear shroud surface of the impeller 3 is 5 mm to 30 mm.

  In this way, the impeller 3 is always filled with fluid during self-priming, and a high negative pressure is obtained at the contact portion between the jet flow of the nozzle 6 and the straight portion 7a of the venturi tube 7, and the air is efficiently discharged. Since it can be sucked up, the self-priming time is shortened and the noise caused by the gas-liquid phase during self-priming is also reduced.

  Now, the impeller 3 rotates to eject water containing bubbles, and the ejected water enters the guide blade 9, the dynamic pressure is converted to static pressure, and then the gas-liquid discharged from the guide blade 9 The two-phase flow flows along the water channel 10 on the outer periphery of the guide blade 9. At this time, the flow exiting the guide vane 9 by the rib 11 for preventing the return to the water channel 10 smoothly flows toward the opening 12 of the partition plate 7 and flows out through the opening 12 to the casing cover 5b side.

  Thereafter, the flow of the fluid is guided to the gas-liquid separation chamber 13 of the casing cover 5b, and a part of the gas-liquid two-phase flow collides with the gas-liquid separation rib 14 to form a vortex and the low specific gravity of the air is the center of the vortex. Are efficiently separated into gas and liquid, and air is discharged from the discharge port 15. Some of the bubbles rise to the water surface along the gas-liquid separation rib 14 and are discharged from the discharge port 15.

  The shape of the gas-liquid separation rib 14 is an important factor related to the self-priming time. The inventor selected the horizontal angle θ and the length L of the gas-liquid separation rib 14 as the shape factor, and conducted an experiment to examine the relationship with the self-priming completion time. From the experimental results, the following specifications were found to be effective for self-priming.

  That is, for example, in the present embodiment, the rotation direction of the impeller 3 is counterclockwise with the casing cover 5b in front, so that the horizontal angle θ of the gas-liquid separation rib 14 increases to the right with the casing cover 5b in front. 30 ° to 50 °, and the length L is in the range of 40 mm to 80 mm. In this way, bubbles do not reach the entrance of the nozzle 6 during self-priming, and some of the bubbles flowing together with the fluid flowing from the casing 5a through the opening 12 of the partition plate 11a are retained by the gas-liquid separation rib 14. A vortex is generated and air having a small specific gravity gathers in the center of the vortex and becomes a large bubble and is efficiently discharged to the discharge side, and the remaining bubble rises along the gas-liquid separation rib 14 and is efficiently gas-liquid separated. By repeating this operation, self-priming progresses and water can be pumped efficiently. After completion of self-priming, the ball valve 20 of the check valve 18 abuts on the valve seat 19 when the internal pressure of the casing cover 5b reaches a certain pressure corresponding to the restoring force of the spring 21, and can stop the recirculation. The self-priming pump with low power consumption and low noise can be realized.

  When the rotation direction of the impeller 3 is clockwise with the casing cover 5b in front, the horizontal angle θ of the gas-liquid separation rib 14 is 30 ° to 50 ° in the upward direction with the casing cover 5b in front, and the length L Is in the range of 40 mm to 80 mm.

  As described above, according to the present invention, a negative pressure is generated between the nozzle 6 and the Venturi tube 7 in addition to the negative pressure generated at the intake port 4 by the rotation of the impeller 3. The water-tightness of the blades is improved by the fluid jetted through the intake port 4 of the impeller 3 through 7, and thus a self-priming pump capable of self-priming in a short time up to a high suction height is obtained.

  The self-priming pump of the present invention is a technique useful for improving self-priming efficiency and reducing power consumption of the pump.

Sectional drawing which shows the self-priming pump which is one embodiment of this invention Sectional drawing which fractures | ruptures and shows the self-priming pump which is one embodiment of this invention from the direction orthogonal to FIG. Explanatory drawing which shows the structure of the guide blade | wing provided in the self-priming pump which is one embodiment of this invention Explanatory drawing which shows the structure of the nozzle and venturi pipe in the self-priming pump which is one embodiment of this invention Sectional drawing which shows an example of the conventional self-priming pump Front view of the self-priming pump of FIG. The front view which shows the casing with which the self-priming pump of FIG. 5 was mounted | worn The front view which shows the partition plate with which the self-priming pump of FIG. 5 was mounted | worn

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Motor 2 Rotating shaft 3 Impeller 4 Intake port 4a Suction port 5 1st channel | path 5a Casing 5b Casing cover 6 Nozzle 6a Cap 7 Venturi pipe 7a Beginning of a straight part 8 2nd channel | path 9 Guide vane 10 Water path 11 Return prevention rib 11a Partition plate 12 Opening portion 13 Gas-liquid separation chamber 14 Gas-liquid separation rib 15 Discharge port 18 Check valve 19 Valve seat 20 Ball valve 21 Spring θ Horizontal angle L Length

Claims (7)

An impeller that is formed with a fluid intake port extending from the center toward the outside and rotates integrally with the rotation shaft of the motor;
A casing for storing the impeller and converting the dynamic pressure of fluid taken from the intake port of the impeller and sprayed to the outside into a static pressure;
A casing cover that is attached separately from the casing via a partition plate, and in which a first passage for guiding fluid to the intake port of the impeller is formed;
A nozzle attached to the casing cover and ejecting fluid by an internal pressure of the fluid in the casing cover;
A Venturi tube provided in the nozzle, which generates a negative pressure for the fluid ejected from the nozzle and guides the fluid to the intake port of the impeller;
A self-priming pump comprising a second passage that is connected to a space between the nozzle and the venturi pipe and branches from the first passage. The diameter of the nozzle is φ2.5 to φ10, the diameter of the venturi tube is φ4 to φ11, the inlet angle of the venturi tube is 15 ° to 40 °, and the distance from the tip of the nozzle to the start of the straight portion of the venturi tube 3 to 20 mm, the fluid injection angle and position of the Venturi tube is 0 to 90 ° with respect to the rotation center axis direction of the impeller and toward the intake port of the impeller, and the tip of the Venturi tube The self-priming pump according to claim 1, wherein the distance from the rear shroud surface of the impeller and the impeller is 5 mm to 30 mm. On the outer periphery of the impeller, there are provided guide vanes that convert the dynamic pressure of the gas-liquid phase ejected from the impeller into a static pressure,
On the outside of the guide vane, a rib is formed that forms a start end and prevents the gas-liquid phase from flowing back to the guide vane,
The self-priming pump according to claim 1 or 2, wherein a water passage for guiding the gas-liquid phase flowing out from the guide vanes to the outside of the casing is formed. The self-priming pump according to any one of claims 1 to 3, wherein the nozzle is provided with one or a plurality of rectifying ribs for rectifying the flow of fluid in the nozzle. The partition plate is provided with an opening for communicating the casing and the casing cover and a gas-liquid separation rib for changing the flow direction of the fluid flowing into the casing cover.
The gas-liquid separation rib is
When the rotation direction of the impeller is counterclockwise with the casing cover facing forward, the angle is 30 ° to 50 ° upward and the length is 40 mm to 80 mm with the casing cover facing forward.
When the rotation direction of the impeller is clockwise with the casing cover facing in front, the angle is 30 ° to 50 ° upward and the length is 40 mm to 80 mm with the casing cover facing in front. Item 5. The self-priming pump according to any one of Items 1 to 4. The self-priming pump according to any one of claims 1 to 5, wherein the nozzle is detachably attached to the casing cover. 7. The check valve according to claim 1, wherein a check valve that closes the flow path by pressure fluctuation after completion of self-priming is disposed in the flow path of the fluid toward the nozzle. Self-priming pump.

Images