JP2018059469A - Self-priming pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a self-priming pump capable of shortening a self-priming time by enhancing discharge efficiency for air in a liquid without using any complicated structure.SOLUTION: The present invention relates to a self-priming pump comprising a casing having an inlet and an outlet for liquid, an impeller installed in the casing, and a drive part for driving and rotating the impeller. The casing comprises a front-side casing defining a suction-side chamber and a rear-side casing defining a discharge-side chamber. The rear-side casing comprises a rear-side impeller casing and a rear-side discharge casing, and the rear-side impeller casing is provided with a discharge hole for taking a fluid in. The impeller has a blade part which extends radially from a base part as the center to take the fluid to a rotation-directional side, and an outer peripheral wall coupling the blade part to form an opening part with the base part, and a partition part is provided which partitions the discharge-side chamber.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a structure of a self-priming pump that can shorten the self-priming time.

  Conventionally, for example, a drive unit, a casing installed on one end side of the drive unit, an impeller rotated by the drive unit, a front casing having a suction port and defining a suction side chamber on the front side of the impeller, and a discharge hole A self-priming pump including a rear casing that defines a discharge side chamber on the rear side of an impeller and a backflow prevention mechanism that prevents a fluid from flowing back from the discharge side chamber to the suction side chamber is known (Patent Document 1). reference).

  And the backflow prevention mechanism is inserted into a groove in a range in which the output shaft does not pass through, for example, an inner wall portion that partitions the impeller and the suction side chamber. During self-priming operation, air is taken into the fluid by the impeller and is pumped to the discharge-side chamber and circulates in the discharge-side chamber, but some fluid leaks from the gap between the output shaft and the casing to the suction-side chamber. A backflow prevention mechanism is provided at the location to reduce leakage. By doing so, the air contained in the fluid is discharged from the discharge port by buoyancy without being pushed back to the suction side chamber.

JP2015-140701A

  However, the self-priming pump having the backflow prevention mechanism has a problem in that the structure is complicated as compared with a normal one and the cost is increased. Even in the case of a self-priming pump having a backflow prevention mechanism, a part of the air that could not be exhausted from the discharge side chamber continues to circulate in the discharge side chamber and is uniformly diffused into the fluid. There was a problem that it was difficult to exhaust air. Further, since the fluid in the discharge side chamber containing a large amount of air flows back from the discharge side chamber to the suction side chamber through the gap between the output shaft and the casing, the suction side chamber is also easily filled with the fluid containing a large amount of air. This was a cause of reducing the air intake efficiency.

  In view of such a conventional problem, the present invention improves the efficiency of discharging air in a fluid without using a complicated structure, and further prevents a fluid containing a large amount of air from flowing back in a self-priming pump. An object of the present invention is to provide a self-priming pump that can shorten the suction time.

  In order to solve the above problems, a self-priming pump according to claim 1 of the present invention includes a casing having a fluid inlet and outlet, an impeller installed in the casing, and an output shaft. A self-priming pump including a drive unit that rotationally drives the impeller through a front casing that defines a suction side chamber on the suction side of the impeller, and a discharge side chamber on the discharge side of the impeller. A rear casing that partitions and forms a rear impeller casing that partitions and forms an impeller side of the discharge side chamber, and a rear discharge casing that partitions and forms a drive unit side, and the rear side The impeller casing is provided with a discharge hole for taking in the fluid flowing from the impeller side into the discharge side chamber, and the impeller radiates around the base. A blade portion that forms a release space for taking in fluid in the direction of rotation, and an outer peripheral wall that connects the tip portions of the blade portion to each other and forms an opening in a predetermined region between the base portion and the blade portion. And a partition for partitioning the discharge side chamber is provided in the discharge side chamber.

  Further, in the self-priming pump according to claim 2 of the present invention, the partitioning portion is configured by a first partitioning portion and a second partitioning portion, and the first partitioning portion is the one of the rear impeller casing. On the discharge side chamber side, it is provided along the axial direction of the output shaft from the through hole through which the output shaft is inserted, to the outer peripheral side, and the second partition portion is on the discharge side chamber side of the rear discharge casing, It is provided along the axial direction of the output shaft from the insertion hole through which the output shaft is inserted, to the outer peripheral side, and the first partition portion and the second partition portion are joined in the discharge side chamber. It is what.

  Further, in the self-priming pump according to claim 3 of the present invention, the partitioning portion is provided on the downstream side of the flow path of the fluid flowing in the circumferential direction from the discharge hole side to the discharge port side in the discharge side chamber. It is characterized by.

  Further, in the self-priming pump according to claim 4 of the present invention, the partitioning portion is provided on the upstream side of the flow path of the fluid flowing in the circumferential direction from the discharge hole side to the discharge port side in the discharge side chamber. It is characterized by.

  In the self-priming pump of the present invention, the efficiency of discharging the air in the fluid in the discharge-side chamber is improved by providing a partition without using a complicated structure, and is included in the fluid that flows backward in the self-priming pump. Since the amount of air that can be reduced can be reduced, the self-priming time can be shortened.

It is a disassembled perspective view of the self-priming pump in the Example of this invention. It is a cross-sectional view of the self-priming pump in the embodiment of the present invention. It is the (a) front perspective view of the front side impeller casing of the self-priming pump in the example of the present invention, and (b) the rear side perspective view. It is the (a) perspective view of the impeller of the self-priming pump in the Example of this invention, (b) The right view. It is a partial cross section left view of the self-priming pump in the Example of this invention. It is the (a) front perspective view of the rear impeller casing of the self-priming pump in the example of the present invention, and (b) the rear perspective view. It is a perspective view of the rear side discharge casing of the self-priming pump in the Example of the present invention. It is a front view of the rear side discharge casing which shows the flow path in the discharge side chamber of the self-priming pump in the past (a) and the embodiment (b) of the present invention.

  Hereinafter, a self-priming pump according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an exploded perspective view of a self-priming pump. FIG. 2 is a cross-sectional view of the self-priming pump. FIG. 3 is a perspective view of the front impeller casing. 4A is a perspective view of the impeller, and FIG. 4B is a right side view thereof. FIG. 5 is a partially sectional left side view. FIG. 6 is a perspective view of the rear impeller casing. FIG. 7 is a perspective view of the rear discharge casing. FIG. 8 is a front view of the rear discharge casing showing the flow path (a) in the discharge side chamber of the conventional self-priming pump and the flow path (b) in the discharge side chamber in the embodiment of the present invention.

  As shown in FIG. 1 and FIG. 2, the self-priming pump has a suction side chamber side flow path and a discharge side chamber side flow path in the casing connected in series. The suction side chamber side in FIG. 4 is the front side, and the discharge side chamber side is the rear side.

  1 and 2, the self-priming pump according to the embodiment of the present invention mainly includes a casing 10 having a fluid suction port 16 and a discharge port 17, and an impeller installed inside the casing 10. 30 and a drive unit 60 that rotationally drives the impeller 30 via the output shaft 61.

  As shown in FIGS. 1 and 2, the casing 10 includes a peripheral wall 15 that connects the front wall 13 and the rear wall 14, and is formed in a hollow, substantially cylindrical shape. Further, the front wall 13 is provided with a suction port 16 that opens outward, and the rear wall 14 is similarly provided with a discharge port 17 that opens outward. In the present embodiment, the suction port 16 and the discharge port 17 open in the same direction, but are not limited thereto.

  An output shaft 61 extending toward the front wall 13 is inserted into the rear wall 14. A drive unit 60 is connected to the output shaft 61, so that an impeller 30 described later is rotatable. Further, a seal member (not shown) is provided between the output shaft 61 and the rear wall 14.

  Further, in the casing 10, the first inner wall 21 through which the output shaft 61 is inserted on the suction port 16 side is installed on the front peripheral wall 15, and the second output shaft 61 is inserted on the discharge port 17 side. An inner wall 41 is installed on the peripheral wall 15 on the rear side. An impeller 30 that is rotatable by an output shaft 61 is installed between the first inner wall 21 and the second inner wall 41. Thus, the inside of the casing 10 is partitioned and formed into a suction side chamber IA from the suction port 16 to the first inner wall 21 and a discharge side chamber DA from the second inner wall 41 to the discharge port 17. Further, a partition portion 19 that partitions the discharge side chamber DA is installed in the discharge side chamber DA.

  In this embodiment, the casing 10 includes a front casing 11 that partitions the suction side chamber IA on the suction side of the impeller 30 and a rear casing 12 that partitions the discharge side chamber DA on the discharge side of the impeller 30. The front casing 11 includes a front suction casing 18 that partitions the suction port 16 side of the suction side chamber IA and a front impeller casing 20 that partitions the impeller 30 side, and the rear casing 12 is an impeller of the discharge side chamber DA. The rear impeller casing 40 that partitions the 30 side and the rear discharge casing 50 that partitions the drive unit 60 side are configured. The casing 10 is configured by connecting them with fixing means such as bolts.

  The front suction casing 18 is closed at the front side by the front wall 13 and opened at the rear side, and the peripheral wall 15 is provided with a suction port 16 that opens outward. Further, the front impeller casing 20 and the rear impeller casing 40 are accommodated so as to sandwich the impeller 30 from the front and rear. The inner diameters of the front impeller casing 20 and the rear impeller casing 40 are formed to be substantially the same as the outer diameter of the impeller 30 so that the impeller 30 can rotate. At this time, in order to improve the frictional force between the fluid and the impeller 30, it is desirable to make the gap between the inner diameters of the casings 30 and 40 and the outer diameter of the impeller 30 minute.

  In addition, the rear discharge casing 50 is closed at the rear side by the rear wall 14 and is opened at the front side, and the peripheral wall 15 is provided with a discharge port 17 that opens outward. Further, an output shaft 61 extending toward the front side is inserted into the rear wall 14, and a drive unit 60 is installed on the output shaft 61 located on the rear side of the rear casing 18.

  As shown in FIGS. 1 and 3, the front impeller casing 20 is provided with a first inner wall 21 on the front side of the impeller 30. In the first inner wall 21, a through hole 22 through which the output shaft 61 is inserted is formed in a substantially central portion, and a suction hole 23 is formed in the vicinity of the output shaft 61. The suction hole 23 is formed in the upper left region of the through hole 22 when viewed from the suction side chamber IA side in order to suck fluid by rotation of the impeller 30. Further, the center position of the suction hole 23 is formed so as to be decentered upward by a predetermined distance from the center position of the through hole 22 and the opening area on the upper side from this center is reduced.

  A spiral water conduit 24 is formed on the end surface of the first inner wall 21 on the suction side chamber IA side so as to be guided toward the suction hole 23 along the flow path generated by the rotation of the impeller 30. The water conduit 24 is formed along the inner diameter of the front impeller casing 20 in the counterclockwise direction from the suction hole 23 and toward the upper side of the through hole 22 when viewed from the suction side chamber IA side.

  The lower water guide path 24 in the suction hole 23 is provided with an opening wall portion 25 that forms a receiving portion 26 to be described later so that the opening region of the suction hole 23 is expanded to the front side. That is, the water conduit 24 is formed so as to gradually become deeper from the opening wall 25 side to the suction hole 23 side in the counterclockwise direction.

  In the present embodiment, the opening wall portion 25 has a vertical wall portion 25a projecting forward from an end surface near the suction hole 23, and connects the front end portion of the vertical wall portion 25a and the inner diameter of the front impeller casing 20 to each other. Thus, the lateral wall portion 25b is provided. As a result, the suction hole 23 has a shape that is greatly opened to the front side, and the receiving portion 26 is formed. Then, the spiral water conduit 24 is formed so as to gradually become deeper from the front end face of the horizontal wall portion 25b forming the receiving portion 26 to the upper side of the counter-clockwise through hole 22.

  A partition wall 27 is provided in the front impeller casing 20 so as to separate a part of the suction hole 23 from the inner diameter of the front impeller casing 20 toward the through hole 22. The partition wall 27 is formed on the rear side of the lateral wall portion 25 b, thereby forming a receiving portion 26 between the lateral wall portion 25 b and the partition wall 27.

  The partition wall 27 is formed at a position facing the outer peripheral wall 35 of the impeller 30, and the lower end portion 27 a of the partition wall 27 is formed at a position substantially equivalent to the upper end portion of the lateral wall portion 25 b. Thereby, it is possible to facilitate the flow of the fluid into the receiving portion 26.

  The lower end 27a of the partition wall is formed in an arc shape so as to be narrow toward the tip and convex downward. Further, the inner edge 27b of the partition wall 27 is formed in an arc shape along the inner edge of the outer peripheral wall 35 of the impeller 30 described later.

  On the end surface of the first inner wall 21 on the impeller 30 side, as shown in FIG. 3 (b), a substantially U-shaped transfer is performed so that the fluid taken in from the suction hole 23 and the receiving portion 26 is transferred while being pressurized. A groove 28 is formed. The transfer groove 28 is formed so that the upper part communicates with the receiving portion 26, and is set so that the groove becomes shallow from the upstream side to the downstream side on the suction hole 23 side in order to efficiently transfer the fluid. The Specifically, the transfer groove 28 is formed such that the upstream side is formed so as to communicate with the receiving portion 26, and a flow path that is set so that the groove gradually becomes shallow toward the downstream side is formed.

  That is, in the first inner wall 21 on the suction side chamber IA side, the opening wall portion 25 that forms the receiving portion 26 is provided at the front side of the end surface of the through hole 22 through which the output shaft 61 is inserted in the substantially central portion. A spiral water conduit 24 is formed so as to be guided counterclockwise from the opening wall 25 toward the suction hole 23 side, and at the position facing an outer peripheral wall 35 of the impeller 30 described later. The partition wall 27 that separates a part of the partition wall is continuously formed. As shown in FIG. 5, the first inner wall 21 formed in this way has the water guide path 24 and the partition wall 27 continuous at a position facing the outer peripheral wall 35 of the impeller 30 as viewed from the suction side chamber IA side. The suction hole 23 is formed at a position facing an opening 32 of the impeller 30 described later.

  The impeller 30 has openings 32 in a plurality of blade portions 31, and in the suction side chamber IA and the discharge side chamber DA arranged in series, takes air into the fluid flowing in from the suction side chamber IA side and moves to the discharge side chamber DA side. It will be sent. Specifically, the impeller 30 extends radially from the base portion 33 and connects the blade portion 31 formed with an open space 34 for taking in fluid in the rotational direction side to the tip portion of the blade portion 31. The outer peripheral wall 35 which forms the opening part 32 in the predetermined area | region between 33 is formed.

  In the present embodiment, as shown in FIG. 4, the impeller 30 includes a plurality of blade portions 31 that extend radially about a base portion 33. A through hole 36 for inserting the output shaft 61 is formed in the base portion 33, and a key groove 37 for connecting the output shaft 61 is formed in the through hole 36.

  The blade portion 31 has a length dimension substantially equal to the width dimension of the base portion 33, is formed in an arc shape so that an open space 34 is formed on the rotation direction side of the impeller 30, and has a predetermined interval. 33 is provided over the entire outer periphery of 33. Further, the impeller 30 is provided with an outer peripheral wall 35 so as to connect adjacent blade portions 31 to each other. The outer peripheral wall 35 is located at a substantially central portion in the width direction of the base portion 33 and is provided so as to bisect the tip end side of the blade portion 31. As a result, an opening 32 is formed in a predetermined region between the base 33 and the outer peripheral wall 35.

  Further, the impeller 30 is inclined in the counter-rotation direction side of the impeller in the same manner as in the prior art, and a first blade (not shown) located on the front edge side of the base portion 33 and a second blade located on the rear edge side of the base portion 33. (Not shown) can be connected to each other so that the opening 32 can be provided in a predetermined region on the base 33 side.

  In the relationship between the suction hole 23 and the partition wall 27 of the first inner wall 21 and the opening 32 of the impeller 30, as shown in FIG. 5, whether the inner arc line of the suction hole 23 matches the outer peripheral line of the base 33, Or it is desirable to set so that it may be located in the outer diameter side rather than an outer periphery line. In addition, it is desirable that at least a part of the outer line of the opening 32 is overlapped at the position where the arc-shaped inner edge 27b of the partition wall 27 is projected.

  As shown in FIGS. 1 and 6, the rear impeller casing 40 is provided with a second inner wall 41 on the rear side of the impeller 30. The second inner wall 41 is formed with a through-hole 42 through which the output shaft 61 is inserted in a substantially central portion, and fluid that flows from the impeller 40 side to a position that is symmetrical to the suction hole 23 of the first inner wall 21. Is provided in the discharge side chamber DA. Further, the center position of the discharge hole 43 is substantially equal to the center position of the through hole 42, and is formed, for example, so as to reduce the upper opening region from the center.

  As shown in FIG. 6A, a substantially U-shaped transfer groove 44 is formed on the end surface of the second inner wall 41 on the suction side chamber IA side to transfer the fluid taken in by the impeller 40 while being pressurized. Is done. Similarly, the transfer groove 44 is formed so as to close the top, and in order to efficiently transfer the fluid that has taken in air, the transfer groove 44 is counterclockwise from one end facing the discharge hole 43 side as viewed from the suction side chamber IA. The groove is set to be shallower toward the other end in the rotation direction.

  On the end surface of the second inner wall 41 on the discharge side chamber DA side, a spiral water conduit 45 is formed as shown in FIG. A first partition 46 is provided on the discharge side chamber DA side of the rear impeller casing 40 along the axial direction of the output shaft 61 from the through hole 42 through which the output shaft 61 is inserted to the outer peripheral side. The first partition 46 is provided on the upper side of the through hole 42 and in the vicinity of the upper edge of the discharge hole 43. In addition, the first partition 46 is formed in a dogleg shape when viewed from the suction side chamber IA side, but may be formed in a linear shape or an arc shape.

  In the relationship between the discharge hole 43 of the second inner wall 41 and the opening 32 of the impeller 30, the inner arc line of the discharge hole 43 coincides with the outer peripheral line of the base 33, or is positioned on the outer diameter side from the outer peripheral line. It is desirable to set so as to.

  As shown in FIG. 7A, the rear discharge casing 50 is formed with a cylindrical insertion hole 51 through which the output shaft 61 is inserted at a substantially central portion. On the discharge side chamber DA side of the rear discharge casing 50, a second partition 52 is provided along the axial direction of the output shaft 61 from the insertion hole 51 through which the output shaft 61 is inserted to the outer peripheral side. The second partition 52 is provided above the insertion hole 51 and in the vicinity of the upper edge of the base of the discharge port 17.

  The second partition 52 is symmetrical to the first partition 46 described above and is formed so as to be able to be joined to the end face of the first partition 46. That is, in the present embodiment, the partition portion 19 is configured by the first partition portion 46 and the second partition portion 52, and the first partition portion 46 and the second partition portion 52 are configured by the rear impeller casing 40. As a result, the rear discharge casing 50 is assembled and joined in the discharge side chamber DA to form the partition portion 19.

  The partition portion 19 is provided to partition the discharge side chamber DA on the downstream side of the flow path of the fluid flowing in the circumferential direction from the discharge hole 43 side to the discharge port 17 side in the discharge side chamber DA. The air in the flowing fluid is guided to the discharge port 17 at the shortest distance. In the present embodiment, the partition portion 19 is provided above the insertion hole 51 and in the vicinity of the upper edge portion of the base of the discharge port 17.

  Moreover, the partition part 19 may be provided in another position in the discharge side chamber DA as long as the air taken in by the impeller 30 can be discharged from the discharge port 17. For example, the inside of the discharge side chamber DA is on the discharge hole 43 side. May be provided on the upstream side of the flow path of the fluid flowing in the circumferential direction from the discharge port 17 side, specifically, near the lower edge portion of the discharge hole 43 provided in the rear impeller casing 40 It may be provided.

  A plurality of partitions 19 may be provided in the discharge side chamber DA, and the downstream side and the upstream side of the flow path of the fluid flowing in the discharge side chamber DA in the circumferential direction from the discharge hole 43 side to the discharge port 17 side. You may provide in both. In this case, for example, on the downstream side of the flow path, it is provided in the vicinity of the upper edge portion of the base of the discharge port 17, and on the upstream side, in the vicinity of the lower edge portion of the discharge hole 43 provided in the rear impeller casing 40. It is desirable to be provided.

  As long as the partition portion 19 can guide the air in the fluid in the discharge side chamber DA to the discharge port 17, the partition portion 19 has a columnar shape other than the plate shape as in the present embodiment, and other shapes having a thickness. Also good. Moreover, the 1st partition part 46 and the 2nd partition part 52 may be asymmetrical shape, as long as the end surfaces are joined within the discharge side chamber DA. Furthermore, although the partition part 19 in a present Example is comprised from 2 members, it may be comprised by 1 member.

  Next, the operation of the self-priming pump will be described below based on FIG. 2 and FIG. The self-priming pump performs a pumping operation that is a normal operation and a self-priming operation from the start to the transition to the pumping operation. In the self-priming operation, when the impeller 30 rotates counterclockwise, a negative pressure is applied to the suction side chamber IA, and the fluid is sucked into the impeller 30. Due to the centrifugal force and frictional force of the impeller 30, the discharge side chamber DA It is sent to the side.

  In the pumping operation, the fluid filled in the casing 10 by the self-priming operation is sent from the suction side chamber IA side to the discharge side chamber DA side by the rotation of the impeller 30.

  In the casing 10, the fluid flowing in from the suction port 23 of the front impeller casing 20 is sent in the outer diameter direction by the front blade portion 31, and then passes between the partition wall 27 and the impeller 30, and then the suction hole. It is fed in the counterclockwise direction from the 23 side to the discharge hole 43 side. At this time, air is taken into the fluid.

  Specifically, the fluid at the end face of the first inner wall 21 on the impeller 30 side is set so that the transfer groove 28 becomes gradually shallower, so that the fluid is pushed out of the transfer groove 28 according to the rotation of the impeller 30 and opened. It is fed to the rear side via the part 32.

  And the fluid in the end surface of the 2nd inner wall 41 in the impeller 30 side from the opening part 32 is sent into the transfer groove 44 of the 2nd inner wall 41 similarly. Then, the fluid in the transfer groove 44 is sent in the counterclockwise direction, and is set so that the transfer groove 44 gradually becomes shallow, so that the fluid is sent while being pressurized and fed into the discharge hole 43.

  The fluid that has flowed into the discharge side chamber DA from the discharge hole 43 flows in the circumferential direction toward the discharge port 17 in the discharge side chamber DA, collides with the partition portion 19, a part is discharged from the discharge port 17, and the rest is discharged from the discharge side chamber DA. Left in. At this time, in the discharge side chamber DA, the fluid into which the air has been taken in is separated into gas and liquid by the partition portion 19, and the air separated from the fluid is discharged from the discharge port 17 by buoyancy. Then, the fluid from which the air remaining in the discharge side chamber DA is discharged flows back from the discharge side chamber DA in the positive pressure state to the suction side chamber IA in the negative pressure state, thereby again passing through the impeller 30 from the suction side chamber IA. The air is taken into the discharge side chamber DA while taking in air.

  In the configuration of the conventional self-priming pump, air contained in the fluid is uniformly diffused while circulating in the discharge side chamber DA in the circumferential direction as shown in FIG. 17 was difficult to be discharged. In such a state, a fluid containing a large amount of air is sent from the discharge side chamber DA having a positive pressure to the suction side chamber IA having a negative pressure, and again sent to the discharge side chamber DA via the impeller 40. It was a factor that lowered the emission efficiency.

  However, in the present embodiment, the partition 19 provided in the vicinity of the flow path connecting the discharge port 17 and the discharge port 17 of the rear impeller casing 40 with the shortest distance before the air diffuses in the discharge side chamber DA. Since air can be discharged from the discharge port 17, the air in the fluid in the discharge side chamber DA can be reduced. As a result, the fluid in the discharge side chamber DA is returned to the suction side chamber IA having a lower pressure, and the air is again taken in by the impeller and sent to the discharge side chamber DA. Therefore, the air discharge efficiency superior to the conventional one is exhibited. And by extension, the self-priming time can be shortened.

  In addition, although the opening wall part 25, the opening part 26, the partition 27, etc. in the front side impeller casing 20 were formed in the 1st inner wall 21, it is not restricted to this. For example, as long as these are formed on the suction side chamber IA side of the casing 10, the installation location is not particularly limited. In the above embodiment, these are formed on the first inner wall 21 in order to simplify the structure of the self-priming pump. The same applies to the second inner wall 41 of the rear impeller casing 40.

DESCRIPTION OF SYMBOLS 10 Casing 11 Front casing 12 Rear casing 16 Suction port 17 Discharge port 19 Partition part 30 Impeller 31 Blade part 32 Opening part 33 Base part 34 Open space 35 Outer wall 40 Rear impeller casing 42 Through-hole 43 Discharge hole 46 First partition part 50 Rear discharge casing 51 Insertion hole 52 Second partition 60 Driving unit 61 Output shaft IA Suction side chamber DA Discharge side chamber

Claims (4)

A casing having a fluid inlet and outlet;
An impeller installed inside the casing;
A self-priming pump comprising a drive unit that rotationally drives the impeller via an output shaft,
The casing includes a front casing that defines a suction side chamber on the suction side of the impeller, and a rear casing that defines a discharge side chamber on the discharge side of the impeller.
The rear casing is composed of a rear impeller casing that partitions the impeller side of the discharge side chamber, and a rear discharge casing that partitions the drive unit side,
The rear impeller casing is provided with a discharge hole for taking in the fluid flowing from the impeller side into the discharge side chamber,
The impeller extends radially around the base, and connects the blade portion formed with a release space for taking in fluid in the rotational direction side and the tip of the blade portion, and in a predetermined region between the base portion. An outer peripheral wall forming an opening,
A self-priming pump characterized in that a partition for partitioning the discharge side chamber is provided in the discharge side chamber. The partition is composed of a first partition and a second partition,
The first partition is provided on the discharge side chamber side of the rear impeller casing from the through hole through which the output shaft is inserted to the outer peripheral side, along the axial direction of the output shaft,
The second partition is provided along the axial direction of the output shaft from the insertion hole through which the output shaft is inserted to the outer peripheral side on the discharge side chamber side of the rear discharge casing.
2. The self-priming pump according to claim 1, wherein the first partition portion and the second partition portion are joined in the discharge side chamber. 3. The self-priming pump according to claim 1, wherein the partition portion is provided on a downstream side of a flow path of a fluid flowing in a circumferential direction from the discharge hole side to the discharge port side in the discharge side chamber. The said partition part is provided in the upstream of the flow path of the fluid which flows through the discharge side chamber in the circumferential direction from the discharge hole side to the discharge port side, The one of Claim 1 to 3 characterized by the above-mentioned. Self-priming pump.

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