JP2001271779A - Horizontal shaft pump with helical blade - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a horizontal shaft pump with a small size, light weight, high pump head, and high efficiency by using a helical blade in an impeller. SOLUTION: In the small horizontal shaft pump, plural helical blades 11 are installed in the circumferential direction of an almost conical hub 11 at equal intervals with a phase slipped in the impeller 9, the outer circumferential tip 11a of each helical blade 11 is extended to the vicinity of a suction port 2 of a casing 1, and a guide blade 5 for flow rectification is installed in a flow passage on the rear side of the helical blade 11. By constituting like this, the pump is made small and light-weight. Water sucked from the tip of the helical blade 1 is accelerated and pressured by the blade surface of each long one piece blade of plural blades extended to the suction port 2 to provide high pump head, vibration of the pump is made small since the balance of a driving shaft 8 is good, and the efficiency of the pump is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a lightweight and compact horizontal shaft pump as compared with a conventional small horizontal shaft centrifugal pump.

[0002]

2. Description of the Related Art Generally, for transferring liquids such as water,
A centrifugal pump (volute pump) is often used because of its simple structure. FIG. 4 shows an example of a conventional small horizontal shaft centrifugal pump. In FIG.
Is a centrifugal pump. One end of a main shaft 21 provided in the centrifugal pump 20 is connected to a drive shaft 23 of an electric motor 22 by a shaft coupling 24. Reference numeral 25 denotes the centrifugal pump 2
This is a common bed for mounting the motor 0 and the motor 22 integrally. Next, the configuration of the volute pump 20 will be described in detail. The main shaft 21 is supported by a bearing 27 provided on a casing 26, and water is prevented from leaking by a shaft sealing device 28. An impeller 29 is fixed to one end of the main shaft 21. The water flowing from the suction port 30 is supplied to the impeller 29
The water which is accelerated and increased in pressure by the outer periphery of the impeller 29 collects in the spiral chamber 31, is rectified in the spiral chamber 31, and is guided to the discharge port 32.

[0003]

In the above-described conventional small-sized horizontal shaft centrifugal pump 20, the water flowing from the suction port 30 is accelerated by an impeller 29, and the velocity energy of the accelerated water is converted into pressure energy. A swirl chamber 31 is provided to guide the discharge port 32 instead of the spiral. The spiral chamber 31 is configured to surround the outer periphery of the impeller 29, so that the outer diameter of the casing 26 is equal to the outer diameter of the impeller 29.
1, the outer diameter of the casing 26 is considerably larger than the outer diameter of the impeller 29, so that the pump itself becomes large and heavy.

The casing 26 is formed integrally with a leg for attaching to the common bed 25 and a discharge port 32.
The direction of the discharge port 32 is fixed, and when installing the pipe, it must be piped to match the position of the discharge port 32. Depending on the installation situation of the pump, several additional curved pipe parts are required As a result, a large pipe resistance was generated.

[0005] The impeller 2 of the small horizontal shaft centrifugal pump 20 described above
9 is cavitation-prone due to its structure, and if driving is continued for a long time in a state in which cavitation has occurred, the impeller 29 is eroded, and the blades may be cracked or broken. This is the cause of shortening the service life.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention employs a plurality of spiral blades for the blades of a small horizontal shaft pump, and the outer peripheral tip of the spiral blade is connected to a suction port of a casing. The helical blade surface was extended and extended to the vicinity. A guide blade is disposed behind the impeller provided with the spiral blade, and a discharge elbow is provided behind the guide blade to discharge water rectified by the guide blade. The discharge elbow is concentrically supported on the drive shaft, and the discharge ports of the discharge elbow are rotatable by shifting the phase of the discharge ports at equal intervals, thereby minimizing the curved pipe portion of the pipe and reducing the pipe resistance on the discharge side. Let it. Also, in order to reduce the weight of the pump, the casing is composed of a suction pipe and a pump casing, and the pump casing is made of cast steel.
The thickness of the suction pipe and the discharge elbow can be reduced by manufacturing the suction pipe and the discharge elbow from steel.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention has a small-sized structure, as described above, which pressurizes and speeds up water flowing from a suction port of a casing with an impeller, rectifies the water inside the casing, and discharges the water from a discharge port. In the horizontal shaft pump, the impeller is provided with a plurality of spiral blades arranged at equal intervals in the circumferential direction of the substantially conical hub, and the outer peripheral tip of the spiral blade extends to near the suction port. An extended impeller was used. Since the spiral wing is formed by a plurality of long single blades whose tip extends to the suction port, water sucked from the tip of the spiral wing is pressurized and accelerated by the twisted long blade surface. And a high head is obtained. Further, since the plurality of spiral blades are arranged at equal intervals around the drive shaft of the pump with a phase shift, the volume efficiency is good and the discharge amount can be increased. In the small horizontal shaft pump of the present invention, the number of spiral blades is 2 to 2 in terms of pump balance, water supply, and head efficiency.
Three is optimal.

In the pump of the present invention, since two or three spiral blades are arranged at equal intervals and shifted in phase, the balance with respect to the drive shaft is improved, and the vibration applied to the pump is extremely small. Although the efficiency is improved, it is difficult to balance the drive shaft with only one spiral blade, and vibration is generated to lower the efficiency of the pump.

A flow guide in the casing behind the impeller is provided with guide vanes for rectification, and the guide vanes convert the velocity energy of the water accelerated and increased by the spiral blades into pressure energy. The guide vanes are also provided with a plurality of guide vanes in the same manner as the spiral vanes, and since these guide vanes are arranged at equal intervals around the drive shaft of the pump,
Very little rectification in a well-balanced manner causes vibrations in the pump. In the small horizontal shaft pump of the present invention, the optimal number of guide vanes is 3 to 4 in terms of rectification efficiency. Since the guide blades are arranged at the rear of the impeller as described above, a spiral chamber for rectification is not required, and the outer diameter of the casing is only the outer diameter of the impeller plus the thickness of the casing, The pump body becomes smaller and lighter.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. First, FIG. 1 is a side view in which a part of a horizontal shaft pump of the present invention is cut. The casing 1 of the horizontal shaft pump has a suction pipe 3 formed in a bowl-shaped divergent shape from the suction port 2 toward the discharge side, and guide vanes for rectifying the water sucked and accelerated by the suction pipe 3 and accelerated. 5 is provided with a pump casing 4. A discharge elbow 6 is detachably provided on the discharge side of the pump casing 4, and the discharge elbow 6 has a discharge port 7. The water rectified by the guide vanes 5 of the pump casing 4 flows into the discharge elbow 6, the direction is changed by 90 degrees by the discharge elbow 6, and the water is discharged from the discharge port 7. Reference numeral 12 denotes a bearing attached to the pump casing 4, which supports the drive shaft 8.

An impeller 9 is fixed to one end of a drive shaft 8 extending through the side wall of the discharge elbow 6 to the suction pipe 3. The impeller 9 includes a substantially conical hub 10 and a plurality of spiral blades 11 arranged at regular intervals in the circumferential direction of the hub 10 with their phases shifted. As shown in FIG. 2, the spiral blade 11 is formed by successively adding blades used for a pump in a spiral shape.
The hub 10 is tapered so that the blade width dimension in the direction perpendicular to the outer peripheral surface of the hub 10 gradually decreases, and its peripheral edge is close to the inner surface of the casing 1 as shown in FIG.
Further, an outer peripheral end portion 11a of the spiral blade 11 passes through the top of the hub 10 and extends to the vicinity of the suction port 2 of the casing 1.

Next, the other end of the drive shaft 8 projects outside the side wall of the discharge elbow 6, and the tip and the output shaft 14 of the electric motor 13 are connected by a shaft coupling 15. Reference numeral 16 denotes a common bed for mounting the horizontal pump and the electric motor 13 integrally. The drive shaft 8 is supported by a bearing 17 at the side wall penetrating portion of the discharge elbow 6. Reference numeral 18 denotes a shaft sealing device provided to prevent liquid leakage from the through portion, and employs either a gland packing system or a mechanical seal system.

The above-described flange 4a on the discharge side of the pump casing 4 and the flange 6a on the inflow side of the discharge elbow 6 are fastened by bolts 19, and these flanges 4a, 6a are formed concentrically with the drive shaft 8. Have been. or,
The center lines of the bolts 19 that fasten the flanges 4a, 6a are also concentric with the drive shaft 8, and are provided at eight locations at 45-degree pitches at equal intervals. 6 rotates left and right. FIG. 3 is a schematic diagram showing the rotation state of the discharge elbow 6, where the position of the discharge port 7 in the horizontal state is 0 degree, and 45 degrees and 90 degrees to the left.
It is possible to rotate 45 degrees and 90 degrees to the right, select the most appropriate position from five positions according to the piping route on the discharge side, and fasten again with bolts 19. . By adjusting the position of the discharge port 7 to the pipe route in this manner, the number of bent pipe portions of the discharge-side pipe is reduced, and the pipe resistance can be reduced.

The pump casing 4 is formed integrally with the guide vanes 5 from a corrosion-resistant cast steel such as stainless steel or nickel-chromium-molybdenum alloy. The suction pipe 3 and the discharge elbow 6 are made of stainless steel, nickel By manufacturing from corrosion resistant steel such as molybdenum alloy,
The thickness of the suction pipe 3 and the discharge elbow 6 can be reduced,
Pump weight can be reduced. Since the suction pipe 3, the pump casing 4, and the discharge elbow 6 are respectively fastened by bolts, disassembly and inspection can be performed easily, and maintenance is easy.

[0015]

The horizontal shaft pump of the present invention uses a plurality of spiral blades for the impeller, and the outer peripheral tip of the spiral blade extends to near the suction port of the casing. And, since the guide blade is provided on the rear side of the spiral wing in place of the spiral chamber for rectifying the suction water, the water sucked from the tips of the plurality of long and wide spiral wings has a long blade surface. Accelerated by
High head is obtained and volume efficiency is good. Also, since the outer diameter of the casing becomes smaller, the pump body becomes smaller and smaller.
Lightweight. And since the discharge port is rotatable, the bent pipe portion of the discharge side pipe is reduced, the pipe resistance can be reduced, and this is a small horizontal shaft pump that can be used for a wide range of uses from process to drainage.

[Brief description of the drawings]

FIG. 1 is a side view in which a part of a horizontal shaft pump according to the present invention is cut.

FIG. 2 is a bottom view showing an arrangement state of a spiral wing according to the present invention.

FIG. 3 is a schematic diagram showing a rotation state of a discharge elbow.

FIG. 4 is a side view in which a part of a conventional small horizontal shaft centrifugal pump is cut.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 casing 2 suction port 3 suction pipe 4 pump casing 5 guide blade 6 discharge elbow 7 discharge port 8 drive shaft 9 impeller 10 hub 11 spiral blade 11a outer peripheral tip

Claims (3)

[Claims] 1. A casing (1) arranged in a horizontal direction.
And a discharge elbow (6) for displacing the water flow direction,
An impeller (9) is attached to one end of a drive shaft (8) extending through the side wall of the discharge elbow (6) to the center of the casing (1).
A plurality of spiral blades (11) are arranged on the impeller (9) at equal intervals in the circumferential direction of the substantially conical hub (10), and are arranged on the impeller (9); The outer peripheral tip (11a) of the spiral blade (11) extends to the vicinity of the suction port (2) of the casing (1).
1) A horizontal shaft pump having spiral wings, wherein a guide vane (5) for rectification is provided in a rear flow path. 2. The discharge elbow (6) described above is detachably disposed on the casing (1), and the inflow side of the discharge elbow (6) is supported concentrically on the drive shaft (8). The discharge port (7) of the discharge elbow (6) is rotatable by shifting the phase at equal intervals within a range of 180 degrees above the horizontal center line of the casing (1). A horizontal axis pump having the spiral wing as described in the above. 3. The suction casing (1) described above is divided into a suction pipe (3) and a pump casing (4), and the suction pipe (3) housing the impeller (9) and the discharge elbow (3). 6) is made of a corrosion-resistant steel material, the pump casing (4) is made of a corrosion-resistant cast steel integrally with the guide vane (5), and the suction pipe (3), the pump casing (4),
The horizontal shaft pump having spiral wings according to claim 1 or 2, wherein the discharge elbows (6) are respectively attached by bolts.