JPH048869A - Impulse hydraulic turbine - Google Patents

Abstract

PURPOSE:To improve the efficiency of a hydraulic turbine, and make the hydraulic turbine compact with simple constitution by providing a rotatable impeller, a nozzle hole directed to the pressure receiving face of the impeller and a water drain passage open toward the rotational axis of the impeller, respectively within an impeller housing chamber having a circular internal surface. CONSTITUTION:In an impeller housing chamber 17 having a circular internal surface, an impeller 19 is so housed as to keep the center line of the chamber 17 as an axis of rotation. Also, a nozzle hole 18 is so provided as to be open to the impeller housing chamber 17 and directed to the pressure receiving face of the impeller 19. Furthermore, a water drain passage 14 is opened toward the rotational axis of the impeller 19 in the impeller housing chamber 17. By positioning the impeller 19 in the chamber 17 without any gap as aforementioned, the volume of the chamber 17 can be made small as far as practicable. Also, a water flow is guided along the internal surface of the chamber 17, and effectively comes in contact with the pressure receiving surface of the impeller 19. In addition, the water drain passage 14 formed only at either direction of the rotational axis of the impeller 19 may be effective enough, thereby making a hydraulic turbine compact. According to the aforesaid construction, the efficiency of the hydraulic turbine can be improved and the compact construction thereof can be attained respectively with simple constitution.

Description

[Detailed description of the invention] [Industrial application field] This invention relates to an impulse type water turbine.

[Conventional technology]

Conventionally, as shown in FIG. 14, in an impulse type water turbine, an impeller 2 having a bowl-shaped pressure receiving part is rotatably supported in a casing 1, and a nozzle is installed at the tip of a penstock pipe 3 through which high-pressure water is guided. 4 is assembled, the jet from the nozzle 4 is applied to the impeller 2 to impart rotational force, and the water that has naturally fallen is discharged from the outlet 5 at the bottom of the casing l.

[Problem to be solved by the invention]

However, in such an impulse type water turbine, a space is required to allow the flowing water to fall naturally, and a nozzle 4 must be attached, which hinders miniaturization. Furthermore, in order to effectively apply the jet stream to the pressure receiving surface of the impeller 2 in order to improve the efficiency of the water turbine, it was necessary to reduce the pitch of the blades and increase the number of blades.

An object of the present invention is to provide an impulse type water turbine that can improve efficiency and downsize the water turbine with a simple configuration.

[Means to solve the problem]

A first invention provides an impeller storage chamber formed in a casing and having a circular inner circumferential surface, an impeller disposed rotatably about a rotation axis in the impeller storage chamber, and the impeller storage chamber. The gist thereof is an impulse type water turbine equipped with a nozzle hole that opens into a chamber and is oriented toward the pressure receiving surface of the impeller, and a water drainage channel that opens in the impeller storage chamber of the casing in the direction of the rotation axis of the impeller. .

A second invention provides the casing in the first invention,
a first member having a recess; a second member that is fitted into the recess and to which high pressure water is applied from the outer peripheral side and has a circular inner peripheral surface; and a second member that is closer to the opening than the second member in the recess and a third member provided so as to be in contact with each other.

In a third aspect of the invention, the impeller in the first aspect has a penetrating portion that penetrates in the direction of the rotation axis on its outer circumference.

A fourth invention is such that the water drainage channel in the first invention opens only in the direction of one rotation axis of the impeller in the impeller storage chamber, and the radial bearing has both axially opposite chambers in the closed impeller storage chamber. The impeller has a through hole in its center extending in the direction of its rotation axis.

[Effect]

In the first invention, the volume of the impeller storage chamber can be minimized by arranging the impellers without gaps in the impeller storage chamber having a circular inner circumferential surface. Also, high-pressure water is ejected from the nozzle hole onto the pressure receiving surface of the impeller, imparting rotational force to the impeller. At this time, the water flow is guided to the inner peripheral surface of the impeller storage chamber and effectively hits the pressure receiving surface of the impeller. Water is then discharged from the water drainage channel in the direction of the rotation axis of the impeller.

In addition to the action of the first invention, the second invention provides that either high pressure water is applied to the second member of the casing and a force that tries to pull the second member out of the recess is applied, or the second member is moved by the third member. Movement will be regulated.

In the third invention, in addition to the effects of the first invention, even if the water in the impeller storage chamber swirls at high speed, the increase in back pressure caused by centrifugal force is removed from the water drainage channel through the penetration part. the result,
The efficiency of the water turbine can be improved by alleviating the force in the thrust direction of the impeller.

In the fourth invention, in addition to the effects of the first invention, when air bubbles are present in the water in the impeller storage chamber partitioned by the impeller, the air bubbles are discharged into the water drainage channel via the communication means. the result,
There are no air bubbles on the sliding surface of the radial bearing with the impeller (
This can improve durability.

[First Embodiment] An embodiment embodying the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of a power generation device using an impulse type water turbine of this embodiment, and FIG. 2 is a sectional view taken along line AA in FIG.

A metal main casing 10 is formed with a recess 11 that opens upward in the drawing, and a hydraulic passage 12 that communicates with the recess 11.

Further, a water drainage channel 14 is formed on the bottom surface of the recess 11 via a circular communication port 13. A cylindrical member 15 made of a polymeric material is disposed within the recess 11, and is fitted with the outer circumference of the lower end of the cylindrical member 15 in full contact with the communication port 13, and a flange 15aIJ<, formed on the outer circumference of the upper end. It is fitted into the recess 11 so as to be in contact with the inner peripheral surface of the recess 11 over the entire circumference. An annular high-pressure chamber 16 that communicates with the water pressure path 12 and has a high pressure is formed around the cylindrical member 15, and an impeller storage chamber 17 having a circular inner peripheral surface is formed inside the cylindrical member 15. has been done. The cylindrical material 15 is provided with four nozzle holes 18, which are opened on the inner circumferential surface of the cylindrical material 15 and are designed to jet high-pressure water in the tangential direction of the circumferential direction of the inner circumferential surface. .

Therefore, the flange portion 15a (large diameter portion) of the cylindrical member 15 is in the recessed portion 11.
High pressure water is applied to the outer periphery of the small diameter portion of the cylindrical member 15 as the cylindrical member 15 is inserted into the recess 11, and a force acting on the cylindrical member 15 to cause it to come out of the recess 11.

Impeller 1 made of polymer material provided in impeller storage chamber 17
9, as shown in FIG. 3, a shaft 20 and a blade portion 21 are integrally formed. The blade portion 21 is provided with seven blades 21a each having a blade surface 21b extending in the radial direction and curved in the axial direction, and the outer diameters of the blades 21a in the axial direction are equal. Further, a disk-shaped back plate 22 is fixed to the upper end portion of the blade 21a of the blade portion 21. The outer diameters of the back plate 22 and the blades 21a are slightly smaller than the inner diameter of the cylindrical member 15. Further, a permanent magnet 23 is fixed to the blade portion 21 above the back plate 22, and this magnet 23 is magnetized alternately with S and N poles in the circumferential direction of the impeller 19.

Note that the number of blades 21a may be other than seven, and
The number of nozzle holes 18 may also be other than four. Also, the 9th
As shown in the figure, in the blade 21a, a curved surface 21C may be provided on the back side of the blade surface 21b.

As shown in FIG. 1, the recess 11 of the main casing 10
A partition member 2 made of a thin stainless steel plate is installed in the opening of the
4 are arranged. This partition member 24 is a cylindrical member 15
The permanent magnet 23 is in contact with the upper surface of the impeller 19 and surrounds the outer periphery of the permanent magnet 23 fixed to the impeller 19 . Further, the lower end of the shaft 20 of the impeller 19 is arranged in a recess 25 formed in the middle of the water drainage channel 14, and the same end is connected to a thrust bearing 26 made of a polymer material and a radial bearing 27 made of a polymer material. It is supported by Furthermore, the upper end of the shaft 20 of the impeller 19 is supported by a partition member 24 via a radial bearing 28. In this way, the impeller 19 is arranged in the impeller storage chamber 17 so that the center line of the same chamber 17 becomes the rotation axis, and furthermore, the impeller 19
It has a structure in which a drain water channel 14 is opened at the lower side in the direction of the rotation axis of the rotor 9.

Further, a yoke 29 is attached to the outer periphery of the partition member 24 with the partition member 24 sandwiched between the screws 30 and the main casing lO.
is fixed. Furthermore, a coil 31 is installed inside the yoke 29.
A coil bobbin 32 wound with is arranged. Note that an O-ring 33 is disposed between the partition member 24 and the main casing 10, and the coil 31 is connected to an external device at a terminal 34.

In this embodiment, the casing is composed of the main casing lO, the cylindrical member 15, and the partition member 24, with the main casing 10 serving as the first member, the cylindrical member 15 serving as the second member, and the partition member 24 serving as the third member. .

Next, the operation of the power generation device using the impulse type water turbine configured as described above will be explained.

The high-pressure water in the high-pressure chamber 16 is discharged as a jet onto the inner surface side (impeller side) of the low-pressure cylindrical member 15 through the nozzle hole 18 . The jet flows in from the circumferential tangential direction of the cylindrical member 15 and hits the pressure receiving surface of the impeller 19 while flowing along the inner surface of the cylindrical member 15. At this time, rotational force is applied to the impeller 19 without generating a radial velocity component in the impeller 19. That is, since the jet stream from the nozzle hole 18 travels along the inner surface of the cylindrical member 15, the jet stream tends to hit the pressure receiving surface of the impeller 19.

The water after hitting the impeller 19 is drained from the water drain channel 1.
It is discharged from 4.

Further, as the impeller 19 rotates, the permanent magnet 23 rotates, and the flow of magnetic flux transmitted from the permanent magnet 23 to the yoke 29 changes, and current flows through the coil 31 in a direction that prevents this change, thereby generating power.

As described above, in this embodiment, the impeller 19 is arranged in the impeller storage chamber 17 having a circular inner circumferential surface so that the center line of the chamber 17 becomes the rotation axis, and the impeller 19 is opened to the impeller storage chamber 17. A nozzle hole 18 is provided that faces the pressure receiving surface of the impeller 19, and a water drainage channel 14 is opened in the impeller storage chamber 17 in the direction of the rotation axis of the impeller 19. As a result, the volume of the impeller storage chamber 17 can be made as small as possible by arranging the impeller 19 without gaps in the impeller storage chamber 17 having a circular inner peripheral surface. Further, the water flow is guided to the inner peripheral surface of the impeller storage chamber 17 and effectively hits the pressure receiving surface of the impeller 19. Furthermore, since it is only necessary to form the drain water channel 14 on one side of the impeller 19 in the direction of the rotation axis, the size of the impeller 19 can be reduced. In this way, efficiency can be improved and downsized with a simple configuration.

Further, the casing includes a main casing 10 (first member) having a recess 11, and a cylindrical member 15 (second member) having a circular inner peripheral surface that is fitted into the recess 11 and to which high pressure water is applied from the outer peripheral side. A partition member 2 provided in contact with the cylindrical member 15 on the opening side of the cylindrical member 15 in the recess 11
4 (third member). As a result, the cylindrical material I
High-pressure water is applied to the cylindrical member 5 , and a force is applied to the cylindrical member 15 to try to remove it from the recess 11 , but the movement of the cylindrical member 15 is restricted by the partition member 24 . In other words, the cylindrical member 15 moves upward in FIG. 1 due to the water pressure in the high pressure chamber 16, and the relative positions of the nozzle hole 18 and the impeller 19 in the axial direction may be different from when they are assembled. , the partition member 24 is brought into contact with the cylindrical member 15 from above in FIG.
By fixing the partition member 24 to the main casing 10 at 0, the nozzle hole 18 and the impeller 19 can be positioned in the axial direction and their relative positional dimensions can be maintained in a simple manner.

Furthermore, with regard to the nozzle, conventional equipment requires a minimum number of nozzle components such as a penstock, a nozzle, and parts to fix them. As a result, the number of parts increases, making it difficult to reduce the cost of small impulse water turbines. However, in this embodiment, the cylindrical material 15 serves as both the nozzle and the wall of the penstock, which greatly reduces the number of parts. can.

[Second Embodiment] Next, a second embodiment corresponding to the third invention will be described. This embodiment is the same as the first embodiment except for the shape of the impeller.

As shown in FIG. 4, a penetration part 35 is provided at the peripheral edge of the back plate 22 that restricts the flow of the jet flow, and the penetration part 35 connects the impeller storage chamber 17 divided by the impeller 36 and the water drainage channel 14. 3
It communicates via 5.

Here, the impeller storage chamber 17 and the drain water channel 14 constitute axially opposite chambers, and the through portion 35 constitutes a communication means.

In this way, even if the water in the impeller storage chamber 17 divided by the impeller 36 swirls at high speed, the increase in back pressure caused by centrifugal force can be avoided through the penetration part 35 formed on the outer periphery of the impeller 36. The water can be drained into the drainage channel 14, and the force in the thrust direction of the impeller 36 can be alleviated, thereby improving the efficiency of the water turbine.

As an application example of this second embodiment, the back plate 22 of the impeller may not be used, as shown in FIG. In this case, the thrust force can be reduced and the configuration can be simplified. Furthermore, the penetration portion 35 at the impeller peripheral edge is secured to be larger, and the thrust force can be suppressed more effectively.

[Third Example] Next, a third example corresponding to the fourth invention will be described. This embodiment differs from the first embodiment in that the impeller is of a horizontal type and the bearing structure of the impeller is changed.

As shown in FIG. 6, the shaft 20 of the impeller 37 is arranged horizontally, so that the impeller 37 is of a horizontal type. Further, as shown in FIG. 7, a through hole 39 is provided in the radial bearing 38 that supports one shaft 20 of the impeller 37.
It extends in the direction of the rotation axis. Further, as shown in FIG. 8, the blade portion 37a of the impeller 37 has a through hole 40 extending in the direction of the rotation axis of the impeller 37 near the center thereof.

In the impulse type water turbine configured in this manner, the pressure decreases toward the center of the impeller 37 due to swirling of the water as the impeller 37 rotates, and air bubbles occur to the left of the left end of the blade portion 37a in FIG. is discharged from the through holes 39 and 40 into the drain water channel 14. That is, when assembling the same water turbine, there are times when air bubbles are accumulated to the left of the radial bearing 38 or air bubbles supplied by the water flow are accumulated to the left of the impeller 37.
The bubbles can be expelled.

As a result, if there are air bubbles on the sliding surface of the shaft 20 of the radial bearing 38, there is a risk that wear particles will be unevenly present, leading to a decrease in durability. The durability of the bearing 38 portion can be improved. Also, by making the impeller 37 horizontally placed, it is possible to reduce the accumulation of air bubbles.

[Fourth Example] Next, a fourth example will be described. This embodiment is the same as the first embodiment except for the shape of the impeller.

As shown in FIG. 10.11, the blade portion 21 of the impeller 19
An annular ring portion 41 is integrally formed at the bottom of the holder. This ring portion 41 has a plate shape and has a structure extending in the direction of the rotation axis of the impeller 19. The outer peripheral surface of the ring portion 41 has a slightly smaller diameter than the inner peripheral surface of the cylindrical member 15. This ring portion 41 is arranged below the opening of the nozzle hole 18 of the cylindrical member 15.

Further, the lower surface portion of the back plate 42 of the impeller 19 is formed into a slanted surface 43 such that the diameter becomes smaller in the lower part.

This slanted surface 43 is located slightly above the opening of the nozzle hole 18.

Note that the blade portion 21 and the back plate 42 of the impeller 19 may be separate or integrated. Further, the slanted surface 43 of the back plate 42 may extend linearly or curvedly.

Furthermore, the back plate 42 of the impeller 19 has a through portion 44 on the outer periphery.
is formed.

In the impulse water turbine formed in this way,
The ring portion 41 reduces the water flow flowing into the impeller storage chamber 17 from flowing into the gap 45 between the impeller 19 and the impeller storage chamber 17 before it effectively acts on the impeller 19.
By effectively operating the impeller 19, the efficiency of the water turbine can be improved. In addition, an inclined surface 43 formed on the back plate 42
As a result, the stagnation area of the water flow flowing into the impeller storage chamber 17 is reduced, and the direction of the water flow ejected from the nozzle hole 18 is efficiently converted to the direction of the rotation axis within the impeller 19, thereby improving the efficiency of the water turbine. .

That is, the impeller 19 is arranged rotatably around its rotation axis in the impeller storage chamber 17 having a circular inner peripheral surface, and the nozzle hole 18 is opened in the impeller storage chamber 17 to form a pressure receiving surface of the impeller 19. In an impulse type water turbine in which the water drainage channel 14 is opened in the direction of the rotational axis of the impeller 19 in the impeller storage chamber 17, the outer circumferential portion of the impeller 19 is oriented in the direction of the water flow from the nozzle hole 18. By providing the annular ring portion 41, efficiency can be improved.

Further, an impeller 19 is placed in an impeller storage chamber 17 having a circular inner peripheral surface.
is arranged rotatably around its rotation axis, and the nozzle hole 18
is opened into the impeller storage chamber 17 to direct the pressure receiving surface of the impeller 19, and the water drainage channel 14 is opened into the impeller storage chamber 17.
In the impulse type water turbine having an opening in the direction of one rotation axis of the impeller 19, the nozzle hole 1 in the back plate 42 of the impeller 19
By forming an inclined surface 43 that is inclined in the radial direction in a portion close to the point 8, efficiency can be improved.

As an application of this embodiment, as shown in FIG. 12, a ring portion 41 may be provided without providing a back plate. In this case, since there is no back plate, the configuration can be simplified.

Alternatively, as shown in FIG. 13, the diagonal portion 43 may be provided on the back plate 42 without providing the link portion.

〔Effect of the invention〕

As described in detail above, according to the present invention, an excellent effect of improving efficiency and downsizing can be achieved with a simple configuration.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a power generation device using an impulse water turbine of the first embodiment, Fig. 2 is a cross-sectional view taken along line A-A in Fig. 1, Fig. 3 is a perspective view of the impeller, and Fig. 4 is a Perspective view of the impeller of the second embodiment, No. 5
The figure is a perspective view of the impeller of the applied example of the second embodiment, FIG.
The figure is a sectional view taken along line B-B in Fig. 6, Fig. 8 is a perspective view of the impeller of the third embodiment, Fig. 9 is a perspective view of the impeller of the applied example of the first embodiment, and Fig. 10 is the impeller of the third embodiment. FIG. 11 is a cross-sectional view of a power generation device using an impulse-type water turbine according to the fourth embodiment, FIG. 11 is a perspective view of the impulse-type water turbine, and FIG.
FIG. 13 is a perspective view of an impeller as an applied example of the fourth embodiment, FIG. 14 is a sectional view of a conventional impulse type water turbine. 10 is a main casing (first member), 11 is a recess, 1
4 is a drainage channel, 15 is a cylindrical member (second member), 17 is an impeller storage chamber, 18 is a nozzle hole, 19 is an impeller, 24 is a partition member (third member), 35 is a penetration part, and 37 is a An impeller, 38 a radial bearing, 39 a through hole, and 40 a through hole. Patent applicant Nippondenso Co., Ltd. Agent Patent attorney On 1) Hironobu (and 1 other person) 35.
・・Gokuza Figure 9 Figure 5

Claims (1)

[Scope of Claims] 1. An impeller storage chamber formed in a casing and having a circular inner peripheral surface; an impeller disposed in the impeller storage chamber so as to be rotatable about a rotation axis; and the impeller. An impulse characterized by comprising: a nozzle hole that opens into the vehicle storage chamber and is oriented toward the pressure receiving surface of the impeller; and a water drainage channel that opens in the impeller storage chamber of the casing in the direction of the rotation axis of the impeller. Type water wheel. 2. The casing includes a first member having a recess, a second member that is fitted into the recess and to which high pressure water is applied from the outer peripheral side and has a circular inner peripheral surface, and a second member that is closer to the opening than the second member in the recess. A third member provided so as to be in contact with the second member.
The impulse type water turbine according to claim 1, which comprises a member. 3. The impulse type water turbine according to claim 1, wherein the impeller has a penetrating portion extending in the direction of the rotation axis on its outer circumference. 4. The water drainage waterway opens only in the direction of one rotational axis of the impeller in the impeller storage chamber, and has communication means for communicating both chambers in the axial direction of the radial bearing on the side of the closed impeller storage chamber, The impulse type water turbine according to claim 1, wherein the impeller has a through hole in the center thereof extending in the direction of its rotation axis.