JPS6238891A - Regenerative pump device - Google Patents

Abstract

PURPOSE:To reduce pressure imbalance in radial direction by arranging the starting end of a first stage flow passage and the starting end of a second stage flow passage opposite to each other and the finish end of the first stage flow passage and the finish end of the second stage flow passage opposite to each other. CONSTITUTION:In a regenerative pump device, the starting end 10 of a first stage flow passage and the starting end 15 of a second stage flow passage are arranged to be located, when seen from the center of an impeller 3, substantially 180 deg. opposite to each other. And the finish end 12 of the first stage flow passage and the finish end 16 of the second stage flow passage are located, when seen from the center of the impeller 3, 180 deg. opposite to each other. Accordingly, there is no possibility of large radial pressing force acting on the impeller.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention has an impeller in the form of a regenerative pump, and the impeller controls the pressure of the fluid through at least two channels, a first-stage channel and a second-stage channel. This invention relates to a type of pump device that increases the amount of water and reduces the radial pressure acting on the impeller to improve pump performance.

Such a regeneration pump device is used, for example, to supply fuel to an automobile engine.
It can also be used for various other purposes.

(Prior art) As a pump device of this type, Japanese Patent Application Laid-Open No. 57-206795
There is something disclosed in the publication No. In this pump device, when one impeller having a large number of blade grooves on the circumferential surface of a disk rotates, the pressure of the fluid is increased in the first stage flow path, and then the fluid is transferred to the second stage flow path. The fluid is pressurized.

In this pump, fluid enters the pump chamber from the suction port, passes through the starting end of the first-stage flow path, reaches the end of the first-stage flow path, and is introduced into the starting end of the second-stage flow path, and then The fluid reaches the end of the second stage flow path and is further discharged to the discharge port.

In this known pump device, the suction port is present near the starting end of the first stage flow path, but the position of this suction port and the starting end of the second stage flow path are extremely close to each other. Furthermore, the terminal end of the first stage flow path and the discharge port are also arranged in positions extremely close to each other.

Such a pump device has the drawback that the radial pressure acting on the impeller increases, and the frictional force between the impeller and the wall of the pump chamber around the impeller increases, resulting in a large power loss.

[Problem that the invention seeks to solve]

That is, in the conventional pump device described above, the pressure of the fluid flowing through the first stage flow path and the second stage flow path causes non-uniformity in the radial pressure on the impeller, and this non-uniformity causes the pressure between the impeller and the pump chamber to increase. Alternatively, the frictional force between the impeller and the rotating shaft that drives the impeller increases, resulting in power loss. Therefore, it is an object of the present invention to provide a regeneration pump device with less radial pressure imbalance.

[Structure of the invention]

For this reason, in the present invention, in the regeneration pump device,
The starting end of the first stage flow path (10) and the starting end of the second stage flow path (15)
and are arranged in substantially 180 degrees opposite directions when viewed from the center of the impeller (3), that is, so as to face each other. Further, the end (12) of the first stage flow path and the end (16) of the second stage flow path are arranged so that they are substantially 180 degrees opposite to each other when viewed from the center of the impeller (3), that is, they face each other. This is what was placed.

The first stage flow path and the second stage flow path are connected through a connecting passage (13).
This connected il path (13) was composed of the following: That is, the terminal end (12) of the first stage flow path
a first stage side connection flow path (1B) connecting the impeller and the communication hole (2) in the center of the impeller, and the communication hole (2), and
Connecting passage (13) from the second stage side connecting passage (19) connecting the starting end (15) of the second stage side connecting passage and the communication hole (2)
was formed.

In other words, in a device in which the fluid passes through the first stage flow path, reaches the communication hole in the center of the impeller, and is further connected to the second stage flow path, the starting end of the first stage flow path and the second stage flow path are connected to each other. The starting ends of the channels are opposed to each other, and the terminal ends of the first-stage channels and the terminal ends of the second-stage channels are opposed to each other.

[For production]

As a result, the distribution of the radial pressure of the fluid acting on the outer circumference of the impeller is as follows. In other words, when the pressure distribution is taken over 360 degrees around the impeller's outer circumference, that is, when the outer circumference of the impeller near the suction port is set at an angle of 0 degrees and the impeller rotates once, that is, when the end point of 360 degrees is reached, the first In the stage flow path, the pressure is increased from the suction port and the first
It reaches the end point of the stage flow path, and at that end point, the total discharge pressure P decreases to approximately 1/
The voltage is boosted by 2. Further, it passes through the second stage flow path to the discharge port, and approaches the total discharge pressure P described above.

In such a pressure distribution, the radial pressure acting on the impeller is the average pressure of the first stage flow path pressure and the second stage flow path pressure at the outer periphery of the impeller. That is, the pressure acting on a specific portion of the impeller's outer periphery is the average pressure of the pressure in the first stage flow path and the pressure in the second stage flow path acting on the specific portion of the impeller. When this pressure is applied, the radial pressure acting on the impeller is the average pressure on this particular part and the average pressure acting on another part of the impeller on the opposite side, that is, 180 degrees away. It can be said that the pressure is caused by the difference between

That is, although a pressure distribution occurs on the circumferential surface of the impeller due to each flow path, the harmful radial pressing force acting on the impeller can be said to be generated by the difference in average pressure that occurs at portions separated by 180 degrees.

However, with the above-described structure, the distribution of the difference in average pressure acting on the impeller outer circumferential portions separated by 180 degrees becomes extremely small, and the impeller rotates efficiently within the pump chamber with little power loss.

〔Effect of the invention〕

As described above, in the present invention, since a large radial pressing force is not applied to the impeller, the friction loss acting on the impeller is reduced, and the efficiency of the regenerative pump device can be improved. In other words, the flow rate can be increased at the same discharge pressure, making it possible to provide a compact and high-performance regeneration pump device.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

1 to 4 show a first embodiment, and FIGS. 5 and 6 show the top and bottom planar shapes of the impeller of the first embodiment. 7 and 8 show the characteristics of the first embodiment and the conventional pump device, and FIG. 9 is a graph showing the change in efficiency between the pump device of the first embodiment and the conventional pump device. be.

In FIG. 1, reference numeral 1 denotes blade grooves, which are provided in large numbers on the outer peripheral surface of the impeller 3. 2 is a communication hole formed in the center of the impeller 3. 4 is a rotating shaft partially inserted into the communication hole 2; 5 is a pump case that is connected to the impeller 3;
It surrounds the pump case 5 and forms a pump chamber within the pump case 5. Reference numeral 7 denotes a first stage flow path connected to the suction port 11, and forms a substantially C-shaped flow path as a whole.

Further, 8 is a second stage flow path, which is connected to the first stage flow path via a connecting passage 13, and this also forms a C-shaped flow path as a whole.

FIG. 2 and FIG. 4 show the first stage flow path 7 and the second stage flow path 8 described above.
It also shows the planar shape of a connecting passage 13 that connects these. In FIGS. 2 and 4, 9 is a partition wall portion, and 10 is a starting end of the first stage flow path. and 1
2 is the end of the first stage flow path, 15 is the start end of the second stage flow path, 16
is the terminal end of the second stage flow path and is connected to the discharge port 17.

Reference numeral 18 in FIG. 2 is the first-stage side connection flow path, and reference numeral 19 in FIG. 4 is the second-stage side connection flow path, which are connected to the aforementioned connection path
It forms the main part of

In FIG. 1, the pump case 5 consists of the following three components. That is, 20 is an inlet side housing, and the suction port 11 is integrally provided. A side housing 522 having a ring-shaped wall 21 is an outlet side housing. The impeller 3 is surrounded by a pump case 5 consisting of an inlet housing 20, a side housing 21, and an outlet housing 22.

Reference numeral 23 in FIG. 1 is an impeller recess, which is a component inside the communication hole 2. 24 is a claw type joint, and the impeller recess 2
It is inserted in 3. Reference numeral 25 denotes an impeller thin wall portion formed adjacent to the four impeller portions 23. A through hole 26 is formed in the center of this impeller thin wall portion, and a plurality of joint insertion holes 27 are formed around the through hole 26. It is provided.

This situation is clear in FIG. That is, a through hole 26 is formed in the center of the impeller, and four joint insertion holes 27 are present around the through hole 26.

Note that FIG. 5 is a plan view seen from above in FIG. 1, and the four impeller parts 23 are not visible. Reference numeral 28 denotes an alignment bearing, which supports the rotating shaft 4 .

A bearing holding plate 29 is made of a resilient metal plate and supports the alignment bearing 28. The bearing holding plate 29 is provided with a plurality of holes through which fluid passes.

30 is an armature core of the motor, 31 is a rotor, and 32 is a cylindrical housing, which forms a yoke of the motor.

33 is a magnet forming the field of the motor, 34 is a commutator,
35 is a brush provided so as to be in sliding contact with the commutator; 36
is a discharge side housing, which is molded from resin and is held within the aforementioned cylindrical housing 32. 37 is a check valve, and 3B is a discharge pipe.

Next, regarding the detailed structure around the impeller, an inlet side housing 20 forming a pump case 5 is provided at the upper part of the impeller 3, and a center recess 39 is formed in the center of the inlet side housing 20. The inlet housing 20 and the adjacent side housing 21 are positioned by positioning pins 40. The outlet side housing 22 is a part of the pump case that supports the aforementioned bearing holding plate 29 and the alignment bearing 28, and the outlet side housing 22 and the side housing 2I are also positioned by a positioning pin 40.

In FIG. 1, the lower side and the upper side of the impeller 3, that is, the back side and the front side of the impeller 3, communicate with each other through the impeller recess 23 and the through hole 26. Further, the impeller recess 23 communicates with each other via a gap between the joint insertion hole 27 and the distal end claw 42 of the joint. That is, there is a communication hole 2 in the center of the impeller 3, and the communication hole 2 allows the front and back sides of the impeller to communicate with each other. It is made up of.゛The operation will be explained in the above configuration.

When power is supplied to the brushes 35 by the battery power source, current flows to the rotor 31 via the commutator 34, causing the motor to rotate. Then, the rotating shaft 4 rotates, and the claw-shaped joint 24 integrally connected to the rotating shaft 4 rotates. Since the tip claw 42 of the claw joint 24 engages with the joint insertion hole 27 formed in the impeller thin wall portion 25, the impeller 3 rotates when the claw joint 24 rotates. Since the circumferential surface of the impeller 3 faces the pump case 5 with a slight clearance, the impeller rotates within the pump case 5.

Since a large number of blade grooves 1 having a closed blade type structure are provided on the circumferential surface of the impeller, the impeller operates as a regeneration pump.

That is, in FIG. 2, fluid sucked from the suction port 11, in this case gasoline in the fuel tank, flows into the C-shaped first stage flow path 7. The direction of this flow is as shown by the arrow in FIG.
0 to the first stage flow path end 12, and further to the connecting path 13.
It passes through the first stage side connection flow path 18 forming the inlet side housing 20 and reaches the center four part 39 at the center of the inlet side housing 20.

The fuel in the central recess 39 reaches the back side of the impeller 3 via the communication hole 2. That is, it reaches the back side of the impeller 3 through the through hole 26, the gap between the joint insertion hole 27, and the impeller recess 23, and reaches the four central parts 41 at the center of the outlet side housing 20.
reach. Then, from the second-stage side connection channel 19, it passes through the starting end 15 of the second-stage channel and reaches the terminal end 16 of the second-stage channel,
The fuel discharged from the discharge port 17 reaches the periphery of the rotor 31, which is outside the outlet housing 22. The fuel then passes through the gap between the rotor 31 and the magnet 33 and reaches the vicinity of the commutator 34, and then pushes open the check valve 37 and reaches the vehicle engine from the discharge pipe 38 via a discharge pipe (not shown). It is. This pump is housed in a fuel tank and is used as a high-pressure fuel pump that supplies fuel in the fuel tank to a fuel injection device of a vehicle engine.

Next, the distribution of fluid pressure acting on the circumferential surface of the impeller 3 will be explained. In FIG. 7, the pressure acting on the circumferential surface of the impeller 3 is plotted on the vertical axis, and the angle indicating the position of the circumferential surface of the impeller 30 is plotted on the horizontal axis. And the angle of 0 degrees is near the suction port,
It is indicated by reference numeral 11. And this suction port 1 with an angle of 0 degrees
FIG. 7 shows the pressure distribution rotated 360 degrees in the rotational direction of the impeller from one vicinity, that is, one rotation. 17
15 indicates the pressure near the discharge port, 15 indicates the starting end of the second stage flow path, and 12 indicates the pressure acting position near the end of the first stage flow path.

Curve 1 shows a state in which the pressure is increased by the first stage flow path 7, and the pressure gradually rises from the suction port 11, and the pressure rises to 1.
At the end of the first-stage flow path No. 2, the pressure level is P/2. Here, P is the pressure near the discharge port. Curve 2 shows the pressure distribution acting on the circumferential surface of the impeller through the second stage flow path 8. At the starting end 15 of the second stage flow path, the pressure is approximately P/2. The pressure is increased from the starting end 15, and the pressure at the discharge port 17 is increased to P. The circumferential surface of the impeller 3 connects the first stage passage 7 and the second stage passage 7.
Since it is in contact with the stage flow path 8, the pressure of curve 1 and the pressure of curve 2 act on the circumferential surface of this impeller 3. Therefore,
On the circumferential surface of the impeller 3, the average pressure of curves 1 and 2, that is, the pressure of curve 3 is acting.

On the other hand, curve 4 was created based on curve 3, and curve 4 shows the radial pressure acting on the outer peripheral surface of the impeller at a portion 180 degrees away from curve 3. This curve 4
can be easily drawn from the curve 3, and can be drawn by plotting the pressure at an arbitrary angular position of the curve vA3 at a portion 180 degrees from that position. That is, curve 3 represents the pressure acting on an arbitrary angle on the outer periphery of the impeller, and curve 4 represents the pressure acting on the opposite part 180 degrees away from that arbitrary position. The radial pressure that actually acts on the impeller 3, that is, the harmful force that presses the impeller 3 against the inner peripheral wall of the pump case 5 or acts between the impeller 3 and the claw-type joint 24 on the rotating shaft 4 side that drives it. The radial pressure is the combined pressure of curve 3 and curve 4. That is, the pressure acting on the outer periphery of any impeller 3 minus the pressure acting on the opposite side becomes the radial pressure acting on the impeller.

This pressure corresponds to the hatched area in FIG. 7, and is found to be an extremely small pressure.

On the other hand, FIG. 8 is a curve diagram showing the radial pressure of the conventional device. In FIG. 8, the parts indicated by 11'' and 15' correspond to the inlet port and the starting end of the second stage flow path of the conventional device, and these are located at almost the same angular position. , 17° is the first part of the conventional device.
It shows the part corresponding to the end of the stage flow path and the part corresponding to the discharge port. In FIG. 8, curve 1'' indicates the pressure exerted by the first stage flow path on the outer circumference of the impeller. That is, curve 1
As shown in ``, the pressure gradually increases from the suction port 11°, and at the end portion 12'' of the first stage flow path, the pressure approximately corresponds to P/2. indicates the pressure exerted on the outer periphery of the impeller 3. In other words, as shown by the curve 112°, the pressure at the part corresponding to the discharge angle 17° corresponds to approximately P, and at the part corresponding to the starting end of the second stage flow path 15°. The pressure is P/2. Next, curve 4' is curve fi3'
It is a curve created based on , and it is 180
It depicts the pressure in the advanced part. And: 8th
In the conventional device shown, the detrimental radial pressure acting on the impeller corresponds to the large hunting portion shown, which corresponds to the difference between curves 3' and 4'. That is, in conventional pumps, a large radial pressure is generated in the impeller, and a large frictional force is generated between the impeller and the pump case.

FIG. 9 shows changes in efficiency of the pump device shown in FIGS. 7 and 8, in which η represents efficiency % and Po represents discharge pressure kg/cm 2 .

The solid line represents the embodiment of the present invention shown in FIG. 7, and the broken line represents the conventional device shown in FIG. 18) The horizontal axis shows the flow rate Q (1/Hr). As is clear from FIG. 9, the efficiency of the present invention is very high, and the discharge pressure at the same flow rate is higher than that of the conventional device.

Next, other embodiments will be described.

10 to 12 show a second embodiment of the present invention, in which a first stage side connection passage 18 and a second stage side connection passage 19 constituting the connection passage 13 are shown. Both have a curved shape. That is, as shown in FIG. 12, the first-stage connecting flow path is curved so that the fluid flowing in smoothly moves from the end of the first-stage flow path to the center recess 39 side. Further, as shown in FIG. 10, the second-stage connecting channel 19 also has a curved shape so that the channel flowing out from the central recess 41 smoothly flows into the second-stage channel. In other words, if configured as in this second embodiment, the angle of the connecting portion connecting the first stage flow path 7 and the first stage side connection flow path will be gentle, and sudden changes in the fluid can be avoided.
It will flow smoothly. In addition, the second stage flow path 8 and the second
The angle of the flow path at the portion connecting to the stage-side connection flow path 19 is also gentle, and the friction loss of the fluid flowing therein is reduced.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing a first embodiment of the regeneration pump device according to the present invention, FIG. 2 is a partial cross-section along the tr-curve in FIG. 1, and FIG. 3 is the same as shown in FIG. Elevation view of the impeller part,
FIG. 4 is a partial sectional view taken along the arrow TV-IV line shown in FIG. 1. 5 and 6 are top and bottom views of the impeller of the pump device shown in FIG. 1, respectively. FIG. 7 is a curve showing the distribution of radial pressure acting on the impeller of the pump device of the first embodiment, FIG. 8 is a curve showing the distribution of radial pressure of the conventional device, and FIG. 9 is a curve showing the distribution of radial pressure acting on the impeller of the pump device of the first embodiment. It is a graph showing the change rate of pump efficiency and discharge pressure with respect to the flow rate, comparing the example and the conventional device. 10 to 12 show a second embodiment of the device of the present invention, in which FIG. 10 is a partial sectional view corresponding to the above-mentioned FIG. 4, and FIG. 11 is an elevation view corresponding to FIG. 3. FIG. 12 is a partial sectional view corresponding to FIG. 2. 1...Blade groove, 2...Communication hole, 3...Impeller,
4... Rotating shaft, 5... Pump case, 6... First
Stage flow path, 7... Second stage flow path, 9... Partition wall, 10.
...Starting end of the first stage flow path, 11... Suction port, 12...
The end of the first stage flow path. 13... Connection passage, 15... Starting end of second stage flow path, 1
6... End of second stage flow path, 17... Discharge port, 18...
. . . 1st stage side connection flow path, 19 . . . 2nd stage side connection flow path. Representative Patent Attorney Takashi Okabe

Claims (2)

[Claims] (1) An impeller (3) in which a plurality of blade grooves (1) are formed on the outer periphery of both sides of a disc, and a communication hole (2) is formed in the center to connect the two sides. A rotating shaft (4) for rotating the impeller (3), a pump case (5) that houses the impeller (3), and an inner wall of the pump case and the impeller (3) on the outer periphery of both sides of the impeller (3), respectively. The annular first and second stage channels (7
), (8), a partition wall (9) that partitions a part of the first and second stage flow paths (7) and (8), respectively, and a partition wall (9) connected to the starting end (10) of the first stage flow path. Suction port (1
1), a connecting passage (13) connecting the terminal end (12) of the first stage flow path and the starting end (15) of the second stage flow path;
In a regeneration pump device comprising a discharge port (17) connected to a terminal end (16) of a stage flow path, the start end (10) of the first stage flow path and the start end (15) of the second stage flow path; is substantially 1 when viewed from the center of the impeller (3).
The impeller (3) is arranged at point-symmetrical positions that are 80 degrees opposite to each other, and the terminal end (12) of the first stage flow path and the terminal end (16) of the second stage flow path are connected to the impeller (3). Really 1 from the center of
They are arranged at point-symmetrical positions that are 80 degrees opposite to each other, and the connecting passage (13) is connected to the terminal end (13) of the first stage flow passage.
12) and the communication hole (2) in the center of the impeller; A regeneration pump device characterized by comprising a second stage side connection channel (19) connecting the hole (2). (2) The first stage side connection flow path (18) and the second stage side connection flow path (18)
2. The regeneration pump device according to claim 1, wherein the stage-side connection channel (19) has a curved shape.