JPH0565896A - Vortex flow pump - Google Patents

Abstract

PURPOSE:To lower the noise level by providing a section reducing means partly in an interval at least from the center over to a delivery port of a part reaching the delivery port from a suction port, of annular grooves provided in the part opposed to blades of an impeller in a casing. CONSTITUTION:A single-blade cup-shaped vortex flow pump having a plurality of sheets of blades 1a in annular grooves 1b provided in an impeller 1 is formed by storing the impeller 1, mounted to a rotary shaft 14 of a prime mover 11, in a casing 3 of providing a suction port 3b and a delivery port 3c. An annular groove 3a opened to face an impeller 1a is provided so as to reach the delivery port 3c from the suction port 3b along the direction of rotation of the impeller 1, in a part opposed to the blade 1b of the impeller 1 in the casing 3. Here, a section contraction part 3f formed of slope-shaped protruding parts is provided at least from a center 3e over to the delivery port 3c in a part of reaching the delivery port 3c from the suction port 3b of the annular groove 3a, and a flow of air is accelerated to contrive increase of an amount of air.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a casing annular groove structure suitable for improving the performance of a vortex gas pump (vortex blower) or a vortex liquid pump (wesco pump).

[0002]

2. Description of the Related Art In a conventional single-blade vortex flow pump, an annular groove structure of a casing is disclosed in, for example, Japanese Patent Laid-Open No. 51-705.
As described in No. 12, the annular groove is formed in a substantially semi-elliptical shape, and the outer diameter of the annular groove is D2, the inner diameter is D1, and the depth is d, where d <(D2-D1) / 4. Therefore, backflow is prevented and a swirl blower with a small static flow and high static pressure is obtained.

Further, in a conventional double-blade vortex flow pump, as an annular groove structure of a casing, for example, Japanese Patent Laid-Open No. 49-
As described in Japanese Patent No. 135209, an output is improved by providing an annular protrusion on the outer peripheral side of the annular groove to prevent the generation of vortices.

[0004]

The above-mentioned prior art relates to a high static pressure in a small air volume range, and a structure for reducing noise has not been considered.

In the above-mentioned prior art, since the shallow portion of the protrusion or groove is provided on the entire circumference of the annular groove, there is a problem that the cross-sectional area of the portion of the annular groove from the suction port to the center of intake and discharge is reduced and the air volume is reduced. is there. Further, the reduction of the cross-sectional area in this portion hardly contributes to the reduction of noise.

It is an object of the present invention to provide a vortex pump capable of reducing the noise level and achieving a high static pressure in the entire air volume range.

[0007]

[Means for Solving the Problems] The above object is to provide an impeller,
A casing having a suction port and a discharge port for accommodating the impeller is provided, and a portion of the casing facing the blade of the impeller extends along the rotation direction of the impeller from the suction port to the discharge port. In the vortex pump having an annular groove provided facing the blade and opening, in the annular groove, at least a part of a portion from the suction port to the discharge port of the annular groove from the center to the discharge port This is achieved by providing a cross-section reduction means for reducing the cross-sectional area of

In a preferred embodiment, the cross-section reducing means has a cross-section cut by a plane passing through the rotation axis and formed by a slanting projection extending from the vicinity of the outer peripheral edge of the annular groove to the bottom surface of the annular groove. It

In another preferred embodiment, the annular groove has a depth from a surface of the casing facing the impeller, an intermediate position between the central portion of the annular passage and the suction port, and the annular passage. It becomes deeper in the order of the central portion, the intermediate portion between the central portion of the annular flow passage and the discharge port.

[0010]

The impeller is driven by the prime mover to rotate and generate an internal flow of the fluid flowing out from the outer peripheral portion. The cross-section reducing means forms an inclined surface with respect to the internal flow flowing out from the impeller and guides the internal flow to the inner peripheral side so as to positively change the course. As a result, the internal flow flowing out from the outer peripheral portion of the impeller is guided to the inner peripheral side and closely flows with the flow flowing out from the portion away from the outer peripheral portion of the impeller. Therefore, the separation due to the speed difference between the flow flowing out from the outer peripheral portion of the impeller and the flow flowing out from the portion away from the outer peripheral portion is reduced, so that the generation of sound can be suppressed, and at the same time, the loss due to the turbulence of the internal flow is also reduced. By being suppressed, the static pressure can be increased.

Further, near the deadline operation, the internal flow is promptly guided to the inner peripheral side and the inflow speed at the inner peripheral portion of the impeller is reduced to suppress the generation of noise, and at the same time, the loss due to the turbulence of the internal flow is caused. By also suppressing, it is possible to obtain an increase in static pressure.

Further, since the flow passage area is secured on the suction side, it is possible to prevent a decrease in the air volume.

[0013]

EXAMPLES Examples of the present invention will be described below with reference to FIGS.

A first embodiment of the present invention will be described with reference to FIGS. 1 to 5 and 18 to 21. The present embodiment is an example in which the present invention is applied to a cup type vortex flow pump.

The cup type vortex flow pump is a single-blade vortex flow pump having a plurality of blades 1a in an annular groove 1b provided in an impeller 1 as shown in FIGS.

The impeller 1 is provided so as to rotate around a rotary shaft 14 of a prime mover 4, and a suction port 3 is provided in a casing 3.
b and the discharge port 3c are provided, and there is a space in which the impeller 1 is stored. In this embodiment, an induction motor is used as the prime mover 4. In the portion of the casing 3 facing the blade 1a of the impeller 1, the casing annular shape is provided so as to extend from the suction port 3b to the discharge port 3c along the rotation direction of the impeller 1 and opens toward the blade 1a. A groove 3a (hereinafter referred to as an annular groove 3a) is provided.

The impeller 1 has a large number of blades 1a and an annular groove 3a.
The annular groove 1b of the impeller 1 (hereinafter referred to as the impeller annular groove 1b) is disposed so as to cross the annular groove 3a via a minute gap g.
To face.

A part of the circumference of the annular groove 3a between the suction port 3b and the discharge port 3c is partitioned by a partition wall portion 3d, and the impeller 1 rotates at the bottom of the annular groove 3a adjacent to the partition wall portion 3d. The suction port 3b is opened at the end point side in the direction, and the discharge port 3c is opened at the start point side in the rotation direction of the impeller 1. Annular groove 3
A cross-section reducing means for reducing the cross-sectional area in the annular groove 3a is provided in at least a part of a section from a suction port 3b to the discharge port 3c in the section a, from at least the center (hereinafter referred to as the suction / discharge center 3e) to the discharge port 3c. It is a thing.

In this embodiment, the cross-section reducing means has a cross-section cut along a plane passing through the rotation axis from the vicinity of the outer peripheral edge of the annular groove 3a (near the minute gap g with the outer circumference of the impeller 1). 3f is a cross-sectional reduction portion 3f formed by a slope-shaped projecting portion reaching the bottom surface.

In this embodiment, as shown in FIG.
The cross-section reducing means is provided in 70% of the section of the annular groove 3a from the suction / discharge center 3e to the center of the discharge port 3c near the suction / discharge center 3e.

Specifically, in this embodiment, the angle from the suction / discharge center 3e to the center of the discharge port 3c is 160 degrees,
The cross-section reducing means is provided in the suction and discharge centers 3e to 112.
It is a section up to degrees.

The range of the section where the cross-section reducing means is provided is such that the maximum starts from the intake / exhaust center 3e and reaches the position of an angle of 112 degrees along the annular groove in the discharge port direction, and the minimum is experimentally. It is a section starting from the position of 30 degrees along the annular groove in the discharge port direction from the suction / discharge center 3e to the position of 90 degrees. At this time, the length of the section of the section reducing means is about 40% of the maximum value.

The cross-section reducing means may be provided at the portion of the discharge port or the suction port as described in Japanese Patent Application No. 2-279013. In this case, on the discharge side, the internal flow partition 3
The part that collides with d is suppressed, the flow becomes smoother, and the noise can be further reduced. On the suction side, the internal flow is guided so as to pass near the impeller 1, and the speed is given from the impeller 1. As a result, the air volume can be increased because it is accelerated sufficiently.

In the present embodiment, the prime mover 4 is the rotary shaft 1
Rotate the impeller 1 about 4 to rotate the impeller annular groove 1
3 (a) by the plurality of blades 1a in FIG.
As shown in (b), an internal flow is generated in the annular groove 3a and the impeller annular groove 1b.

In other words, the structure is such that an internal flow having a swirl from the suction port 3b of the casing to the discharge port 3c through the suction / discharge center 3e and the cross-section reducing means 3f is formed.

In this embodiment, from the suction port 3b to the suction and discharge center 3e, the impeller 1 is sufficiently accelerated in the rotation direction 1
At the same time as the next flow, an internal flow having a secondary flow that swirls in the annular flow paths 1b and 3a is formed, and this internal flow extends from the suction / discharge center 3e to the discharge port 3c in a shape exaggeratedly shown by a ridge line shape in FIG. By passing through the cross-sectional reduced portion 3f, the flow smoothly without causing peeling. Therefore, it is possible to prevent the occurrence of flow turbulence due to separation, and thus to prevent noise and pressure loss.

The internal flow near the deadline operation is as shown in FIGS. In this case, generation of noise is suppressed by promptly being guided to the inner peripheral side through the cross-sectional reduced portion 3f having an exaggerated ridge line shape in FIG. 4 to reduce the inflow speed at the inner peripheral portion of the impeller. The static pressure can be increased by suppressing the loss due to the turbulence of the internal flow.

Here, as shown in FIG. 18, the internal flow 30 flows out from a point S1 on the outer peripheral side of the impeller 1, flows into the annular groove 3a of the casing at a high speed, and the blades on the outer peripheral side of the annular groove 3a. The flow in the rotational direction of the vehicle 1 reaches the point S2, but the flow does not flow to the discharge port 3c as it is, but only the effective outflow portion of the annular groove 3a flows, so that the flow is in the rotational direction on the inner peripheral side of the annular groove 3a. On the opposite side, the flow returns to the point S3 close to the original outflow point S1.

That is, the flow on the outer circumference and the inner circumference is as follows: Outer side of the casing: S1 → S2 (flowing by the advancing angle θ2 in the rotating direction) Inner side of the casing: S2 → S3 (in the direction opposite to the rotating direction) The return angle θ2 'flows).

That is, the flow flowing out from the point S1 on the outer peripheral side of the impeller 1 does not return to the point S1 when returning to the inner peripheral side of the impeller 1, but returns to the point S3 advanced in the rotational direction by the carry-forward flow rate QIK.

As in the conventional case, if the flow passage cross section of the annular groove 3a is semicircular, points S1 to S2 are provided on the outer peripheral side of the annular groove 3a.
Since the flow angle greatly flows up to the angle θ2 ′ even when the inner peripheral side of the annular groove 3a returns from the point S2 to the point S3, the flow state from the point S3 to the impeller is as follows.
As shown in FIG. 20, it flows into the impeller at a flow velocity w1.

The noise at the deadline of the vortex flow blower is largely due to the magnitude of the turbulence associated with the flow inflow on the inner peripheral side of the impeller. When the internal flow was measured, the flow velocity w
Since 1 is about twice as large as u2, it has the drawbacks that the turbulence of the flow when flowing into the blade is large and the amount of noise generated is large.

For example, when the internal flow of a vortex flow blower with a blade diameter D2 of 210 mm and a rotation speed of 2850 rpm was measured, the blade peripheral speed u2 was 31.3 m / s and C2 was 78.5 m / s at the cutoff point. (C2 does not differ depending on the presence or absence of the cross-section reducing means 3f in the casing),
C1 is 76.5m / s, w1 is 93.5m / s,
As shown in FIG. 22, the frequency component (fluid noise) at 200 to 1000 Hz and the frequency component near 2000 Hz (siren sound) were large, and the noise level was 63 db overall.

According to this embodiment, if the cross section of the annular groove 3a is not semicircular and the flow passage area on the outer peripheral side of the annular groove 3a is reduced as shown in FIG. 3, the flow also changes from 30 to 30 'as shown in FIG. , The lengths of the arcs S1 and S2 are also shorter than before,
The advancing angle of the flow in the rotational direction is also significantly reduced from the conventional θ2 to θ2 '.

When the traveling angle on the outer peripheral side of the flow annular groove 3a becomes smaller, a point S2 on the inner peripheral side of the flow annular groove 3a becomes smaller.
Therefore, the return angle from S3 to point S3 is also small,
As in No. 9, the inflow velocity of the flow into the impeller is w2 ', which is significantly smaller than the conventional w2.

When the above-mentioned impeller diameter D2 is 210 mm,
The blade inflow velocity w2 'of this embodiment was 65.2 mm, which was significantly smaller than the conventional w1 of 93.5 m / s. As a result, the turbulence of the flow due to the inflow of the blades is also significantly reduced, and as shown in FIG.
Since the frequency component near 000 Hz was attenuated, the overall noise level was 56 db, and it was possible to achieve noise reduction of 7 db compared to the conventional case.

Also, the power could be reduced by about 30% by reducing the turbulence.

As described above, in the present embodiment, the outer peripheral side of the casing annular groove of the cup-type vortex pump has a means for reducing the cross section by the inclined surface starting from the vicinity of the minute gap on the outer peripheral side, and the internal flow flowing out from the outer peripheral portion of the impeller. Is positively guided to the inner peripheral side along this slope to prevent flow separation, resulting in low noise and high static pressure. Specifically, the noise level can be reduced to about 7 dB, that is, the generated noise energy can be reduced by up to 20%. At the same time, the effect of increasing the pressure by about 10% can be obtained.

The cross-section reducing means 3f may be formed as a separate member from the casing and attached to the annular groove 3a so as to guide the internal flow to the inner peripheral side along the slope of the separate member. The casing is generally formed by aluminum die casting, but the cross-section reducing means 3f may be formed by a steel material, a ceramic material, a fluororesin, or the like.

That is, as shown in FIG. 3, the cross-section reducing means 3
By using f as a separate member from the annular groove 3a, it is possible to optimize the shape, enable the use of wear-resistant materials and the use of corrosion-resistant materials, and facilitate the replacement during wear. As a result, it becomes possible to maintain a good cross-section reducing means even in the vortex flow pump that is exposed to an internal flow velocity that is twice the peripheral velocity.

A second embodiment of the present invention will be described with reference to FIGS.

In this embodiment, in order to make the function of the slope as the cross-section reducing means more effective, the position considered to be approximately the center of the slope is specified.

In this embodiment, when the inner and outer diameters of the annular groove 3a are D1 and D2, respectively, as shown in FIG. 6, the annular groove 3a extending from the suction port 3b to the discharge port 3c is shown.
Of at least the section from the discharge center 3e to the center of the discharge port 3c, 70% of the section closer to the discharge center 3e, the depth P1 of the flow path surface at the diameter of (3D2 + D1) / 4 in the annular groove 3a. The surface position of the inclined surface is configured to be shallower by (D2-D1) / 8 or more than the depth of the bottom surface of the annular groove 3a at the center diameter (D2 + D1) / 2 of the annular groove 3a.

That is, in this embodiment, since the angle from the discharge center 3e to the center of the discharge port 3c is 160 degrees, the depth of the annular groove has the above relationship in the section from the discharge center 3e to 112 degrees. While becoming shallower.

In this section, if necessary, of the section from the suction / discharge center 3e to the center of the suction port 3b, 7 near the suction / discharge center 3e.
It may extend to a relatively long section.

On the discharge side from the suction / discharge center 3e, the component in the circumferential direction becomes larger than the component in the swirling direction. Therefore, low noise measures and the like may be mainly performed on this circumferential component. In order to reduce noise due to flow turbulence, it is important to prevent flow separation on the outer peripheral side. For this purpose, it is conceivable to reduce the cross-sectional area of the annular groove, but if it is simply reduced, there is a problem that the air flow rate decreases because the flow passage becomes too narrow.

In this embodiment, the cross-section reducing means is provided on the outer peripheral side as described above to secure the cross-sectional area on the inner peripheral side and to maintain the air volume.

With this structure, the separation of the air flow can be effectively prevented, the loss due to the turbulence of the internal flow can be suppressed, and the static pressure can be increased.

FIG. 7 shows a first modification of the present embodiment. In order to use the annular groove 3a section reducing means 3f more effectively, the intermediate position of the section reducing means 3f is used as a reference position P1 in FIG.
This is an example of a shallower position.

FIG. 8 shows a second modification of this embodiment, in which the cross-section reducing means 3f is provided from the inner and outer edges of the annular groove 3a toward the bottom surface of the annular groove, and the depth at the position P1. Is similar to that of FIG.

FIG. 9 shows a third modification of this embodiment.
The cross-section reducing means 3f is started on the outer peripheral side of the annular groove 3a with a slight gap from the vicinity of the position (edge) where the minute gap g is formed between the outer peripheral side of the impeller 1 and the outer peripheral side of the impeller 1, and then on the bottom surface of the annular groove 3a. It is formed of a slope-shaped projecting portion.

The cross-section reducing means 3f of the annular groove 3a is set with a slight clearance from the edge on the outer peripheral side of the annular groove, and the outer peripheral side vertical portion is left a little to facilitate positioning.

FIG. 10 shows a fourth modification of the present embodiment. In order to use the cross-section reducing means 3f of the annular groove 3a more effectively, the position on the outer peripheral side of the cross-section reducing means 3f is used as a reference in FIG. In this example, the depth is shallower than P1.

In this modification, (3D2 + D of the annular groove 3a is
1) / 4 diameter P1 point and annular groove 3 in the same cross section
The depth of the tangent to the curve showing the channel shape from (3D2 + D1) / 4 to D2 having a diameter of a is smaller than (D2-D1) / 10 at the minute gap surface at D2. It is a thing.

A third embodiment of the present invention will be described with reference to FIG. In this embodiment, the impeller 1, the suction port 3b and the discharge port 3c are used.
A casing 2 for accommodating the impeller 1 is provided, and a portion of the casing 2 facing the blade 1a of the impeller 1 extends from the suction port 3b to the discharge port 3c along the rotation direction of the impeller 1.
Annular groove 3 provided to reach the blade 1a and opening toward the blade 1a
In the swirl pump having a, the annular groove 3a is formed in at least a part of a section from the inlet 3b to the outlet 3c of the annular groove 3a at least from the center 3e to the outlet 3c.
The annular groove 3a is provided with a cross-section reducing means 3f for reducing the inner cross-sectional area, and the annular groove 3a has a depth from the surface of the casing 2 facing the impeller 1 at an intermediate position between the central portion 3e of the annular groove 3a and the suction port 3b. The central portion 3e of the groove 3a, the central portion 3e of the annular groove 3a and the middle position of the ejection port 3c are deepened in this order.

FIG. 11 is a sectional view taken along the circumferential direction AA, C of FIG.
The cross section at -C and DD is shown, and the depth is in this order. Get deeper. The present embodiment is an example in which the noise level can be reduced or the static pressure can be increased by the cross-section reducing means 3F even in the large air volume range when opened, and the air volume can be secured because the DD cross section is wide. ..

A fourth embodiment of the present invention will be described with reference to FIG. In this embodiment, the inclined surface of the annular groove 3a is the same member as the casing 2, and the inner surface of the annular groove 3a is formed in an inclined surface projecting toward the inner side of the annular groove in the inclined surface forming range of the casing. FIG. 12A shows the wall thickness T at the maximum wall thickness portion in the slope forming range of the casing 2,
The thickness is set to be twice or more the wall thickness t of a portion where no slope is formed on the same circumference.

As shown in the figure, by providing a thick wall portion of the casing,
By forming the cross-section reduced portion 3f, failure prevention during wear,
Good manufacturability and quickness can be obtained by cutting the casting mold. Further, by increasing the thickness of the casing, it is possible to improve durability against wear.

FIG. 12 (b) shows a modification of this embodiment, in which the member of the annular groove 3a is projected inward without changing the plate thickness, and is formed in the shape of an inclined surface projecting inward of the annular groove 3a. It is a thing. According to this configuration, it is possible to save the material and to measure the material.

In a vortex flow pump, the maximum internal flow speed is generally about twice the peripheral speed of the impeller, and such consideration is necessary because of the high speed flow.

In the above embodiment, the shape applied to the cup type is shown, but it is easy to increase the suction side cross-sectional shape even in the double blade type, and it is possible to carry out in the same manner.

A fifth embodiment of the present invention will be described with reference to FIGS.

The present embodiment is an example in which the present invention is applied to a double-blade vortex flow pump. The basic configuration of this embodiment is shown in FIGS.
5 will be described. The present embodiment has means for reducing the cross-section on the outer peripheral side of the casing annular groove of the double-blade vortex pump by the slope inclined from the vicinity of the minute gap to the side of the impeller, and the internal flow flowing out from the outer peripheral part of the impeller is It positively guides to the side of the impeller along the slope and reaches the discharge port or the inner circumference of the impeller.

The structure of this embodiment has a double vane type impeller 101 having a large number of vanes 101a protruding substantially radially with respect to the rotating shaft on the outer peripheral portion thereof, and a side face corresponding to the vane 101a of the impeller 101. And a casing 102 having an annular groove 103a on the outer peripheral side, a side cover 115 having an annular groove 115a opening to the side and the outer peripheral side corresponding to the blade 101a of the impeller 101, and a part of the casing annular groove 101a on the circumference. Partition wall portion 103d and casing partition wall portion 10
In the double-blade vortex pump having a suction port 103b that is adjacent to the impeller 101 and opens on the axial direction side of the impeller 101, and a discharge port 103c that is adjacent to the casing partition wall portion 103d and that is open on the side facing the impeller rotation, an annular groove The cross-section reducing means 10 that reduces the cross-sectional area in the annular groove 103a in at least a part of a section from the suction port 103b to the discharge port 103c of the portion 103a to the discharge port 103c.
It is provided with 3f.

In this embodiment, the double-blade impeller 101 is rotated by the prime mover 4, and an internal flow is generated as in the cup-type vortex pump. In this case, the suction port 103
The primary flow that is sufficiently accelerated in the rotation direction of the impeller 101 from b to the intake / exhaust center 103e and the internal flow that has the secondary flow swirling between the blades 101a and the annular flow passage 103a as components are formed. In addition, the internal flow smoothly flows from the suction / discharge center 103e to the discharge port 103c without passing through the cross-sectional reduction portion 103f.

FIGS. 14 and 15 show the basic operation of the double-blade vortex flow pump of this embodiment. The flow flowing out from the center of the outer peripheral portion of the impeller 101 is the cross-section reducing means 103f due to the slope of this embodiment. Is guided to the side of the annular groove 103a by
The internal flow, which is slightly displaced from the center of the outer peripheral portion of the impeller, is guided to the side of the annular groove 103a and closely flows. Therefore, since the separation due to the speed difference between the flow that flows out from the center of the outer peripheral part of the impeller and the flow that deviates from the center of the outer peripheral part of the impeller, which occurs in the past, is reduced, the sound generation can be suppressed, and at the same time the internal sound can be suppressed. Since the loss due to the turbulence of the flow is also suppressed, the static pressure can be increased.

Therefore, according to this embodiment, it is possible to reduce the noise level and increase the static pressure of the double-blade vortex flow pump.

As shown in FIG. 16, the diameter of the radial gap surface on the outer peripheral side of the casing annular groove 103a is D1, the maximum diameter on the outer peripheral side of the casing annular groove 103a is D2, as shown in FIG. When the side gap is g2 and the face width is B, 70% of the section from the center of suction and discharge on the outer peripheral side of the casing annular groove to the center of the suction port, and 70% of the section near the center of discharge and the center of discharge port from the center of discharge. In the 70% section near the intake / exhaust center of the section up to, the depth of the flow passage surface at the diameter (D2 + D1) / 2 of the casing annular groove is the radial direction on the outer peripheral side of the annular groove on the side gap g2 surface. The shape is shallower than the maximum depth by (D2-D1) / 8 or more.

As shown in FIG. 15, the means 103f for reducing the cross section by the slope is attached to another member, and the internal flow is guided to the side of the impeller along the slope of this separate member to the discharge port or the inner circumference of the impeller. It may be configured to reach.

A first modification of this embodiment will be described with reference to FIG. In order to make the function of the slope more effective in this modification, after the start position of the slope is specified and the section reducing means of the casing annular groove is started near the minute gap g1 and with a slight gap, It is formed by a slope inclined in the side direction. In this modification, as shown in FIG. 15, the cross-section reducing means 103f of the annular groove 103a is the casing annular groove 1
In the vicinity of the outer peripheral side gap portion g1 of 03a and the gap g1
Therefore, it is set with a slight gap. This gap can be used as a reference for positioning.

A second modification of this embodiment will be described with reference to FIG. In this modification, the annular groove 103a cross-section reducing means 10 is used.
This is an example in which the intermediate position of the cross-section reducing means 103f is shallower than the position P1 which is the reference in the first modification in order to use 3f more effectively. In this modification, as shown in FIG. 17, the depth from the minute gap surface g1 to P1 is (D2-
D1) / 10 or less, the annular groove 103a
The cross section of is further reduced to improve the effect of guiding the airflow to the inner peripheral side.

As a third modification of this embodiment, the depth from the casing micro gap surface on the outer peripheral side of the casing 102 is determined by the suction / discharge center 103e and the casing suction port 103.
Intermediate position with b, suction / discharge center 103e, suction / discharge center 103e
The intermediate position between the discharge port 103c and the discharge port 103c may be increased in this order (not shown). In this modified example, considering the large air flow characteristic, on the suction side in the circumferential direction, the outflow from the outer peripheral side of the impeller is sucked from the suction port by arranging the outflow from the outer peripheral side of the impeller without providing a slope on the outer peripheral side of the casing annular groove. It is a flow that does not intersect with the flow. According to this modification, by adding the designation of the cross section of the suction side flow path, the maximum air flow rate is increased by about 20% as compared with the case where the cross section of the suction and discharge center is continuous from the suction port to the suction and discharge center at a constant value. Can be planned.

In this modified example, the wall thickness in the slope forming range of the casing is made twice as large as that of the other portions, so that the slope portion 103f becomes thicker, and the casing 102 due to abrasion with the high speed flow from the impeller 101. It is possible to prevent damage such as hole punching.

[0074]

According to the present invention, since the internal flow can be prevented from being separated by the annular groove reducing means, it is possible to obtain a vortex pump capable of reducing the noise level and increasing the static pressure in the entire air volume range. With the goal.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of the configuration of a first embodiment of the present invention.

FIG. 2 is a plan view of the flow channel according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view of the flow channel of this embodiment, (a) of FIG.
-A sectional view, (b) is a BB sectional view.

FIG. 4 is a diagram showing a flow path ridge line according to the present embodiment.

FIG. 5 is a vertical sectional view showing the overall structure of the present embodiment.

FIG. 6 is a sectional view of a flow channel according to a second embodiment of the present invention.

FIG. 7 is a flow path cross-sectional view of a first modified example of the present embodiment.

FIG. 8 is a flow path cross-sectional view of a second modified example of the present embodiment.

FIG. 9 is a flow path cross-sectional view of a third modified example of the present embodiment.

FIG. 10 is a flow path cross-sectional view of a fourth modified example of the present embodiment.

FIG. 11 is a sectional view of a flow channel according to a third embodiment of the present invention.

12A and 12B are sectional views showing a fourth embodiment of the present invention, wherein FIG. 12A is a sectional view of a flow channel of the present embodiment, and FIG. 12B is a sectional view of a flow channel of a modified example of the present embodiment.

FIG. 13 is a vertical sectional view of a fifth embodiment of the present invention.

FIG. 16 is a plan view of the flow channel of this embodiment.

FIG. 15 is a cross-sectional view of the flow channel of this example, in which (a) is FIG.
A-A sectional view, and (b) is a BB sectional view.

FIG. 16 is a sectional view of a flow path of a first modified example of the present embodiment.

FIG. 17 is a sectional view of a flow path of a second modified example of this embodiment.

FIG. 18 is a plan view showing the air flow in the flow channel according to the first embodiment of the present invention.

19A and 19B are diagrams showing the internal flow in the flow channel of the first embodiment of the present invention, FIG. 19A being a sectional view taken along line AA of FIG. 18, and FIG.
FIG. 6 is a circumferential internal flow distribution diagram in cross section.

FIG. 20 is a velocity triangle diagram of the internal flow in the cross section of FIG. 18B-B.

FIG. 21 is a diagram showing a noise spectrum according to the first embodiment of the present invention.

FIG. 22 is a diagram showing a noise spectrum of a conventional vortex flow blower.

[Explanation of symbols]

1, 101 ... Impeller, 2, 102 ... Casing, 3a,
103a ... Casing annular groove, 3b, 103b ... Casing suction port, 3c, 103c ... Casing discharge port, 3
d, 103d ... partition walls, 3e, 103e ...
f, 103f ... Cross-section reducing means, 1a, 101a ... Impeller blades, 1b ... Impeller annular flow path.

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[Procedure amendment]

[Submission date] September 29, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief explanation of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is an exploded perspective view of the configuration of a first embodiment of the present invention.

FIG. 2 is a plan view of the flow channel according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view of the flow channel of this embodiment, (a) of FIG.
-A sectional view, (b) is a BB sectional view.

FIG. 4 is a diagram showing a flow path ridge line according to the present embodiment.

FIG. 5 is a vertical sectional view showing the overall structure of the present embodiment.

FIG. 6 is a sectional view of a flow channel according to a second embodiment of the present invention.

FIG. 7 is a flow path cross-sectional view of a first modified example of the present embodiment.

FIG. 8 is a flow path cross-sectional view of a second modified example of the present embodiment.

FIG. 9 is a flow path cross-sectional view of a third modified example of the present embodiment.

FIG. 10 is a flow path cross-sectional view of a fourth modified example of the present embodiment.

FIG. 11 is a sectional view of a flow channel according to a third embodiment of the present invention.

12A and 12B are sectional views showing a fourth embodiment of the present invention, wherein FIG. 12A is a sectional view of a flow channel of the present embodiment, and FIG. 12B is a sectional view of a flow channel of a modified example of the present embodiment.

FIG. 13 is a vertical sectional view of a fifth embodiment of the present invention.

FIG. 14 is a plan view of the flow channel of this embodiment.

FIG. 15 is a cross-sectional view of the flow channel of this example, in which (a) is FIG.
A-A sectional view, and (b) is a BB sectional view.

FIG. 16 is a sectional view of a flow path of a first modified example of the present embodiment.

FIG. 17 is a sectional view of a flow path of a second modified example of this embodiment.

FIG. 18 is a plan view showing the air flow in the flow channel according to the first embodiment of the present invention.

19A and 19B are diagrams showing the internal flow in the flow channel of the first embodiment of the present invention, FIG. 19A being a sectional view taken along the line AA of FIG. 18, and FIG.
FIG. 6 is a circumferential internal flow distribution diagram in cross section.

FIG. 20 is a velocity triangle diagram of the internal flow in the cross section of FIG. 18B-B.

FIG. 21 is a diagram showing a noise spectrum according to the first embodiment of the present invention.

FIG. 22 is a diagram showing a noise spectrum of a conventional vortex flow blower.

[Explanation of Codes] 1, 101 ... Impeller, 2, 102 ... Casing, 3a,
103a ... Casing annular groove, 3b, 103b ... Casing suction port, 3c, 103c ... Casing discharge port, 3
d, 103d ... partition walls, 3e, 103e ... suction / discharge center, 3
f, 103f ... Cross-section reducing means, 1a, 101a ... Impeller blades, 1b ... Impeller annular flow path.

Front page continuation (72) Inventor Toshiharu Yoshitomi 1-1-1, Higashi Narashino, Narashino, Chiba Prefecture Hitachi Narashino Factory, Ltd. (72) Inventor Hiroshi Asabuki 7-1-1, Higashi Narashino, Narashino, Chiba Hitachi Narashino Factory Narashino Factory (72) Kazuo Kobayashi 7-1-1 Higashi Narashino Narashino City, Chiba Prefecture Hitachi Narashino Factory

Claims (8)

[Claims] 1. An impeller, and a casing having a suction port and a discharge port for accommodating the impeller, the portion of the casing facing the blade of the impeller being arranged along the rotation direction of the impeller. In a vortex pump having an annular groove provided so as to extend from the suction port to the discharge port and open toward the vane, in the annular groove, from at least the center of the portion from the suction port to the discharge port to the discharge port. A swirl pump, comprising a cross-section reducing means for reducing the cross-sectional area in the annular groove in a part of the section. 2. The cross-section reducing means is characterized in that a cross-section cut along a plane passing through a rotation axis is formed by an inclined projecting portion extending from the vicinity of the outer peripheral edge of the annular groove to the bottom surface of the annular groove. The swirl pump according to claim 1. 3. The vortex flow pump according to claim 1, wherein the cross-section reducing means is composed of a member different from the casing. 4. The depth of the annular groove from the surface of the casing facing the impeller is an intermediate position between the annular groove central portion and the suction port, the annular groove central portion, and the annular groove central portion. The vortex pump according to claim 1 or 2, wherein the depth becomes deeper in the order of an intermediate position between the discharge port and the discharge port. 5. An impeller having a large number of blades projecting generally in the outer peripheral direction from the rotational axis of a wheel that can rotate about the rotational axis, and annular grooves on the lateral and outer peripheral sides corresponding to the blades of the impeller. The casing has, a side cover having an annular groove that opens to the side and the outer peripheral side corresponding to the blades of the impeller, a partition wall partitioning a part of the circumference of the casing annular groove, and a shaft adjacent to the casing partition wall to the impeller. In a double-blade vortex pump that has as its constituent elements a suction port that opens in the direction side and a discharge port that is adjacent to the casing partition wall and that faces the rotation of the impeller, the suction port of the annular groove The vortex flow pump characterized by having a cross-section reducing means for reducing the cross-sectional area in the annular groove in at least a part of the section from the center to the discharge port. 6. The cross-section reducing means is characterized in that a cross-section taken along a plane passing through a rotation axis is formed by a slanted projection extending from the vicinity of the outer peripheral edge of the annular groove to the bottom surface of the annular groove. The vortex pump according to claim 5. 7. The vortex flow pump according to claim 5, wherein the cross-section reducing means is constituted by a member different from the casing. 8. The depth of the annular groove from the surface of the casing facing the impeller is intermediate between the central portion of the annular flow passage and the suction port, the central portion of the annular flow passage, and the annular flow. 7. The vortex flow pump according to claim 5, wherein the vortex pump is deepened in the order of an intermediate position between the central portion of the passage and the discharge port.