JPS59119093A - Open type volute pump with single blade type impeller - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention has a single vane type impeller and a viscous fluid, especially K
Jx, an open-type centrifugal pump specifically designed for pumping fluids containing structured substances.

[Prior art]

The discharge end of the vane lightly welds and passes through the wall through which the impeller axle passes through, leaving a gap, and the side surface of the vane on the discharge side of the pump does not reach the wall. It ends in a leading edge that extends between the tip of the blade's terminal edge and the impeller boss.

In this type of centrifugal pump, the housing wall through which the impeller axle passes is positioned in a radial plane and is covered axially with vanes to a large extent, which is similar to the front of the known centrifugal pump. However, this is because it is quite short.

As a result, a relatively small amount of the fluid (medium) pumped is
/・It just reaches the Uzing wall.

Therefore, this small amount of fluid cannot engage the vane side on the discharge side, and at the same time cannot convey this medium into the discharge conduit.

[Purpose of the invention]

It is an object of the invention to provide a centrifugal pump of the general type mentioned above, in which the housing wall and the leading edge cooperate in such a manner that even viscous fluids can be pumped satisfactorily. .

[Summary of the invention]

In the centrifugal pump according to the present invention, which achieves the above object, the housing wall is in the shape of a right truncated cone, and the front edge of the side surface of the impeller blade on the discharge side, which passes through lightly touching the wall of the truncated cone, extends from the tip of the vane on the discharge side. , characterized in that the blade side surface extends over a relatively long distance to the point where it ends at the impeller boss.

This leaves a relatively large portion of the rear housing wall exposed and available for contact with the pumped fluid stream. As a result, the viscous fluid, which is difficult to pump by centrifugal action, adheres to the exposed portion of the stationary housing wall, and the side surfaces of the vanes on the discharge side create pressure in said viscous fluid towards the pump housing D discharge conduit. This fluid is pumped up by ensuring that the viscous fluid is displaced.

When the centrifugal pump according to the invention is used for pumping long fibrous suspended solids, the leading edge is... It can be formed as sharp shear edges that work together.

In this way, when the pump sucks in pieces of fibrous material that have wrapped around the blade, even if the blade side angle is relatively small, the fibrous material will move onto the blade side surface. The leading edge will slide toward the housing wall at the point where it merges with the boss. Said point on the leading edge of the vane rotates directly above the truncated cone of the no-uzing wall to guide the fibrous material through the opposite edge of the no-uzing wall,
Tear off fibrous substances by causing a new action.

In order for the centrifugal pump according to the invention to achieve completely favorable results,
The following extremely important angles - namely: the conical angle of the housing wall, the flank angle of the vane and the circumferential angle of the leading edge of the vane, the angle of the opposing edges on the housing and the angle of the shear line on the vane, etc. −1 can be varied within relatively wide limits.

” 'Near Si: / The cone angle of the wall and the flank angle of the blade may be within the range of 5° to 70°, and the circumferential angle of the leading edge may be within the range of 20° to 360° or more. It is fine as long as it is within.

The shear edge angle and the opposing shear line angle should not add up to 180°, unless they must both add up to 90". The angles are from 5° to 90°, respectively.
It is fine as long as it is within the range of the sword.

〔Example〕

Typical embodiments of the invention will be described in more detail with reference to the drawings.

The single-vane impeller of FIG. 1 has a conical boss 1 whose axis 1a is supported in a housing 2 (not shown in detail) and passes through a housing wall 3 on the discharge side of the pump. do. The housing wall 3 is in the form of a right truncated cone, with which the vanes 5 with their terminal edges 6 rotate in light contact with a very small gap 4 .

The angle of inclination ζ (theter) of the housing wall 6 with respect to the radial plane will be referred to here as the cone angle.

The housing wall 6, with which the blades 5 lightly contact, is provided with a milled recess 10 of wedge-shaped cross section, which extends spirally from the inside to the outside in the direction of rotation of the impeller. The radially inner edge 9 of this recess 10 is a fixed shear edge with an oblique angle δ (delta) around 1.

As shown in FIG. 3, the end side surface 7 on the discharge side of the blade 5 is
It has a flank angle ε (epsilon). This angle ε
In this state, the blade side surface 7 fuses with the leading edge 8 of the blade 5 at a point 7a. That is, at this point 7a, the leading edge 8 of the blade touches the boss 1
It is connected with.

As shown in FIGS. 4 and 5, the leading edge 8 of the blade is the limit of the blade side surface 7 on the discharge side and moves in light contact with the truncated right conical housing wall 3, but the tip of the blade is 8a4
The circumferential angle η (eta) extends over the entire area, and the terminal edge of the blade 6
passes through the step 6a and ends at the blade tip 8a.

The leading edge of the vane is formed as a sharp shear edge and, in cooperation with the opposite edge 9 of the housing wall 6, reaches the boss at an angle γ (gamma). The condition in this case is that the sum of the two angles δ and γ must not amount to a value of 180°; this is the only condition in which the cut strips can be simultaneously rejected and This is because it produces a pure stimulant effect.

Regarding the angles ε, η, etc., the following should also be noted. That is, the flank angle ε serves to cause the annular piece of fibrous material that reaches the flank 7 to slide out toward the discharge side, so it must be at least an angle of 5 degrees, but it should be approximately 15 degrees. A range from 40° to 40° is suitable.

For the angle ε, an angle of 30° has been found to be particularly suitable.

The same is true for the conical angle of the housing wall 6, i.e. for this angle too, values in the range from 15° to 40° are suitable; for the angle ζ, an angle of 30' gives good results in practice. I know that. In contrast, the circumferential angle η of the leading edge of the vane (between tip 8a and point 7a) ranges from about 20" to 36"
Any value between 0'' and 0'' can be taken in practice; however, a circumferential angle η ranging from 90' to 270° has proven particularly advantageous.

As is evident in the embodiments described above, relatively long pieces of fibrous material can also be used with the vanes always having a relatively slight slope in order to reach close to the cooperating shear edges 8 and 9. The fibrous material can be slid along the terminal edge 6 of the blade to the blade tip 8a, and instead, the fibrous material can be swept along the blade side surface Z on the discharge side to the leading edge of the blade. 8 directly towards a point 7a at the shortest radial distance, and once beyond this point 7a the piece of material is cut off by the opposite shear edge 9 of the housing wall.
Cut into small pieces.

Although the impeller may have to pass or rotate several times in order to completely shred the fibrous material, this process will ensure that the fibrous material pieces completely slide away from the end edge 6 of the impeller. occurs at a much earlier point in time than is necessary for

It may be appropriate to prevent this material from migrating as described above along the entire area of the end edge 6, which can be done, for example, by a step 6a in the blade end edge.
As shown in the drawing, this can be done just before the blade tip 8a.

As a result, a thin piece of fibrous material such as a ring of fabric, twisted yarn, and similar products can be prevented from moving to the O layer side of the impeller. There is also the risk that thin pieces of material may slip into the narrow gap 4 between the leading edge 8 and the housing wall 6 and become stuck in the impeller.

The impeller of the centrifugal pump shown in FIGS. 6 to 10 has a conical boss 21 with vanes 25 in the shape of a truncated cone, and the impeller shaft 66 is connected to the housing wall on the discharge side. 23. A housing wall 26 with a cone angle ζ between 5° and 70° is connected to the vane side 27 on the discharge side.
The leading edges 28 of the two pass in light contact with a very small gap 24 between them. This leading edge 28 spirals over a relatively long distance from the vane outlet tip 35 where the terminal edge 26 ends to a point 61 where the terminal edge 26 ends in a boss 21 having a relatively short radius r. As a result, over the relatively wide arc θ (theta) between the blade outlet tip 65 and the boss point 61, which is preferably between 30° and 90°, the nozzle wall 26 relatively large areas are exposed. The oozing wall can be exposed by reducing the impeller boss radius r to the extent that the impeller boss does not compromise the structural strength necessary to transmit force from the drive shaft 66 to the blades. .

A layer side layer that becomes visible between the blade side surface 27 on the discharge side and the blade side surface 69 on the suction side of the pumping conduit of the impeller.
As the width of the exposed portion of the housing wall decreases, it extends further toward the inlet portion of the impeller. This reduction in width in the direction of the impeller inlet occurs for reasons related to the strength and stability of the end portions of the blades.

Furthermore, for reasons of strength, the exposed portion of the housing wall in the pumping conduit of the impeller has an arc θ of, for example, 20”, calculated from the tip 35 of the end edge of the impeller; For the impeller configuration, an angular arc of up to 180° is acceptable, but according to the above instructions, an angular arc in the range 30° to 90° is preferred, since the front 28
Over a circumferential angle η ranging from 60° to 540°,
It means that you can grow.

A discharge opening 66 is located in the housing wall 23 near the drive shaft.
The gas is discharged and travels with the pumped medium. That is, this gas is discharged separately toward the rotation center of the impeller, and is also discharged on the discharge side of the impeller, so that it reaches the center of the housing wall.

The impeller boss 21 and the housing wall 26 further form a labyrinth between the exposed discharge side of the impeller and the interior 37 between the boss and the rear wall, in which a discharge opening 66 is formed.
is provided, so that any solid particles carried into the medium are unable to enter the discharge opening.

The labyrinth structure is further interrupted, at least on the side towards the housing wall (also on the boss side in FIG. 9), by transverse grooves 68 in order to provide a self-cleaning effect.

The foregoing text and drawings relate to embodiments of the invention which are presented by way of illustration and not by way of limitation, and it is understood that various other embodiments and modifications may be made within the spirit and scope of the invention. You should understand what you can do.

To summarize the disclosure of the present invention as follows, the oozing wall 26 through which the impeller shaft passes has a truncated conical shape.

The impeller on the discharge side of the pump rotates in light contact with this housing wall 23 with a very small gap.
extends in a spiral shape to a point 61 where it ends at a boss. As a result, a relatively wide portion of the housing wall 26, which has a width that becomes narrower toward the inside and is set between the side surface of the blade on the discharge side and the side surface of the blade on the suction side, is located at the blade outlet tip 65.
and this end point 61.

[Brief explanation of the drawing]

FIG. 1 shows the pump housing of a first basic embodiment of the invention in axial section and the impeller schematically. FIG. 2 is a plan view of the frustoconical Uzing wall of FIG. FIG. 3 is a side view of the impeller and frustoconical housing wall, with the outer housing cut away. Figure 4 is a plan view of the truncated conical housing wall O in the direction indicated by arrow A in Figure 3, with the front edge of the impeller 0 projected. 5 is an end view of the impeller of the pump shown in FIGS. 3 and 4, viewed in the direction indicated by arrow B in FIG. 3; FIG. FIG. 6 is an end view of the impeller of the second basic embodiment of the invention. FIG. 7 is a side view of the impeller, truncated conical wall, and DlI411 of the second basic embodiment, with the outside portion cut away. FIG. 8 is a plan view of the impeller of FIG. 6. FIG. 9 is an axial cross-sectional view taken through the impeller, frustoconical housing wall, outer housing, etc. of the second basic embodiment; FIG. 10 is a cross section taken along line CC in FIG. 9. 1. 21... Conical boss, 2, 22... No-Using, 6.26... No-Using wall, 4, 24...
Gap, 5, 25...Blade, 6, 26...Terminal edge, 6
a...Step, 7, 27...Blade side, 7a, 3
1... Point, 8, 28... Leading edge, 8a... Blade tip, 9... Radial inner line, 10... Hollow, 66...
... Drive shaft, 65 ... Impeller terminal edge tip, 66 ...
Discharge opening, 67... Inside between boss and rear wall, 38.
...Horizontal groove, 69...Side surface of the blade.

Claims (1)

[Scope of Claims] 1. The discharge end of the vane passes through the housing wall through which the impeller passes through, with a gap, in light contact, and the side surface of the vane on the pump discharge side is in contact with the housing wall. A centrifugal pump of the open type, especially for pumping viscous media, with a single impeller configured to terminate in front of the wall and with a leading edge extending between the tip of the blade end edge and the boss of the impeller. The nozzle wall (3, 23) is a right circular truncated cone, and the front edge (8, 28) of the side surface (7, 27) of the impeller blade on the discharge side has a gap (4, 24) with the truncated cone. The blade passes through the blade in light contact with the blade, and also extends over a relatively long distance from the blade outlet tip (65) to the point (7a, 61) where the blade side surface (7, 27) ends at the impeller boss (1, 21). An open type centrifugal pump with a single vane type impeller, characterized in that it is configured as follows. λ The leading edge (28) of the side surface (27) of the impeller blade on the discharge side has a circumference of a minimum of 360° and a maximum of 540° between the outlet tip (35) and the terminal point (61) of the boss (21). An open type centrifugal pump with a single vane type impeller according to claim 1, characterized in that the pump is configured to extend over an angle. 3 The side surface of the blade on the discharge side (27) and the side surface of the blade on the inlet side (3
9), the exposed portion of the housing wall (26) is between the impeller edge tip and the boss point (61).
Claim 2, characterized in that it is configured to extend over the entire range of at least 30°O arc (θ) between
Open type centrifugal pump with single vane type impeller as described in 2. 4. The discharge opening (36) for the gas coming out of the medium being pumped is located near the drive shaft in the
26) The open type centrifugal pump with a single vane type impeller according to any one of claims 1 to 3. 5. the impeller boss (21) and the housing wall between the exposed wall section and the inner part (67) formed between the boss and the rear wall and vented by the discharge opening (35);
23) forms a labyrinth, thereby preventing solid particles from entering the discharge opening. Open type centrifugal pump with single vane type impeller as described in 2. 6. The open type centrifugal pump with a single vane type impeller according to claim 5, characterized in that the labyrinth is configured to be interrupted by horizontal grooves (68) at least on the wall side. . 7. Patent claim for pumping suspended solids in the form of long fibers, characterized in that the leading edge of the side surface of the blade is configured to form a sharp shear edge that cooperates with the opposing shear line (9) of the oozing wall. An open-type centrifugal pump with a single vane impeller according to item 1. 8 The inclination angle (ε) of the blade side surface (7) on the discharge side and the cone angle (ζ) of the housing wall (3) are 15° and 4, respectively.
An angle between 0" is suitable, but an angle between a minimum of 5° and a maximum of 70° is not recommended. The circumferential angle (η) of the edge (8) is suitably between 90° and 270°, but 2
An open type centrifugal pump with a single vane type impeller according to claim 7, characterized in that the pump is configured to have an angle of 0" or more. 9. The leading edge of the blade (8) and this. Opposing shear edges (9)
9. The open centrifugal pump with a single vane impeller according to claim 8, characterized in that the sum of the appropriate acute angles (γ, δ) is not 180'. 10. The blade end edge (6) has a blade tip (8) on the discharge side.
Claim 9, characterized in that a step (6a) is provided immediately before a), so that the fibrous material piece cannot freely slide along the terminal edge. Open type centrifugal pump with single vane impeller.