CN86102777A - The impeller that is used for rotary type fluid machine - Google Patents

Abstract

The present invention introduces a kind of impeller of centrifugal rotary machine, and it is applicable to that oil hydraulic pump also is applicable to gas compressor.Impeller has one to have disk and the many blades that is installed in wheel hub on the transmission shaft, they on circumference with evenly spaced apart and protrude along axial direction in a side of disk at least.The front of blade is adjacent the passage that defines fluid between the back of blade.Fluid passage its width of excircle direction from the wheel hub vicinity towards disk is to reduce gradually.The front-back of each blade comes down to be distributed on the arc surface with different curvature radius that same central point draws.The central point of each blade all be distributed in one with the concentric imaginary circle of circle disk center on.

Description

The impeller that is used for rotary type fluid machine

The present invention is relevant with the machinery of centrifugal rotating fluid, and this machinery can be used for oil hydraulic pump and also can be used for gas compressor; Say that more specifically the present invention is relevant with the blade wheel structure of the machinery of this class rotating fluid.

Gas, for example air is referred to as compressible fluid, and liquid, for example water is referred to as incompressible fluid.Compressor is to be used for compressible fluid, and pump is to be used for incompressible fluid, but their effect all is that the pressure of fluid is increased.Pump and compressor can pass to fluid with regard to its speed and make speed can be transformed into pressure energy this respect, and both working principles are identical.Yet the difference between compressible fluid and incompressible fluid makes these two kinds of fluid mechanics slightly different.The impeller of compressor is compared the number of its blade with pump more; The rotating speed of impeller can be 5000 rev/mins for instance, obviously is higher than the rotating speed of pump.When the speed of rotation of impeller is very high, just enough structural strengths need be arranged, to prevent because the damage of mechanical structure under high garden circular velocity and the big centrifugal action.

In this gate technique subject of pump, the traditional theory requirement of relevant centrifugal pump impeller is: two adjacent interlobate fluid passages are from the outlet near the import that is positioned at the impeller center portion all positions, garden outside being positioned at, its channel width should increase, but at U. S. Patent NO4,253,798 a kind of new design has been proposed after, thisly be counted as reliable conventional impellers structure always and assert it has been irrational by the present inventor, opposite with the impeller of conventional pattern, this newly-designed improvement impeller, the width of fluid passage from import towards outlet be reduce gradually and the degree of depth of passage is constant, this improved impeller is applied to prove on the pump that efficiency far surpasses conventional pumps.

Is is but the inventor extremely concerned about this actually newly-designed improvement impeller and whether also applicable to the compressor that has same rationale with pump? carried out experiment several times recently, from result of experiment, this improved impeller is the same with the occasion that is applied in pump, and desirable effect is arranged.Although the time limit of some experiments is shorter, but this validity has obtained proof, also finds, adopts the compressor of this improvement impeller can be subjected to mechanical damage after it uses the long duration, yet, find out that the reason that causes this mechanical failure is not difficult.Particularly, the improvement impeller that is used in the experiment is made by above-mentioned U. S. Patent, the radius of curvature of each blade front surface is less than the radius of curvature that is adjacent the blade rear surface, because the front surface centre of curvature is far away apart from the impeller center than rear surface The curvature center, the result be passage when fluid from import when exit width reduces, each blade from the center of impeller outward its thickness of garden Zhou Fangxiang but increase progressively, therefore, when rotor high-speed rotated, the mechanical stress of contiguous outer garden circumferential portion can increase to the degree of can not ignore.

The object of the present invention is to provide a kind of impeller that is used for fluid machinery, this impeller both can be used for gas compressor, also can be used in the oil hydraulic pump.Specific purposes of the present invention provide a kind of impeller that is used for centrifugal type fluid machine, and it can design by the theory that the inventor proposes and do further improvement, the survivability when having increased high speed rotating.

Another object of the present invention provides a kind of impeller of fluid machinery, little, the in light weight and available simple method manufacturing of its size.

Characteristics of the present invention are that the front surface of each blade and rear surface come down to be distributed on the cambered surface with different curvature radius of drawing from same central point, and each central point is positioned at the garden in an imaginary garden on week, and the garden heart in this imagination garden and the center of impeller overlap.Met above-mentioned condition, reduce gradually towards its width of the outlet that is positioned at impeller outer garden week from the import that is positioned near the impeller center by the front surface of each blade with formed fluid passage, the rear surface of its adjacent blades, the principle that has so just met the improvement impeller of present inventor's proposition, on the other hand, each blade is from being identical near the impeller center portion towards the outer garden of impeller its thickness of week.This just can be implemented in when reducing gross weight and make the distribution of weight reasonable, thereby avoid near the phenomenon of the mechanical stress concentration the week of impeller outer garden, such impeller just can be applicable in the very high gas compressor of rotational speed have the impeller blade of uniform thickness to be shaped with metal or synthetic resin manufacturing like that by the prior art narration.In these examples, the metal blade of uniform thickness can be with being weldingly fixed on the impeller plate, and impeller can be with various method manufacturings that are easy to realize such as casting, die forging, machinings.

But this impeller that has improved will be applied in the existing fluid machinery and to go, need to change slightly in design, but the correlation between relevant major parameter in the prior art and the performance still remains unchanged, thereby any modification can determine by rule of thumb, lists the relation of major parameter and performance below:

Impeller diameter: outlet pressure, rate of discharge and garden circular velocity.

Inlet diameter: air pocket

Draw the angle: outlet pressure and efficient.

Fluid passage number: rate of discharge and outlet pressure.

The sectional area of fluid passage: rate of discharge.

Fig. 1 is a kind of front view of fluid machine blade wheel made in accordance with the present invention;

Fig. 2 is along the cross-sectional view of 2-2 line among Fig. 1;

Fig. 3 is the key plan that shows the impeller blade among Fig. 1.

Consult Fig. 1 and Fig. 2, a kind of shown in the figure according to impeller example of the present invention, impeller 1 comprise one have wheel hub garden dish 2 and many equidistant blades 4 of being separated by on week in the garden, they are in axial direction protruding going on a side of garden dish 2.Example shown in the figure is unidirectional suction type, blade 4 is configured on the side of garden dish 2, should be appreciated that, the present invention also can be used for the impeller of two-way suction type, blade all is equipped with in two sides of corresponding garden dish, every blade 4 can be metal sheet profiled with the thickness uniformity of steel and so on, and make curve generating by giving fixed radius of curvature, and blade is fixed on a side of garden dish 2 with firm welding ground, and early oneself gives on the definite position of elder generation.The end-point distances wheel hub 3 of blade 4 has an interval of determining, this is in order to be defined as an inlet region 5 in the peripheral region around wheel hub 3, and another end points of blade 4 is stretched over the outer periphery of garden dish 2 always.Respectively be adjacent in the front 41 of each blade 4 between the back 42 of blade 4 and define fluid passage 6, the import 7 of passage 6 and inlet region 5 are communicated with, and export 8 outer periphery openings towards garden dish 2, all there is the identical degree of depth each fluid passage 6, that is to say that each blade 4 is contour with respect to garden dish 2, yet, the width requirement of fluid passage 68 reduces gradually from import 7 towards Way out, and the difference of width can be small certainly.Described example is the impeller that belongs to a kind of open type, a side that is each fluid passage 6 is opened wide, certainly in Fig. 2, dotting, just can constitute an enclosed impeller as long as add the side plate 9 of an annular, the wheel hub 3 of impeller 1 is installed on the transmission shaft 10 with method commonly used and fixes tightly with a tightening nut 11.

Fig. 3 has shown the position of each blade 4 on the impeller 1 shown in Figure 1, each identical parts item is ditto schemed among the figure, as can be seen, the front 41 of blade 4 and back 42 are distributed on the garden cambered surface with different curvature radius RF and RB separately, radius of curvature R F and RB draw from same center point P, between the back 42 of the front 41 of a blade 4 and the blade 4 that is adjacent, define fluid passage 6 like this, more particularly, the front 41a of a certain blade 4a and back 42a are distributed in separately from same center point P 1 and draw and radius of curvature is respectively on the garden cambered surface of RF1 and RB1, be respectively on the garden cambered surface of RF2 and RB2 and be distributed in the radius of curvature of drawing separately from another center point P 2 with the front 41b of blade 4a adjacent vanes 4b and back 42b, center point P 2 and above-mentioned center point P 1 depart from a segment distance, each center point P 1 and P2 are distributed on the imaginary garden R with the same garden heart, and the center C of this garden heart and garden dish 2 coincides.According to above-mentioned layout, the fluid passage that is limited between two adjacent blades just is tending towards reducing gradually towards its width of outlet 8 directions from import 7, the width of fluid passage 6 can be considered to signify a diameter that can be contained in the maximum imagination ball in the passage, in this, the basic functional principle of impeller 1 keeps identical with the U. S. Patent content that exemplifies above, thereby repeated description no longer.Yet according to the present invention, the curvature of each blade 4 is indeclinable, thereby all remains unchanged from the thickness that plays near the center portion of impeller away from the center portion blade of impeller, and this has just realized the balance of weight distribution on the dish 2 of garden.The zone forms excessive mechanical stress concentration garden week outside when high speed rotating to have avoided impeller, thereby this impeller both can be applicable to oil hydraulic pump and also can be applicable in the air compressor.

Claims (4)

1, a kind of impeller that is used for rotary type fluid machine, it includes a garden dish that has wheel hub, and wheel hub is fit to be installed on the transmission shaft; Many blades evenly distribute with the interval that equates on the week of impeller garden and protrude along axial direction in a side of garden dish at least, each blade has a front and back and by the front of a blade be adjacent the passage that limits fluid between the back of blade, the zone that these fluid passages distributed is the outer garden week that always extends to garden dish body around wheel hub, the fluid passage reduces gradually near outer its width of garden Zhou Fangxiang towards the garden dish wheel hub, but the degree of depth remains unchanged.

The characteristics of this impeller are, on the garden cambered surface that has different curvature radius respectively that the front-back of each blade comes down to draw from same central point, each central point all be distributed in one with the concentric imaginary garden of dish garden, the garden heart on.

2, be applicable to oil hydraulic pump by the described impeller of claim 1.

3, be applicable to gas compressor by the described impeller of claim 1.

4, by the described impeller of claim 1, each blade can be shaped with the sheetmetal manufacturing of uniform thickness, and blade adopts welding method to be fixed on the dish of garden.

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