RU2184875C1 - Guide vane pump - Google Patents

Abstract

FIELD: chemical and oil producing machinery, different branches of industry where forced delivery of liquid is required. SUBSTANCE: invention relates to rotary pumps. Proposed guided vane pump has housing with suction and discharge ports and end face covers. Rotor installed inside housing is provided with rectangular vanes fitted in radial slots of rotor on end face surfaces of which bevels are made at acute angle α to plane of end face covers. Bevels begin on circumference located at distance 1 from hub surface. Value of 1 is calculated by formula l = (1,00-1,10)h $\genfrac{}{}{0ex}{}{\text{max}}{\text{v}}$ where 1 is distance from rotor hub surface-lower edge of slots to circumference on which bevels begin, mm; h $\genfrac{}{}{0ex}{}{\text{max}}{\text{v}}$ is maximum projection of vane from slot at moment of movement of vanes along lower member from suction space to discharge space, mm. EFFECT: provision of 3-5% increase of [ump efficiency. 2 dwg

Description

 The present invention relates to hydraulic engineering, in particular to rotary pumps, and can be used in various sectors of the economy as mobile and stationary pumping units for pumping liquids with mechanical impurities during discharge and loading operations.

 In pump engineering, water ring and vortex pumps are known (A.S. USSR 397676, M. cl. F 04 C 7/00, 1971, [1]), which allow the pumping of various liquids, including with mechanical impurities. In the known pump, the rotor and the blades have a trapezoidal profile and are made as a whole, which does not allow to obtain a pump efficiency above 25-38% due to volumetric losses at the ends between the housing and the rotor.

 A technical solution is also known (US patent 3480203, N. CL. 418-119, 1969, [2]), in the compressor of which, above the hub, the rotor is made in cross section in the form of a trapezoid, around which there are two plates having bevels along the slope of the trapezoid and springs that move the plates to the walls of the housing, which creates the possibility of rotation from the crankshaft and the movement of compressed air through a conical gap formed by the trapezoid of the rotor and the bevels of the plates.

 In the well-known technical solution (compressor) for the production of compressed air adopted a complex design, unreliable for pumping liquids.

 From the patent literature known volumetric hydraulic machine by.with. USSR 1137244 cells F 04 C 2/344, 1982, [3]. In a known solution, the peripheral part of the end surfaces of the rotor is made spherical. This design creates the conditions for the skew of the shaft due to one-sided axial inlet and outlet of fluid through the channels in the distribution disk. The pressure difference in the inlet and outlet sections creates an axial force, which presses the rotor against the machine body, and the moment bending the shaft. In addition, the profile of the end surfaces of the rotor, creating a gap, requires the use of special equipment (templates, guides, etc.).

 Closest to the proposed invention and taken as a prototype is a vane pump according to as USSR 1735608, F 04 C 2/344, 1992, [4] comprising a housing, end caps, a rotor with radial grooves in which rectangular plates are mounted, bevels are arranged on the end surfaces of the rotor axially above the hub at an acute angle α relative to the plane of the end caps. The beginning of the bevels, located on a circle equal to the depth of the groove, forms enlarged end gaps on the outer diameter of the rotor and minimal on the circumference.

 The disadvantage of this pump (a.s. 1735608) is the relatively low efficiency due to the presence of volumetric losses due to fluid flow in the lower part of the rotor grooves (at the depth of the groove).

 The fluid flow occurs at the maximum exit of the plates in the radial grooves through the enlarged end gap from the inner surface of the groove to the inner end of the plate and the groove opened in this place.

 The technical result of the invention is to increase the efficiency of the pump.

The specified technical result is achieved by the fact that in the well-known vane pump containing a housing with suction and discharge windows and end caps, in the inner cavity of which a rotor is installed, rectangular plates placed in radial grooves of the rotor, on the end surfaces of which are beveled at an acute angle α to the plane of the end caps, while the beginning of the bevels is located on a circle, according to the invention, the circle is removed from the surface of the hub by a distance l, determined by the following formula:
l = (1.00-1.10) h ^max _pl ,
where l is the distance from the surface of the hub to the beginning of the bevels, mm;
h ^max _PL - the maximum exit of the plate from the groove at the moment of movement of the plates along the lower trap from the suction cavity to the discharge cavity, mm

In the vane pump, an increased end gap between the end caps and the side surface of the rotor along the outer diameter (δ _max ) is obtained and the gap (δ _min ) is left unchanged from the surface of the rotor hub to the end surface of the rotor at a distance (1) corresponding to the position of the lower end of the rectangular plates at their maximum exit from the groove before touching the inner working surface of the housing.

 In FIG. 1 shows a vane pump (sectional view); figure 2 - vane pump (section aa).

The vane pump consists of a housing 1 with suction and discharge windows 2, 3, a rotor 4 with radial grooves 5 into which rectangular plates 6 are mounted, bevels made at an axial section above the hub 7 at an axial cross-section, located at an acute angle α relative to the plane end caps 8 9. Starting bevel arranged on a circle at a distance (1) corresponding to the position of the lower end plate 6 at their maximum h ^max _Sq output from the groove 5. The bevels form an enlarged δ _max Mechanical clearance between the rotor 4 and the small cial δ _min between the rotor and the inner surface 9 of covers.

To explain the pump, the following conventions are introduced: D - outer diameter of the rotor 4 of the vane pump, mm; α is the acute angle of the bevel of the end (side) surface of the rotor 4 relative to the plane of the end caps 9, degrees; δ _max - the maximum lateral (end) clearance along the outer diameter of the rotor 4 between the end surfaces of the rotor 4 and the lateral planes 8 of the end caps 9, mm; δ _min - the minimum lateral (end) gap between the end surfaces of the rotor 4 and the planes of the end caps 9, mm; 1 - distance from the surface of the rotor hub (lower edge of the groove) to the circumference of the beginning of the bevels (to the lower end of the plates at their maximum exit from the groove), mm.

Thus, the essence of the invention is that in the vane pump on the end surfaces of the pump rotor 4, bevels are made at an acute angle α relative to the plane of the end caps 9. The beginning of the bevels (points a and b of Fig. 2) is located on the circumference remote from the hub 7 to a distance (1) corresponding to the position of the lower ends of the plates 6 at their maximum output h ^max _PL from the groove 5, which allows to obtain an increased clearance (δ _max ) between its end surfaces and the surfaces 8 of the end caps 9 by the outer diameter of the rotor 4 left I minimum value of end of gaps (δ _min) between the end surface of the rotor 4 to the beginning of the bevel (the point "a" and "b" of FIG. 2) from the rotor hub. Having obtained an increased clearance δ _max in the proposed pump, the authors, by optimizing the start point of the bevels, managed to maintain a minimum clearance along the entire lateral surface of the plates 6, which increased the reliability and durability of the pump and at the same time the pump efficiency.

The vane pump operates as follows. When the rotor 4 rotates in the direction of the arrow, the volume of the cavities is limited, limited by the inner surface of the housing 1 by two adjacent plates 6 and the end caps 2 and 3, as a result of which a vacuum is created in the suction cavity and the fluid moves to the injection cavity. The upper contactor from point C to point K and the lower contactor from point E to point F, along which the working ends of the plates 6 slide, separate the pump cavity into the suction and discharge cavities. When moving the plate 6 to the lower contactor (point E), the plate moves in the radial groove 5. Over the entire section of the lower contactor from point E to point F, the plate 6 has a maximum displacement (h ^max _PL ) from the groove 5. Considering that the plates 6 moving in grooves 5 of rotor 4, they remained unchanged in a rectangular shape, and the center of the bevels shifted, the hydraulic indicators of the pump did not change, because volume losses are reduced due to the fact that the bevels on the end surfaces of the rotor 4 are carried out in the pump on a circle corresponding to the grooves 5 constantly closed by the moving plates, and the minimum end clearances are made below the bevels in the direction of the hub 7.

Mechanical impurities that accumulate under the action of centrifugal forces on the periphery of the rotor, due to the increased clearance δ _max, do not create mechanical damage to the working end surfaces of the rotor 4 and the covers 9.

As shown by tests of a prototype vane pump (see table), a change in the position of the beginning of the bevel on the end surfaces of the rotor by an amount (1) equal to the maximum output of the plate h ^max _pl allows increasing the pump efficiency by 3-5%.

Sources of information
1. USSR author's certificate 397676, M. cl. F 04 C, 7/00, 1971.

 2. US patent 3480203, N. cl. 418-119, 1986.

 3. Copyright certificate of the USSR 1137244, cl. F 04 C, 2/344, 1982.

 4. Copyright certificate of the USSR 1735608, cl. F 04 C, 2/344, 1992 (prototype).

Claims (1)

A vane pump containing a housing with suction and discharge windows and end caps, in the inner cavity of which a rotor is installed, rectangular plates placed in radial grooves of the rotor, on the end surfaces of which are beveled at an acute angle α to the plane of the end caps, while the beginning of the bevels is located on a circle, characterized in that the circle is removed from the surface of the hub by a distance l, determined by the following formula:
l = (1.00-1.10) h $\genfrac{}{}{0ex}{}{\text{max}}{\text{pl}}$ ,
where l is the distance from the surface of the hub of the rotor - the bottom edge of the grooves to the circumference of the beginning of the bevels, mm;
h $\genfrac{}{}{0ex}{}{\text{max}}{\text{pl}}$ - the maximum exit of the plate from the groove at the time of movement of the plates along the lower trap from the suction cavity to the discharge cavity, mm

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