WO2015104597A1

WO2015104597A1 - Trochoidal pump

Info

Publication number: WO2015104597A1
Application number: PCT/IB2014/066697
Authority: WO
Inventors: Станиславс МИРОПОЛЕЦС; Павелс МИРОПОЛЕЦС
Original assignee: Станиславс МИРОПОЛЕЦС; Павелс МИРОПОЛЕЦС
Priority date: 2014-01-07
Filing date: 2014-12-08
Publication date: 2015-07-16
Also published as: LV15039A; LV15039B

Abstract

The invention relates to hydraulic and pneumatic pumps having an operating rotor, which can be used for pumping liquid and gas between vessels or for supplying liquid and gas for cooling, lubrication and hydraulic driving purposes, particularly in internal combustion engines (fig. 1). The ability to achieve enhanced performance and efficiency relative to toothed pumps and vane pumps of identical dimensions and mass is achieved in that the present pump utilizes a novel design which includes a shaped sleeve, in which an actuating camshaft with a shaped piston are positioned. A change in the direction of rotation of the shaft changes the direction in which the liquid or gas is pumped.

Description

TROCHOIDAL PUMP

Technical field

The invention relates to mechanical engineering and can be used for power drive, cooling and lubrication systems serving various mechanisms, in particular engines, as well as for pumping liquid and gas between containers.

State of the art

Toothed and vane pumps are widely used in mechanical engineering [1, 2]. Trochoid pumps, in which the shaped profiles of the working surfaces are formed by trochoid fragments, are numerously represented in private inventions. Their main disadvantages are as follows: productivity and volumetric flow rate are limited by the permissible height of the teeth and blades; partial reverse return of the injected substance between the teeth of the interacting wheels reduces the efficiency of the pump.

Disclosure of the invention

The purpose of the invention is to increase the efficiency of the pump, reduce the size, weight and provide the following advantages: simplicity of design lack of ripple; ability to work at low and high pressures; the possibility of constructive refinement to obtain feed control.

The purpose of the present invention is achieved by using a cam shaft with a piston of a hyprochoidal profile placed inside the sleeve into the cavity of the epitrochoidal profile. These structural improvements, combined with well-known designs, include the following. The sleeve from the ends is closed by covers and inserted into the case in the form of a shell with inlet and outlet fittings. The covers are the supports of the cam shaft, through one of them the shaft shaft protrudes outward, allowing rotation in both directions to change the pumping direction. The processes of suction and discharge occur due to the fact that the contact lines of the piston with the sleeve divide the internal space into 4 variables with respect to the volume of the cavity. When the shaft and piston rotate, the cavities are connected to the suction fitting at the time of expansion, sucking in liquid or gas, and with the pumping nozzle, at the time of reduction, squeezing them out. Stable pumping occurs.

Brief Description of the Drawings

The following figures show the following:

figure 1 - the device of the pump in longitudinal section;

figure 2 is a view of the device along arrow A in figure 1;

FIG. 3 is a cross-sectional view of the device along line BB in FIG. 1;

figure 4 - projection sleeve 1 in figure 1.

In accordance with the above structural and functional principle, the device of the main components and parts of the pump is made as follows.

The sleeve 1 (Fig. 1, 3, 4) is a device in which the rotary pumping mechanism is located. The outer surface of the sleeve is stationary in contact with the inner surface of the shell of the housing 3 and has five surface grooves: three for the seals 14, and two are communication channels 17 and 17 'of the same pressure cavities inside the sleeve through four channel openings 18 and 18'. Grooves are allowed to be made on the body. The distance I between the communication channels should be equal to the distance between the holes in the housing under the fitting. At the ends of the sleeve have threaded bores for fastening the covers and b 7. Inside the sleeve done through a longitudinal passage 19, the cross-sectional contour of which is an outer part epitrochoid as a closed polygonal line curve with two axes of symmetry of the long L, = 14e and short _e = 1 10th. Curve formulas in rectangular coordinates:

X— - (24 sin r + 25 sin 3τ), Υ = - (24 cos t + 25 cos 3s),

where the free parameter is τ = 0, ..., 2π. A slip curve is rolled in from the inside by a hypotrochoid of the piston during shaft rotation. From both ends of the sleeve, the passage 19 is bored from the inside to a diameter d ₁₉ > 14e for centering the covers b and 7. The nominal length L _i9 between the inner ends of the sleeve should be equal to the length C of the piston 2.

The angle φ between the axes of the channel openings 18, 18 'and their diameters must be selected so that the holes are located closer to the small horizontal axis of the epitrochoid, but do not intersect it.

The piston 2 (Fig. 1, 3) has an axial longitudinal hole for landing on the cam 5 of the shaft directly, but movably or through sliding and rolling bearings. In the first case, the piston or cam shaft should be made of appropriate anti-friction material, such as bronze, etc. The piston cross-section curve profile is a closed hypotrochoid curve with three vertices and a radius of the circumscribed circle R ₂ = бе. This is the Ryelo triangle.

Curve formulas in rectangular coordinates:

X = e (5 sin r - sin 2τ),

Υ = e (5 cos τ + cos 2τ).

The housing 3 (Fig. 1, 2, 3) may consist of a sheet sheath covering the outside of the sleeve, and two bosses 16 welded hermetically to the sheath, one above each communication channel 17 and 17 'of the sleeve. Channels are allowed to be made on the case. The bosses have through threaded holes for connecting the fittings 15 and 15 '. The distance I between the axes of the holes should be equal to the distance between the communication channels on the sleeve. The housing can be made integral with fittings.

The shaft 4 (Fig. 1, 3) contains sections with different sizes of the outer surfaces. The output section is supported on the through cover b through the bearing or the flange 8. The middle section serves for a fixed fit of the cam 5. The inner end section of the shaft rests on the Central part of the blind cover 7 through the sliding bearing 9 or rolling. The outer end section is used to connect the power drive. The configuration of this section may be different depending on the known connection methods: keyed, gear, through a polyhedron, etc. The shaft can be made as one integral part with a cam 5.

Cam 5 (Fig. 1, 3) is made in the form of a cylinder with a longitudinal hole d ₅ . The longitudinal axis of the hole is offset from the axis of the large cylindrical surface with a diameter of D ₅ by an eccentricity e, which determines the parameters of the piston hyprochoid and sleeve epitrochoid. A piston 2 is movably mounted on a surface with a diameter of D _5. The cam length must be less than the piston length L ₂ .

Caps b and 7 (Fig. 1, 2, 3) serve to center the shaft relative to the liner and to limit the longitudinal displacement of the piston. The end face of the piston should freely, but without gaps, end the piston end. This inner part of the cover is inserted into the end bore of the sleeve, centering it, and has a groove under the seal 13 on the centering surface. Simple fixing holes are placed on the covers opposite the threaded holes on the ends of the sleeve. The covers differ only in the central part. In the through cover b there is a central hole for accommodating the bearing or flange 8 under the shaft outlet and threaded holes for mounting the flange. In the blind cover 7 there is a central recess for the rolling or sliding bearing 9 of the shaft 4.

Flange 8 (Fig. 1, 2) serves as a support for the outgoing part of the shaft. It has a Central hole with a groove for the seal 11. On the cylindrical surface of the flange embedded in the Central hole of the cover b, there is a second groove for the seal 12. On the flange there are simple mounting holes opposite the threaded holes of the cover b. The flange material is anti-friction.

The sliding bearing 9 (Fig. 1) has a central hole machined by the diameter of the shaft support portion, an outer surface pressed into the blind cover 7, and a protruding belt limiting the insertion depth near the end.

The sealing washer 10 (Fig. 3) with the outer and inner diameters machined by fittings 15, 15 'and the boss 16, are made of material resistant to the pumped substance. O-rings 11, 12, 13, 14 (Fig. 1) - from a cord with a round or other cross-sectional profile. The seal material is resilient and resistant to the pumped substance. Seals are placed on the corresponding parts in the grooves and are designed for tight contact of the parts: 11 - movable relative to each other and 12, 13, 14 - stationary. When the parts are precisely adjusted to each other, some of the above seals may not be used.

The fitting 15 and 15 '(Fig. 2, 3) is selected as a finished product for pump performance. The fittings can be integral from the housing 3, for example, welded.

Based on the detailed design of the device described above, the sequence of the pump is described below.

Take the initial position of the pump shown in FIG. 3, taking into account the following data:

- one of the vertices of the piston C is vertically in the upper position;

- the shaft with the piston rotates at a constant speed P _v l clockwise;

- on the theory trochoidal gearing ratio of the piston and shaft speeds equal to: f pw _ON / n _{wa / 1} = 1/3;.

- pumped substance - liquid.

At any moment in time in the cross-section of the device, the piston has at least four points of contact with the sleeve, which divide the space between the piston and the sleeve into variables by volume of the part.

By turning the shaft 4 and the cam 5 by the angle a in the clockwise direction the piston 2 assumes the position 2 _and shown in thin lines, turning around its axis at an angle oc / 3. In this case, a fluid is displaced from the cavities M, m, which, through the channel openings 18 and the circumferential communication channel 17 (located behind the channel 17 '), enters the right-hand discharge fitting 15. At the same time, the cavities N and n expand, sucking the liquid through the other channel openings 18' and another circumferential communication channel 17 'from the left suction fitting 15'. With further rotation of the shaft and piston, this fluid is displaced into the right discharge fitting as described above at the beginning of the process. Such pumping of fluid occurs continuously when the shaft rotates in any position of the piston. When the shaft rotates 4 in in the opposite direction - counterclockwise, the above fluid flow changes direction and pumping will occur in the opposite direction.

Obviously, in one revolution, the presented pump sucks in and further squeezes out more liquid (approximately twice) than with gears of the gear pump, conventionally inserted into the internal dimensions of FIG. 3 (due to limited tooth height).

The ability to obtain greater productivity and efficiency compared to gear and vane pumps with the same dimensions and weight is achieved by the fact that this pump uses a new design that includes a figured sleeve, inside which a drive cam shaft with a figured piston is placed.

Bibliography

1. Gear hydraulic machine - Wikipedia.

2. T.M. Bashta, S. S. Rudnev, B. B. Nekrasov et al. Hydraulics, hydraulic machines and hydraulic drives. M: Engineering, 1982.

List of symbols (positions) of elements in figures

1 - sleeve; 12 - a sealing ring;

2 - the piston; 13 - a sealing ring;

3 - case; 14 - a sealing ring;

4 - shaft; 15 - discharge fitting;

5 - cam; 15 '- - suction fitting;

6 - through lid; 16 - - boss;

7 - cover is deaf; 17 - - high pressure communication channel;

8 - flange; 17 '- - communication channel low pressure;

9 - bearing; 18 - channel channel high pressure;

10 - - sealing washer; 18 '- channel hole low pressure;

11 - - a ring sealing; 19 - passage in the sleeve.

Claims

CLAIM

1. A trochoidal pump comprising a housing with two fittings, an internal pumping mechanism with a shaft and two covers, characterized in that the covers mounted on the ends of the housing are machined along the inner end for sliding contact with the piston, and a girdle for centering relative to the sleeve is grooved from the end, and in the center they have a hole under the shaft support.

2. The pump according to claim 1, characterized in that the casing is made as a shell covering the surface of the sleeve, covering the grooves in it, and having bosses with threaded holes for mounting the fittings over the channels.

3. A pump according to any one of the above paragraphs, characterized in that the shaft has a cylindrical cam for movable seating of the piston with an eccentricity e to the axis of the shaft and an outlet portion connected to the rotation drive.

4. A pump according to any one of the above paragraphs, characterized in that the main part of the pumping mechanism is a piston having flat ends for sliding contact with the ends of the covers, a central hole for movable seating on the shaft cam and an outer surface formed by a hyprochoid with formulas in rectangular coordinates:

X = e (5 sin τ - sin 2τ),

Υ = e (5 cos τ + cos 2τ),

where the free parameter is τ = 0, ..., 2π.

5. A pump according to any one of the above paragraphs, characterized in that a sleeve is placed inside the housing, in which central recesses with a diameter greater than 14e are machined from the ends to introduce centering parts of the covers, the outer surface has a cylindrical or other shape with grooves for seals and for channels connection, and in the body of the sleeve two channel openings were made to each communication channel from the inner passage, the cross-sectional profile of which is a broken epitrochoid curve with the formulas:

X— - (24 sin r + 25 sin 3τ), Υ = - (24 cos m + 25 cos 3m).