The present invention relates to the field of machine-building industry and it can be used as an air compressor or a pump operating by conversion of gas energy into rotational energy and vice versa.

In the given field of technology, the so-called Liquid-ring vacuum pumps are known, in which liquid is contained in the cavity between the teeth of a rotary toothed gearwheel that is pressed against the inner surface of the housing of the pump by centrifugal forces. In this process, the fluid level in the cavity changes as a result of the change in the distance from the center of the toothed gearwheel to the surface of the housing, and the gas in this cavity is compressed and expanded. In this case, the liquid, which is poured by centrifugal forces into a uniform shape defined by the cavity, performs the function of a piston. Unlike a piston made of a solid material, such a liquid piston has the advantage that it creates an ideal sealing medium with the walls of the volume in which it moves and does not require the use of separate sealing means and complex systems for lubrication of the surfaces in contact. Due to this, the structure of the pump becomes simpler and cheaper, and its operation becomes easier. Therefore, liquid-ring vacuum pumps are widely used in the field of technology.

Despite the above, the efficiency of this type of pumps and the parameters of compression and expansion of the gaseous medium are relatively lower. There is no sealing between the teeth and the inner surface of the housing, and when the pressure changes between the teeth inside the cavity, the fluid flows intensively into and out of the cavity through the openings between the teeth and the housing. In addition to the fact that such inflows and outflows of liquid create a working moment on the toothed gearwheel, during the entire period of operation it is theoretically impossible for the liquid to flow into and out of the cavity without causing shocks, which naturally leads to losses. The jets of liquid exiting along the guide surfaces of the teeth move along the surface of the housing with different angular velocities and there are losses both between the jets with different radii and between the common jet and the surface of the housing. A classic double-acting liquid-ring vacuum pump is described in the source “ ponoB E.C. 1/i .qp. MexaHHMecKi/ie BaKyyMHbie Hacocbi. M.: MaLui/iHOCTpoeHi/ie, 1989 ^., page 166, Fig. 1066”,

According to the present invention, a liquid ring rotary vane device is provided that comprises a housing with an oval profile inner surface; a toothed gearwheel mounted on a shaft in the center of the housing, in the teeth of which there are slits in which spring- loaded plates are inserted that act as a sealing means against the inner surface of the housing as a result of their withdrawal from the slits; the toothed gearwheel is closed on both sides by flanges having on the inner side recesses into which the sides of the said plates are inserted, and holes connected with the compartments between the said teeth for the flowing the gas thereinto and flowing it therefrom, the device also includes a stationary gas commutator that comprises a plurality of chambers for gas and an end surface for sliding on the inner portion of the flange as the flange rotates together with the toothed gearwheel and for connecting the flange holes one-by-one with the gas commutator chambers.

The technical effect of the invention is increased efficiency.

The invention is explained with reference to the appended figures, wherein:

Fig. 1 shows a schematic representation of a the prior art liquid ring vacuum pump.

Fig. 2 shows a toothed gearwheel according to the present invention.

Fig. 3 shows a cross-section of a toothed gearwheel tooth.

Fig. 4 shows a sealing plate.

Fig. 5 shows a plug made of polymer.

Fig. 6 shows a flange.

Fig. 7 shows a gas commutator.

Fig. 8 shows the operation of the device according to the present invention in a pumping mode.

Fig. 9 (a-d) shows embodiments of the sealing means. Detailed description of the invention

Referring to fig. 2a , a toothed gearwheel 10 with teeth 11 having slits 12 is shown. Located between the teeth 11 are compartments 13. The toothed gearwheel 10 has a hole 14 in the center with a key slot for engaging a shaft (not shown in the figure).

Referring to fig. 3, a cross-section of a toothed gearwheel tooth is shown. A spring 40 and a plate 20 are placed in the tooth slit 12. The plate 20 is placed in the slit 12 with the capability of moving along the slide 30 inserted from both sides.

The slide 30 is made of an anti-friction material (preferably fluoroplast) and comprises a groove 31 for inserting a sealing plate 20.

When manufacturing the device according to the present invention, the springs 40 are inserted into the teeth slits 12 in advance, then the slides 30 and plates 20 are inserted. Referring to fig. 4, the sealing plate is shown. The sealing plate 20 has an upper horizontal edge 21 , a lower horizontal edge 22 and vertical lateral edges 23 (see fig. 4). These edges increase the plate's resistance to bending, thus making it possible to use a plate of relatively lower thickness and weight. The upper edge 21 is pressed to the inner surface of the toothed gearwheel. Its width is selected such that the pressure acting on the surface is reduced and the sealing is improved. The spring 40 acts on the lower edge 22 with a pressure force.

The plates with their ends are pressed against the inner surface of the housing, sealing the compartments between the teeth and when changing the distance from the center of the gearwheel to the surface of the housing, they are respectively pushed in or out of the tooth, forcibly changing the volume of the compartment. The liquid in the compartment under the action of centrifugal forces moves away from the inside of the compartment (closer to the center of the gearwheel) and fills the outer part, pressing against the inner surface of the housing. Its volume is chosen in such a way that the upper parts of the teeth, together with the plates, are always in the liquid. In the inner part of the compartment, when the volume changes, the gas is compressed or expanded. A forced change in the volume of the compartment allows it to be compressed to high parameters, and the absence of leaks between the teeth and the housing dramatically reduces losses, and thus the efficiency increases.

There are two types of liquid ring vacuum pumps - with a cylindrical housing that is shifted with respect the center of a toothed gearwheel; and the so-called double-action one, in which the internal section of the housing has an oval profile, and the toothed gearwheel is disposed in the center of the oval. According to the present invention, a double-action pump is preferrable because it has a higher efficiency with the same number of revolutions, and, at the same time, the forces acting on the toothed gearwheel are symmetrically balanced, which is why the load and vibration on the bearings of the structure are reduced. Nevertheless, when determining the oval curvature of the inner surface of the housing it should be taken into account that the radial acceleration of the change of the liquid level in each compartment increases twice with the same centrifugal acceleration. In order for the centrifugal forces to be able to collect the liquid in a single piston, it is necessary that the centrifugal acceleration always exceeds the radial acceleration of the liquid level in the direction of increasing radius. On the contrary, acceleration on the reduction of the level radius contributes to centrifugal forces.

The inner surface of the housing should be made preferably of a polymer material that has good frictional properties when lubricated with liquid and sufficient elastic deformation capability. In this case, when the upper edge of the plate is pressed against the inner surface, bending and sufficient sealing will occur. In the structure according to the present invention, preference is given to the housing made of a steel material, and the inner oval surface is created using a polymer plug having a predetermined curvature profile and is manufactured separately and then placed in the housing and fixed, for example by means of screws.

Fig. 5 shows said polymer plug 70.

A groove 71 is made on the lateral sides of the plug 70 to ensure sealing with the rotating flanges of the toothed gearwheel. Flanges (see Fig. 6) are provided for connecting the toothed gearwheel according to the present invention to a gas commutator (not shown in the figure), that are intended for supplying and outflowing gas between the toothed gearwheel compartments (windows). The flange 90 has a chamber 92 for liquid entry into the toothed gearwheel, that has a circumferentially decreasing cross-section, and holes 91 for mounting the flange on the housing, as well as a bearing (not shown) mounting area 93. In the process of operation, the flanges rotate together with the toothed gearwheel and alternately connect to the gas commutator chambers through their holes.

The use of flanges with ribs that cover the toothed gearwheel on both sides and rotate together with the gearwheel, makes it possible to abut the lateral sides of the sealing plate against the grooves on the inside of the ribs and significantly increase the resistance to bending of the plate (this may increase the pressure or reduce the weight of the plate), Fig. 7 shows a gas commutator.

The gas commutator has chambers in the form of cutouts 106 and 107. Sealing means are made on the outer radius 101 and on the inner radius 102. The commutator has also two holes 103 and 104 and two more holes on the opposite side. A liquid is supplied under pressure to the hole 103, and the hole 104 is connected to the chamber between the gas commutator and the ribs of the flange of the toothed gearwheel. The liquid is supplied through the hole 103 to the upper part of the compartment, and from the lower part of the window through the hole 104. Therefore, the compartment is filled with liquid after each cycle and liquid losses due to evaporation or leakage are compensated.

Fig. 8 shows the operation of the device according to the present invention in a pumping mode.

Fig. 8 for clarity shows a diagram 108 of filling the toothed gearwheel with liguid depending on the position of the compartment. Also for clarity shown in the figure are compartment windows 1 10, which rotate clockwise and are sequentially connected to the chambers of the gas commutator (not shown in the figure). In sector 1 , the compartment is filled with liquid until it is completely filled. In sector 2, the compartment windows are connect to the low-pressure chamber 106, wherein tha gas that is subject to compression enters. First, the lower part of the window (closer to the center) is connected, and then, following increasing in the distance of the liquid level from the center, the remaining upper part is connected. After reaching the maximum volume of the compartment, its window goes out of the connection zone with the low-pressure chamber and is plugged by the surface of the gas commutator. At the same time, in sector 3, the volume of the compartment decreases and the gas is compressed. After that, the window in the sector 4 is connected to the high-pressure chamber, and compressed gas is transferred to the chamber from the compartment. At the next stages, the compartment window moves to the opposite sectors 1 n,2n,3n,4n and the cycle is repeated in the opposite chambers of the gas commutator.

Fig. 9 (a-d) shows embodiments of the sealing means.

In fig. 9a, the sealing plate 151 is pressed against the inner surface of the toothed gerwheel by means of a spring-loaded plate 152 mounted on the bottom of a groove. The spring-loading of the plate is created by bending it along the groove or by bending its sheets along the groove or transverse to the groove. According to fig. 9b, instead of the spring-loaded plate, a rubber cord 154 with a round cross-section is placed, which presses the dealing means 153 to the surface due to the deformation of the crosssection. According to 9c, the rubber cord 155 itself plays the role of a sealer. Fig. 9d shows the self-sealing system. In this case, the pressure is distributed under the sealing plate 156 if there is a gap of sufficient size between the sealing plate and the wall of the groove 157 and the force acting on the plate from below exceeds the downward force from the distributed pressure across the sealed gap.

The selection of the materials of the sealing means is based on the parameters of the sealing environment. For liquid lubrication at low temperatures, fluoroplast, silicone or conventional rubber, kapron can be used. At higher temperature, at semi-dry gas-liquid lubrication, bronze, cast iron or chrome-nickel steel can be used. The device according to the invention is characterized by multi-functionality and depending on the construction of the gas commutator it can be used in various fields of technology, for example, as a pump with a high efficiency, in the form of a compressor or as a vacuum pump.