WO2012023916A1

WO2012023916A1 - Rotary piston compressor

Info

Publication number: WO2012023916A1
Application number: PCT/UA2011/000059
Authority: WO
Inventors: Максим Викторович ОЛЕНИЧ; Борис Георгиевич НЕХОРОШЕВ
Original assignee: Olenich Maksim Viktorovich; Nechoroshev Boris Georgievich
Priority date: 2010-07-28
Filing date: 2011-07-26
Publication date: 2012-02-23
Also published as: UA104999C2; KR20130092568A; EP2647846A1; RU2013106968A; CN203321830U; EP2647846A4; RU2535307C2; CN203641013U

Abstract

The invention is concerned with the field of constructing compressors and can be used in stationary and portable gas (air) and refrigerating plants, air-conditioners and heat pumps. A rotary piston compressor is proposed, the compressor comprising an epitrochoidal body with a front and a rear lateral cover and with a rotor which is arranged in the cavity of said body and is situated on an eccentric shaft, wherein the body, lateral covers and rotor form variable-volume working chambers, a system for lubricating the working surfaces of the compressor, the system having a lubricant-containing housing, a device for atomizing the lubricant in the form of an ejector, the nozzle of which is connected by a pipe to the bottom part of the housing, a system of channels connecting the ejector to the working chambers, and a device for metering the supply of lubricant, in which the lubricant-containing housing is fastened to the rear lateral cover, the ejector is mounted within the housing, and the channel system is in the form of a radial or inclined opening, which is formed in the expansion zone in the body, and an axial opening which is connected to said opening via a large-diameter chamber and passes through the body, the flange of the rear lateral cover and the front flange of the housing, and is connected to the ejector, and radial channels are formed on the working surfaces of the lateral covers in order, via an annular gap formed between the eccentric shaft and rear lateral cover, to connect the housing cavity to the working chambers in the suction period, wherein the device for metering the supply of lubricant is in the form of a spring-loaded valve and slotted flexible ring, primarily made of anti-friction material and having a gap of a specified metering size at the location of the slot, of which valve and ring the spring-loaded valve is mounted in front of the ejector in the above-mentioned large-diameter chamber, and the slotted flexible ring is mounted in the annular gap between the eccentric shaft and rear lateral cover, wherein said annular gap is covered by the ring and the gap of a specified metering size is formed at the location of the slot of said ring. The compressor additionally comprises, within the housing, an additional backup lubricant-spraying means in the form of a pair of gears mounted in the housing.

Description

Rotary piston compressor

The invention relates to the field of compressor engineering and can be used in stationary and transport gas (air) and refrigeration units, air conditioners and heat pumps.

The advantages of rotary piston compressors over reciprocating compressors are the absence of elements with reciprocating motion, which allows to provide good specific indicators in terms of mass and dimensions, reducing the level of vibration and noise.

A rotary piston compressor is known comprising an epitrochoid housing with front and rear side covers and a rotor located in its cavity located on an eccentric shaft, while the housing, side covers and rotor form working chambers of variable volume, a lubrication system for compressor working surfaces containing an oil tank for lubricant content, a lubricant spraying device in the form of an ejector, the nozzle of which is communicated by a tube with the mentioned oil tank, and a system of channels made in an eccentric shaft and connecting the ejector to working chambers (A.S. USSR L 315800, publ. 10/01/1971, bull. N ° 29).

The specificity of rotary piston compressors is that, due to the lack of space for efficient rotor mechanical seals and the difficulty of removing oil from it, the simplest and most reliable way to prevent its excessive quantity entering the working chambers is to dispense its supply.

The disadvantages of the known rotary piston compressor:

1. No dosing of the amount of oil supplied.

2. Since the ejector is constantly connected to the working chambers and the oil tank, an excess, uncontrolled amount of oil is sucked in through it during suction, which, due to the previously noted specificity of rotary piston compressors, is for the most part discharged into gas (air) rotary piston compressors into the atmosphere, worsening ecology, increasing the loss of oil from the system, leads to increased carbon formation, especially in the discharge valve.

3. Additionally, an oil tank is required that is not structurally included in the compressor located outside it, as well as an ejector with oil lines. At low ambient temperatures, which reach up to minus 55 ° С under operating conditions, the oil thickens so much that without its forced heating in the oil tank by unauthorized persons the source of heat, the ejector (and, perhaps, of a different type of pump) cannot suck it from the oil tank and give it to the consumer.

4. The ejector works only in the presence of a certain pressure drop, while in operation it can be (significantly) lower, for example, when performing sandblasting, painting and other work, in which the ejector does not work.

5. The ejector is made of pipes with a small outer diameter - about 8..10 mm, and since they are located outside the compressor, they can easily be damaged (broken) during transportation and operation of the compressor.

6. Installing an ejector in front of the front end of the shaft eliminates (or greatly complicates) the possibility of installing an impeller for the impeller on it.

Also known is a rotary piston compressor containing an epitrochoidal housing with front and rear side covers and a rotor located in its cavity located on an eccentric shaft, while the housing, side covers and rotor form working chambers of variable volume, a lubricating system of compressor working surfaces having a crankcase for the content of lubricant, a device for spraying lubricant in the form of an ejector, the nozzle of which is communicated with a tube to the bottom of the crankcase, a system of channels connecting the ejector to the working chambers, and a device for zirovaniya supplying lubricant into the axial bore of the eccentric shaft (AS USSR JsTe 1231263, publ. 15.05.1986, Bul. 8, prototype).

This compressor partially eliminated the first of the above disadvantages, namely, at the inlet to the radial drilling of the eccentric shaft, a dispenser is installed in the form of a rotary damper with an actuator equipped with a time relay, which reduces the amount of gas-oil mixture supplied to the shaft during the expansion process.

However, this dispenser complicates the design and reduces the reliability of the compressor.

In addition, it has the remaining disadvantages listed above.

The basis of the invention is the task of creating a rotary piston compressor, in which by changing the location of the ejector and switching the channels of the lubrication system, as well as introducing new structural elements, an economical metered supply of lubricant to the rubbing surfaces of the compressor is provided.

The problem is solved in that in a rotary piston compressor containing an epitrochoid casing with front and rear side covers and placed in its cavity by a rotor located on an eccentric shaft, while the housing, side covers and rotor form the working chambers of variable volume, the lubrication system of the compressor working surfaces having a housing for lubricant, the lubricant spray device in the form of an ejector, the nozzle of which is communicated with the bottom of the tube part of the crankcase, a system of channels connecting the ejector to the working chambers, and a device for dispensing a lubricant supply, according to the invention, the channel system is implemented as a radial or inclined hole I, made in the housing in the expansion zone, and connected to it through a larger diameter chamber of the hole passing axially through the housing, the flange of the rear side cover and the front flange of the crankcase, and connected to the ejector, and radial channels are made on the working surfaces of the side covers for connections through an annular gap formed between the eccentric shaft and the rear side cover, the crankcase cavities with the working chambers during the suction period, and the device for dispensing the lubricant supply is made in the form of spring-loaded of the valve and the split elastic ring, mainly of antifriction material, having a gap of a predetermined dosing quantity at the section of the cut, of which, a spring-loaded valve is installed in front of the ejector in the aforementioned chamber of a larger diameter, and the split ring is installed in the annular gap between the eccentric shaft and the rear side cover, moreover, this annular gap is closed by an elastic ring and a gap of a predetermined dosing quantity is formed in the place of its cut.

A buffer volume is made above the spring-loaded valve.

The split ring can be installed both in the annular groove made in the hole of the rear side cover and in the annular groove made in the body of the eccentric shaft.

The problem is also solved by the fact that in a rotary piston compressor containing an epitrochoid casing with front and rear side covers and placed in the formed casing and cavity covers by a rotor located on an eccentric shaft, the casing, side covers and rotor form working chambers of variable volume , a compressor working surface lubrication system having a crankcase for containing lubricant, a lubricant spray device in the form of an ejector, the nozzle of which is communicated with a tube to the bottom of the crankcase, a duct system Connecting the ejector with the working chambers, and a device for dispensing lubricant feed according to the invention installed in the crankcase lubricant spraying additional means formed as a meshed driving and driven gear, while the drive gear is rigidly fixed to the eccentric shaft, and the axis of the driven gear is fixedly mounted in the lower part of the rear side cover so that part of this gear is located below the lower mark of the lubrication level.

The implementation of the compressor in accordance with the proposed invention provides the following advantages:

The proposed compressor provides more accurate dosing of the amount supplied to the rubbing parts of the working chambers of oil.

During suction, the necessary and controlled amount of oil is sucked in. Therefore, its emission into the atmosphere is reduced to a minimum, and carbon formation is reduced. There is no need for an oil tank, because the crankcase is structurally included in the compressor. At low ambient temperatures, oil is heated from the rear side cover of the compressor. Despite the fact that the ejector works only in the presence of a certain pressure drop, and in operation it can be (significantly) lower, for example, when performing sandblasting, painting and other works, in which the ejector does not work, however, the lubrication system also works , since the oil is sprayed by an additional, duplicating, system consisting of two rotating gears meshed, the lower of which - driven - is constantly located in the oil pan of the crankcase.

Since the ejector is placed in the crankcase, the possibility of damage to its tubes during transportation and operation of the compressor is excluded.

The invention is illustrated by drawings, in which:

FIG. 1 is a longitudinal section of a compressor,

FIG. 2 is a transverse view of the compressor with the front cover removed,

FIG. 3 and FIG. 4 - fragments of the lubrication system,

FIG. 5 and FIG. 6 - options for the location of the metering rings.

The rotary piston compressor (hereinafter referred to as the compressor) consists of an epitrochoid casing 1, closed from the ends of the front 2 and rear 3 side covers, an eccentric shaft 4, on the eccentric part of which a rotor 5 is mounted. A case 6 is attached to the end of the rear side cover 3, closed from the rear end cover of the crankcase 7. The lower part of the crankcase is filled with oil (Fig. 1), there is no breather in the crankcase.

The epitrochoid casing 1, side covers 2, 3 and rotor 5 form working chambers 8 and 9 of variable volume. In Fig.2, the rotor 5 is depicted in two positions: a solid line, when the volume of the chamber 8 is minimal (harmful), the chamber 9 is the maximum (full), and with a dashed line in the intermediate position, when the inlet window 10 begins to open.

The discharge valve 11 is installed in the outlet (injection) well of the housing 1. In the rotor 5, radial 12 and end 13 sealing strips are installed, which are pressed to the working surfaces by expanders and provide sealing of the working chambers 8 and 9.

The lubrication system (Fig. 2, 3 and 4) of the compressor is implemented as an inclined or radial hole 14 made in the working surface of the epitrochoidal housing 1 in the zone of the expansion process and the axial hole 15 connected to it, passing through the epitrochoidal housing 1, rear side flange the cover 3 and the front flange of the crankcase 6, to which the ejector is coaxially connected, consisting of a nozzle 16 and a tube 17 (Figs. 1, 3, 4), while the radial 14 or axial 15 holes in the epitrochoid housing are made coaxially or perpendicularly connected to it and a cylindrical chamber 18 larger than suitable holes 14 and 15 of diameter, closed from the end when the axial arrangement of the chamber by the front side cover 2 (Fig. 3), with a radial arrangement - plug 19 (Fig. 4). A self-acting valve 20 is installed in the cylindrical chamber 18 in the form of a piston (Figs. 3, 4) or a ball, not shown in the figures. An additional buffer volume 21 is attached to the cylindrical chamber 18, and a spring 22 is mounted above the piston (ball); on the working surfaces of the side covers 2 and 3, radial channels 23 are made (FIG. 2), connecting the crankcase cavity 6 with the working chambers 8 and 9 through the annular gap between the eccentric shaft 4 and the rear side cover 3 during the suction process.

Placing the ejector inside the crankcase 6 near the rear side cover 3 improves its working conditions at low temperatures, since during operation of the compressor, the cover 3 heats up, heating and oil located near it, reducing its viscosity. The ejector inside the crankcase is protected from breakage.

At the passage of the eccentric shaft 4 in the hole of the rear side cover 3, ring grooves are made in it or in the eccentric shaft to install mainly of the anti-friction material of the split rings 24 (Fig. 5) or 25 (Fig. 6), which are pressed against the eccentric shaft 4 ( 5) or to the hole of the rear side cover 3 (Fig.6) by the force of their own elasticity and in the place of the cut have a gap of a given value, which doses the amount of gas-oil mixture supplied to the lubrication of the friction parts of the working chambers.

The compressor further comprises, inside the crankcase, rigidly fixed to the eccentric shaft 4, the drive gear 26 and the driven gear 27 (FIG. 1), which is constantly engaged with it, mounted on an axis 28, which is fixedly mounted in the tide of the lower part of the rear side cover 3 so that the lower part of the driven gear is constantly in oil regardless of its level. The specified gear pair is an additional duplicate means of spraying lubricant.

The compressor operates as follows. The eccentric shaft 4 is driven in rotation from the motor shaft (not shown conditionally). From the eccentric shaft, rotation is transmitted to the rotor 5, which performs a planetary motion, rotating with the shaft and turning relative to it. When the rotor rotates, the volume of the working chambers 8 and 9 cyclically changes from minimum to maximum, due to which the working process is carried out. 1 and 2, the solid lines of the rotor 5 are shown in the initial position, when the pumping process has ended in the working chamber 8, the suction process has ended in the working chamber 9, inertial replenishment is ongoing. 2, the rotor 5 is shown in dashed lines in an intermediate position when the expansion process has ended (or is close to the end) in the working chamber 8 and the inlet window 10 begins to open with the radial bar 12, starting the suction process. The gas is sucked in through the inlet window 10. A compression process takes place in the working chamber 9, when the discharge pressure is reached, the discharge valve 1 1 opens and the compressed gas is expelled from it. After the arrival of the rotor 5 to its original position, the working chambers 8 and 9 are interchanged, then the cycle repeats.

The compressor is lubricated with a gas-oil mixture. When the radial sealing strip 12 passes through the radial hole 14 (Fig. 3, 4), the gas having increased pressure is pushed into it, depresses the spring 22 and, as shown in Fig. 3 and 4 moves the piston (ball) 20 to the leftmost position (Fig. 3) or the highest position (Fig. 4), opening the gas flow to the axial hole 15, the ejector nozzle 16 and creating a vacuum in its smaller cross-sectional area, due to which the oil is sucked from the crankcase 6 through the tube 17 and ejected by the nozzle 16 into the crankcase in the form of a finely atomized gas-oil mixture filling the crankcase. Since the working chambers 8 and 9 are connected to the crankcase through the annular gap between the rear side cover 3 and the eccentric shaft 4, as well as the radial channels 23, the gas-oil mixture is sucked into them during the suction process. For dosing the amount of oil-gas mixture supplied to the lubricant in the annular gap installed in the rear side cover 3 (figure 5) or in the eccentric shaft 4 (figure 6) elastic split rings 24 or 25 having a gap of a given (dosing) value. But with the working chambers 8 and 9 during the suction process, an ejector nozzle 16 is also connected, through which the gas-oil mixture can be sucked into the working chambers. In order to block its entry or limit it to the necessary amount for lubricating the working surface of the epitrochoid body 1, a piston (ball) 20 is installed, which, under the influence of rarefaction in the working chambers 8 or 9 and the efforts of the spring 22, sit on their seats, completely or partially blocking the passage for gas-oil suction mixtures. Thus, it is possible to avoid increased oil consumption, carbonization, emission into the atmosphere, environmental improvement. The lack of a breather also contributes to this. Additional buffer volume 21 weakens the effect of pumping strokes and facilitates the movement of the piston (ball) 20.

To ensure reliable, trouble-free operation of the compressor, a duplicate lubrication system is also used. With a high oil viscosity and compressor operation at reduced conditions, when the gas pressure during expansion is insufficient and the ejector cannot work, the oil in the crankcase 6 will be sprayed by the driven gear 27 immersed in it, driven by the drive gear 26.

Claims

Claim

1. A rotary piston compressor comprising an epitrochoid casing with front and rear side covers and a rotor located in its cavity located on an eccentric shaft, the casing, side covers and rotor forming working chambers of variable volume, a lubrication system for compressor working surfaces having a crankcase for the content of lubricant, a device for spraying lubricant in the form of an ejector, the nozzle of which is communicated by a tube with the bottom of the crankcase, a system of channels connecting the ejector to the working chambers, and a device for dispensing according to A lubricant, characterized in that the crankcase for containing the lubricant is attached to the rear side cover, the ejector is installed inside the crankcase, and the channel system is made in the form of a radial or inclined hole made in the housing in the expansion zone and connected to it through a larger diameter axial hole passing through the housing, the flange of the rear side cover and the front flange of the crankcase, and connected to the ejector, radial channels are made on the working surfaces of the side covers for connection through an annular gap, made between the eccentric shaft and the rear side cover, the crankcase cavities with the working chambers during the suction period, while the lubricant dispensing device is made in the form of a spring-loaded valve and a split elastic ring, mainly made of antifriction material having a gap of a predetermined dispensing value at the section of the cut, from which, a spring-loaded valve is installed in front of the ejector in the aforementioned chamber of larger diameter, and a split elastic ring is installed in the annular gap between the eccentric shaft and the rear side cover, wherein the ring is blocked and the annular gap at the point of incision formed gap of a predetermined dosing quantity.

2. The rotary piston compressor according to claim 1, characterized in that a buffer volume is formed above the spring-loaded valve.

3. The rotary piston compressor according to claim 1, characterized in that the split elastic ring is installed in the annular groove made in the hole of the rear side cover.

4. The rotary piston compressor according to claim 1, characterized in that the split elastic ring is installed in an annular groove made in the body of the eccentric shaft.

5. A rotary piston compressor comprising an epitrochoid casing from the front and the rear side covers and the rotor located in its cavity, located on the eccentric shaft, while the housing, side covers and rotor form the working chambers of variable volume, the lubrication system of the compressor working surfaces having a crankcase for containing lubricant, a lubricant spray device in the form of an ejector, a nozzle which is indicated by a tube with the bottom of the crankcase, a system of channels connecting the ejector to the working chambers, and a device for dispensing a lubricant supply, characterized in that an additional oak is installed in the crankcase Lubricant spraying means made in the form of engaged and driven gears, while the drive gear is rigidly fixed to the eccentric shaft, and the axis of the driven gear is fixed at the bottom of the rear side cover so that part of this gear is below the lower level mark grease.