RU2578487C1 - Motor-compressor without conrod - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: motor-compressor without conrod contains a tight enclosure with installed in it compressor, which motor stator is pressed between two casings of the cylinders, located opposite and coaxially relatively to axis of its rotor. The ends of axle projecting from the stator at both sides have the device ensuring movement of pistons along the axle by value of its stroke and torque transfer to the piston jacket. The internal cavity of the cylinders is made out of two coaxial cavities with different diameters, stepped connected between each other such that external cavity of lower diameter is intended for the piston, and of the larger diameter - for its jacket, installed on bearing in the jacket base. On the external cylindrical surface of the jacket the closed zigzag grooves are made, they have hemispheric cross-section, their amplitude of deviation from plane of symmetry is equal to half of the piston stroke, the grooves are linked by the movable joint with the jacket casing through two rollers with hemispheric end faces, coaxially installed on bearings in its lugs. The cavity created during suction stroke between the end face of the jacket and the cylinder shoulder is used as cylinder of the lubricating system of movable parts together with suction valve and pipeline. Two release valves are installed in the internal end part of the jackets. The motor rotor provision by two impellers with mechanical cooling improves the compressor thermal mode.

EFFECT: increased efficiency, reduced vibration and noise, increased capacity and economical efficiency upon keeping of the permanent compression within the entire service life of the compressor.

2 dwg

Description

The invention relates to compressor engineering, in particular the creation of piston blowers used in refrigerators, air conditioners and storage tanks for storing various gases with a pressure of more than one atmosphere.

The well-known compressors KX - 1005 and FG - 0.100 are the main models of domestic household refrigerators using a crank or crank mechanism in a piston drive from an electric motor. The main drawback of these types of drives is the presence of a significant lateral force in the piston-cylinder pair, which leads to the realization of the mechanical efficiency of the drive at a very low level (less than 70%), and therefore the total efficiency of the drive (when taking into account the efficiency of electric motors and used powers, within 74-78%) is reduced to a level of less than 50%. In addition, the inertial imbalance of the drive entails a high level of vibration and noise of the mechanism, especially when starting and stopping, which requires the use of appropriate means of depreciation.

A motor compressor is also known (RF patent No. 2246039C1, 02.10.2005), which is a typical representative of the above types of compressor motors, which is adopted as a prototype of the claimed invention.

The inventive rodless motor compressor (hereinafter BMK) contains a sealed casing, a motor compressor located therein, including a cylinder head with silencers for discharge and suction, an oil separator, a cylinder, a transmission mechanism, a piston, a suction-discharge device made in the form of self-acting suction and discharge valves, the petals of which overlap the surface of the seats formed around the suction and discharge openings of the valve plate.

The objective of the invention was: a significant increase in the mechanical efficiency of the transmission mechanism, a decrease in the level of vibration and noise of the mechanism, as well as an increase in the efficiency and productivity of the BMC.

The solution to this problem is achieved by the fact that in the known motor compressor, the stator of the electric motor is clamped between two cylinder bodies, opposite and coaxially located relative to the axis of its rotor, the ends of which protruding from the stator are provided on both sides with a device for moving the pistons along the axis by their travel transmission of torque, and the inner cavity of the cylinders is formed of two coaxial cavities of different diameters, stepwise articulated to each other so that the outer cavity is smaller the larger diameter is for the piston, and the larger - for its skirt mounted on the bearing at the base of the skirt body, on the outer cylindrical surface of which closed zigzag grooves of a semicircular cross section are formed, the amplitude of deviations of which from the plane of symmetry is equal to half the stroke of the piston, articulated by a movable connection with the body skirts through two rollers with hemispherical contact ends coaxially mounted on bearings in the tides on it, and the cavity formed during the suction stroke between the inner end of the skirt and the ledge of the cylinder serves as the cylinder of the pump of the lubrication system through the pipeline and the inlet valve in the lower part of the cylinder from the crankcase of the hermetic casing and two exhaust valves in the inner end of the skirt through the channels to the zigzag grooves and the piston moving device, while forced cooling the motor-compressor is carried out using two impellers mounted on both sides of the rotor on its axis.

In FIG. 1 shows (section of the outer sealed casing conditionally) BMK section along arrow “A” of the left part of the compressor from the plane of symmetry, the normal axis of the rotor, and the right part along arrow “B” (in 3D format); in FIG. 2 shows a variant of the shape of a zigzag groove.

The BMC consists of the cylinder body 1, the body of the piston skirt 2, the piston 3, the piston skirt 4, on the outer surface of which closed zigzag grooves 5 of a semicircular cross section are formed, the amplitude of deviations of which from the plane of symmetry is equal to half the stroke of the piston 3 (see Fig. 2) articulated by a movable connection through rollers 6 with the skirt body 2, supports 7, couplers 8, stator 9, rotor 10 mounted on a composite axis 11 with two impellers 12 at both ends thereof, grooves 13 of the piston moving device 3, two bearings of the piston skirts 14 two p litsov pistons 15, two cavities of the oil pump 16, two inlet valves with pipelines 17, exhaust valves 18 (two on each piston skirt 4), two cylinder heads 19, two valve plates 20, two oil separators 21 on the suction channels of the heads of the 19 cylinders 1 , two exhaust pipelines of compressed gas 22.

The rodless motor compressor operates as follows. As soon as voltage is applied to the stator windings, the rotor 10 begins to rotate along with the axis 11, transmitting torque to the fingers of the pistons 15, which rotate the skirt 4 and piston 3. The skirts of the pistons 4, interacting with spherical grooves 5 of the semicircular cross section the ends of the rollers 6 mounted in the bearings of the tides of the bodies of the skirts of the pistons 2, which, rotating, transmit the axial component of the reaction at a moment through the skirts 4 to the pistons 3, causing the pistons to move along the grooves 13 of the device movements of the pistons through which the fingers 15 rotating around their axis pass, making a suction or compression stroke (depending on the position of the rollers on the groove branch). The design of the piston drive provides for the pistons to meet each other during the suction stroke and in the opposite direction during the compression stroke, which ensures mutual annihilation of the axial forces acting on the skirt bodies 2 when the pistons 3 move along the axis of the cylinders 1. Dynamic balancing of the rotor assembly with the impellers, with fingers and pistons minimizes radial vibrations. As a result, the vibrations on both of the mentioned axes do not exceed 0.05 mm in all modes (start, work, stop). Placing the rear part of the skirts of the pistons 4 in the bearings of the bodies of the skirts 2 provides reliable centering of the rotor 10 relative to the stator 9, which allows for the non-contact movement of the piston 3 relative to the inner surface of the cylinder body 1 with a specified minimum clearance.

All BMC moving parts are lubricated by using the cavity 16 formed during the suction process as a cylinder of the piston oil pump, which receives oil from the casing crankcase through the pipe and the intake valve 17 during suction, which is forced out during compression through two exhaust valves 18 in the inner ends of the skirts 4 through the provided channels to the movable drive units. The absence of hydraulic shocks in the pump is ensured by appropriate balancing of the oil flow through the inlet and outlet valves and the guaranteed presence of a gas cushion of a certain volume in the upper part of the cavity of the skirt body. An oil film in the gap between the piston 3 and the cylinder body 1 with a stable differential pressure between the pump cavity and the cylinder injection cavity, preventing oil from entering the cylinder injection cavity, which is ensured by the specified clearance between the piston and the cylinder, as well as the predetermined oil flow rate through the intake and exhaust valves , creates the conditions for maintaining constant compression (due to the absence of wear of the mating surfaces) throughout the entire life of the BMC. Forced cooling using two centrifugal impellers 12 during BMK operation, by creating a circulation flow on both sides of the BMK stator, maintains intensive heat removal from the compressor and heat transfer to the inner surface of the sealed casing, which improves the thermal operation of the BMK.

The estimates show that the BMC of this design can have a mechanical efficiency of more than 94%, and, with the same electric powers of the electric motors used, with a traditional drive circuit, it gives a 1.5-fold increase in productivity, a decrease in vibration to a level of less than 0.05 mm in all axes and virtually silent operation in all modes.

Claims (1)

A rod-free motor-compressor containing a sealed casing, a motor-compressor located in it, including a cylinder head with silencers for discharge and suction, an oil separator, a cylinder, a transmission mechanism, a piston, a suction-discharge device made in the form of self-acting suction and discharge valves, the petals of which overlap the surface of the seats formed around the suction and discharge openings of the valve plate, characterized in that the stator of the electric motor is sandwiched between two bodies of qi of cylinders opposite and coaxial with respect to the axis of its rotor, the ends of which protruding from the stator on both sides are equipped with a device for moving the pistons along the axis by their travel and torque transmission, the inner cylinder cavity being formed of two coaxial cavities of different diameters, articulated between each other so that the outer cavity of a smaller diameter is intended for the piston, and the larger for its skirt mounted on a bearing at the base of the skirt body, on the outer cylinder on the surface of which closed zigzag grooves of a semicircular cross section are formed, the amplitude of deviations of which from the plane of symmetry is equal to half the piston stroke, articulated by a movable connection to the skirt body through two rollers with hemispherical contact ends coaxially mounted on bearings in the tides on it, and the cavity formed during the suction stroke between the inner end of the skirt and the ledge of the cylinder serves as the cylinder of the pump of the lubrication system through the pipeline and the intake valve to the bottom s portion of the cylinder from the crankcase sealed housing and two exhaust valves at the inner end of the skirt through the passages to the grooves and zigzag movement of the piston device, wherein the forced cooling of the motor-compressor by means of two impellers fixed on either side of the rotor on its axis.

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