KR100813585B1 - Oil pump for a reciprocating hermetic compressor - Google Patents

Abstract

An oil pump for a hermetic reciprocating compressor comprising a pump body (11) driven by a compressor such that the free end (12) is submerged in oil, the opposite end (13) is coupled to the compressor, and is axially reciprocated. The pump body 11 has a valve seat 15 at its free end 12 and also houses a sealing means 20, which sealing means 20 is seated on the valve seat 15. A closed reciprocating displacement between the closed position and the open position away from the valve seat 15, the open position and the closed position resulting in displacement of the pump body 11 approaching and away from the sealing means 20 therein. Compressor oil pump.

Oil pump, pump body, sealing means, valve seat, lubricating oil induction tube, radial projection, spring member

Description

OIL PUMP FOR A RECIPROCATING HERMETIC COMPRESSOR}

The present invention relates to oil pumps for hermetic reciprocating compressors of the type used in small refrigeration appliances such as refrigerators, freezers, chillers and the like, and particularly to oil pumps applied to compressors of the type driven by conventional reciprocating compressors or linear motors. It is about.

In hermetic compressors for industrial and domestic refrigeration appliances, an important factor in the correct operation of the appliance is the proper lubrication of the components moving relative to one another. The difficulty in obtaining this lubrication involves the fact that the oil must flow upward to lubricate the relatively moving parts. Among the known solutions for obtaining such lubrication are the use of the principles of centrifugal force and mechanical drag.

In one of these solutions, which is used in both linear compressors and reciprocating compressors, in order to supply oil to the piston / cylinder assembly, it is necessary to create a gas flow on the suction side of the compressor, which is an oil sump. Generate a small pressure differential over the oil, suck the oil through the capillary and mix it with the gas sucked by the compressor, and put the mixture inside the cylinder by the suction valve, Lubricate the contacts. Depending on the low gas flow drawn by the compressor in some situations, this structure is not always efficient.

In another known structure (WO97 / 01033), the compression and suction forces of the piston are used to transfer lubricant from an oil sump to an upper reservoir formed around a cylinder through a capillary, which is driven by a number of orifices formed in the wall of the cylinder. It is connected to the inside of the cylinder, and acts to introduce oil into the gap between the piston and the cylinder when the piston performs the suction movement and to discharge the oil when the piston performs the opposite movement. The oil is discharged into a plurality of channels formed in the valve plate of the compressor, further increasing the suction flow and allowing the oil to re-enter the cylinder.

Another known solution (WO97 / 01032) uses a resonant mass that reciprocates inside a cavity formed outside the cylinder, which retracts oil from the oil sump while moving in one direction, and The oil passes through the tube and also through a one-way valve that only allows oil to enter the cavity. The cavity is connected to the inside of the cylinder by a plurality of orifices formed in the wall of the cylinder. The oil in the cavity is released as the resonant mass moves in the other direction and passes through a one-way valve that only allows oil to leave the cavity. This solution is functional but difficult to fabricate, and its structure has a large number of components.

Accordingly, an object of the present invention is a low cost and easy to manufacture hermetic reciprocating which makes it possible to perform proper lubrication of relative moving compressor components, without the difficulties indicated by known prior art solutions and without the low efficiency of such solutions. An oil pump for a compressor is provided.

The above and other objects are oil pumps for hermetic reciprocating compressors comprising a shell in which an oil sump is defined therein and containing a cylinder in which a piston driven by an actuator reciprocates therein. The oil pump comprises a tubular pump body having a free end submerged in oil and an opposite end connected to a lubricating oil induction tube guiding oil to the relative moving compressor parts, the pump body having its free end. A valve seat is provided at the end and also receives a sealing means, which is displaced between a closed position seated on the valve seat and an open position away from the valve seat. The open position and the closed position approach the pump body with respect to the sealing means therein due to the reciprocating motion. When performing a high-away displacement is achieved by means of a hermetic reciprocating a compressor oil pump is obtained.
Hereinafter, the present invention will be described with reference to the accompanying drawings.

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1 is a schematic longitudinal cross-sectional view of a portion of a hermetic reciprocating compressor with a linear motor having an oil pump constructed in accordance with one embodiment of the present invention, with the axis of the piston disposed in a vertical direction.

FIG. 2 is a schematic longitudinal cross-sectional view of a portion of a hermetic reciprocating compressor with a linear motor, constructed in accordance with the embodiment of the invention shown in FIG. 1, with the axis of the piston disposed horizontally;

3 (a), 3 (b) and 3 (c) are diagrams schematically showing the operation of the oil pump of the present invention shown in FIG.

4 (a) and 4 (b) are schematic representations of two oil pumps of the present invention displaced from each other by 90 ° and attached to the eccentricity of the crankshaft of the hermetic reciprocating compressor.

5 (a), 5 (b) and 5 (c) are diagrams schematically showing the operation of another structural form for the oil pump of the present invention in a horizontal position.

The invention is described in the context of a hermetic reciprocating compressor (eg of a type applied to a cooling system) with a shell 1 which houses a cylinder 2 in which the piston 3 reciprocates. do. An oil sump 4 is defined inside the shell 1, from which lubricant of the movable part of the compressor parts is pumped by the oil pump 10.

1 and 2, the hermetic reciprocating compressor is driven by a linear motor and the piston 3 is driven by an actuator 5.

In another optional structure (shown in FIGS. 4 (a) and 4 (b)) described later, the hermetic reciprocating compressor is of a type driven by the crankshaft 6 which moves the piston 3.

In the hermetic reciprocating compressor provided with the linear motor, the reciprocating motion of the piston 3 is performed by the actuator 5 supporting the magnetic component driven by the linear motor. The piston 3 is connected to the resonant spring 7 by means of a connecting rod, which together with the resonant spring and the magnetic component form a resonant assembly of the compressor. The non-resonant assembly of the compressor includes a cylinder 2, a suction and discharge system, and a linear motor.

According to the invention, the oil pump 10 comprises a tubular pump body 11, the free end 12 of which is submerged in oil and the opposite end 13 is an oil sump 4. It is connected to a lubricating oil induction tube 14 for guiding oil from. The oil is pumped by the pump body 11 between the relatively moving compressor parts, in particular between the inner wall of the cylinder 2 and the piston 3.

The pump body 11 may vibrate at an oscillation amplitude which is a function of the ratio of the mass of the piston (and all its parts) to the mass of the compressor as the compressor reacts with the resonance force associated with the vibrating mass therein. When coupled to the compressor to be driven in an axial reciprocating motion caused by the operation of the compressor.

The pump main body 11 has a valve seat 15 at its free end 12 and houses a sealing means 20. This sealing means is displaced between the closed position seated on the valve seat 15 and the open position away from the valve seat 15. This open position and closed position are obtained when the pump body 11 makes a displacement near and away from the sealing means 20 therein due to the reciprocating motion.

In the illustrated embodiment, the valve seat 15 is formed in the tapered portion of the pump body 11 adjacent to the free end 12 of the pump body 11.

According to the invention, the pump body 11 of the oil pump 10 is coupled to the compressor by a lubricating oil induction tube 14.

The operation of the oil pump of the present invention by the compressor occurs as a result of the vibrational movement of the compressor, for example resulting from the reaction force of the resonant assembly. Such vibratory motion is possible because the compressor is supported by a suspension spring.

In the structure of a hermetic compressor with a linear motor, the lubricating oil induction tube 14 is attached to the compressor, for example, by means of which one fixed end 14a is fitted in a channel 2a provided in the body of the cylinder 2. 1 and 2, which typically provides a substantially vertical development (FIG. 1). Nevertheless, the channel 2a may have a substantially horizontal extension, as in a configuration with a linear motor having a horizontal axis (FIG. 2).

In the solution of the invention, the pumping mechanism depends on the inertial effects of the oil contained in the lubricating oil induction tube 14. This oil column generates a flow when the motion is downward (see FIG. 3 (b)), and in upward motion the sealing means 20 prevents oil from flowing out of the lubricating oil induction tube 14 (FIG. 3 (c). ) Reference).

According to an optional structure of the invention shown in FIGS. 1 and 2 with respect to a compressor with a linear motor, the operation and movement of the oil pump is, for example, an assembly of a spring 8 supporting the compressor (FIG. 1). And reciprocating motion of the compressor in the shell 1, which vibrates in the same direction as these springs 8 in accordance with the vibrating motion of FIG. 2). This vibration of the compressor results from the mounting of the compressor on the shell by the suspension springs. If the compressor is not mounted by a spring in the shell, this vibration will not be present.

In the structure in which the reciprocating compressor has the crankshaft 6 (FIGS. 4A and 4B), the motion and operation of the oil pump of the present invention are, for example, the crankshaft 6 (FIG. 4). (a) and 4 (b)). In this case, the lubricating oil induction tube 14 is eccentrically attached to the eccentric of the crankshaft 6 at right angles to its axial axis, whereby as a result of the rotation of the crankshaft 6 during operation of the compressor, An axial displacement of the oil pump of the invention away from or approaching the oil sump 4 takes place.

In the structure shown, the lubricating oil induction tube 14 has a tubular extension 14c, which is connected by the receiving end 14b to the adjacent end of the pump body 11 (the end of the pump body being immersed in lubricating oil). On the opposite side), and is fixed to the compressor at its fixed end 14a.

According to the structural form of this invention shown to FIG. 3 (a)-FIG. 3 (c), the sealing means 20 is a floating member which shows a substantially spherical outline, for example, and pumps Between the valve seat 15 and the position in the pump body 11 away from the valve seat 15 as a result of the movement of the compressor element, which is provided inside the body 11 and causes displacement of the sealing means 20. Is rich between.

In the optional structure shown, the distal movement of the sealing means 20 relative to the valve seat 15 is limited by the stop means formed in the pump body 11 away from the valve seat 15.

In the structure shown (FIGS. 3A-3C), the stop means is formed inside the pump body 11, for example by radial projections 16, and the valve seat 15 It is located at a predetermined distance from the. This protrusion at least occupies some length transverse to the longitudinal axis of the pump body 11, sufficient to prevent free and unrestricted movement of the sealing means 20 inside the pump body 11. .

The predetermined distance between the valve seat 15 inside the pump body 11 and the stop means is defined to optimize oil pumping in the compressor.

In another embodiment of the present invention shown in Figs. 5 (a) to 5 (c), the stop means has one end portion mounted to the opposite end portion 13 of the pump body 11 and the other end portion sealed. It is in the form of a spring member 36 which is coupled to the means 20. This spring member 36 defines the open position of the sealing means 20 in the first operating position and defines the closed position of the sealing means 20 in the second operating position.

According to the embodiment shown in FIGS. 5A-5C, the sealing means 20 presses the spring member 36 to a maximum value that determines the opening limit of the sealing means 20 when in the open position. do.

In an optional configuration, the spring member 36 further has a non-operational rest position (Fig. 5 (b)) intermediate between the first and second operating positions, in which the sealing means 20 stays away from the valve seat 15 when attached to the other end of the spring member 36 and is prevented from seating on the valve seat. This non-operational position is obtained when the compressor is not operating.

Although an embodiment is provided with stop means in the form of a spring member 36 provided in the pump body 11, it is possible to describe any interior portion of the pump body 11, such as, for example, the radial projection 16. It will be appreciated that installation may be done. In addition, when the stop means is formed by the floating spring member 36, a sealing means 20 may be provided inside the pump body 11, and the open position of the sealing means 20 is a result of the operation of the compressor. It will be appreciated that the furnace sealing means 20 is obtained by applying pressure to the spring member 36.

5 (a) to 5 (c) show the structure in which the oil pump of the present invention is in the horizontal direction, it will be understood that this embodiment can be applied to the structure in which the oil pump 10 is in the vertical direction.

Claims (14)

Closed reciprocating compression including a shell 1 having an oil sump 4 defined therein and containing a cylinder 2 in which the piston 3 reciprocates therein. In the oil pump for the machine, The oil pump has a tubular pump body (11) having a free end (12) submerged in oil and an opposite end (13) connected to a lubricating oil induction tube (14) for guiding oil to relative moving compressor parts. A pump seat (11) coupled to the compressor such that the pump body (11) is operated in axial reciprocating motion, the pump body (11) having a valve seat (15) at its free end (12); And, further, a sealing means 20 is received, the sealing means 20 being displaced between a closed position seated on the valve seat 15 and an open position away from the valve seat, The open position and the closed position are obtained when the pump body 11 makes a displacement near and away from the sealing means 20 therein due to the reciprocating motion. Program. 2. The oil pump for a hermetic reciprocating compressor according to claim 1, wherein the coupling of the pump main body (11) to the compressor is performed through the lubricating oil induction tube (14). 3. The oil pump for a hermetic reciprocating compressor according to claim 2, wherein the lubricating oil induction tube (14) is attached to the cylinder (2). 4. A reciprocating compressor of the type according to claim 3, wherein the compressor has a crankshaft (6) for driving the piston (3), wherein the lubricating oil induction tube (14) is perpendicular to its axial axis. An oil pump for a hermetic reciprocating compressor, which is attached eccentrically to (6). 4. The oil pump for a hermetic reciprocating compressor according to claim 3, wherein the compressor is driven by a linear motor, and movement of the pump main body (11) is obtained by reciprocating motion of the compressor. 2. The oil pump according to claim 1, wherein the oil pump is provided away from the valve seat 15 inside the pump body 11, and the pump body 11 approaches the sealing means 20 therein. And a stop means (16, 36) for limiting the displacement away from the pump. 7. A hermetic reciprocating compressor as claimed in claim 6, characterized in that the stop means is formed in the pump body (11) with radial projections (16) arranged at a predetermined distance from the valve seat (15). Oil pump. The said stop means is formed with the spring member 36 in which one end part is attached to the said pump main body 11, and the other end part is couple | bonded with the said sealing means 20, The spring member 36 defines the open position of the sealing means 20 in the first operating position and the closed position of the sealing means 20 in the second operating position. Pump. 9. The oil pump of claim 8, wherein the sealing means (20) pressurizes the spring member (36) in the first operating position. 10. The oil pump of claim 9, wherein the spring member (36) has a non-operating position intermediate between the first and second operating positions. 10. The oil pump for a hermetic reciprocating compressor according to claim 9, wherein one end portion of the spring member (36) is attached to the opposite end portion of the pump body (11). 10. The oil pump for a hermetic reciprocating compressor according to claim 9, wherein the other end portion of the spring member (36) is mounted to the sealing means (20). The oil pump for a hermetic reciprocating compressor according to claim 1, wherein said sealing means (20) is a floating member provided inside said pump main body (11). 14. The oil pump for a hermetic reciprocating compressor according to claim 13, wherein said sealing means (20) is a sphere.

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