JPH1082393A - Closed type compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent over lubrication at the time of high speed rotation of a compressor furnished with a displacement type pump. SOLUTION: An oil pump is constituted of a displacement type pump stored in a casing 24, an end plate 30 having a discharge port 29 provided on an end surface of the casing 24, a valve 32 to elastically cover the discharge port 29 and a cover 34 to cover a back surface of this valve 32, and the back surface of the valve 32 is communicated to a pump suction side 35, when pump pressure becomes higher than set pressure at the time of high speed driving, the valve 32 is opened, pump capacity is lowered and over lubrication to a compression mechanism is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic compressor used as a refrigerant compressor or air compressor for refrigeration and air conditioning.

[0002]

2. Description of the Related Art Conventionally, in this type of compressor, as shown in FIG. 3, a stator 104 of a motor 103 for driving a compression mechanism 102 is fixed inside a closed container 101, and a rotor 105 of the motor 103 is fixed. A crankshaft 106 for driving the compression mechanism 102 is connected to the crankshaft 106, and the rotation axis of the crankshaft 106 is disposed substantially horizontally. In addition, the closed container 101
Is a lubricating oil reservoir 107.

A compression mechanism 102 is a fixed spiral blade member 110 in which a fixed spiral blade 109 is formed integrally with a fixed frame 108.
And a swirling spiral blade member 113 in which a swirling spiral blade 111 meshing with the fixed swirl blade 109 to form a plurality of compression working spaces 114 is formed on a swiveling end plate 112, and prevents the swirling spiral blade member 113 from rotating. The rotation end plate 112
Drive shaft 1 provided on the opposite side of the swirling blade 111
16 is a main shaft 117 formed at one end of the crankshaft 106.
The crankshaft 106 is fitted into an eccentric bearing 118 provided inside the main bearing 11.
9 and a sub bearing 121 that supports the shaft of the crankshaft 106 on the opposite side of the main shaft. The auxiliary bearing 121 is provided with a casing 123 for providing an oil supply mechanism 122 at an end of the crankshaft 106. The casing 123 has a trochoid pump (a positive displacement pump) including an outer rotor 124 and an inner rotor 125. Is mounted and the inner rotor 1
25 is a pump shaft 1 formed at the end of the crankshaft 106.
26. Further, an oil suction pipe 127 is connected to the casing 123, and the lower end of the oil suction pipe 127 is immersed in the lubricating oil reservoir 107.

On the other hand, the crankshaft 106 and the pump shaft 12
An oil feed passage 128 is formed in 6, one of which is connected to the trochoid pump, and the other is connected to each sliding portion of the compression mechanism 102.

[0005] The refrigerant sucked from the suction pipe 129 of the compressor is compressed in the compression working space 114 in the compression mechanism 102, passes through the discharge hole 130, passes through the discharge pipe 131 provided in the sealed container 101, and flows out of the compressor. Is discharged to
9-60092).

[0006]

However, in the above-mentioned conventional construction, the amount of lubrication of the positive displacement pump is determined by the number of revolutions of the crankshaft.
In addition to causing an increase in pump input, lubricating oil that passed through the sliding part of the compression mechanism scattered into the closed container, was taken out of the compressor together with refrigerant, and reduced the amount of lubricating oil in the closed container and reduced There was a problem of causing a decline in ability.

SUMMARY OF THE INVENTION The present invention solves such a conventional problem, and prevents supercharging of lubricating oil during high rotation, suppresses lubricating oil from scattering into a closed container, and achieves low input and high reliability. An object of the present invention is to provide a compressor.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an electric motor having a variable rotation speed, a compression mechanism driven by the electric motor, and a lubricating oil at the bottom inside a closed container. A casing, a positive displacement pump housed in the casing, and a discharge port provided on an end face of the casing are provided at an end of the crankshaft that transmits the rotational force of the electric motor to the compression mechanism, at an end opposite to the compression mechanism. An oil pump comprises an end plate, a valve that elastically covers the discharge port, and a cover that covers the back surface of the valve, and the back surface of the valve communicates with the pump suction side. With the above configuration, during high-speed operation, when the pump pressure increases, the valve opens, reducing the pump capacity and preventing supercharging of the compression mechanism.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An electric motor having a variable number of revolutions, a compression mechanism driven by this electric motor, and a lubricating oil are provided at the bottom inside a closed container, and the torque of the electric motor is transmitted to the compression mechanism. At the end opposite to the compression mechanism of the crankshaft, a casing, a positive displacement pump housed in the casing, an end plate having a discharge port provided on the end face of the casing, and elastically cover the discharge port. An oil pump is composed of a valve and a cover that covers the back of the valve, and the back of the valve communicates with the pump suction side. With the above configuration, the valve is opened when the lubricating oil discharged from the positive displacement pump becomes higher than the set pressure during high-speed operation, and the capacity of the positive displacement pump is reduced. In addition, the back side of the valve constitutes a room covered with a cover, and the lubricating oil that has exceeded the set pressure is discharged into the cover, which reduces pump input, suppresses lubricating oil from scattering into the sealed container, and The lubricating oil surface can be stabilized.

According to a second aspect of the present invention, an oil pump suction port is provided in the casing, and the discharge port is connected to an oil supply path provided in the crankshaft. The same effect as the first aspect is obtained.

Further, in the invention of claim 3, the crankshaft is arranged horizontally, and the effect is remarkable in the case of a horizontal type.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

One embodiment of the present invention is shown in FIGS. In the figure, a stator 4 of a motor 3 having a variable number of rotations for driving a compression mechanism 2 is fixed inside a closed container 1, and a crankshaft 6 for driving the compression mechanism 2 is attached to a rotor 5 of the motor 3.
And the rotation axis of the crankshaft 6 is arranged substantially horizontally. The lower part of the sealed container 1 is a lubricating oil reservoir 7.

The compression mechanism 2 includes a stationary frame 8 and fixed spiral blades 9.
And a swirling spiral blade member 13 in which a swirling spiral blade 11 that meshes with the fixed spiral blade 9 to form a plurality of compression work spaces 14 is formed on a swiveling end plate 12. A turning drive shaft 16 provided on the opposite side of the swirling blade 11 of the turning head plate 12 has a rotation drive shaft 16 provided with a rotation restricting member 15 for preventing the rotation of the turning spiral blade member 13 from rotating and performing only the turning. The crankshaft 6 is fitted into an eccentric bearing 18 provided inside a main shaft 17 formed at one end. The crankshaft 6 has a main bearing member 20 having a main bearing 19 for supporting the main shaft 17 and a crankshaft opposite to the main shaft. 6 is supported by a partition member 21 having a sub bearing 22 for supporting the shaft portion. The partition member 21 is provided with a casing 2 for providing an oil supply mechanism 23 at the end of the crankshaft 6.
The casing 24 is provided with a trochoid pump (a positive displacement pump) including an outer rotor 25 and an inner rotor 26 and an oil pump suction port 27. The inner rotor 26 is connected to an end of the crankshaft 6. Is fitted on the pump shaft 28 formed at the bottom. The trochoid pump mounted in the casing 24 includes an end plate 30 having a discharge port 29 provided on an end face of the casing 24, a valve 32 for elastically covering the discharge port 29 with a spring 31, The valve rear chamber 33 communicates with a pump suction side 35 through a communication hole 36. Further, an oil suction pipe 37 is connected to the pump suction side 35, and the lower end of the oil suction pipe 37 is immersed in the lubricating oil reservoir 7, and the lubricating oil sucked by the trochoid pump passes through the oil feed passage 38, Each part of the compression mechanism 2 is supplied with oil.

The refrigerant sucked from the suction pipe 39 of the compressor is:
Compressed in the compression working space 14 in the compression mechanism 2,
After passing through 0, it is discharged outside the compressor through a discharge pipe 41 provided in the closed container 1.

With the above configuration, as the rotational speed increases, the capacity of the trochoid pump also increases proportionally, and the pressure of the lubricating oil supplied to the oil supply passage 38 increases. When the pressure of the lubricating oil becomes equal to or higher than the set pressure, the discharge port 2 communicated with the oil supply passage 38
The valve 32 that elastically covers the cylinder 9 with a spring 31 is opened to reduce the capacity of the trochoid pump, prevent supercharging of the compression mechanism 2 and reduce the pump input. Is returned from the valve 32 to the valve rear chamber 33 isolated from the internal space of the closed container 1, and the communication hole 36
, The oil is again supplied from the pump suction side 35 to the oil supply passage 38 by the trochoid pump, whereby the lubricating oil can be prevented from scattering into the closed container 1 and the lubricating oil level can be stabilized. Further, the oil pump suction port 27 is provided in the casing, and the discharge port 29 is connected to the oil supply passage 38 provided in the crankshaft 6, so that the structure can be simplified and the size can be reduced.

Further, although the pump has been described as a trochoid pump, other types of positive displacement pumps such as an oscillating pump are also possible. The valve has been described as being elastically fixed by a spring. However, a similar effect can be obtained with a reed valve having the valve itself elastic.

[0018]

As is clear from the above embodiment, according to the first aspect of the present invention, the pressure of the lubricating oil supplied to the oil supply passage increases when the rotation speed increases, and when the pressure exceeds the set pressure, the cover oil increases. A valve that elastically covers the discharge port, which communicates with the oil feed passage provided inside, with a spring is opened to reduce the capacity of the trochoid pump, prevent supercharging to the compression mechanism, and reduce pump input. At the same time, the lubricating oil that has exceeded the set pressure is returned from the valve to the valve back chamber separated from the internal space of the sealed container by the cover, passes through the communication hole, and is again supplied to the oil supply path from the pump suction side by the trochoid pump. This can prevent the lubricating oil from scattering into the closed container and stabilize the lubricating oil surface, thereby improving reliability.

Further, by providing the oil pump suction port in the casing and connecting the discharge port to the oil supply path provided in the crankshaft as in the second aspect of the invention, the structure is simple and the above-described effects can be obtained. can get.

Further, in the case of the horizontal type in which the crankshaft is arranged horizontally as in the third aspect of the present invention, the above-mentioned effects become remarkable.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a scroll compressor showing one embodiment of the present invention.

FIG. 2 is a sectional view of a main part of FIG. 1 showing a positive displacement pump of the present invention.

FIG. 3 is a cross-sectional view of a conventional scroll compressor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Closed container 2 Compression mechanism 3 Electric motor 6 Crankshaft 23 Oil supply mechanism 24 Casing 27 Oil pump suction port 29 Discharge port 30 End plate 32 Valve 34 Cover 35 Pump suction side 38 Oil feed path

Claims (3)

[Claims] An electric motor having a variable number of revolutions, a compression mechanism driven by the electric motor, and a lubricating oil disposed at a bottom of the closed container, and a crankshaft for transmitting a rotational force of the electric motor to the compression mechanism. At the end opposite to the compression mechanism, a casing, a positive displacement pump housed in the casing, an end plate having a discharge port provided on the end face of the casing, and a valve that elastically covers the discharge port. A hermetic compressor in which an oil pump is constituted by a cover that covers the back of the valve, and the back of the valve communicates with the pump suction side. 2. The hermetic compressor according to claim 1, wherein an oil pump suction port is provided in the casing, and the discharge port is connected to an oil feed passage provided on the crankshaft. 3. The hermetic compressor according to claim 1, wherein said crankshaft is arranged horizontally.