JP2004293316A - Oil supply mechanism for hermetic compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reliable oil supply device for a hermetic compressor capable of miniaturization by reducing length of a rotating shaft due to ability to supply oil to each sliding part and prevent each sliding part from being oil-less even if speed of a motor is changed to low speed by using an inverter. <P>SOLUTION: In the oil supply device for the hermetic compressor having an electric element 4, a compression element 3 and an oil supply hole 17 supplying oil in an oil reservoir 7 to a sliding part of the compression element 3 in a hermetic vessel having the oil reservoir 7 at a bottom part thereof and having a rotating shaft 5 transmitting torque of the electric element 4 to the compression element 3 stored therein, and having an oil pick up 21 dipped in oil in the oil reservoir 7 and locked in the oil supply hole 17 provided at a lower end of the rotating shaft 5, the center of the oil supply hole 17 in the oil pick up 21 side is shifted from the center of the rotating shaft and the oil supply hole 17 is tilted in the shifting direction by 2.3 ° or more in relation to the rotating shaft 5. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a lubrication mechanism for a hermetic compressor, and more specifically, to reduce the number of rotations of a motor by using an inverter to save energy even when the number of rotations of the motor is reduced. The present invention relates to an oil supply mechanism of a hermetic compressor capable of supplying oil.
[0002]
[Prior art]
Conventionally, an oil supply device of a general hermetic compressor has an oil pump member formed by a tubular oil pickup formed by press-drawing an iron plate or an iron pipe and a paddle formed by processing a thin plate. Is press-fitted into the lower end of the rotating shaft and attached, so that oil is supplied to each sliding portion using centrifugal force generated by rotation of the rotating shaft (for example, see Patent Document 1).
However, since the conventional oil supply device is formed by pressing an iron plate or an iron pipe, there has been a problem that the processing accuracy of the oil pump is hardly obtained and the oil pump characteristics are impaired.
Therefore, the oil pump may be formed integrally with resin (see Patent Document 2), may be formed integrally with metal injection molding (see Patent Document 3), or an oil pickup formed of plastic may be used as a gas vent that also serves as a mounting pin. It has been proposed to lock the rotary shaft with a component (see Patent Document 4).
[0003]
FIG. 3 is an explanatory diagram showing a cross-sectional structure of a rotary shaft and an oil supply hole of an oil supply device of a conventional hermetic compressor.
An oil supply hole 17 for supplying oil to each sliding portion such as a compression element and a bearing (not shown) is provided in the center of the rotating shaft 5. An oil pickup 21 is attached to the lower end of the rotary shaft 5 and communicates with the oil supply hole 17, and is configured by immersing the lower end in oil in an oil reservoir (not shown). The oil pickup 21 is formed integrally with a paddle 24 for improving the oil supply capacity.
In the oil supply device of the hermetic compressor configured as described above, when an electric element (not shown) is energized, the rotary shaft 5 is rotated, and the piston of the compression element (not shown) is moved in the cylinder by the crank pin 12 of the rotary shaft 5. It slides back and forth to compress the refrigerant. Oil in an oil reservoir (not shown) is supplied to each sliding portion of a bearing or a compression element (not shown) through an oil supply hole 17 from an oil pickup 21 attached to a lower end of the rotary shaft 5 by centrifugal force generated by rotation of the rotary shaft 5. You. 17A indicates an oil supply hole on the oil pickup 21 side, and 17B indicates an oil supply hole on the oil outlet 22 side. 23 is a gas vent hole.
[0004]
However, the center of the oil supply hole 17 </ b> A on the oil pickup 21 side is provided so as to coincide with the center of the rotary shaft 5, and the oil supply hole 17 is provided so as to be parallel to the rotary shaft 5 with both center lines coincident with each other. Therefore, when the centrifugal force generated by the rotation of the rotating shaft 5 is small, and particularly when the motor rotation speed is reduced by changing the rotation speed of the motor using an inverter, oil cannot be supplied to each sliding portion and the oil becomes oilless. In some cases, there are problems such as a decrease in reliability and a reduction in size.
[0005]
[Patent Document 1]
Japanese Utility Model Publication No. 1-30631 [Patent Document 2]
JP-B-63-38553 [Patent Document 3]
JP-A-2-86971 [Patent Document 4]
JP-A-6-17755
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problem and increase the centrifugal force generated by the rotation of the rotating shaft to reduce the amount of oil even when the rotation speed of the motor is reduced by changing the rotation speed of the motor using an inverter. To provide a highly reliable oil supply device for hermetic compressors, which can be supplied to moving parts and can prevent each sliding part from being oilless, so that the length of the rotating shaft can be reduced and the size can be reduced. It is.
[0007]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided an oil supply device for a hermetic compressor, comprising: an electric element and a compression element in an airtight container having an oil reservoir at a bottom; It has an oil supply hole to be supplied to the sliding part, and a rotary shaft for transmitting the rotational force of the electric element to the compression element is housed therein. In an oil supply device of a hermetic compressor provided with an oil pickup to be locked,
The center of the oil supply hole on the oil pickup side is shifted from the center of the rotation shaft, and the oil supply hole is inclined at an angle of at least 2.3 ° with respect to the rotation shaft in a direction substantially shifted. It is characterized by the following.
[0008]
By providing the center of the oil supply hole on the oil pickup side to be shifted from the center of the rotation axis, and providing the oil supply hole at an angle of 2.3 ° or more with respect to the rotation axis in a substantially shifted direction, Even if the rotation speed of the motor is reduced by using the inverter to reduce the rotation speed of the motor, the centrifugal force against the oil generated by the rotation of the rotating shaft increases, and the oil can be supplied to each sliding portion in a stable manner. Since the moving portion can be prevented from being oilless, the length of the rotating shaft can be reduced to reduce the size, and the reliability is improved.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS.
FIG. 1 is an explanatory view illustrating an embodiment of a lubricating device for a hermetic compressor according to the present invention. FIG. 2 is a cross-sectional view of a rotary shaft and a lubricating hole of the lubricating device for a hermetic compressor shown in FIG. It is explanatory drawing which shows a structure.
Reference numeral 1 denotes a closed container, in which a motor case 2, a compression element 3 disposed on the upper side of the motor case, an electric element 4 also disposed on the lower side, and a rotational force of the electric element are compressed. The rotating shaft 5 for transmitting to the element 3 is housed. The compression element 3 and the electric element 4 are suspended and supported by the elastic support device 6 on the inner wall of the closed casing 1 via the motor case 2. An oil reservoir 7 for storing oil is provided at the bottom in the closed container 1.
The electric element 4 includes a stator 9 having a winding 8 therein, and a rotor 10 disposed inside the stator and having a rotating shaft 5 inserted in the center.
The compression element 3 includes a cylinder 11, a piston 13 fitted in a crank pin 12 of the rotating shaft 5 and reciprocally slidable in the cylinder, and a cylinder head 15 mounted on an end surface of the cylinder 11 via a valve seat 14. It is composed of A bearing 16 that supports the rotating shaft 5 is integrally formed with the motor case 2.
[0010]
An oil pickup 21 is attached to the lower end of the rotating shaft 5 and communicates with the oil supply hole 17, and has a lower end immersed in the oil of the oil reservoir 7. 17A indicates an oil supply hole on the oil pickup 21 side, and 17B indicates an oil supply hole on the oil outlet 22 side. 23 is a gas vent hole. 21A is a hole for inserting the oil pickup 21 and attaching it to the lower end of the rotating shaft 5.
The oil pickup 21 is formed integrally with a paddle 24 for improving the oil supply capacity.
[0011]
The center 30 of the oil supply hole 17A on the oil pickup 21 side is provided in the rotary shaft 5 at a position shifted by 0.91 mm from the center 50 of the rotary shaft 5, and the rotary shaft 5 is moved 2.3 degrees to the rotary shaft 5 in a substantially shifted direction. The oil supply hole 17 is provided at an angle of not less than 0 °, preferably 2.3 ° to 3.4 °, more preferably 2.85 ° to 3.35 °. In this example, the oil supply hole 17 is provided at an angle of 2.85 °.
[0012]
In the oil supply device of the hermetic compressor configured as described above, when the electric element 4 is energized, the rotating shaft 5 is rotated by the rotor 10, and the rotational force of the electric element 4 is transmitted to the compression element 3. The piston 13 of the compression element 3 reciprocates in the cylinder 11 by the crank pin 12 of the rotating shaft 5 to compress the refrigerant. The oil in the oil reservoir 7 is slid by the centrifugal force generated by the rotation of the rotary shaft 5 from the oil pickup 21 attached to the lower end of the rotary shaft 5 through the oil supply hole 17 to the bearing 15 and the compression element 3 of the motor case 2. Supplied to the department.
[0013]
The center 30 of the oil supply hole 17A on the oil pickup 21 side is provided to be shifted from the center 50 of the rotary shaft 5 by 0.91 mm, and the oil supply hole 17 is at least 2.3 ° with respect to the rotary shaft 5 in a substantially shifted direction, preferably, By being provided at an angle of 2.3 ° to 3.4 °, the centrifugal force against the oil generated by the rotation of the rotating shaft 5 increases, and the rotation speed of the motor is changed by using an inverter (for example, 25 degrees). Even if the number of rotations of the motor decreases, the centrifugal force against the oil generated by the rotation of the rotating shaft 5 increases, so that the oil rises well and the oil can be stably supplied to each sliding portion. It is possible to prevent the sliding portion from being oilless. As a result, the reliability is improved, and the length L of the rotating shaft 5 can be reduced to reduce the size.
[0014]
The shift distance of the center 30 of the oil supply hole 17A from the center 50 of the rotary shaft 5 is 0.91 mm in the above example, but the lower limit of the shift distance may be 0, and the upper limit is not particularly limited. The strength of the shaft 5 may be taken into consideration so that the oil is properly lifted.
[0015]
In the above example, the oil supply hole 17 is inclined at an angle of 2.3 ° or more, preferably 2.3 ° to 3.4 °, more preferably 2.85 ° to 3.35 ° with respect to the rotating shaft 5. Although an example has been shown, the lower limit value of the inclination angle needs to be 2.3 °. If the lower limit is less than 2.3 °, the centrifugal force on the oil generated by the rotation of the rotating shaft 5 is small, and there is a possibility that the oil rise is not improved. If the upper limit value of the inclination angle is 3.4 ° or more, there is no particular limitation because the oil rise of the oil is improved, but if the upper limit value is too large, the strength of the rotating shaft 5 decreases. It is preferable to decide appropriately in consideration of the above.
[0016]
As a specific example, for example, when a lubrication hole having an inner diameter of about 8.7 mm is provided on a rotating shaft having a length of about 85 mm and an outer diameter of about 18 mm made of a cast material FC300, the center 30 of the lubricating hole 17A is positioned from the center 50 of the rotating shaft 5. An example is a shift distance of 0.91 mm and an inclination angle of the oil supply hole 17 with respect to the rotating shaft 5 of 2.3 ° to 3.4 °, preferably 2.85 °.
[0017]
If the inside diameter of the oil supply hole 17 is too small, outgassing deteriorates, and if it is too large, the strength of the rotating shaft decreases. Therefore, it is preferable to appropriately determine the oil type, the type and size of the compressor, operating conditions, and the like.
[0018]
The refrigerant used in the present invention is not particularly limited, and does not contain a chlorine group, for example, difluoromethane (HFC-32, R-32), 1,1-difluoroethane (HFC-152a, R-152a). , Trifluoromethane (HFC-23, R-23), pentafluoroethane (HFC-125, R-125), 1,1,1,2-tetrafluoroethane (HFC-134a, R-134a), 1,1 , 1-trifluoroethane (HFC-143a, R-143a), fluorocarbon-based refrigerant containing no chlorine group and hydrogen (FC-based refrigerant), hydrocarbon-based refrigerants such as methane, ethane, propane, butane, pentane and hexane; A natural refrigerant such as carbon dioxide can be used.
[0019]
The oil used in the present invention may be a natural product such as naphthenic oil, paraffin oil, or alkylbenzene oil or a natural product-derived product, a polyether-based oil, a synthetic product such as a polyol ester-based oil, or a mixture thereof. Not something.
Oils used in the present invention include copper deactivators such as benzotriazole, sulfur-based extreme pressure additives, halogen-based extreme pressure additives, phosphorus-based extreme pressure additives, organometallic compound-based extreme pressure additives, and the like. An effective amount of other known additives such as an extreme pressure additive composed of a combination of the above can be blended.
[0020]
It should be noted that the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the appended claims.
For example, in the above description, the vertical type reciprocating compressor was described, but the present invention is not particularly limited in the type of the compressor, and specifically, a rotary compressor, a vibration compressor, a multi-vane rotary compressor A compressor, a scroll compressor, or the like may be used.
[0021]
【The invention's effect】
An oil supply device for a hermetic compressor according to claim 1 of the present invention supplies an electric element and a compression element in an airtight container having an oil reservoir at a bottom portion, and supplies oil from the oil reservoir to a sliding portion of the compression element. A rotary shaft having a hole and transmitting the rotational force of the electric element to the compression element is housed, and an oil pickup immersed in the oil of the oil reservoir and locked in the oil supply hole is provided at the lower end of the rotary shaft. In the oil supply device for the hermetic compressor provided, a center of the oil supply hole on the oil pickup side is provided to be shifted from a center of the rotation shaft, and the oil supply hole is substantially offset from the rotation shaft with respect to the rotation shaft. The oil supply hole on the oil pick-up side is shifted from the center of the rotation shaft, and the oil supply hole is provided in a substantially shifted direction. With a simple configuration of being inclined at an angle of 2.3 ° or more with respect to the rotation shaft, even if the rotation speed of the motor is reduced by changing the rotation speed of the motor by using the inverter, the rotation of the rotation shaft is reduced. The resulting centrifugal force on the oil increases, and the oil can be supplied stably to each sliding part and each sliding part can be prevented from becoming oil-less. And a remarkable effect that the reliability is improved.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram illustrating an embodiment of an oil supply device for a hermetic compressor according to the present invention.
FIG. 2 is an explanatory view showing a cross-sectional structure of a rotary shaft and an oil supply hole of the oil supply device of the hermetic compressor shown in FIG.
FIG. 3 is an explanatory view showing a cross-sectional structure of a rotary shaft and an oil supply hole of an oil supply device of a conventional hermetic compressor.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Closed container 2 Motor case 3 Compression element 4 Electric element 5 Rotating shaft 6 Elastic support device 7 Oil reservoir 8 Winding 9 Stator 10 Rotor 11 Cylinder 12 Crank pin 13 Piston 14 Valve seat 15 Cylinder head 16 Bearing 17 Oil supply hole 21 Oil pickup 22 Oil outlet 23 Gas vent hole

Claims (1)

It has an electric element and a compression element in an airtight container having an oil reservoir at the bottom, and an oil supply hole for supplying oil from the oil reservoir to a sliding portion of the compression element, and transmits the rotational force of the electric element to the compression element. In the oil supply device of a hermetic compressor in which a rotary shaft is housed, and an oil pickup is provided at the lower end of the rotary shaft, which is immersed in oil in an oil reservoir and locked in an oil supply hole.
The center of the oil supply hole on the oil pickup side is shifted from the center of the rotation shaft, and the oil supply hole is inclined at an angle of at least 2.3 ° with respect to the rotation shaft in a direction substantially shifted. An oil supply device for a hermetic compressor characterized by the above-mentioned.

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