JP2008501080A - Hermetic compressor - Google Patents

Abstract

A refrigerant and refrigeration oil were sealed in a sealed container, and an electric element composed of a rotor and a stator was accommodated in the sealed container, and a compression element driven by the electric element was accommodated in the upper part of the sealed container. The compression element includes a shaft that is disposed in the vertical direction and has a rotor fitted thereto, and a bearing that supports the shaft. Further, a first oil pump provided in the lower part of the shaft and opened in the refrigerating machine oil, and a first oil pump formed above the first oil pump and formed by a spiral groove provided on the outer periphery of the shaft and an inner wall surface of the rotor. 2 oil pumps and a third oil pump provided above the second oil pump and formed by a spiral groove provided on the outer periphery of the shaft and an inner peripheral surface of the bearing.

Description

  The present invention relates to a hermetic compressor used in a refrigeration cycle such as a refrigerator-freezer.

  In recent years, with regard to hermetic compressors used in household refrigerator-freezers, reduction of power consumption and noise reduction have been strongly desired. Under these circumstances, many attempts have been made to reduce the viscosity of refrigeration oil and the rotation of a compressor driven by an inverter (for example, about 1200 rpm in the case of a household refrigerator). In a hermetic compressor, it is important to supply sufficient refrigerating machine oil to sliding parts such as bearings, connecting rods, and pistons, and an oil pump that can stably supply oil even during low-speed rotation is effective as an elemental technology. is there.

  As a conventional oil pump of this type, there is an oil pump that collects oil at a position where the rotor has a large turning radius where a strong centrifugal force can be obtained. For example, see JP-T-9-512315.

Hereinafter, the above-described conventional hermetic compressor will be described with reference to the drawings.
FIG. 15 is a longitudinal sectional view of a conventional hermetic compressor, and FIG. 16 is a partially enlarged view of this conventional hermetic compressor. Referring to these drawings, a conventional compressor includes a sealed container 1 filled with a refrigerant 2 and a refrigerating machine oil 3.

  The electric element 11 includes a stator 12 that is electrically connected to an external power source (not shown), and a rotor 13 that is disposed inside the stator 12, and the stator 12 and the rotor 13. A predetermined gap is provided between the two.

  The compression element 21 includes a shaft 22 having a main shaft portion 22a fitted with a rotor 13 and an eccentric shaft portion 22b, a cylinder block 23 fixed above the stator 12 and forming a compression chamber 23a, and a cylinder Provided in the block 23 is provided with a bearing 24 that supports the main shaft portion 22a, a piston 25 that reciprocates in the compression chamber 23a, and a connecting means 26 that connects the piston 25 and the eccentric shaft portion 22b. The compression mechanism is formed.

Next, the configuration of the oil supply mechanism will be described in detail.
An oil pump 31 immersed in the refrigerating machine oil 3 is formed at the lower end of the main shaft portion 22 a of the shaft 22.

  The rotor 13 is machined with an oil introduction hole 32 that connects the inner wall fitted to the main shaft portion 22a and a position with a large rotation radius on the upper surface side of the rotor 13, and the oil introduction hole is formed from the upper end of the oil pump 31 through the communication hole 33. 32.

  The oil guide pipe 34 is inserted and fixed in the upper surface side opening of the rotor 13 of the oil guide hole 32, and the oil collecting means 35 that receives the refrigerating machine oil 3 attached to the bearing 24 and discharged from the oil guide pipe 34 is collected in the oil collecting means 35. Supply means 36 for supplying the refrigerating machine oil 3 to a sliding portion formed by the main shaft portion 22 a and the bearing 24 is provided.

The operation of the hermetic compressor configured as described above will be described below.
When the stator 12 is energized from an external power source, the rotor 13 rotates with the shaft 22. Accordingly, the eccentric movement of the eccentric shaft portion 22b causes the piston 25 to reciprocate in the compression chamber 23a via the connecting means 26 to perform a predetermined compression operation for compressing the suction gas.

  As the shaft 22 rotates, the main shaft portion 22a rotates, and the refrigeration oil 3 that has moved up the oil pump 31 passes through the communication hole 33 and moves up the oil guide hole 32 and the oil guide pipe 34 by centrifugal force.

The refrigerating machine oil 3 discharged from the oil guide pipe 34 is poured into the oil collecting means 35.
The refrigerating machine oil 3 collected in the oil collecting means 35 lubricates the sliding portion formed by the main shaft portion 22 a and the bearing 24 by the supply means 36.

  In addition, in order to improve efficiency for reducing power consumption, reduce vibration, and reduce noise, the electric element is changed from an induction motor to a two-pole permanent magnet type motor with a permanent magnet built into the rotor. (For example, refer to Japanese Patent Application Laid-Open No. 2001-73948), there is a hermetic compressor having a configuration in which a mechanical unit is disposed above (for example, refer to Japanese Patent Application Laid-Open No. 2000-110723).

Hereinafter, the conventional hermetic compressor will be described with reference to the drawings.
FIG. 17 shows a longitudinal sectional view of a conventional hermetic compressor described in Japanese Patent Laid-Open No. 2001-73948 described above. As shown in FIG. 17, the sealed container 51 houses an electric element 54 including a stator 52 and a rotor 53, and a compression element 55 driven by the electric element 54. To save. The shaft 60 includes a main shaft portion 61 to which the rotor 53 is fixed and an eccentric shaft portion 62 that is formed eccentric to the main shaft portion 61. The cylinder block 64 has a substantially cylindrical compression chamber 65, and a main bearing 67 made of an aluminum-based material that is a non-magnetic material is fixed. The piston 69 is inserted into the compression chamber 65 of the cylinder block 64 so as to be slidable back and forth, and is connected to the eccentric shaft portion 62 by a connecting means 70.

  The electric element 54 is a two-pole permanent magnet type electric motor composed of a stator 52 in which a winding is wound around a stator core 75 made of laminated electromagnetic steel sheets and a rotor 53 having a permanent magnet 77 built therein. A protective end plate 78 that prevents the permanent magnet 77 from falling off is fixed to the rotor core 76.

  A hollow bore 79 is provided at the end of the rotor core 76 facing the compression element 55, and the main bearing 67 extends inside the hollow bore 79.

The operation of the hermetic compressor configured as described above will be described below.
The rotor 53 of the electric element 54 rotates the shaft 60, and the rotational movement of the eccentric shaft portion 62 is transmitted to the piston 69 via the connecting means 70, so that the piston 69 reciprocates in the compression chamber 65. As a result, the refrigerant gas is sucked and compressed into the compression chamber 65 from a cooling system (not shown) and then discharged again to the cooling system.

  Next, the flow and loss of magnetic flux when the rotor 53 rotates will be described. Since the main bearing 67 is formed of a non-magnetic material, no magnetic attraction force acts between the inner periphery of the bore 79 and the main bearing 67, so that no loss torque is generated, and the magnetic flux from the permanent magnet 77 is Since the main bearing 67 is a non-magnetic material, the main bearing 67 is not attracted to the main bearing 67 and almost passes only through the rotor core 76. Therefore, almost no iron loss (especially eddy current loss) occurs in the main bearing 67, and high efficiency can be achieved.

  FIG. 18 shows a longitudinal sectional view of a conventional hermetic compressor described in the above-mentioned Japanese Patent Application Laid-Open No. 2000-110723.

  As shown in FIG. 18, the sealed container 81 accommodates an electric element 84 including a stator 82 and a rotor 83 and a compression element 85 driven by the electric element 84, and the refrigerator oil 86 is contained in the sealed container 81. To save. The shaft 87 has a main shaft portion 88 in which the rotor 83 is press-fitted and fixed, and an eccentric shaft portion 89 formed eccentric to the main shaft portion 88.

  The cylinder block 94 has a substantially cylindrical compression chamber and a main bearing 96 that rotatably supports the main shaft portion 88. The piston 97 is inserted into the compression chamber of the cylinder block 94 so as to be slidable back and forth, and is connected to the eccentric shaft portion 89 by connecting means 98.

  Oil supply passages 90, 91 are provided inside the shaft 87, and the lower end of the main shaft portion 88 communicates with the vicinity of the upper end of the oil supply passage 90 and spirals while inclining in the counter-rotating direction of the shaft 87 upward. A spiral groove 92 engraved in a shape is formed. The upper end of the spiral groove 92 communicates with the vicinity of the lower end of the oil supply passage 91. An oil cone 93 having one end opened in the refrigerating machine oil 86 and the other end communicating with the oil supply passage 90 is fixed to the lower end portion of the main shaft portion 88. The compression element 85 and the electric element 84 are integrated and elastically supported in the sealed container 81 by a spring 95 provided at the lower part of the electric element 84.

The operation of the hermetic compressor configured as described above will be described below.
The rotor 83 of the electric element 84 rotates the shaft 87, and the rotational movement of the eccentric shaft portion 99 is transmitted to the piston 97 via the connecting means 98, whereby the piston 97 reciprocates in the compression chamber. Thus, the refrigerant gas is sucked and compressed from the cooling system (not shown) into the compression chamber, and then discharged again to the cooling system.

  On the other hand, the oil cone 93 performs a pumping action by the rotation of the shaft 87. Due to the pumping action of the oil cone 93, the refrigerating machine oil 86 at the bottom of the sealed container 81 is raised upward through the oil supply passage 90. The refrigerating machine oil 86 reaching the upper portion of the oil supply passage 90 is introduced into the spiral groove 92. Since the spiral groove 92 is inclined in the same direction as the inertial force acting in the direction opposite to the rotation direction of the shaft 87, a large upward conveying force is newly exerted on the refrigerating machine oil 86.

  The refrigerating machine oil 86 is raised upward in the spiral groove 92 and supplied to the sliding portion of the shaft 87. The refrigerating machine oil 86 reaching the upper end of the spiral groove 92 is introduced into the oil supply passage 91 and supplied to a sliding portion such as the eccentric shaft portion 89 to perform lubrication.

  Further, since the piston 97 reciprocates, the vibration of the compression element 85 in the vicinity of the piston 97 increases, but the vibration of the lower portion of the electric element 84 that is far from the piston 97 decreases. Since the compression element 85 and the electric element 84 are integrally elastically supported by the spring 95 at the lower part of the electric element 84 having a small vibration, the vibration transmitted to the sealed container 81 through the spring 95 is suppressed to be small and the vibration is small. It can be a hermetic compressor.

  However, the configuration described in the above-mentioned Japanese National Publication No. 9-512315 has a problem that the manufacturing cost of the hermetic compressor increases because a complicated oil supply path is formed in the rotor. In addition, oil transfer pipes, oil collection means, and supply means are required to move the refrigeration oil against the centrifugal force from a position with a large turning radius to a position with a small turning radius. There was a problem of concern about becoming.

  In addition, when the two-pole permanent magnet type motor used for high efficiency in Japanese Patent Laid-Open No. 2001-73948 is applied to a low-vibration hermetic compressor shown in Japanese Patent Laid-Open No. 2000-110723, the main shaft portion 88 includes Since the oil supply passage 90 having a large cross-sectional area is formed, there is a portion where a magnetic path cannot be formed inside the rotor core 76, and only a narrow magnetic path can be formed partially and the magnetic resistance is reduced. Therefore, the amount of magnetic flux generated by the permanent magnet 77 of the rotor core 76 is reduced as compared with the case where the oil supply passage 90 is not provided, and the loss is increased.

  The present invention has been made in view of such problems of the prior art, and an object of the present invention is to provide an inexpensive and highly reliable hermetic compressor that can stably supply oil during low-speed rotation.

  Another object of the present invention is to increase efficiency by increasing the amount of magnetic flux generated by a permanent magnet when a two-pole permanent magnet motor is applied to a hermetic compressor with a compression element disposed on the top. It is intended to provide a hermetic compressor with low vibration and high efficiency.

  In order to achieve the above object, the present invention includes a sealed container in which a refrigerant and refrigerating machine oil are enclosed, and an electric element including a rotor and a stator is accommodated in the hermetic container, and is driven by the electric element. An element is accommodated in the upper part of the closed container, and the compression element includes a shaft arranged in a vertical direction and fitted with the rotor, and a bearing that supports the shaft, and is provided in a lower part of the shaft. A first oil pump that opens into the refrigerating machine oil, and a second oil pump that is provided above the first oil pump and that is formed by a spiral groove provided on the outer periphery of the shaft and an inner wall surface of the rotor. And a third oil pump provided above the second oil pump and formed by a spiral groove provided on the outer periphery of the shaft and an inner peripheral surface of the bearing.

  According to the present invention, the refrigerating machine oil that has risen due to centrifugal force in the first oil pump is lifted by the second oil pump, and the third oil forms a viscous pump having a strong conveying force even at low rotation. By reaching the pump, stable oil supply can be performed at low speed rotation, and the number of parts can be reduced and the structure can be configured by simple processing. Therefore, a highly reliable and inexpensive hermetic compressor can be provided.

  In addition, when the spiral groove of the second oil pump and the spiral groove of the third oil pump are continuously formed, the spiral groove can be continuously processed on the outer periphery of the shaft, so that mass productivity can be improved.

  Further, when the spiral groove of the second oil pump and the spiral groove of the third oil pump are opened in a first gap formed between the rotor and the bearing, the space between the rotor and the bearing is increased. Therefore, noise can be reduced and power consumption can be reduced.

  In addition, if the first gap is set to 0.5 mm or less over the entire circumference, the refrigerating machine oil flowing out from the first gap is reduced and the lubrication to the sliding part can be increased, so that the reliability can be further improved. I can do it.

  In addition, when a bore portion is provided on the upper end surface of the rotor to extend the bearing, and a second gap is formed between the inner circumferential surface of the bore portion and the outer circumferential surface of the bearing, the second gap The refrigerating machine oil accumulated inside becomes a resistance, and the refrigerating machine oil can be prevented from flowing out from the second gap.

  Further, when a portion of 1.0 mm or less is provided in the second gap over the entire circumference, the refrigerating machine oil flowing out from the second gap is reduced due to the resistance due to the viscosity of the refrigerating machine oil, and the lubrication to the sliding portion is increased. I can do it.

  Moreover, when the depth of the bore part is set to 5.0 mm or more, it is possible to further suppress the refrigerating machine oil accumulated in the second gap from flowing out from the second gap.

  Further, if a washer that can be elastically deformed in the axial direction is interposed in the first gap, the first gap becomes almost zero over the entire circumference, so that the refrigerating machine oil flowing out of the first gap is reduced. It can be drastically reduced and more oil can be supplied to the sliding part.

  In addition, when the magnetic center of the rotor is arranged so as to be shifted downward from the magnetic center of the stator and the rotor is lifted by a magnetic attraction force during operation, the first gap is formed around the entire circumference during operation. Therefore, the refrigerating machine oil flowing out from the first gap is drastically reduced, and the oil supply to the sliding portion can be increased.

  Further, according to another aspect of the present invention, refrigerating machine oil is stored in a sealed container, and an electric element composed of a rotor and a stator and a compression element driven by the electric element are accommodated in the sealed container, The compression element includes a shaft having an eccentric shaft portion and a main shaft portion, a main bearing that supports the main shaft portion, a first oil pump that is provided at a lower portion of the shaft and opens into the refrigerating machine oil, and the first oil A second oil pump provided above the pump and formed by a spiral groove provided on the outer periphery of the shaft and an inner wall surface of the rotor; provided above the second oil pump; provided on the outer periphery of the shaft. A third oil pump formed by a spiral groove and an inner peripheral surface of the main bearing, and the electric element is a two-pole permanent magnet type electric motor having a permanent magnet built in a rotor core of the rotor. Special To.

  According to this aspect of the present invention, there is no large space inside the main shaft portion as in the conventional oil supply passage, and there is almost no obstruction of the magnetic path inside the rotor core, and the magnetic path can be formed widely. Therefore, the amount of magnetic flux generated inside the rotor core is increased, the loss is reduced, and the efficiency of the electric element can be improved.

  In addition, when the main bearing is configured so as not to intersect with a plane that includes the compression element side end portion of the rotor core and is substantially orthogonal to the main shaft axis, the main bearing is conventionally provided for insertion into the rotor core. Since there is no bore portion and the narrowing of the magnetic path by the bore portion is eliminated, the amount of magnetic flux inside the rotor core is further increased and the efficiency is further improved.

  Further, when a sub-shaft portion provided coaxially with the main shaft portion with the eccentric shaft portion interposed therebetween and a sub-bearing that pivotally supports the sub-shaft portion, the sub-bearing fundamentally regulates the inclination of the shaft, Even if the length of the main bearing is shortened and the main bearing is not inserted into the rotor core, the inclination of the shaft remains almost unchanged, and the shaft and main bearing or sub-bearing are not twisted. And the efficiency can be improved and the noise can be lowered.

  Further, a two-pole permanent magnet type electric motor has a plurality of conductor bars of a squirrel-cage-shaped conductor on the outer periphery of the rotor core, and a self equipped with a rotor in which a plurality of permanent magnets are embedded. In the case of a starting permanent magnet type synchronous motor, a synchronous motor capable of obtaining high efficiency can be employed.

  In addition, it is preferable to form the permanent magnet with a rare earth magnet, a strong magnetic force can be obtained, and the motor can be reduced in size and weight and the hermetic compressor can be reduced in size and weight.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is a longitudinal sectional view of a hermetic compressor according to Embodiment 1 of the present invention, and FIG. 2 is an enlarged view of a main part of the hermetic compressor according to the same embodiment.

  Referring to FIGS. 1 and 2, the sealed container 101 is filled with a refrigerant 102 and refrigerating machine oil 103 is stored. Here, the refrigerant 102 is R600a which is a hydrocarbon refrigerant, and the refrigerating machine oil 103 is compatible with the refrigerant 102, for example, synthetic oil, mineral oil, polyol ester oil, or the like.

  The electric element 111 includes a stator 112 that is electrically connected to an external power source (not shown), and a rotor 113 that is disposed with a predetermined gap from the inside of the stator 112.

  The compression element 121 includes a shaft 122 having a main shaft portion 122a and an eccentric shaft portion 122b to which a rotor 113 is fitted, a cylinder block 123 fixed above the stator 112 and forming a compression chamber 123a, and a cylinder A bearing 124 provided in the block 123 and rotatably supporting the main shaft portion 122a, a piston 125 reciprocating in the compression chamber 123a, and a connecting means 126 for connecting the piston 125 and the eccentric shaft portion 122b are provided. The reciprocating compression mechanism is formed.

  A first gap 131 is formed between the lower end surface of the bearing 124 and the upper end surface of the rotor 113. The first gap 131 is formed to be 0.5 mm or less over the entire circumference.

Next, the configuration of the oil supply mechanism will be described in detail.
The first oil pump 141 is immersed in the refrigerating machine oil 103 and inclined upward from the lower end surface of the main shaft portion 122a to the inside, the stirring plate 143 press-fitted into the inclined hole 142, and penetrated through the center. It is composed of an end plate 144 that has a through hole 144a and is locked to the opening of the inclined hole 142, and forms a centrifugal pump.

  The second oil pump 151 is provided above the first oil pump 141. The second oil pump 151 includes a spiral groove 152 provided on the outer periphery of the main shaft portion 122a and an inner wall surface of the rotor 113, and forms an inertia pump. The first oil pump 141 and the second oil pump 151 communicate with each other through a through hole 153.

  The third oil pump 161 is provided above the second oil pump 151, and includes a spiral groove 162 continuously formed with the spiral groove 152 provided on the outer periphery of the main shaft portion 122a, and an inner peripheral surface of the bearing 124. A viscous pump is formed.

  The spiral groove 152 and the spiral groove 162 are formed as a spiral groove having the same pitch angle as a continuous groove across the first gap 131.

The operation and action of the hermetic compressor configured as described above will be described below.
When the stator 112 is energized from an external power source, the rotor 113 rotates with the shaft 122. Accordingly, the eccentric movement of the eccentric shaft portion 122b causes the piston 125 to reciprocate in the compression chamber 123a via the connecting means 126 to perform a predetermined compression operation for compressing the suction gas.

Next, the operation of refueling will be described.
In the first oil pump 141, as the main shaft portion 122a rotates, the refrigerating machine oil 103 rotates in the inclined hole 142 by the stirring plate 143 immersed in the refrigerating machine oil 103, and the refrigerating machine oil 103 is caused by the centrifugal force generated here. It rises along the inner wall surface of the inclined hole 142.

  Here, the position of the through hole 153 may be within a range where the rotor 113 of the main shaft portion 122a is fitted, and the diameter of the inclined hole 142 of the first oil pump 141 that supplies oil by centrifugal force is increased. The capacity can be increased, and the first oil pump 141 only needs to raise a slight head up to the second oil pump 151. For example, the refrigerating machine oil 103 reliably reaches the through hole 153 even at a low rotation of 20 Hz.

  The refrigerating machine oil 103 that has passed through the through hole 153 from the first oil pump 141 and led to the second oil pump 151 is caused by an inertial force generated upward due to the inclination in the spiral groove 152, so that the spiral groove 152 of the second oil pump 151. Rise inside.

  The refrigerating machine oil 103 passing through the first gap 131 and reaching the third oil pump 161 rises in the spiral groove 162 due to a viscous force generated by a relative rotational difference between the fixed bearing 124 and the rotating main shaft portion 122a. To do.

  Here, as described above, the third oil pump 161 forms a viscous pump that uses a viscous force generated by a relative rotational difference between the bearing 124 and the rotating main shaft portion 122a. In general, since the viscous pump uses viscous force and generates a strong conveying force, the refrigerating machine oil 103 is reliably pushed up even at a low rotation of 20 Hz, for example.

  The refrigerating machine oil 103 that has reached the third oil pump 161 lubricates the sliding surface formed by the outer peripheral surface of the main shaft portion 122a and the inner peripheral surface of the bearing 124, and is further sent to the eccentric shaft portion 122b.

  Therefore, according to the present embodiment, the refrigerating machine oil 103 can be reliably fed into each sliding portion even at a low rotation operation, and a hermetic compressor having high reliability can be realized.

  Further, in the present embodiment, the parts newly required for forming the oil pump are only the stirring plate 143 and the end plate 144 that can be formed at low cost from a pressing material of an iron plate or the like. Further, since the spiral groove 152 constituting the second oil pump 151 and the spiral groove 162 constituting the third oil pump 161 are formed by continuous spiral grooves having the same pitch angle, the spiral groove 152 is spirally formed on the outer periphery of the main shaft portion 122a. Groove processing can be performed continuously at a constant feed rate, and mass productivity can be improved.

  In addition, since the first gap 131 is provided between the lower end surface of the bearing 124 and the upper end surface of the rotor 113, no sliding occurs between the bearing 124 and the rotor 113. There is no dynamic loss, and the effect of reducing noise and reducing power consumption can be obtained.

  When the refrigerating machine oil 103 passes through the first gap 131, a part of the refrigerating machine oil 103 flows out from the first gap 131 radially due to centrifugal force and hydraulic pressure. However, in the present embodiment, the first gap 131 is set to 0.5 mm or less over the entire circumference, and it has been confirmed that there is no significant decrease in the amount of oil supplied when the gap is this level.

  In the present embodiment, the diameter of the inclined hole 142 is exemplified and described. However, it is needless to say that the same action and effect can be obtained even when the inclination angle of the hole 142 is increased.

Embodiment 2. FIG.
FIG. 3 is a longitudinal sectional view of the hermetic compressor according to the second embodiment of the present invention, and FIG. 4 is an enlarged view of a main part of the hermetic compressor according to the second embodiment.

  In addition, about the same structure as Embodiment 1, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  Referring to FIGS. 3 and 4, the electric element 180 includes a stator 112 electrically connected to an external power source (not shown), and a rotation arranged with a predetermined gap from the inside of the stator 112. It consists of a child 171.

  The compression element 185 includes a shaft 122 having a main shaft portion 122a fitted with a rotor 171 and an eccentric shaft portion 122b, a cylinder block 183 fixed above the stator 112 and forming a compression chamber 183a, and a cylinder A bearing 184 that is provided in the block 183 and rotatably supports the main shaft portion 122a, a piston 125 that reciprocates in the compression chamber 183a, and a connecting means 126 that connects the piston 125 and the eccentric shaft portion 122b. The reciprocating compression mechanism is formed.

  The rotor 171 has a bore portion 172 from which the bearing 184 extends on the upper surface side of the rotor 171, and a second gap 173 is formed between the inner peripheral surface of the bore portion 172 and the outer peripheral surface of the bearing 184. Yes.

Next, the configuration of the oil supply mechanism will be described in detail.
The first oil pump 141 is immersed in the refrigerating machine oil 103 and inclined upward from the lower end surface of the main shaft portion 122a to the inside, the stirring plate 143 press-fitted into the inclined hole 142, and penetrated through the center. It has a through hole 144a and is composed of an end plate 144 locked to the opening of the inclined hole 142, forming a centrifugal pump.

  The second oil pump 151 is provided above the first oil pump 141. The second oil pump 151 includes a spiral groove 152 provided on the outer periphery of the main shaft portion 122a and an inner wall surface of the rotor 171, and forms an inertia pump. The first oil pump 141 and the second oil pump 151 communicate with each other through a through hole 153.

  The third oil pump 161 is provided above the second oil pump 151, and includes a spiral groove 162 continuously formed with the spiral groove 152 provided on the outer periphery of the main shaft portion 122a, and an inner peripheral surface of the bearing 184. A viscous pump is formed.

  The spiral groove 152 and the spiral groove 162 are formed as a spiral groove having the same pitch angle as a continuous groove across the first gap 131.

The operation and action of the hermetic compressor configured as described above will be described below.
When the stator 112 is energized from an external power source, the rotor 171 rotates with the shaft 122. Accordingly, the eccentric movement of the eccentric shaft portion 122b performs a predetermined compression operation in which the piston 125 is reciprocated in the compression chamber 183a via the connecting means 126 to compress the suction gas.

Next, the operation of refueling will be described.
In the first oil pump 141, as the main shaft portion 122a rotates, the refrigerating machine oil 103 rotates in the inclined hole 142 by the stirring plate 143 immersed in the refrigerating machine oil 103, and the refrigerating machine oil 103 is caused by the centrifugal force generated here. It rises along the inner wall surface of the inclined hole 142.

  Here, the position of the through hole 153 may be in a range where the rotor 171 of the main shaft portion 122a is fitted, and the diameter of the inclined hole 142 of the first oil pump 141 that supplies oil by centrifugal force is increased. The capacity can be increased, and the first oil pump 141 only needs to raise a slight head up to the second oil pump 151. For example, the low-speed refrigerating machine oil 103 of 20 Hz reaches the through hole 153 with certainty.

  The refrigerating machine oil 103 that has passed through the through hole 153 from the first oil pump 141 and led to the second oil pump 151 is caused by an inertial force generated upward due to the inclination in the spiral groove 152, so that the spiral groove 152 of the second oil pump 151. Rise inside.

  The refrigerating machine oil 103 that has passed through the first gap 131 and reached the third oil pump 161 rises in the spiral groove 162 due to a viscous force generated by a relative rotational difference between the fixed bearing 184 and the rotating main shaft portion 122a. To do.

  Here, as described above, the third oil pump 161 forms a viscous pump that uses a viscous force generated by a relative rotational difference between the bearing 184 and the rotating main shaft portion 122a. In general, since a viscous pump uses a viscous force, a strong conveying force is generated, so that the refrigerating machine oil 103 is reliably pushed up even at a low rotation of 20 Hz, for example.

  The refrigerating machine oil 103 that has reached the third oil pump 161 lubricates the sliding surface formed by the outer peripheral surface of the main shaft portion 122a and the inner peripheral surface of the bearing 184, and is further sent to the eccentric shaft portion 122b.

  Therefore, according to the present embodiment, the refrigerating machine oil 103 can be reliably fed into each sliding portion even at a low rotation operation, and a hermetic compressor having high reliability can be realized.

  Further, in the present embodiment, the parts newly required for forming the oil pump are only the stirring plate 143 and the end plate 144 that can be formed at low cost from a pressing material of an iron plate or the like. Further, since the spiral groove 152 constituting the second oil pump 151 and the spiral groove 162 constituting the third oil pump 161 are formed by continuous spiral grooves having the same pitch angle, the spiral groove 152 is spirally formed on the outer periphery of the main shaft portion 122a. Groove processing can be performed continuously at a constant feed rate, and mass productivity can be improved.

  Further, since the first gap 131 is provided between the lower end surface of the bearing 184 and the upper end surface of the rotor 171, no sliding occurs between the bearing 184 and the rotor 171. There is no dynamic loss, and the effect of reducing noise and reducing power consumption can be obtained.

  When the refrigerating machine oil 103 passes through the first gap 131, a part of the refrigerating machine oil 103 flows out from the first gap 131 radially due to centrifugal force and hydraulic pressure. However, in the present embodiment, the gravity of the refrigerating machine oil 103 accumulated in the second gap 173 becomes resistance, and the refrigerating machine oil 103 flowing out from the second gap 173 can be reduced, and as a result, Furthermore, reliability can be improved.

  Further, if the second gap 173 between the inner peripheral surface of the bore portion 172 and the outer peripheral surface of the bearing 184 is large, the refrigerating machine oil 103 flowing out from the gap increases, and the amount of oil supply decreases. It has been confirmed that when a portion of 1.0 mm or less is provided in the gap 173 over the entire circumference, the decrease in the amount of oil supply suddenly decreases.

  Similarly, if the depth of the bore portion 172 is 5.0 mm or more over the entire circumference, the refrigerating machine oil 103 accumulated in the second gap 173 can be prevented from flowing out due to gravity. It has been confirmed that there is almost no decrease in the amount of oil supply.

  In the present embodiment, the diameter of the inclined hole 142 is exemplified and described. However, it is needless to say that the same action and effect can be obtained even when the inclination angle of the hole 142 is increased.

Embodiment 3 FIG.
FIG. 5 is a longitudinal sectional view of a hermetic compressor according to Embodiment 3 of the present invention, and FIG. 6 is an enlarged view of a main part of the hermetic compressor according to the same embodiment.

  In addition, about the same structure as Embodiment 1, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  Referring to FIGS. 5 and 6, the first oil pump 141 is immersed in the refrigerating machine oil 103 and is inclined into the inclined hole 142 and the inclined hole 142 inclined upward from the lower end surface of the main shaft portion 122 a. It is composed of a stirring plate 143 and an end plate 144 having a hole 144a penetrating in the center and being engaged with the opening of the inclined hole 142, thereby forming a centrifugal pump.

  The second oil pump 151 is provided above the first oil pump 141. The second oil pump 151 includes a spiral groove 152 provided on the outer periphery of the main shaft portion 122a and an inner wall surface of the rotor 113, and forms an inertia pump. The first oil pump 141 and the second oil pump 151 communicate with each other through a through hole 153.

  The third oil pump 161 is provided above the second oil pump 151, and includes a spiral groove 162 continuously formed with the spiral groove 152 provided on the outer periphery of the main shaft portion 122a, and an inner peripheral surface of the bearing 124. A viscous pump is formed.

  The spiral groove 152 and the spiral groove 162 are formed as a spiral groove having the same pitch angle as a continuous groove across the first gap 131.

  A first gap 131 formed between the lower end surface of the bearing 124 and the upper end surface of the rotor 113 is provided with a washer 181 that can be elastically deformed in the axial direction.

The operation and action of the hermetic compressor configured as described above will be described below.
When the stator 112 is energized from an external power source, the rotor 113 rotates with the shaft 122. Accordingly, the eccentric movement of the eccentric shaft portion 122b causes the piston 125 to reciprocate in the compression chamber 123a via the connecting means 126 to perform a predetermined compression operation for compressing the suction gas.

Next, the operation of refueling will be described.
In the first oil pump 141, as the main shaft portion 122a rotates, the refrigerating machine oil 103 rotates in the inclined hole 142 by the stirring plate 143 immersed in the refrigerating machine oil 103, and the refrigerating machine oil 103 is caused by the centrifugal force generated here. It rises along the inner wall surface of the inclined hole 142.

  Here, the position of the through hole 153 may be within a range where the rotor 113 of the main shaft portion 122a is fitted, and the diameter of the inclined hole 142 of the first oil pump 141 that supplies oil by centrifugal force is increased. The capacity can be increased, and the first oil pump 141 only needs to raise a slight head up to the second oil pump 151. For example, the refrigerating machine oil 103 reliably reaches the through hole 153 even at a low rotation of 20 Hz.

  The refrigerating machine oil 103 that has passed through the through hole 153 from the first oil pump 141 and led to the second oil pump 151 is caused by an inertial force generated upward due to the inclination in the spiral groove 152, so that the spiral groove 152 of the second oil pump 151. Rise inside.

  The refrigerating machine oil 103 that has passed through the inner wall surface of the washer 181 and reached the third oil pump 161 ascends in the spiral groove 162 due to a viscous force generated by a relative rotational difference between the fixed bearing 124 and the rotating main shaft portion 122a. To do.

  Here, as described above, the third oil pump 161 forms a viscous pump that uses a viscous force generated by a relative rotational difference between the bearing 124 and the rotating main shaft portion 122a. In general, since a viscous pump uses a viscous force, a strong conveying force is generated, so that the refrigerating machine oil 103 is reliably pushed up even at a low rotation of 20 Hz, for example.

  The refrigerating machine oil 103 that has reached the third oil pump 161 lubricates the sliding surface formed by the outer peripheral surface of the main shaft portion 122a and the inner peripheral surface of the bearing 124, and is further sent to the eccentric shaft portion 122b.

  Since the first gap 131 formed between the lower end surface of the bearing 124 and the upper end surface of the rotor 113 is provided with a washer 181 that can be elastically deformed in the axial direction, the first gap From 131, the refrigerating machine oil 103 hardly flows out.

  Therefore, according to the present embodiment, the refrigerating machine oil 103 can be reliably fed into each sliding portion even at a low rotation operation, and a hermetic compressor having high reliability can be realized.

  Further, in the present embodiment, the parts newly required for forming the oil pump are only the stirring plate 143 and the end plate 144 that can be formed at low cost from a pressing material of an iron plate or the like. Further, since the spiral groove 152 constituting the second oil pump 151 and the spiral groove 162 constituting the third oil pump 161 are formed by continuous spiral grooves having the same pitch angle, the spiral groove 152 is spirally formed on the outer periphery of the main shaft portion 122a. Groove processing can be performed continuously at a constant feed rate, and mass productivity can be improved.

  In the present embodiment, the diameter of the inclined hole 142 is exemplified and described. However, it is needless to say that the same action and effect can be obtained even when the inclination angle of the hole 142 is increased.

Embodiment 4 FIG.
FIG. 7 is a longitudinal sectional view when the hermetic compressor according to the fourth embodiment of the present invention is stopped, FIG. 8 is an enlarged view of a main part when the hermetic compressor according to the same embodiment is stopped, and FIG. It is a principal part enlarged view at the time of operation | movement of the hermetic compressor in the same embodiment.

  In addition, about the same structure as Embodiment 1, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  Referring to FIGS. 7 and 8, the rotor 113 is arranged by shifting the magnetic center of the rotor 113 downward from the magnetic center of the stator 112. This shift margin is made larger than the first gap formed between the lower end surface of the bearing 124 and the upper end surface of the rotor 113.

The operation and action of the hermetic compressor configured as described above will be described below.
When the stator 112 is energized from an external power source, the rotor 113 rotates with the shaft 122. Accordingly, the eccentric movement of the eccentric shaft portion 122b causes the piston 125 to reciprocate in the compression chamber 123a via the connecting means 126 to perform a predetermined compression operation for compressing the suction gas.

Next, the operation of refueling will be described.
In the first oil pump 141, as the main shaft portion 122a rotates, the refrigerating machine oil 103 rotates in the inclined hole 142 by the stirring plate 143 immersed in the refrigerating machine oil 103, and the refrigerating machine oil 103 is caused by the centrifugal force generated here. It rises along the inner wall surface of the inclined hole 142.

  Here, the position of the through hole 153 may be within a range where the rotor 113 of the main shaft portion 122a is fitted, and the diameter of the inclined hole 142 of the first oil pump 141 that supplies oil by centrifugal force is increased. The capacity can be increased, and the first oil pump 141 only needs to raise a slight head up to the second oil pump 151. For example, the refrigerating machine oil 103 reliably reaches the through hole 153 even at a low rotation of 20 Hz.

  The refrigerating machine oil 103 that has passed through the through hole 153 from the first oil pump 141 and led to the second oil pump 151 is caused by an inertial force generated upward due to the inclination in the spiral groove 152, so that the spiral groove 152 of the second oil pump 151. Rise inside.

  The refrigerating machine oil 103 passing through the first gap 131 and reaching the third oil pump 161 rises in the spiral groove 162 due to a viscous force generated by a relative rotational difference between the fixed bearing 124 and the rotating main shaft portion 122a. To do.

  Here, as described above, the third oil pump 161 forms a viscous pump that uses a viscous force generated by a relative rotational difference between the bearing 124 and the rotating main shaft portion 122a. In general, since the viscous pump uses viscous force, it generates a strong conveying force, so that the refrigerating machine oil 103 is reliably pushed up even at a low rotation of 20 Hz, for example.

  The refrigerating machine oil 103 that has reached the third oil pump 161 lubricates the sliding surface formed by the outer peripheral surface of the main shaft portion 122a and the inner peripheral surface of the bearing 124, and is further sent to the eccentric shaft portion 122b.

  On the other hand, the rotor 113 having the magnetic center shifted downward from the magnetic center of the stator 112 is lifted upward by a magnetic attractive force during operation, as shown in FIG. It becomes almost zero over. Therefore, since the refrigerating machine oil 103 flowing out from the first gap 131 can be drastically reduced, sufficient refrigerating machine oil 103 can be supplied to each sliding portion. As a result, stable oil supply can be performed during low-speed rotation, and a highly reliable effect can be obtained.

  In the first to fourth embodiments, the reciprocating compression mechanism has been described as an example, but it goes without saying that similar actions and effects can be obtained even in a scroll type or rotary type compression mechanism.

  These actions and effects are universal regardless of the type of refrigerant or refrigerating machine oil.

Embodiment 5. FIG.
FIG. 10 is a longitudinal sectional view of the hermetic compressor according to the fifth embodiment of the present invention, and FIG. 11 is a sectional view of the rotor taken along line AA in FIG. 10, showing the rotor. FIG. 12 is a cross-sectional view of the rotor assuming that the main shaft portion has an oil supply passage.

  Referring to FIGS. 10 and 11, the refrigerating machine oil 202 is stored in the sealed container 201, and the electric element 203 and the compression element 205 driven by the electric element 203 are accommodated. The compression element 205 includes the eccentric shaft portion 206 and the main shaft. A shaft 210 having a portion 207 and a main bearing 211 that supports the main shaft portion 207 are provided.

  The cylinder block 212 has a substantially cylindrical compression chamber 213 and a main bearing 211 is fixed. The piston 214 is inserted into the compression chamber 213 of the cylinder block 212 so as to be slidable in a reciprocating manner, and is connected to the eccentric shaft portion 206 by a connecting means 215.

  The first oil pump 218 includes a hollow oil cone 219 that is immersed in the refrigerator oil 202 and fixed to the lower end portion of the main shaft portion 207, and an oil supply hole 220 that is provided hollow below the shaft 210, and is a centrifugal pump. Is forming.

  The second oil pump 224 is provided above the first oil pump 218, and is composed of a spiral groove 225 provided on the outer periphery of the main shaft portion 207 and an inner wall surface of the rotor 226, and forms an inertia pump. The upper part of the first oil pump 218 and the lower part of the second oil pump 224 communicate with each other through a through hole 227.

  The third oil pump 228 is provided above the second oil pump 224 and includes a spiral groove 225 provided on the outer periphery of the main shaft portion 207 and an inner peripheral surface of the main bearing 211 to form a viscous pump.

  The electric element 203 is a two-pole self-starting permanent magnet type synchronous motor including a stator 231 and a rotor 226, and a rotor 226 in which a permanent magnet 234 is built in a rotor core 232. Further, a protective end plate 235 that prevents the permanent magnet 234 from falling off is fixed to the rotor core 232.

  The two-pole permanent magnet type motor is a self-starting permanent magnet type synchronous motor. That is, a large number of conductor bars 241 provided on the rotor core 232 and short-circuit rings 242 positioned at both ends in the axial direction of the rotor core 232 are integrally molded by aluminum die casting to form a starting cage conductor. The rotor 226 is formed with a plurality of permanent magnets 234 embedded therein.

  The permanent magnet 234 is made of a neodymium / iron / boron ferromagnetic material, which is a flat-plate rare earth magnet. As shown in FIG. 11, the permanent magnet 234 having the same polarity is inserted and arranged so as to abut in a mountain shape and rotated. The core 232 is embedded in the axial direction. The two permanent magnets 234 form a one-pole rotor magnetic pole, and the entire rotor 226 forms a two-pole rotor magnetic pole. Further, a barrier 243 for preventing a magnet short circuit is formed to prevent a magnetic flux short circuit between adjacent permanent magnets 234, and an aluminum die casting is filled in the barrier 243 hole.

  The refrigerant used in this compressor is a hydrocarbon refrigerant or the like, which is a natural refrigerant with a low warming coefficient represented by R134a and R600a having an ozone depletion coefficient of zero. Combined.

The operation and action of the hermetic compressor configured as described above will be described below with reference to FIGS.
The rotor 226 of the electric element 203 rotates the shaft 210 and the rotational movement of the eccentric shaft portion 206 is transmitted to the piston 214 via the connecting means 215, so that the piston 214 reciprocates in the compression chamber 213. Thereby, the refrigerant gas is sucked and compressed into the compression chamber 213 from a cooling system (not shown), and then discharged to the cooling system again.

Next, the operation of refueling will be described.
In the first oil pump 218, the refrigerating machine oil 202 rotates in the oil cone 219 immersed in the refrigerating machine oil 202 as the main shaft portion 207 rotates, and the refrigerating machine oil is supplied to the oil cone 219 and the oil supply by the centrifugal force generated here. It rises along the inner wall surface of the hole 220. Here, by setting the position of the through hole 227 as low as possible within the range in which the rotor 226 of the main shaft portion 207 is fitted, the volume of the oil supply hole 220 that is hollow in the main shaft portion 207 can be reduced. The effect which increases the magnetic flux amount mentioned later can be heightened.

  The refrigerating machine oil 202 that has passed through the through hole 227 from the first oil pump 218 and led to the second oil pump 224 is caused by an inertial force that is generated upward due to the inclination in the spiral groove 225, and thus the spiral groove 225 of the second oil pump 224. Rise inside.

  The refrigerating machine oil 202 that has reached the third oil pump 228 rises in the spiral groove 225 by a viscous force generated by a relative rotational difference between the fixed main bearing 211 and the rotating main shaft portion 207. The refrigerating machine oil 202 reaching the third oil pump 228 lubricates the sliding surface formed by the outer peripheral surface of the main shaft portion 207 and the inner peripheral surface of the main bearing 211 and is further sent to the eccentric shaft portion 206.

  Therefore, since the volume of the hollow portion of the main shaft portion 207 can be significantly reduced as compared with the conventional case, the refrigerating machine oil 202 is reliably supplied upward with a configuration in which a magnetic path in the main shaft portion 207 is easily formed. it can.

Next, the flow of magnetic flux of the permanent magnet will be conceptually described with reference to FIG. 11 and FIG.
As shown in FIG. 11, the flow of magnetic flux in the AA cross section of the rotor core 232 is such that the magnetic flux emitted from the upper two permanent magnets 234 passes through the center of the rotor core 232 and the lower two in the figure. Are sucked into the permanent magnet 234. On the other hand, as shown in FIG. 12, the flow of magnetic flux in the rotor core assuming the case where there is an oil supply passage that becomes a large hollow portion in the main shaft portion as in the prior art is as follows. Since it does not pass through the hollow oil supply passage and goes around the outer periphery of the hollow portion, the magnetic path of this portion tends to be narrow and insufficient.

  However, in this embodiment, since there is no hollow portion in the main shaft portion 207 as shown in FIG. 11, a magnetic path can be widely formed inside the main shaft portion 207, so the amount of magnetic flux inside the rotor core 232 increases. And loss is reduced.

  Further, since the permanent magnet 234 is formed of a rare earth magnet, and the rare earth magnet can obtain a strong magnetic force, the motor can be reduced in size and weight, and the hermetic compressor can be reduced in size and weight.

  Therefore, even when a two-pole permanent magnet type electric motor is applied to the hermetic compressor with the compression element 205 disposed at the top, the amount of magnetic flux generated by the permanent magnet can be increased, and the size, weight, and efficiency can be increased. .

Embodiment 6 FIG.
FIG. 13 is a longitudinal sectional view of a hermetic compressor according to the sixth embodiment of the present invention. 14 is a cross-sectional view of the rotor taken along line BB in FIG.

  Referring to FIGS. 13 and 14, refrigerating machine oil 302 is stored in an airtight container 301, and an electric element 303 and a compression element 305 driven by the electric element 303 are accommodated. The compression element 305 includes a shaft 309 having an eccentric shaft portion 306, a main shaft portion 307, and a subshaft portion 308, and the subshaft portion 308 is provided coaxially with the main shaft portion 307 with the eccentric shaft portion 306 interposed therebetween. The main shaft portion 307 is supported by a main bearing 310, and the sub shaft portion 308 is supported by a sub bearing 311.

  The main bearing 310 includes an end portion of the rotor core 312 on the compression element 305 side and does not intersect with a virtual plane substantially orthogonal to the main shaft portion 307 axis. That is, the axial length of the main bearing 310 is slightly shortened so that the main bearing 310 does not enter the rotor core 312, and a hollow portion is provided at the end of the rotor core 312 on the compression element 305 side. Not.

  The cylinder block 313 has a sub-bearing 311 and a substantially cylindrical compression chamber 314, and a main bearing 310 is fixed thereto. The piston 315 is inserted into the compression chamber 314 of the cylinder block 313 so as to be slidable back and forth, and is connected to the eccentric shaft portion 306 by a connecting means 316.

  The first oil pump 318 is composed of a hollow oil cone 319 that is immersed in the refrigerating machine oil 302 and fixed to the lower end portion of the main shaft portion 307, and an oil supply hole 320 that is provided hollow in the lower portion of the shaft 309. Is forming.

  The second oil pump 324 is provided above the first oil pump 318 and is composed of a spiral groove 325 provided on the outer periphery of the main shaft portion 307 and an inner wall surface of the rotor 326 to form an inertia pump. The upper part of the first oil pump 318 and the lower part of the second oil pump 324 communicate with each other through a through hole 327.

  The third oil pump 328 is provided above the second oil pump 324 and includes a spiral groove 325 provided on the outer periphery of the main shaft portion 307 and an inner peripheral surface of the main bearing 310 to form a viscous pump.

  The electric element 303 is a two-pole self-starting permanent magnet type synchronous motor including a stator 331 and a rotor 326, and a rotor 326 in which a permanent magnet 334 is built in a rotor core 312. Further, a protective end plate 335 for preventing the permanent magnet 334 from falling off is fixed to the rotor core 312.

  The two-pole permanent magnet type motor is a self-starting permanent magnet type synchronous motor. That is, a plurality of conductor bars 341 provided on the rotor core 312 and short-circuit rings 342 located at both ends in the axial direction of the rotor core 312 are integrally molded by aluminum die casting to form a starting cage conductor. The rotor 326 is formed with a plurality of permanent magnets 334 embedded therein.

  The permanent magnet 334 is made of a neodymium / iron / boron ferromagnetic material which is a flat-plate rare earth magnet. As shown in FIG. 14, the permanent magnet 334 having the same polarity is inserted and arranged so as to abut in a mountain shape and rotated. It is buried in the axial direction of the core iron core 312. The two permanent magnets 334 form a one-pole rotor magnetic pole, and the entire rotor 326 forms a two-pole rotor magnetic pole. Further, in order to prevent a magnetic flux short circuit between adjacent permanent magnets 334, a barrier 343 for preventing a magnet short circuit is formed, and the barrier 343 is configured by filling a hole with aluminum die casting.

  The refrigerant used in this compressor is a hydrocarbon refrigerant or the like, which is a natural refrigerant having a low global warming coefficient represented by R134a or R600a having an ozone depletion coefficient of zero. Combined.

The operation of the hermetic compressor configured as described above will be described below with reference to FIGS. 13 and 14.
The rotor 326 of the electric element 303 rotates the shaft 309, and the rotational movement of the eccentric shaft portion 306 is transmitted to the piston 315 via the connecting means 316, so that the piston 315 reciprocates in the compression chamber 314. As a result, the refrigerant gas is sucked and compressed into the compression chamber 314 from a cooling system (not shown), and then discharged again to the cooling system.

Next, the operation of refueling will be described.
In the first oil pump 318, the refrigerating machine oil 302 rotates in the oil cone 319 immersed in the refrigerating machine oil 302 as the main shaft portion 307 rotates, and the refrigerating machine oil is supplied to the oil cone 319 and the oil supply by the centrifugal force generated here. It rises along the inner wall surface of the hole 320. Here, by setting the position of the through hole 327 as low as possible within the range where the rotor 326 of the main shaft portion 307 is fitted, the volume of the oil supply hole 320 that is hollow in the main shaft portion 307 can be reduced. The effect which increases the magnetic flux amount mentioned later can be heightened.

  The refrigerating machine oil 302 that has passed through the through hole 327 from the first oil pump 318 and led to the second oil pump 324 is caused by an inertial force generated upward due to the inclination in the spiral groove 325, so that the spiral groove 325 of the second oil pump 324 is formed. Rise inside.

  The refrigerating machine oil 302 that has reached the third oil pump 328 rises in the spiral groove 325 by a viscous force generated by a relative rotational difference between the fixed main bearing 310 and the rotating main shaft portion 307. The refrigerating machine oil 302 that has reached the third oil pump 328 lubricates the sliding surface formed by the outer peripheral surface of the main shaft portion 307 and the inner peripheral surface of the main bearing 310, and further moves to the eccentric shaft portion 306 and the sub shaft portion 308. Sent.

  Accordingly, since the volume of the hollow portion of the main shaft portion 307 can be significantly reduced as compared with the conventional case, the refrigerating machine oil 302 is reliably supplied upward with a configuration in which a magnetic path in the main shaft portion 307 is easily formed. it can.

  Next, the flow of magnetic flux of the permanent magnet will be conceptually described with reference to FIG. As shown in FIG. 14, the flow of magnetic flux in the BB cross section of the rotor core 312 is such that the magnetic flux emitted from the upper two permanent magnets 334 passes through the center of the rotor core 312 and the lower two in the figure. Are sucked into the permanent magnet 334.

  On the other hand, as shown in FIG. 12, the flow of magnetic flux in the rotor core assuming the case where there is an oil supply passage that becomes a large hollow portion in the main shaft portion as in the prior art is as follows. Since it does not pass through the hollow oil supply passage and goes around the outer periphery of the hollow portion, the magnetic path of this portion tends to be narrow and insufficient. However, in the present embodiment, as shown in FIG. 14, since there is no hollow portion in the main shaft portion 307, a magnetic path can be formed widely in the main shaft portion 307, so that the amount of magnetic flux inside the rotor core 312 increases. , Loss is reduced.

  Further, the main bearing 310 includes the end of the rotor core 312 on the compression element 305 side and does not intersect with a virtual plane substantially orthogonal to the main shaft portion 307. Therefore, the main bearing 310 is placed in the rotor core 312. There is no hollow bore part conventionally provided for insertion. As a result, the narrowing of the magnetic path due to the hollow bore is eliminated, so that the amount of magnetic flux inside the rotor core 312 is further increased and the efficiency is further improved.

  The shaft 309 further includes an eccentric shaft portion 306, a main shaft portion 307, and a subshaft portion 308. The subshaft portion 308 is provided coaxially with the main shaft portion 307 with the eccentric shaft portion 306 interposed therebetween, and the main shaft portion 307. Is supported by the main bearing 310, and the auxiliary shaft portion 308 is supported by the auxiliary bearing 311.

  Therefore, in order to fundamentally regulate the inclination of the shaft 309, even if the length of the main bearing 310 is shortened and the main bearing 310 is not inserted into the rotor core 312, the inclination of the shaft 309 is extremely small. Since the shaft 309, the main bearing 310, and the sub bearing 311 are hardly twisted, reliability and efficiency can be increased and noise can be reduced.

  Further, since the permanent magnet 334 is formed of a rare earth magnet and the rare earth magnet can obtain a strong magnetic force, the motor can be reduced in size and weight and the hermetic compressor can be reduced in size and weight.

  Therefore, even when a two-pole permanent magnet type electric motor is applied to a hermetic compressor with the compression element 305 disposed on the upper side, the amount of magnetic flux generated by the permanent magnet is increased, so that it is small and lightweight, high efficiency, low noise, high Can be reliable.

  The hermetic compressor according to the present invention can perform stable oil supply during low-speed rotation, increase the amount of magnetic flux inside the rotor core, reduce loss, and reduce the size, weight, and efficiency. Therefore, it is useful as a hermetic compressor for refrigeration and refrigerating apparatuses such as household electric refrigerators, dehumidifiers, showcases, vending machines, and air conditioners.

It is a longitudinal cross-sectional view of the hermetic compressor in Embodiment 1 of this invention. FIG. 2 is an enlarged view of a main part of the hermetic compressor in the first embodiment. It is a longitudinal cross-sectional view of the hermetic compressor in Embodiment 2 of this invention. FIG. 4 is an enlarged view of a main part of a hermetic compressor in a second embodiment. It is a longitudinal cross-sectional view of the hermetic compressor in Embodiment 3 of this invention. FIG. 5 is an enlarged view of a main part of a hermetic compressor in a third embodiment. It is a longitudinal cross-sectional view at the time of a stop of the hermetic compressor in Embodiment 4 of the present invention. FIG. 10 is an enlarged view of a main part when a hermetic compressor according to a fourth embodiment is stopped. FIG. 10 is an enlarged view of a main part during operation of a hermetic compressor in a fourth embodiment. It is a longitudinal cross-sectional view of the hermetic compressor in Embodiment 5 of this invention. FIG. 10 is a cross-sectional view of a rotor in a fifth embodiment. It is sectional drawing of a rotor in case a oil supply path exists in a main-shaft part. It is a longitudinal cross-sectional view of the hermetic compressor in Embodiment 6 of this invention. FIG. 10 is a cross-sectional view of a rotor in a sixth embodiment. It is a longitudinal cross-sectional view of the conventional hermetic compressor. It is a principal part enlarged view of the hermetic compressor of FIG. It is a longitudinal cross-sectional view of another conventional hermetic compressor. It is a longitudinal cross-sectional view of another conventional hermetic compressor.

Claims (14)

A refrigerant and refrigerating machine oil are enclosed in a sealed container, and an electric element composed of a rotor and a stator is accommodated in the sealed container, and a compression element driven by the electric element is accommodated in an upper part of the sealed container, The compression element includes a shaft disposed in a vertical direction and fitted with the rotor, and a bearing that supports the shaft, and is provided at a lower portion of the shaft and opens into the refrigerating machine oil. And a second oil pump provided above the first oil pump, formed by a spiral groove provided on the outer periphery of the shaft and an inner wall surface of the rotor, and provided above the second oil pump, A hermetic compressor including a third oil pump formed by a spiral groove provided on the outer periphery of the shaft and an inner peripheral surface of the bearing. The hermetic compressor according to claim 1, wherein the spiral groove of the second oil pump and the spiral groove of the third oil pump are formed continuously. The hermetic compressor according to claim 2, wherein the spiral groove of the second oil pump and the spiral groove of the third oil pump are opened in a first gap formed between the rotor and the bearing. The hermetic compressor according to claim 3, wherein the first gap is 0.5 mm or less over the entire circumference. The hermetic mold according to claim 2, wherein a bore portion from which a bearing extends is provided on a rotor upper end surface side, and a second gap is formed between an inner peripheral surface of the bore portion and an outer peripheral surface of the bearing. Compressor. The hermetic compressor according to claim 5, wherein the second gap is 1.0 mm or less over the entire circumference. The hermetic compressor according to claim 5 or 6, wherein a depth of the bore portion is 5.0 mm or more. The hermetic compressor according to claim 3, wherein a washer capable of being elastically deformed in the axial direction is interposed in the first gap. 4. The magnetic center of the rotor is arranged to be shifted downward from the magnetic center of the stator, and the first gap is almost zero over the entire circumference by raising the rotor by a magnetic attractive force during operation. The hermetic compressor described in 1. Refrigerating machine oil is stored in a sealed container, and an electric element composed of a rotor and a stator and a compression element driven by the electric element are accommodated in the sealed container. The compression element has an eccentric shaft portion and a main shaft portion. A shaft having a shaft, a main bearing that pivotally supports the main shaft portion, a first oil pump that is provided at a lower portion of the shaft and that opens into the refrigerating machine oil, and is provided above the first oil pump. A second oil pump formed by a spiral groove provided on the inner surface of the rotor and an inner wall surface of the rotor, and a spiral groove provided on the outer periphery of the shaft and an inner periphery of the main bearing. A hermetic compressor that is a two-pole permanent magnet type motor in which a permanent magnet is built in the rotor core of the rotor. The hermetic compressor according to claim 10, wherein the main bearing includes a compression element side end of a rotor core and does not intersect a plane substantially orthogonal to the main shaft axis. The hermetic compressor according to claim 10 or 11, further comprising: a sub-shaft portion provided coaxially with the main shaft portion with the eccentric shaft portion interposed therebetween; and a sub-bearing that pivotally supports the sub-shaft portion. The two-pole permanent magnet type electric motor has a plurality of conductor bars of a squirrel-cage conductor on the outer periphery of a rotor core, and a self-starter provided with a rotor having a plurality of permanent magnets embedded therein The hermetic compressor according to any one of claims 10 to 12, wherein the hermetic compressor is a permanent magnet synchronous motor. The hermetic compressor according to any one of claims 10 to 13, wherein the permanent magnet is formed of a rare earth magnet.

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