JP2009191763A - Hermetic compressor - Google Patents

Abstract

An object of the present invention is to provide a hermetic compressor that can ensure high reliability by supplying oil to each sliding portion even during reverse rotation.
A bearing portion that supports a main shaft portion 111, a crankshaft 113 includes an oil supply mechanism 121 that conveys oil upward, and the oil supply mechanism 121 includes a centrifugal pump 122 that opens into the oil, and a main shaft portion 111. A spiral groove 123 engraved between the bearing portion, one end communicating with the centrifugal pump 122, the other end communicating with the upper portion of the main shaft portion 111, one end opening at the upper portion of the centrifugal pump 122, and the other end of the main shaft An oil supply hole 126 that opens to the top of the portion 111 and that is formed independently of the spiral groove 123 is provided, and the oil is fed from the centrifugal pump 122 through the oil supply hole 126 even during reverse rotation. By being guided to the upper part of 111 and lubricating the sliding part of the main shaft part 111, the sliding part can be prevented from being worn or damaged, and a highly reliable hermetic compressor can be provided.
[Selection] Figure 3

Description

  The present invention relates to an oil supply mechanism for a hermetic compressor.

  Conventionally, an oil supply device for a general hermetic compressor includes an oil supply mechanism that pumps up oil stored in a closed container, and a spiral that supplies centrifugal force generated by rotation of a rotary shaft to each sliding portion. The crankshaft is provided with a shape oil groove, and the oil pumped up by the oil supply mechanism lubricates the main shaft while passing through the spiral oil groove, and further lubricates each sliding part such as the eccentric part. (For example, refer to Patent Document 1).

  The prior art hermetic compressor will be described below with reference to the drawings.

  FIG. 5 is a longitudinal sectional view of a conventional hermetic compressor described in Patent Document 1, and FIG. 6 is an electrical wiring diagram of the conventional hermetic compressor.

  In FIG. 5, an electric motor 4 including a stator 18 and a rotor 8 and a compression mechanism portion 2 are disposed in the hermetic container 1. The crankshaft 7 is pivotally supported in the bearing portion 6 of the block 3 constituting the compression mechanism portion 2, and the rotor 8 is fixed to the outer diameter portion of the crankshaft 7, and the slider 11 of the piston 10 via the eccentric shaft 9. Is engaged.

  A centrifugal pump 12 is formed in the crankshaft 7 and opens to the oil 17 at the lower end.

  A portion of the crankshaft 7 located in the bearing portion 6 is provided with a spiral groove 14 having a lead in a direction in which the oil 17 is guided upward when the crankshaft 7 rotates forward.

  The spiral groove 14 has a lower end communicating with the centrifugal pump 12 via the communication hole 13, and an upper end having an annular oil groove formed by a gap between the chamfer 22 provided at the upper end of the bearing portion 6 of the block 3 and the crankshaft 7. 16 is communicated.

  The vertical hole 15 provided in the eccentric shaft 9 has a lower end communicating with the annular oil groove 16 and an upper end opening in the inner space of the sealed container 1.

  Further, as shown in FIG. 6, a main coil 19 and a starting coil 20 are connected in parallel to the stator 18, and a PTC relay 21 is wired in series with the starting coil 20 as a starting device, so that a single-phase resistance starting type is provided. The induction motor is formed.

  The operation of the conventional hermetic compressor configured as described above will be described below.

  When the stator 18 is energized, a starting torque is generated in the positive rotation direction with the element resistance of the PTC relay 21 wired in series with the starting coil 20 of the stator 18, and the rotor 8 starts rotating.

  Thereafter, the element of the PTC relay 21 suddenly increases its resistance by self-heating due to current, and the starting coil 20 is substantially cut off, so that the rotor 8 is rotationally driven only by the main coil 19, and accordingly the crankshaft 7. Rotates, and the piston 10 engaged through the eccentric shaft 9 and the slider 11 reciprocates, whereby a known compression operation is performed.

  At this time, the oil 17 is raised by the centrifugal force acting in the centrifugal pump 12 from the lower end of the crankshaft 7 and supplied from the communication hole 13 to the spiral groove 14, and the upward conveying force is urged by the spiral groove 14. The

At this time, the oil 17 forms an oil film on the sliding surfaces of the bearing portion 6 and the crankshaft 7 to suppress metal contact and prevent wear. Then, the oil 17 conveyed further upward is supplied to the annular oil groove 16, and part of the oil 17 is discharged into the space in the sealed container 1 through the vertical hole 15, and part of the oil 17 is compressed into the compression mechanism unit 2. And an oil film is formed on each sliding portion of the compression mechanism portion 2 to suppress metal contact and prevent wear.
Japanese Patent Publication No.62-44108

  However, in the above-described conventional configuration, in order to resume normal operation after the operation is stopped, it is necessary to energize the starting coil 20, and for this purpose, a predetermined element for reducing the resistance of the element of the PTC relay 21 is required. Cooling time is required.

  Therefore, when the cooling time is extremely short (for example, an instantaneous power failure), the element of the PTC relay 21 remains high in resistance, so that the start coil 20 is not energized and normally does not start. However, when the repulsive force of the compressed gas compressed and boosted by the reciprocating motion of the piston 10 is applied to the piston 10 as an external force in the reverse rotation direction, this becomes a starting torque in the reverse rotation direction, and the reverse rotation operation is started.

  Then, the lead direction is set on the assumption that the spiral groove 14 operates in the forward rotation direction. Therefore, when the crankshaft 7 rotates in the reverse direction, a downward force acts on the oil 17 in the spiral groove 14 and the bearing portion. The oil 17 is not supplied upward from 6.

  This reverse rotation continues until the hermetic compressor next stops, and normally returns to the normal rotation in the subsequent operation. However, along with the occurrence of this reverse rotation, oil supply hindrance occurs in the crankshaft 7, wear occurs in each sliding portion and main shaft portion of the compression mechanism portion 2, and the reliability of the hermetic compressor is greatly reduced. Had a problem.

  An object of the present invention is to solve the above-described conventional problems, and to provide a hermetic compressor having sufficient reliability by supplying sufficient oil to each sliding portion even when the crankshaft rotates in the reverse direction. And

  In order to solve the above-described conventional problems, an oil supply mechanism provided on the crankshaft is engraved between a centrifugal pump that opens in the oil, a main shaft portion and a bearing portion, and one end communicates with the centrifugal pump. A spiral groove whose end communicates with the upper portion of the main shaft portion, an oil supply hole that opens at one end of the centrifugal pump, opens at the other end at the upper portion of the main shaft portion, and is formed independently of the spiral groove. Even when the crankshaft rotates in the reverse direction, the oil is guided from the centrifugal pump to the upper portion of the main shaft portion through the oil supply hole, and has an action of lubricating the sliding portion of the main shaft portion.

  The hermetic compressor of the present invention can provide sufficient lubrication to each sliding portion even when the crankshaft rotates in reverse, and therefore provides a hermetic compressor with high reliability. Can do.

  The invention according to claim 1 of the present invention includes a single-phase induction type electric motor composed of a stator and a rotor, a compression mechanism portion driven by the electric motor, the electric motor, and the compression mechanism portion. An airtight container for storing oil, and the compression mechanism portion includes a crankshaft having a main shaft portion and an eccentric shaft portion, a cylinder forming a compression chamber, and a bearing portion that supports the main shaft portion. The crankshaft includes an oil supply mechanism that conveys the oil upward, and the oil supply mechanism is engraved between the centrifugal pump that opens into the oil, the main shaft portion, and the bearing portion. A spiral groove having one end communicating with the centrifugal pump and the other end communicating with the upper portion of the main shaft portion, one end opening at the upper portion of the centrifugal pump, the other end opening at the upper portion of the main shaft portion, and the What is a spiral groove? Even when the crankshaft rotates in the reverse direction, the oil is guided from the centrifugal pump to the upper part of the main shaft part through the oil supply hole, and the main shaft part etc. Since the oil is sufficiently supplied to the sliding parts and lubricated, an oil film is formed on each sliding part to suppress metal contact, preventing wear and scratches on each sliding part, and a highly reliable hermetic compressor Can be provided.

  According to a second aspect of the present invention, in the first aspect of the present invention, an annular oil groove is provided at an upper portion of the main shaft portion, an upper end of the spiral groove communicates with the annular oil groove, and an oil supply hole is directly or indirectly provided. Even when the crankshaft rotates in the reverse direction, the oil is guided from the centrifugal pump to the annular oil groove at the top of the main shaft portion through the oil supply hole, and the oil accumulates in the annular groove. In addition to the effect of the invention according to claim 1, in addition to the effect of the invention of claim 1, it is possible to sufficiently supply the entire upper part of the main shaft part, and at the time of restart after stopping The oil stored in the annular groove is quickly supplied to the sliding portion, so that insufficient oil supply can be suppressed.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the oil supply hole opens to the upper portion of the main shaft portion via a horizontal hole, and the horizontal hole does not directly communicate with the spiral groove. The oil discharged from the oil supply hole to the sliding part of the crankshaft and the bearing part can be prevented from flowing directly into the spiral groove when the oil is reversely rotated. In addition to the effect of the present invention, a sufficient amount of oil to be guided to each sliding portion such as the eccentric shaft portion above the main shaft portion can be secured.

  The invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein the oil supply hole is opened to the centrifugal pump in the vicinity of the axial center of the main shaft portion. The oil flowing into the oil supply hole is suppressed and led mainly to the spiral groove, and at the time of reverse rotation, the centrifugal pump is filled with oil, flows into the oil supply hole, and is supplied to the upper sliding portion. In addition to the effect of the invention described in any one of items 1 to 3, it is possible to stably and sufficiently supply oil to each sliding portion such as the main shaft portion at the time of forward rotation and reverse rotation.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the oil supply hole is inclined outward from the lower side to the upper side. In addition to the effect of the invention according to any one of claims 1 to 4, in addition to the effect of the invention according to any one of claims 1 to 4, the oil supply hole can be pumped through the oil supply hole during reverse rotation. In addition, a large amount of oil can be supplied to each sliding portion such as the main shaft portion further above.

  The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein the position of the spiral groove communicating with the centrifugal pump is lower than the opening of the oil supply hole that opens to the centrifugal pump. Since the oil in the centrifugal pump flows into the spiral groove before flowing into the oil supply hole when the crankshaft rotates normally, the effect of the invention according to any one of claims 1 to 5 is achieved. In addition, during the forward rotation of the crankshaft, it is possible to suppress oil supply obstruction by the oil supply hole and supply a large amount of oil to each sliding portion such as the upper main shaft portion.

  The invention according to claim 7 is the invention according to any one of claims 1 to 6, wherein one end is communicated with the annular oil groove and the other end is opened in the sealed container. When the crankshaft rotates in the forward direction, oil is conveyed to the eccentric shaft through the annular oil groove and the vertical hole, and when the crankshaft rotates in the reverse direction, it is pumped up to the upper part of the main shaft through the oiling hole. In addition to the effect of the invention according to any one of claims 1 to 6, in addition to the effect of the invention according to any one of claims 1 to 6, further forward rotation and reverse rotation are achieved. At times, sufficient lubrication can be performed stably at each sliding portion such as the eccentric shaft portion.

  Hereinafter, embodiments of a hermetic compressor according to the present invention will be described with reference to the drawings. In addition, this invention is not limited by this embodiment.

(Embodiment 1)
1 is a longitudinal sectional view of a hermetic compressor according to Embodiment 1 of the present invention, FIG. 2 is a front view of a crankshaft in the hermetic compressor of the same embodiment, and FIG. 3 is taken along line AA in FIG. FIG. 4 is an electrical wiring diagram of the hermetic compressor according to the embodiment.

  The operation of the compressor configured as described above will be described below.

  1 to 3, a single-phase induction type electric motor 103 including a stator 101 and a rotor 102, a compression mechanism unit 106 driven by the electric motor 103, an electric motor 103, and a compression mechanism in a sealed container 108. The part 106 is accommodated and the oil 107 is stored.

  The compression mechanism section 106 includes a crankshaft 113 having a main shaft section 111 and an eccentric shaft section 112, a cylinder 117 that forms a compression chamber 116, and a bearing section 118 that supports the main shaft section 111. Includes an oil supply mechanism 121 that conveys the oil 107 upward.

  A piston 119 is inserted into the cylinder 117 so as to be reciprocally movable, and the eccentric shaft portion 112 and the piston 119 are connected by a connecting rod 120 serving as a connecting means.

  The oil supply mechanism 121 includes a centrifugal pump 122 that opens into the oil 107, is engraved between the main shaft portion 111 and the bearing portion 118, one end communicates with the centrifugal pump 122, and the other end is the main shaft portion 111. A helical groove 123 that communicates with the upper portion of the gas pump, and an oil supply hole 126 that has one end opened at the upper portion of the centrifugal pump 122, the other end opened at the upper portion of the main shaft portion 111, and is formed independently of the helical groove 123. I have.

  An end portion 126 a of the oil supply hole 126 opens to the centrifugal pump 122 in the vicinity of the shaft center of the main shaft portion 111, and inclines from the lower side to the upper side, that is, the sliding surface side of the main shaft portion, and the other end passes through the horizontal hole 128. It opens to the upper part of the main shaft part 111, and the lateral hole 128 is not in direct communication with the spiral groove 123.

  The annular oil groove 127 is provided at the upper part of the main shaft portion 111 and communicates with the upper end of the spiral groove 123 and also directly or indirectly communicates with the oil supply hole 126.

  Further, the position of the lateral hole 140 of the spiral groove 123 communicating with the centrifugal pump 122 is formed below the end portion 126 a of the oil supply hole 126 that opens to the centrifugal pump 122.

  Further, the vertical hole 131 is formed in the eccentric shaft portion 112, one end communicates with the annular oil groove 127, and the other end opens into the sealed container 108 at the upper end surface 112 a of the eccentric shaft portion 112.

  In FIG. 4, a main coil 141 and a starting coil 142 are connected in parallel to the stator 101, and a PTC relay 143 is wired in series with the starting coil 142 as a starting device.

  The operation and action of the hermetic compressor configured as described above will be described below.

  When the stator 101 is energized, a starting torque is generated in a predetermined forward rotation with the element resistance of the PTC relay 143 wired in series with the starting coil 142 of the stator 101, and the operation is started.

  Thereafter, the energization of the starting coil 142 is interrupted by the sudden increase in resistance of the elements of the PTC relay 143, and the rotor 102 rotates forward by energizing only the main coil 141.

  As the rotor 102 rotates, the crankshaft 113 rotates, and the eccentric movement of the eccentric shaft portion 112 causes the piston 119 to reciprocate in the cylinder 117 via the connecting rod 120, so that a known compression operation is performed.

  Next, the supply of the oil 107 when the crankshaft 113 is operated in the forward rotation direction will be described.

  The oil 107 in the hermetic container 108 rises in the centrifugal pump 122 due to the centrifugal force generated in the centrifugal pump 122 by the rotation of the crankshaft 113 and is collected on the outer peripheral portion away from the shaft core in the centrifugal pump 122.

  Further, the position of the spiral groove 123 communicating with the centrifugal pump 122, that is, the position of the lateral hole 140 is below the end 126 a of the oil supply hole 126 opening to the centrifugal pump 122, which is on the centrifugal pump 122 side. Most of the oil 107 is conveyed to the spiral groove 123 before flowing into the oil supply hole 126.

  Thereafter, the oil 107 conveyed to the spiral groove 123 is guided to the annular oil groove 127 by the pumping ability of the spiral groove 123, and the oil 107 is collected in the annular oil groove 127 and supplied to the entire upper periphery of the main shaft portion 111. In addition, when restarting after stopping, the oil 107 stored in the annular oil groove 127 is promptly supplied to the sliding portion between the main shaft portion 111 and the bearing portion 118 and the shortage of oil supply can be suppressed.

  Further, the oil 107 introduced into the annular oil groove 127 is collected by the centrifugal force on the outer periphery of the annular oil groove 127, and the lateral hole 128 is not directly connected to the spiral groove 123. While the guided oil 107 does not flow into the lateral hole 128 of the oil supply hole 126, while further ensuring a sufficient amount of oil 107 to be guided to each sliding portion such as the eccentric shaft portion 112 above the main shaft portion 111, Guided to the lower end of the vertical hole 131 communicating with the annular oil groove 127.

  A part of the oil 107 guided to the vertical hole 131 is supplied to the connecting rod 120 and the piston 119 to lubricate the sliding portion, and the remaining oil 107 is discharged from the upper end into the space in the sealed container 108.

  As described above, during forward rotation of the crankshaft 113, it is possible to suppress oil supply obstruction by the oil supply hole 126 and supply sufficient oil 107 to each sliding portion such as the upper main shaft portion 111. The oil supply characteristics can be maintained.

  Next, the supply of the oil 107 when the crankshaft 113 is operated in the reverse rotation direction will be described.

  In order to temporarily stop operation and start normal operation again, it is necessary to energize the starting coil 142. For this purpose, a predetermined cooling time required for the element of the PTC relay 143 to reduce the resistance is required. become.

  Accordingly, when re-energization is performed with this cooling time being extremely short (for example, after an instantaneous power failure), the element of the PTC relay 143 remains high in resistance, so that the start coil 142 is not energized and normally does not start.

  However, the piston 119 is pushed back by the repulsive force of the compressed gas that has been compressed and boosted by the reciprocating motion of the piston 119, and when the crankshaft 113 is rotated in the reverse rotation direction, this becomes the starting torque in the reverse rotation direction, and the reverse rotation operation is performed. It will start.

  At this time, since the centrifugal pump 122 exhibits a pumping action regardless of the rotation direction, the centrifugal pump 122 is pumped up by the centrifugal pump 122 in the same manner as in the normal rotation. Thereafter, the oil 107 is collected by the centrifugal force on the outer peripheral portion away from the shaft core in the centrifugal pump 122, and the process up to this point is the same as in the normal rotation.

  Although the oil 107 is pumped up by the centrifugal pump 122 and guided to the lower end of the spiral groove 123 through the horizontal hole 140, a downward force acts on the oil 107 in the spiral groove 123. Cannot flow toward the upper part, and is stored in the centrifugal pump 122 without being conveyed anywhere.

  Therefore, the inside of the centrifugal pump 122 is filled with the oil 107, and the oil 107 is pumped up into the oil supply hole 126 formed in the upper part of the centrifugal pump 122.

  Since the oil supply hole 126 is inclined outward from the lower side to the upper side, the oil 107 that has flowed into the oil supply hole 126 is pumped up more in the oil supply hole 126 from the lower part to the upper part by the centrifugal force acting on the oil supply hole 126. To the annular oil groove 127.

  Here, the amount of the oil 107 pumped up by the oil supply hole 126 is determined by the pumping capacity of the centrifugal pump 122 and the oil supply hole 126 itself, but the pump capacity is determined by the amount of the oil 107 that can sufficiently lubricate each sliding portion. This design is designed so that at least a sufficient amount of oil can be obtained in order to ensure reliability, even if the transfer capacity is not equivalent to that during forward rotation.

  In addition, the oil 107 guided into the annular oil groove 127 is stored in the annular oil groove 127 and supplied to the entire upper periphery of the main shaft portion 111, so that sufficient oil is supplied to the entire upper portion of the main shaft portion 111. In addition, the oil 107 stored in the annular oil groove 127 can be quickly supplied to the sliding portion between the main shaft portion 111 and the bearing portion 118 at the time of restart after the stop, thereby suppressing the shortage of oil supply. .

  Further, the oil 107 stored in the annular oil groove 127 is transferred to the annular oil groove 127 while securing a sufficient amount of oil 107 to be guided to each sliding portion such as the eccentric shaft portion 112 above the main shaft portion 111. It is led to the lower end of the communicating vertical hole 131.

  A part of the oil 107 guided to the vertical hole 131 is supplied to the connecting rod 120 and the piston 119 to lubricate the sliding portion, and the remaining oil 107 is discharged from the upper end into the space in the sealed container 108.

  A part of the oil 107 in the annular oil groove 127 flows into the spiral groove 123 by its own weight not only when the compressor is stopped but also during operation, and is supplied to the main shaft portion 111.

  As described above, even when the crankshaft 113 is reversely rotated, sufficient oil 107 can be supplied to each sliding portion such as the upper main shaft portion 111 as in the case of normal rotation. Characteristics can be maintained.

  Therefore, sufficient oil 107 can be supplied to sliding parts such as the main shaft part 111 stably during both forward rotation and reverse rotation, and an oil film is formed on each sliding part to suppress metal contact and wear of the sliding parts. And a highly reliable hermetic compressor can be provided.

  In the present embodiment, the electric motor is a single-phase induction type. However, even in the case where a DC motor or the like such as an inverter compressor is mounted, the same action is achieved if the hermetic compressor generates reverse rotation. Needless to say, an effect can be obtained.

  As described above, according to the present embodiment, the amount of oil supply during forward rotation is equivalent to that of the conventional product, and a sufficient amount of oil supply can be obtained even at the time of reverse rotation to ensure at least reliability. Therefore, it is possible to realize a hermetic compressor that secures performance.

  As described above, the hermetic compressor according to the present invention can stably supply sufficient oil by an oil supply mechanism using a pressure difference. It can be applied to all uses using refrigeration cycles such as showcases and vending machines.

1 is a longitudinal sectional view of a hermetic compressor according to Embodiment 1 of the present invention. Front view of the crankshaft in the hermetic compressor of the embodiment Sectional drawing of the principal part in the AA line of FIG. Electrical wiring diagram of hermetic compressor in the same embodiment Vertical section of a conventional hermetic compressor Electric wiring diagram of conventional hermetic compressor

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Stator 102 Rotor 103 Electric motor 106 Compression mechanism part 107 Oil 108 Sealed container 111 Main shaft part 112 Eccentric shaft part 113 Crankshaft 116 Compression chamber 117 Cylinder 118 Bearing part 121 Oil supply mechanism 122 Centrifugal pump 123 Spiral groove 126 Oil supply hole 127 Annular oil Groove 128 Horizontal hole 131 Vertical hole

Claims (7)

  A single-phase induction type electric motor composed of a stator and a rotor, a compression mechanism portion driven by the electric motor, and a sealed container for storing the electric motor and the compression mechanism portion and storing oil. The compression mechanism portion includes a crankshaft having a main shaft portion and an eccentric shaft portion, a cylinder forming a compression chamber, and a bearing portion that supports the main shaft portion, and the crankshaft receives the oil. An oil supply mechanism that conveys upward; the oil supply mechanism is engraved between the centrifugal pump that opens in the oil, the main shaft portion and the bearing portion, and one end communicates with the centrifugal pump; A spiral groove communicating with the upper part of the main shaft part, an oil supply hole having one end opened at the upper part of the centrifugal pump, the other end opened at the upper part of the main shaft part, and formed independently of the spiral groove And with Hermetic compressor.   The hermetic compressor according to claim 1, wherein an annular oil groove is provided in an upper part of the main shaft portion, an upper end of the spiral groove communicates with the annular oil groove, and an oil supply hole opens directly or indirectly in the annular oil groove. .   3. The hermetic compressor according to claim 1, wherein the oil supply hole opens at an upper portion of the main shaft portion through a horizontal hole, and the horizontal hole does not directly communicate with the spiral groove.   The hermetic compressor according to any one of claims 1 to 3, wherein the oil supply hole is opened to the centrifugal pump in the vicinity of the axis of the main shaft.   The hermetic compressor according to any one of claims 1 to 4, wherein the oil supply hole is inclined outward from below to above.   The hermetic compressor according to any one of claims 1 to 5, wherein a position of a spiral groove communicating with the centrifugal pump is set lower than an opening portion of an oil supply hole opening in the centrifugal pump.   The hermetic compressor according to any one of claims 1 to 6, further comprising a vertical hole that is drilled in the eccentric shaft portion and has one end communicating with the annular oil groove and the other end opening into the sealed container.