JP2008038694A - Compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compressor with high efficiency capable of preventing increase of suction loss caused by opening delay of a suction lead valve in a suction stroke. <P>SOLUTION: The compressor includes a cylinder that stores a reciprocating piston, a valve seat plate 120 provided on an opening end of the cylinder and having a suction hole 123 bored thereon, a valve seat 121 provided on an opening end side of the cylinder of the seat valve plate 120 to surround the suction hole 123, and the suction lead valve provided between the opening end and the valve seat plate 120 so as to open and close the valve seat 121. Since the valve seat 121 is provided with auxiliary valve seats 126a, 126b and 126c on its inner peripheral portion, peripheral stress acting on the suction lead valve in a compression stroke can be reduced so that the diameter of the valve seat 121 can be increased. As a result, a differential pressure load acting on the suction lead valve due to pressure difference between a compression chamber and the suction hole 123 can be increased in the suction stroke, and suction efficiency can be increased by advancing timing of start of opening the suction lead valve. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention mainly relates to an improvement in the efficiency of a compressor used in a refrigeration apparatus such as a refrigerator.

  Conventionally, this type of compressor is provided with a diameter-expanding portion that gradually increases the diameter of a suction hole provided in a valve seat plate (see, for example, Patent Document 1).

  The conventional compressor will be described below with reference to the drawings.

  9 is a cross-sectional view of a conventional compressor, FIG. 10 is a cross-sectional view of a suction reed valve portion of a conventional compressor, FIG. 11 is a plan view of a valve seat plate of the conventional compressor, and FIG. It is an intake reed valve top view.

  9 to 12, the sealed container 1 accommodates an electric element 4 including a stator 2 and a rotor 3 and a compression element 5 driven by the electric element 4. The suction pipe 6 is fixed to the sealed container 1 and connected to the low pressure side (not shown) of the refrigeration cycle, and the discharge pipe (not shown) is fixed to the sealed container 1 and the high pressure side of the refrigeration cycle (shown). (Not shown). In addition, oil 7 is stored at the bottom of the sealed container 1.

  Next, the compression element 5 will be described.

  The crankshaft 10 includes a main shaft portion 11 in which the rotor 3 is press-fitted and fixed, and an eccentric portion 12 that is formed eccentric to the main shaft portion 11.

  The cylinder 13 includes a bearing portion 15 that forms a substantially cylindrical compression chamber 14 and supports the main shaft portion 11.

  The piston 16 is inserted into the compression chamber 14 so as to be slidable back and forth, and is connected to the eccentric portion 12 by a connecting rod 17.

  The opening end surface of the compression chamber 14 is sealed by a valve seat plate 20. The valve seat plate 20 is provided with a valve seat 21 and a suction hole 23 formed in the inner peripheral portion of the valve seat 21.

  The suction reed valve 22 is fixed between the opening end face of the compression chamber 14 and the valve seat plate 20 so that the suction hole 23 can be opened and closed.

  The cylinder head 24 forming the high pressure chamber is fixed to the opposite side of the compression chamber 14 via the valve seat plate 20.

  A suction muffler 26 made of synthetic resin and having an expansion space 25 is sandwiched and fixed between the valve seat plate 20 and the cylinder head 24 in communication with the suction hole 23.

  The suction port 26 a of the suction muffler 26 opens into the space 1 a of the sealed container 1. Here, the two-dot chain line shown in FIG. 11 is a virtual line 30 of the bore inner diameter and a virtual line 31 of the suction reed valve.

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

  When the electric element 4 is energized, the rotor 3 and the crankshaft 10 fixed to the rotor 3 rotate, and the piston 16 reciprocates in the compression chamber 14 via the connecting rod 17 by the rotational movement of the eccentric portion 12. I do.

  In the intake stroke, when the piston 16 moves toward the bottom dead center and the pressure in the compression chamber 14 falls below the pressure in the suction hole 23 of the valve seat plate 20, the suction reed valve 22 starts to open and the refrigerant gas starts to be sucked. Is done. In the compression stroke, the refrigerant gas is discharged from the compression chamber 14 after being compressed in the compression chamber 14.

  Thus, the compression action is achieved by repeating the suction, compression, and discharge strokes by the reciprocating motion of the piston 16, and the refrigerant gas flows from the low pressure side (not shown) of the refrigeration cycle to the suction pipe 6, the sealed container. 1 through a space 1a through the suction port 26a of the suction muffler 26, through the expansion space 25 and sucked from the suction hole 23 of the valve seat plate 20, and after being compressed in the compression chamber 14, a discharge pipe (not shown) is passed through. It is discharged to the high pressure side (not shown) of the refrigeration cycle connected to the sealed container 1 through.

The oil 7 stored in the bottom of the sealed container 1 lubricates the sliding portion of the compression element 5 by an oil supply mechanism (not shown), and seals the piston 16 in the compression chamber 14 and the suction reed valve. The sealing part of 22 and the valve seat 21 is sealed.
JP-A-11-241683

  However, in the above-described conventional configuration, when the suction reed valve 22 starts to open as the pressure in the compression chamber 14 decreases during the suction stroke, the suction is performed by the viscous contact force of the oil 7 sealing the suction reed valve 22 and the valve seat 21. Since the opening start of the reed valve 22 is delayed, the suction efficiency is reduced by the opening delay of the suction reed valve 22, and the condition that the viscosity of the oil 7 is high or the supply of the oil 7 to the seal portion of the valve seat 21 is performed. In the case of an excessively large number of conditions, there is a problem that the delay in opening increases due to an increase in the adhesion between the suction reed valve 22 and the valve seat 21 and the suction efficiency decreases.

  On the other hand, by increasing the diameter of the valve seat 21, the opening of the suction reed valve 22 can be started earlier, but the circumferential stress acting on the suction reed valve 22 due to the discharge pressure during the discharge stroke increases. Therefore, there is a problem that the reliability of the suction reed valve 22 and the valve seat 21 is lowered.

  The present invention solves the above-described conventional problems, and an object thereof is to provide a highly efficient compressor in which the suction loss due to the delay in opening the suction reed valve 22 is reduced.

  In order to solve the above-described conventional problems, the compressor according to the present invention includes an auxiliary valve seat on the inner peripheral portion of a valve seat provided so as to surround a suction hole formed in the valve seat plate. Because the auxiliary valve seat can reduce the deformation of the suction reed valve during the discharge pressure action and reduce the circumferential stress, the suction lead can be increased by increasing the differential pressure load acting on the suction reed valve by expanding the valve seat diameter. It has the effect of opening the valve early.

  The compressor according to the present invention can provide an efficient compressor because the opening of the suction reed valve can be started earlier.

  The invention according to claim 1 is a cylinder that houses a reciprocating piston, a valve seat plate that is disposed at an opening end of the cylinder and has a suction hole, and an opening end side of the cylinder of the valve seat plate A valve seat provided so as to surround the suction hole, and a suction reed valve provided between the opening end and the valve seat plate to open and close the valve seat, and an auxiliary valve seat is provided on an inner peripheral portion of the valve seat. With the auxiliary valve seat, the deformation of the suction reed valve during discharge pressure action can be reduced and the circumferential stress can be reduced, increasing the valve seat diameter and increasing the differential pressure load acting on the suction reed valve. This makes it possible to speed up the opening of the suction reed valve, thereby reducing the suction loss caused by the delay in opening the suction reed valve during the suction stroke. Therefore, the compressor is highly efficient while maintaining the reliability of the suction reed valve. Can be provided.

  The invention according to claim 2 is the invention according to claim 1, wherein the auxiliary valve seat is formed integrally with the valve seat, and the auxiliary valve seat is formed integrally with the valve seat so that the valve seat is formed. In addition to the effect of the invention according to claim 1, in addition to the effect of the invention according to claim 1, since the rigidity of the thin wall portion of the inner peripheral portion can be increased and the deformation of the valve seat contact surface can be reduced even under conditions where high pressure acts during the compression stroke. And deterioration of reliability can be prevented.

  The invention according to claim 3 is the invention according to claim 1, wherein the auxiliary valve seat is formed separately from the valve seat, and the auxiliary valve seat provided on the inner peripheral portion of the valve seat is separate. Since the contact distance in the radial direction of the valve seat contact surface is short due to the body, the rigidity of the thin portion of the inner periphery of the valve seat can be increased while reducing the increase in contact force when the suction reed valve begins to open, and is high during the compression stroke Since the deformation of the valve seat contact surface can be reduced even under conditions where pressure acts, in addition to the effect of the invention of claim 1, the sealing performance is further reduced while reducing the increase in contact force when the suction reed valve starts to open. And deterioration of reliability can be prevented.

  The invention according to claim 4 is the invention according to claim 1, wherein the auxiliary valve seat has a concentric shape with the circular portion of the valve seat, and the circumferential stress at the time of the discharge pressure action of the suction reed valve is The auxiliary valve provided on the inner periphery of the valve seat shows a stress distribution that is concentric with the circular portion in proportion to the square of the inner diameter of the valve seat, and the deformation also shows a deformed shape that is concentric with the circular portion. The seat according to claim 1, wherein the seat has a concentric shape along the stress distribution and the deformed shape, so that local stress concentration due to a change in the deformed shape caused by the auxiliary valve seat can be avoided. In addition to the effects of the invention, a highly reliable compressor can be provided.

  The invention according to claim 5 is the invention according to claim 1, wherein the valve seat plate is molded from a sintered material, and the shape of the valve seat provided on the valve seat plate is not a simple circle. Even if it has a complicated shape with an auxiliary valve seat inside the circular part of the valve seat, it is molded with a sintered material in which metal powder is sealed in a mold and then molded by pressurization and heating In addition to the effect of the invention of claim 1, further increase in the processing cost of the valve seat plate can be suppressed. .

  According to a sixth aspect of the present invention, in the first aspect of the present invention, since the center line of the suction reed valve and the center position of the circular part of the valve seat do not coincide with each other, the pressure in the compression chamber during the suction stroke decreases. The suction reed valve receives a differential pressure load due to the pressure difference between the compression chamber and the suction hole, and the point of action of the differential pressure load does not coincide with the center line of the suction reed valve. Since the shaft receives a torsional moment force and starts torsional deformation, the suction lead valve and the valve seat seal part are easily peeled off, and the opening of the suction reed valve can be started earlier to increase suction efficiency. Therefore, in addition to the effect of the first aspect of the invention, it is possible to further reduce the suction loss due to the delay in opening the suction reed valve during the suction stroke.

  According to a seventh aspect of the present invention, in the first aspect of the present invention, the electric element is inverter-driven at a plurality of operating frequencies, particularly during low speed operation with a small amount of refrigerant circulation, compression during the suction stroke. 2. The suction reed valve is likely to be delayed due to a slow pressure drop rate in the chamber. However, even during low speed operation, the suction reed valve can be opened earlier and the suction efficiency can be increased. In addition to the effects of the present invention, it is possible to reduce the suction loss due to the delay in opening the suction reed valve during the suction stroke even during low speed operation by inverter drive.

  According to an eighth aspect of the present invention, in the first aspect of the present invention, since the compression medium is a hydrocarbon refrigerant, and the pressure of the hydrocarbon refrigerant is low, the suction lead is reduced with a decrease in pressure in the compression chamber during the suction stroke. Although the differential pressure load due to the pressure difference between the compression chamber acting on the valve and the suction hole is small, the inner peripheral area of the valve seat can be expanded, so the differential pressure load acting on the suction reed valve increases and the suction reed valve begins to open. In addition to the effect of the invention of claim 1, the suction reed valve opens during the suction stroke even when the compression medium is a hydrocarbon refrigerant having a low pressure. Inhalation loss due to the delay can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments.

(Embodiment 1)
1 is a cross-sectional view of a compressor according to Embodiment 1 of the present invention, FIG. 2 is a cross-sectional view of essential parts of the compressor according to the same embodiment, and FIG. 3 is a valve seat plate of the compressor according to the same embodiment. FIG. 4 is a plan view of a suction reed valve of the compressor according to the embodiment.

  In FIGS. 1 to 4, the sealed container 101 contains an electric element 104 that includes a stator 102 and a rotor 103 and is inverter-driven at a plurality of operating frequencies, and a compression element 105 that is driven by the electric element 104. The suction pipe 106 is fixed to the closed vessel 101 and connected to the low pressure side (not shown) of the refrigeration cycle, and the discharge pipe (not shown) is fixed to the closed vessel 101 and the high pressure side of the refrigeration cycle (shown). (Not shown). An oil 107 is stored at the bottom of the sealed container 101.

  The refrigerant sealed in the sealed container 101 is hydrocarbon-based R600a, and the oil 107 is mineral oil or alkylbenzene.

  Next, the compression element 105 will be described.

  The crankshaft 110 has a main shaft portion 111 in which the rotor 103 is press-fitted and fixed, and an eccentric portion 112 formed eccentrically with respect to the main shaft portion 111. The cylinder 113 includes a bearing portion 115 that forms a substantially cylindrical compression chamber 114 and supports the main shaft portion 111. The piston 116 is inserted into the compression chamber 114 so as to be slidable back and forth, and is connected to the eccentric portion 112 by a connecting rod 117.

  The valve seat plate 120 that seals the opening end face of the compression chamber 114 is formed of an iron-based sintered material, and a suction hole 123 that opens into the compression chamber 114 is formed. A valve seat 121 is formed on the side surface of the opening end surface of the compression chamber 114 of the valve seat plate 120 so as to surround the suction hole 123.

  The valve seat 121 includes a circular portion 124 provided in a circular shape, and a plurality of auxiliary valve seats 126 a, 126 b, 126 c protruding from the circular portion 124 are formed integrally with the circular portion 124 on the inner peripheral side of the circular portion 124. ing. The inner diameter of the circular portion 124 of the valve seat 121 is larger than the inner diameter of the conventional valve seat 21, and the inner peripheral portions of the auxiliary valve seats 126 a, 126 b, 126 c are concentric with the circular portion 124 of the valve seat 121. It has an arc.

  The suction reed valve 122 that opens and closes the valve seat 121 and the plurality of auxiliary valve seats 126a, 126b, and 126c is formed of a flapper valve steel material having high fatigue strength.

  The center position 124 a of the circular portion 124 is offset with respect to the position of the center line 122 b of the suction reed valve 122.

  The cylinder head 130 forming the high pressure chamber is fixed to the opposite side of the compression chamber 114 via the valve seat plate 120.

  A suction muffler 132 formed of a synthetic resin and having an expansion space 131 communicates with the suction hole 123 and is fixed between the valve seat plate 120 and the cylinder head 130.

  The suction port 132 a of the suction muffler 132 opens into the space 101 a of the sealed container 101. 3 are a virtual line 140 of the bore inner diameter and a virtual line 141 of the suction reed valve.

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

  When the electric element 104 is energized, the rotor 103 and the crankshaft 110 fixed to the rotor 103 rotate, and the piston 116 reciprocates in the compression chamber 114 via the connecting rod 117 by the rotational movement of the eccentric portion 112. Do.

  The compression operation is performed by repeating the steps of suction, compression, and discharge in the compression chamber 114 by the reciprocating motion of the piston 116, and the refrigerant gas is sealed from the low-pressure side (not shown) of the refrigeration cycle. After passing through the space 101a in the container 101 and from the suction port 132a of the suction muffler 132 through the expansion space 131 and sucked from the suction hole 123 of the valve seat plate 120 and compressed in the compression chamber 114, a discharge pipe (not shown) And is discharged to the high-pressure side (not shown) of the refrigeration cycle connected to the sealed container 101.

  The oil 107 stored at the bottom of the sealed container 101 lubricates the sliding portion of the compression element 105 by an oil supply mechanism (not shown), and also seals the piston 116 in the compression chamber 114 and the suction reed valve. The sealing part 122 and the valve seat 121 are sealed.

  At this time, in the suction stroke, the suction reed valve 122 receives a differential pressure load determined by the product of the pressure difference between the compression chamber 114 and the suction hole 123 and the inner peripheral area of the valve seat 121 as the pressure in the compression chamber 114 decreases. When this differential pressure load becomes larger than the contact force due to the viscosity of the oil 107 of the suction reed valve 122 and the valve seat 121, the suction reed valve 122 starts to open. Therefore, if the pressure conditions are the same, the larger the inner peripheral area of the valve seat 121, the earlier the opening of the suction reed valve 122 can be accelerated, and the suction efficiency can be improved.

  On the other hand, in the compression stroke, circumferential stress acts on the suction reed valve 122 as the sealing portion of the suction reed valve 122 and the valve seat 121 is sealed as the pressure in the compression chamber 114 increases. The circumferential stress acting on the suction reed valve 122 increases as the differential pressure between the suction and discharge pressure increases, that is, as the amount of deformation of the suction reed valve 122 due to the differential pressure load increases. In addition, if the pressure conditions are the same, the larger the inner diameter of the valve seat 121, the larger the deformation amount of the suction reed valve 122 and the greater the circumferential stress, which may adversely affect the reliability of the suction reed valve 122. is there.

  Here, in the present embodiment, the inner diameter of the circular portion 124 of the valve seat 121 is increased, but since the auxiliary valve seats 126a, 126b, and 126c are provided on the inner peripheral portion of the valve seat 121, the suction lead is provided. The deformation of the valve 122 when the discharge pressure is applied is restricted, so that the amount of deformation can be reduced, so that the maximum stress acting can be reduced.

  Therefore, by increasing the inner diameter of the circular portion 124 of the valve seat 121, the differential pressure load during the suction stroke can be increased, and as a result, the opening of the suction reed valve 122 can be started earlier and the suction efficiency can be improved. it can.

  Therefore, it is possible to provide a highly efficient compressor while maintaining high reliability.

  Further, the auxiliary valve seats 126a, 126b, and 126c are formed integrally with the valve seat 121, and the rigidity of the thin portion 125 of the inner peripheral portion of the valve seat 121 can be increased by being formed integrally with the valve seat 121. . Therefore, deformation of the seal surface of the valve seat 121 can be reduced even under a condition where high pressure acts during the compression stroke.

  Accordingly, it is possible to prevent deterioration of reliability and sealing performance due to deformation of the sealing surface of the valve seat 121, and it is possible to provide a highly efficient compressor while maintaining high reliability.

  The auxiliary valve seats 126a, 126b, and 126c are concentric with the circular portion 124 of the valve seat 121 at the inner periphery, and act between the valve seat 121 and the discharge reed valve 122 when the discharge pressure is applied. The circumferential stress is concentric with the circular portion 124 of the valve seat 121, and the deformation is similarly concentric with the circular portion.

  Here, since the auxiliary valve seats 126a, 126b, and 126c provided on the inner peripheral portion of the valve seat 121 have a concentric shape along the stress distribution and the deformed shape, the deformed portion due to the discharge pressure of the suction reed valve 122 is formed. The maximum deformation amount can be reduced without extremely increasing the deformation curvature.

  That is, the maximum stress can be reduced while avoiding stress concentration due to an increase in the curvature of deformation.

  Therefore, it is possible to provide a highly efficient compressor while maintaining high reliability.

  Further, the valve seat plate 120 is formed of a sintered material, and the shape of the valve seat 121 provided on the valve seat plate 120 is not a simple circle, and the auxiliary valve seats 126a, 126b, 126c are formed in the circular portion 124. Even if it has a complicated shape like the above, the processing man-hours of the valve seat plate 120 molded with a sintered material in which metal powder is sealed in a mold and then molded by pressurization and heating are almost the same. Therefore, productivity hardly decreases.

  Therefore, it is possible to suppress a decrease in productivity of the valve seat plate 120.

  The oil 107 stored at the bottom of the sealed container 101 lubricates the sliding portion of the compression element 105 by an oil supply mechanism (not shown), and also seals the piston 116 in the compression chamber 114 and the suction reed valve. The sealing part 122 and the valve seat 121 are sealed. On the other hand, since the oil 107 is viscous, an adhesive force acts between the suction reed valve 122 and the valve seat 121, and the suction reed valve 122 is difficult to peel off from the valve seat 121.

  However, in the present embodiment, since the center line 122b of the suction reed valve 122 and the center position 124a of the circular portion 124 of the valve seat 121 do not coincide with each other, the suction reed valve 122 is reduced with the pressure drop in the compression chamber 114 during the suction stroke. Receives the differential pressure load due to the pressure difference between the compression chamber 114 and the suction hole 123, and the point of action of the differential pressure load does not coincide with the center line 122b of the suction reed valve 122. Since it receives a torsional moment force about the center line 122b and starts torsional deformation, the seal between the suction reed valve 122 and the valve seat 121 is easily peeled off, and the opening of the suction reed valve 122 starts earlier. Inhalation efficiency.

  Accordingly, it is possible to reduce the suction loss due to the delay in opening the suction reed valve 122 during the suction stroke, and it is possible to provide a highly efficient compressor.

  In addition, the electric element 104 is inverter-driven at a plurality of operating frequencies. In particular, during low-speed operation with a small amount of refrigerant circulation, the pressure reduction rate of the compression chamber 114 during the intake stroke is slow, so the suction reed valve 122 is opened. Although a delay is likely to occur, the differential pressure load acting on the suction reed valve 122 increases because the inner peripheral area of the valve seat 121 is enlarged even during low-speed operation, and the opening of the suction reed valve 122 starts early. Inhalation efficiency.

  Therefore, even during low-speed operation by inverter driving, the suction loss due to the delay in opening the suction reed valve 122 during the suction stroke can be reduced, and a highly efficient compressor can be provided.

  Further, since the compression medium is a hydrocarbon refrigerant and the pressure of the hydrocarbon refrigerant is low, the pressure difference between the compression chamber 114 and the suction hole 123 acting on the suction reed valve 122 as the pressure of the compression chamber 114 decreases during the suction stroke. Although the differential pressure load due to the pressure is small, the inner peripheral area of the valve seat 121 is increased, so that the differential pressure load acting on the suction reed valve 122 is increased and the opening of the suction reed valve 122 is started earlier to increase the suction efficiency. Can do.

  Thus, the efficiency (COP) improvement effect in the present embodiment is that the input is reduced by 1% and the refrigeration performance is increased by 1% by reducing the suction loss in the standard operating condition of the refrigerator compressor using the R600a refrigerant. The effect of COP improvement by 2% was confirmed.

  Therefore, even when the compression medium is a low-pressure hydrocarbon refrigerant, the suction loss due to the delay in opening the suction reed valve 122 during the suction stroke can be reduced, and a highly efficient compressor can be provided.

  In the present embodiment, three auxiliary valve seats have been illustrated and described, but it goes without saying that the same action and effect can be obtained if there are one or more.

(Embodiment 2)
5 is a cross-sectional view of the compressor according to the second embodiment of the present invention, FIG. 6 is a cross-sectional view of the main part of the compressor according to the same embodiment, and FIG. 7 is a valve seat plate of the compressor according to the same embodiment. FIG. 8 is a plan view of a suction reed valve of the compressor according to the embodiment.

  5 to 8, the sealed container 201 accommodates an electric element 204 that includes a stator 202 and a rotor 203 and is inverter-driven at a plurality of operating frequencies, and a compression element 205 that is driven by the electric element 204. The suction pipe 206 is fixed to the sealed container 201 and connected to the low pressure side (not shown) of the refrigeration cycle, and the discharge pipe (not shown) is fixed to the sealed container 201 and the high pressure side of the refrigeration cycle (shown). (Not shown). In addition, oil 207 is stored at the bottom of the sealed container 201.

  The refrigerant sealed in the hermetic container 201 is hydrocarbon R600a, and the oil 107 is mineral oil or alkylbenzene.

  Next, the compression element 205 will be described.

  The crankshaft 210 has a main shaft portion 211 in which the rotor 203 is press-fitted and fixed, and an eccentric portion 212 formed eccentric to the main shaft portion 211. The cylinder 213 includes a bearing portion 215 that forms a substantially cylindrical compression chamber 214 and supports the main shaft portion 211. The piston 216 is inserted into the compression chamber 214 so as to be slidable back and forth, and is connected to the eccentric portion 212 by a connecting rod 217.

  The valve seat plate 220 that seals the opening end face of the compression chamber 214 is formed of an iron-based sintered material, and a suction hole 223 that opens into the compression chamber 214 is formed. A valve seat 221 is formed on the side surface of the opening end surface of the compression chamber 214 of the valve seat plate 220 so as to surround the suction hole 223.

  The valve seat 221 includes a circular portion 224 provided in a circular shape, and a plurality of auxiliary valve seats 226 a, 226 b, and 226 c are formed separately from the circular portion 224 on the inner peripheral side of the circular portion 224. The inner diameter of the circular portion 224 of the valve seat 221 is formed larger than the inner diameter of the conventional valve seat 21, and the inner peripheral portions of the auxiliary valve seats 226 a, 226 b, and 226 c are concentric with the circular portion 224 of the valve seat 221. It has an arc.

  The suction reed valve 222 that opens and closes the valve seat 221 and the plurality of auxiliary valve seats 226a, 226b, and 226c is formed of a flapper valve steel material having high fatigue strength.

  The center position 224 a of the circular portion 224 is offset with respect to the position of the center line 222 b of the suction reed valve 222.

  The cylinder head 230 forming the high pressure chamber is fixed to the opposite side of the compression chamber 214 via the valve seat plate 220.

  A suction muffler 232 formed of a synthetic resin and having an expansion space 231 communicates with the suction hole 223 and is fixed between the valve seat plate 220 and the cylinder head 230.

  The suction port 232 a of the suction muffler 232 opens into the space 201 a of the sealed container 201. The two-dot chain line shown in FIG. 7 is a virtual line 240 of the bore inner diameter and a virtual line 241 of the suction reed valve.

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

  When the electric element 204 is energized, the rotor 203 and the crankshaft 210 fixed to the rotor 203 rotate, and the piston 216 reciprocates in the compression chamber 214 via the connecting rod 217 by the rotational movement of the eccentric portion 212. Do.

  The reciprocating motion of the piston 216 repeats the suction, compression, and discharge strokes in the compression chamber 214, and the refrigerant gas is compressed from the low pressure side (not shown) of the refrigeration cycle. After passing through the space 201 a in the container 201 and from the suction port 232 a of the suction muffler 232 through the expansion space 231 and sucked from the suction hole 223 of the valve seat plate 220 and compressed in the compression chamber 214, a discharge pipe (not shown) And is discharged to the high-pressure side (not shown) of the refrigeration cycle connected to the sealed container 201.

  The oil 207 stored in the bottom of the sealed container 201 lubricates the sliding portion of the compression element 205 by an oil supply mechanism (not shown), and also seals the piston 216 in the compression chamber 214 and the suction reed valve. The seal part between 222 and the valve seat 221 is sealed.

  At this time, in the suction stroke, the suction reed valve 222 receives a differential pressure load determined by the product of the pressure difference between the compression chamber 214 and the suction hole 223 and the inner peripheral area of the valve seat 221 as the pressure in the compression chamber 214 decreases. When this differential pressure load becomes larger than the contact force due to the viscosity of the oil 207 in the suction reed valve 222 and the valve seat 221, the suction reed valve 222 starts to open. Therefore, if the pressure conditions are the same, the larger the inner peripheral area of the valve seat 221, the earlier the opening of the suction reed valve 222 can be accelerated, and the suction efficiency can be improved.

  On the other hand, in the compression stroke, circumferential stress acts on the suction reed valve 222 when the sealing portion of the suction reed valve 222 and the valve seat 221 is sealed as the pressure in the compression chamber 214 increases. The circumferential stress acting on the suction reed valve 222 increases as the differential pressure between the suction and discharge pressure increases, that is, as the amount of deformation of the suction reed valve 222 due to the differential pressure load increases. Further, if the pressure conditions are the same, the larger the inner diameter of the valve seat 221, the larger the deformation amount of the suction reed valve 222, and the circumferential stress increases, which may adversely affect the reliability of the suction reed valve 222. is there.

  Here, in the present embodiment, the inner diameter of the circular portion 224 of the valve seat 221 is increased. However, since the auxiliary valve seats 226a, 226b, and 226c are provided on the inner peripheral portion of the valve seat 221, the suction lead is provided. The deformation of the valve 222 when the discharge pressure is applied is restricted, and the amount of deformation can be reduced, so that the maximum stress acting can be reduced.

  Therefore, by increasing the inner diameter of the circular portion 224 of the valve seat 221, the differential pressure load during the intake stroke can be increased, and as a result, the opening of the intake reed valve 222 is started earlier and the intake efficiency is improved. it can.

  Therefore, it is possible to provide a highly efficient compressor while maintaining high reliability.

  Further, the auxiliary valve seats 226a, 226b, and 226c are formed separately from the valve seat 221, and the rigidity of the thin portion 225 of the inner peripheral portion of the valve seat 221 can be increased, and the auxiliary valve seats 226a, 226b, and 226c can be increased. However, since the sealing distance in the radial direction of the seal surface is short and the amount of increase in the seal area can be reduced, an increase in the adhesion force when the suction reed valve 222 starts to open can be reduced.

  Therefore, it is possible to prevent the deterioration of the reliability and the sealing performance due to the deformation of the sealing surface of the valve seat 221 and the significant increase in the adhesion force, and it is possible to provide a highly efficient compressor while maintaining the high reliability.

  The auxiliary valve seats 226a, 226b, and 226c have an inner circumference that is concentric with the circular portion 224 of the valve seat 221. The auxiliary valve seats 226a, 226b, and 226c act between the valve seat 221 when the suction reed valve 222 operates on the discharge pressure. The circumferential stress is concentric with the circular portion 224 of the valve seat 221, and the deformation is similarly concentric with the circular portion.

  Here, since the auxiliary valve seats 226a, 226b, and 226c provided on the inner peripheral portion of the valve seat 221 have a concentric shape along the stress distribution and the deformed shape, the deformed portion due to the discharge pressure of the suction reed valve 222. The maximum deformation amount can be reduced without extremely increasing the deformation curvature.

  That is, the maximum stress can be reduced while avoiding stress concentration due to an increase in the curvature of deformation.

  Therefore, it is possible to provide a highly efficient compressor while maintaining high reliability.

  Further, the valve seat plate 220 is formed of a sintered material, and the shape of the valve seat 221 provided on the valve seat plate 220 is not a simple circle, and the auxiliary valve seats 226a, 226b, 226c are formed in the circular portion 224. Even if it has a complicated shape as described above, the processing man-hours of the valve seat plate 220 molded with a sintered material in which metal powder is encapsulated in a mold and then molded by pressurization and heating are almost unchanged. Therefore, productivity hardly decreases.

  Therefore, a decrease in productivity of the valve seat plate 220 can be suppressed.

  The oil 207 stored in the bottom of the sealed container 201 lubricates the sliding portion of the compression element 205 by an oil supply mechanism (not shown), and also seals the piston 216 in the compression chamber 214 and the suction reed valve. The seal part between 222 and the valve seat 221 is sealed. On the other hand, since the oil 207 is viscous, an adhesive force acts between the suction reed valve 222 and the valve seat 221, and the suction reed valve 222 is difficult to peel off from the valve seat 221.

  However, in the present embodiment, since the center line 222b of the suction reed valve 222 and the center position 224a of the circular portion 224 of the valve seat 221 do not coincide with each other, the suction reed valve 222 is reduced as the pressure in the compression chamber 214 decreases during the suction stroke. Receives the differential pressure load due to the pressure difference between the compression chamber 214 and the suction hole 223, and the point of action of the differential pressure load does not coincide with the center line 222b of the suction reed valve 222. Since the torsional moment force is received about the center line 222b and the torsional deformation starts to open, the seal portion between the suction reed valve 222 and the valve seat 221 is easily peeled off, and the opening of the suction reed valve 222 starts earlier. Inhalation efficiency.

  Therefore, it is possible to reduce the suction loss due to the delay in opening the suction reed valve 222 during the suction stroke, and it is possible to provide a highly efficient compressor.

  In addition, the electric element 204 is inverter-driven at a plurality of operating frequencies. In particular, during low-speed operation with a small amount of refrigerant circulation, the pressure reduction rate of the compression chamber 214 during the intake stroke is slow, so the suction reed valve 222 opens. Although a delay is likely to occur, the differential pressure load acting on the suction reed valve 222 increases because the area of the inner periphery of the valve seat 221 is enlarged even during low speed operation, and the opening of the suction reed valve 222 starts early. Inhalation efficiency.

  Therefore, even during low-speed operation by inverter driving, the suction loss due to the delay in opening the suction reed valve 222 during the suction stroke can be reduced, and a highly efficient compressor can be provided.

  Further, since the compression medium is a hydrocarbon refrigerant, and the pressure of the hydrocarbon refrigerant is low, the pressure difference between the compression chamber 214 and the suction hole 223 acting on the suction reed valve 222 as the pressure in the compression chamber 214 decreases during the suction stroke. Although the differential pressure load due to the pressure is small, the inner peripheral area of the valve seat 221 is enlarged, so that the differential pressure load acting on the suction reed valve 222 is increased, and the opening of the suction reed valve 222 is accelerated to increase the suction efficiency. Can do.

  Thus, the efficiency (COP) improvement effect in the present embodiment is that the input is reduced by 1% and the refrigeration performance is increased by 1% by reducing the suction loss in the standard operating condition of the refrigerator compressor using the R600a refrigerant. The effect of COP improvement by 2% was confirmed.

  Therefore, even when the compression medium is a low-pressure hydrocarbon refrigerant, the suction loss due to the delay in opening the suction reed valve 222 during the suction stroke can be reduced, and a highly efficient compressor can be provided.

  In the present embodiment, three auxiliary valve seats have been illustrated and described, but it goes without saying that the same action and effect can be obtained if there are one or more.

  As described above, the compressor according to the present invention can improve the suction efficiency by early opening of the suction reed valve during the suction stroke while preventing an increase in the stress acting on the suction reed valve, and has high reliability. Since it becomes possible to achieve high efficiency while maintaining, it can also be applied to applications such as vending machines, refrigeration showcases, and dehumidifiers.

Sectional drawing of the compressor in Embodiment 1 of this invention Sectional drawing of the principal part of the compressor in the embodiment Valve seat plate plan view of the compressor in the same embodiment Compressor suction reed valve plan view of the same embodiment Sectional drawing of the compressor in Embodiment 2 of this invention Sectional drawing of the principal part of the compressor in the embodiment Valve seat plate plan view of the compressor in the same embodiment Compressor suction reed valve plan view of the same embodiment Cross section of a conventional compressor Sectional view of the suction reed valve part of a conventional compressor Plan view of valve seat plate of conventional compressor Conventional compressor intake reed valve top view

Explanation of symbols

104, 204 Electric element 113, 213 Cylinder 116, 216 Piston 120, 220 Valve seat plate 121, 221 Valve seat 122, 222 Suction reed valve 122b, 222b Center line 123, 223 Suction hole 124, 224 Circular portion 124a, 224a Center position 126a, 126b, 126c, 226a, 226b, 226c Auxiliary valve seat

Claims (8)

  A cylinder that houses a reciprocating piston, a valve seat plate that is disposed at the opening end of the cylinder and that has a suction hole, and is provided on the opening end side of the cylinder of the valve seat plate so as to surround the suction hole And a suction reed valve provided between the open end and the valve seat plate for opening and closing the valve seat, and having an auxiliary valve seat on the inner periphery of the valve seat.   The compressor according to claim 1, wherein the auxiliary valve seat is formed integrally with the valve seat.   The compressor according to claim 1, wherein the auxiliary valve seat is formed separately from the valve seat.   The compressor according to claim 1, wherein the auxiliary valve seat has a concentric shape with a circular portion of the valve seat.   The compressor according to claim 1, wherein the valve seat plate is formed of a sintered material.   The compressor according to claim 1, wherein the center line of the suction reed valve and the center position of the circular part of the valve seat do not coincide.   The compressor according to claim 1, wherein the electric element is inverter-driven at a plurality of operating frequencies.   The compressor according to claim 1, wherein the compression medium is a hydrocarbon refrigerant.

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