JP2012013025A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce pressure loss in a check valve to reduce density of intake gas and reduce a discharge flow rate, during normal operation.SOLUTION: An intake valve 18 disposed in an intake passage to prevent a back flow of refrigerant gas has a valve having a dual-partitioned plate shape, and the valve is configured to turn with a rotation axis provided on a partitioned surface side of each valve as the center.

Description

  The present invention relates to a scroll compressor, and more particularly to a structure that reduces pressure loss of a suction valve.

  When the scroll compressor is stopped, the high-pressure gas on the discharge side tends to flow back to the suction side through the compression mechanism. When this reverse flow phenomenon occurs, the compression mechanism is rotated in the opposite direction to the compression by the power generated by the gas expansion, and the electric circuit is adversely affected by the generation of noise and the electromotive force generated by the reverse rotation of the motor. For this reason, in the conventional scroll compressor, as shown in FIG. 11, a suction valve having a check valve structure including a spring and a valve body is provided on the suction side of the fixed scroll. However, this suction valve has a problem that, during normal operation, pressure loss occurs due to the compression of the spring by the refrigerant flow, reducing the density of the suction gas and reducing the discharge flow rate. Patent Document 1 discloses a scroll compressor that reduces the pressure loss of the suction valve.

JP 2004-124830 A

  In Patent Document 1, a valve body provided in an intake chamber so as to be able to close an intake port, a guide part connected to the valve body and a support rod and provided to be able to reciprocate in the intake pipe, and an intake pipe are provided. By providing the spring for biasing the guide portion so that the valve body closes the suction port, a sufficient suction passage area for the refrigerant gas in the suction portion of the compressor can be secured, so that the suction pressure loss is reduced and the compressor is reduced. It can improve efficiency.

  However, Patent Document 1 includes a spring that biases the guide portion, and the spring must be deflected by the flow of the refrigerant gas when sucked. The force that deflects the spring is due to a pressure difference acting on the guide portion side and the valve body side of the spring, and this pressure difference is a pressure loss of the refrigerant gas. In addition, since the flow of the refrigerant gas changes over time due to the influence of pulsation and increase / decrease in the number of rotations of the motor, the check valve is not always fully open even when the compressor is operating, Pressure loss due to the reduction can occur. Thus, in Patent Document 1, there is a pressure loss that occurs because the check valve has a spring.

  The present invention aims to reduce the above-mentioned pressure loss.

The purpose of the present invention is to
In a scroll compressor that is provided in a flow path for sucking refrigerant gas and includes a check valve that prevents reverse flow of the refrigerant gas, a turning scroll, and a fixed scroll,
The check valve is a valve body having a shape in which a plate is divided in two on a plane passing through the center, and is a valve that can be rotated around a rotation shaft provided on the surface side of each divided valve body. This is achieved by a scroll compressor having a body.

In addition,
The flow path is configured by a casing press-fitted into the fixed scroll and a pipe press-fitted into the casing so as to sandwich the valve body between the casing and
Provided with a groove for holding the rotating shaft in the housing, and provided with a pin for rotatably holding the rotating shaft in the groove,
While avoiding the pin, provided a notch in the rotating shaft so that the end of the pin can be the center of rotation,
This is achieved by inserting the rotary shaft into the groove to hold the valve body rotatably.

  According to the present invention, the pressure loss of the refrigerant can be reduced.

The longitudinal cross-sectional view of the scroll compressor in this invention. The expanded view of the suction valve in this invention. The longitudinal cross-sectional view of the suction valve in this invention. The state figure of opening of the suction valve in this invention. The state figure of closing of the suction valve in the present invention. Explanatory drawing of the rotating shaft of a valve body. Operation | movement explanatory drawing of the rotating shaft of a valve body. Comparison of annual energy efficiency with and without conventional suction valve spring. 2nd Embodiment figure (horizontal suction scroll compressor). FIG. 3 is a third embodiment (horizontal type scroll compressor). The state figure of opening of a conventional suction valve. The state figure of closing of a conventional suction valve. The enlarged view near the rotating shaft end of a valve body. The valve body figure of 4th Embodiment. The longitudinal cross-sectional view (rotation axis parallel cross section) of 4th Embodiment. The longitudinal cross-sectional view (4th direction of a rotating shaft) of 4th Embodiment.

  Hereinafter, embodiments will be described with reference to the drawings.

  The first embodiment of the present invention will be described in detail below. In the following embodiments, it is assumed that the check valve in the present invention is a suction valve provided in the suction portion.

  The basic operation of the scroll compressor will be described with reference to FIG. The scroll compressor 1 includes a compression mechanism unit 3 including a turning scroll 6 provided with a spiral wrap 6a and a fixed scroll 5 provided with a spiral wrap 5c, and an electric motor 4 for driving the compression mechanism unit 3. The airtight container 2 that houses the compression mechanism 3 and the electric motor 4 is provided. A compression mechanism unit 3 is disposed in the upper part of the sealed container 2, and an electric motor 4 is disposed in the lower part. A lubricating oil 13 is stored at the bottom of the sealed container 2.

  The sealed container 2 is configured by welding a cylindrical chamber 2a with a lid chamber 2b on the top and a bottom chamber 2c on the bottom. The lid chamber 2b is provided with a suction pipe 2d, and a discharge pipe 2e is provided on the side surface of the case 2a. The inside of the sealed container 2 is a discharge pressure chamber 2f.

  The compression mechanism unit 3 is integrated with the fixed scroll 5 having the spiral wrap 5c on the base plate 5d, the orbiting scroll 6 having the spiral wrap 6a on the base plate 6b, and the fixed scroll 5 with a bolt 8. And a frame 9 that supports the orbiting scroll 6.

  The frame 9 includes a main bearing 9a that rotatably supports the crankshaft 7. An eccentric portion 7 b of the crankshaft 7 is connected to the lower surface side of the orbiting scroll 6.

  An Oldham ring 12 is disposed between the lower surface side of the orbiting scroll 6 and the frame 9. The Oldham ring 12 is mounted in a groove formed on the lower surface side of the orbiting scroll 6 and a groove formed on the frame 9. Yes. The Oldham ring 12 functions to revolve by receiving the eccentric rotation of the eccentric portion 7 b of the crankshaft 7 without rotating the orbiting scroll 6.

  The electric motor 4 includes a stator 4a and a rotor 4b. The stator 4a is fastened to the sealed container 2 by press-fitting or welding. The rotor 4b is rotatably arranged in the stator 4a. A crankshaft 7 is fixed to the rotor 4b.

  The crankshaft 7 includes a main shaft 7 a and an eccentric portion 7 b and is supported by a main bearing 9 a and a lower bearing 17 provided on the frame 9. The eccentric portion 7 b is formed integrally with the main shaft 7 a of the crankshaft 7, and is fitted to a orbiting bearing 6 c provided on the back surface of the orbiting scroll 6. The crankshaft 7 is driven by the electric motor 4, and the eccentric portion 7b is eccentrically rotated with respect to the main shaft 7a, thereby causing the orbiting scroll 6 to orbit. Further, the crankshaft 7 is provided with an oil supply passage 7c that guides the lubricating oil 13 to the main bearing 9a, the lower bearing 17 and the slewing bearing 6c.

  When the orbiting scroll 6 orbits through the crankshaft 7 driven by the electric motor 4, the refrigerant gas is guided from the suction pipe 2d to the compression chamber 11 formed by the orbiting scroll 6 and the fixed scroll 5, and the center direction of the scroll The volume is reduced and compressed as it moves. The compressed refrigerant gas is discharged from the discharge port 5e provided at the approximate center of the base plate 5d of the fixed scroll 5 to the discharge pressure chamber 2f in the sealed container 2, and flows out from the discharge pipe 2e to the outside.

  FIG. 2 is a development view of the suction valve. A suction valve 18 is installed in the suction pipe 2d. The suction valve 18 includes a casing 18a that is press-fitted into a fixed scroll, a pin 18c that is inserted into a hole 18b of the casing 18a, a valve body 18f in which a rotating shaft 18e is inserted into a groove 18d of the casing 18a, and the rotation The suction pipe 2d is press-fitted into the housing 18a so that the shaft 18e does not protrude from the groove 18d, and is assembled in the positional relationship shown in the drawing. The valve body is made of resin, for example. This is because a metal valve may generate a loud noise when it is closed.

  As shown in FIG. 3, the pin 18c is inserted into the hole 18b of the housing 18a, and the rotating shaft 18e of the valve body 18f is inserted into the groove 18d from above.

  A series of operations of the suction valve 18 from when the compressor is operated until it completely stops will be described. FIG. 4 is a cross-sectional view shown in FIG. 3 in which the suction valve 18 is open. When the check valve is in an equilibrium state, the check valve is open when the check valve is in an equilibrium state between the up and down sides, the far side, and this side, that is, the suction side and the discharge side of the scroll compressor.

  When the scroll compressor 1 is in operation, the refrigerant gas flows in the direction from the top to the bottom of FIG. At this time, the valve body 18f is pushed toward the center side by the refrigerant flowing on the surface of the valve body 18f, so that the notch 18i of the rotating shaft 18e and the pin 18c are in contact with each other.

  When the operation is stopped, the energization of the electric motor 4 is cut off and torque is not generated. Then, the high-pressure refrigerant confined in the compression chamber constituted by the spiral wraps 5 c and 6 a causes the electric motor 4 to rotate in the reverse direction. In this way, the discharge gas flows backward through the compression mechanism unit 3, that is, the refrigerant gas flows in the direction from the bottom to the top of FIG.

  The surface of the valve body 18f on the housing side is tapered so that the thickness decreases toward the outer peripheral side. This is not a tapered shape radially, but if the rotation axis 18e of the valve body 18f is the x-axis, the tapered shape is formed as the absolute value in the y-axis direction increases.

  1 and 4, when the refrigerant gas flows from the bottom to the top, the refrigerant gas flows into the gap of the taper 18g of the valve body 18f. When the refrigerant gas flows into the gap, the valve body 18f tries to expand due to the dynamic pressure, and actually expands, so that the suction valve 18 is closed as shown in FIG. At the moment when the suction valve 18 is closed, there is a pressure difference between the upper and lower sides of the valve body 18f. The upper pressure is almost the suction pressure, and the lower pressure is the discharge pressure. Due to this pressure difference, a pressing force F acts on the taper 18g of the valve body 18f.

  At this time, the component force of the pressing force F becomes Fcosθ and Fsinθ using the angle θ of the tapered portion, and the outer peripheral portion of the valve body 18f is pressed against the end surface 2g of the suction pipe 2d by the force of Fcosθ. The valve bodies 18f are pressed against each other at the dividing surface 18h (see, for example, FIG. 6) with a force of Fsinθ. Thereby, the outer peripheral part of the valve body 18f and the dividing surface 18h are sealed, and the refrigerant gas does not flow backward even when the operation is stopped.

  In addition to this phenomenon, the refrigerant flows from the discharge pipe side to the suction pipe side through the refrigeration cycle, the pressure difference between the discharge pressure and the suction pressure becomes smaller, and reaches an equilibrium state after a sufficiently long time. . At this time, the valve body 18f is in the state of FIG. 4 due to gravity.

  Next, the stability of the valve body 18f at the moment when the suction valve 18 is about to be closed will be described with reference to FIGS. FIG. 7 is a view in the same direction as the cross-sectional view as shown in FIG. (A) is a state in which the valve is open, and when the check valve is open, the valve body 18f hangs down in the direction of gravity. (B) is a state in which the valve is closed. When the check valve is closed, the outer peripheral portion of the valve body 18f is in contact with the end surface of the suction pipe 2d and the valve bodies are in contact with each other at the dividing surface 18h. .

  The rotary shaft 18e of the valve body 18f is provided with a notch 18i (for example, see FIG. 6). When the valve body 18f is inserted into the groove 18d, the notch 18i is installed to avoid the pin 18c. With such a structure, the right side valve element 18f in FIG. 7 is restricted from rotating from the 6 o'clock direction to the clockwise direction by the contact of the notch 18i and the pin 18c. As for 18f, the rotation from the 6 o'clock direction to the counterclockwise direction is restricted by the contact between the notch 18i and the pin 18c. By restricting the movement of the valve body 18f, when the scroll compressor 1 is stopped and the refrigerant gas flows from the bottom to the top in FIG. 7, the two valve bodies 18f are prevented from rotating in the same direction. . That is, the phenomenon that the valve body 18f does not expand and the suction valve 18 closes only half is prevented.

  FIG. 8 compares the annual energy efficiency when the conventional suction valve type scroll compressor shown in FIGS. 11 and 12 is mounted on a room air conditioner and when the spring 19 is present and not present. The improvement rate when the spring presence is set to 1 is shown.

  FIG. 11 shows a state where the suction valve is open, and FIG. 12 shows a state where the suction valve is closed. Here, the annual energy efficiency is a value obtained by dividing the heat load of the air conditioner throughout the year by the power consumption. In the conventional suction valve 20, the spring 19 is inserted into the suction port 21 of the fixed scroll 5, and the valve body 22 is inserted from above. When the compressor is started, the refrigerant gas flows from the top to the bottom in the suction pipe 2d. By this flow, the valve body 22 is pushed, the spring 19 is bent, and the refrigerant gas is sucked into the wrap of the fixed scroll 5 and the orbiting scroll 6.

  As shown in FIG. 8, when there is no spring 19, annual energy efficiency is high compared with the case where it exists. The force that deflects the spring 19 is due to the pressure difference acting on the upper and lower surfaces of the spring 19, and this pressure difference becomes the pressure loss of the refrigerant gas.

  By removing the spring 19, this pressure loss is eliminated, and the refrigerant gas is sucked into the wrap of the fixed scroll 5 and the orbiting scroll 6 at substantially the same pressure as the inlet pipe 2 d inlet. Therefore, the density of the refrigerant gas in the wrap does not decrease, and the discharge circulation amount of the scroll compressor increases. If the discharge circulation volume increases, if the cooling (heating) capacity as a room air conditioner is made constant, the rotation speed of the scroll compressor can be lowered, the power consumption of the scroll compressor is reduced, and the annual energy efficiency is increased. be able to.

  As described above, in the first embodiment, the suction valve 18 is provided to prevent reverse rotation of the electric motor 4 due to the reverse flow of the refrigerant gas when the scroll compressor 1 is stopped, and the suction valve 18 does not require a spring. Thus, the pressure loss when the refrigerant gas is sucked into the wrap of the fixed scroll 5 and the orbiting scroll 6 can be reduced, and the annual energy efficiency is increased.

  In the present embodiment, the valve body has a shape obtained by dividing the disk into two parts, but the effect of the present embodiment can be obtained in the same manner even if a valve body in which the shape other than the disk is divided into two parts is used.

  FIG. 9 shows a second embodiment. The scroll compressor shown in FIG. 9 has substantially the same configuration as that of the first embodiment, and those having the same name and the same sign can obtain the same operational effects. The difference between the second embodiment and the first embodiment is that the flow direction of the refrigerant gas sucked into the wrap of the fixed scroll 5 and the orbiting scroll 6 is horizontal. Since the refrigerant gas in the compression chamber 11 is compressed toward the center of the wrap, the fact that the refrigerant gas is sucked sideways means that the refrigerant gas is sucked in the same plane as the plane perpendicular to the axis to be compressed. . This is advantageous in that the suction becomes smooth and the pressure loss can be reduced. Since the suction valve 18 can be easily assembled as shown in FIG. 2, the suction valve 18 can be easily attached to the pipe outside the sealed container 2 even when the refrigerant gas is sucked sideways. When installing, if it is attached to a pipe that is relatively close to the scroll compressor and has a vertical orientation, the same effect as in the first embodiment is obtained, and the annual energy efficiency is increased.

  FIG. 10 shows a third embodiment. The scroll compressor shown in FIG. 10 has substantially the same configuration as that of the first embodiment, and the same function and effect can be obtained with the same name and the same reference numerals. The difference between the third embodiment and the first embodiment is that the scroll compressor 1 is a horizontal type. Depending on the product, the horizontal type makes it easier to arrange heat exchangers and the like, and the unit space can be used effectively. For example, a horizontal type is often used for a showcase installed in a convenience store or a supermarket. As shown in FIG. 10, since the suction valve 18 can be easily assembled, even a horizontal type scroll compressor can be easily attached to the pipe outside the sealed container 2. When attached to the suction side pipe, which is relatively close to the scroll compressor and the orientation of the outside of the scroll compressor is vertical, the same effect as in the first embodiment is obtained, and the annual energy efficiency is increased.

  The fourth embodiment will be described with reference to FIGS. FIG. 13 is an enlarged view of the vicinity of one end of the rotary shaft 18e when the valve of the first to third embodiments is closed, FIG. 14 is a view of the valve body of the suction valve in the fourth embodiment, and FIG. FIG. 16 is a longitudinal sectional view in the vicinity of the suction valve in the fourth embodiment, and FIG. 16 is a longitudinal sectional view during the operation of closing the suction valve in the fourth embodiment.

  The purpose of this embodiment is that when the valve is closed, the suction valve and the suction pipe 2d are in contact with each other in the annular region indicated by A in FIG. It is to improve that the sealing effect is partially lowered by forming a line instead of a surface and further reducing the refrigerant backflow.

  Although not mentioned in FIG. 7 and the like, it is added here that the valve body 18f does not rotate unless it is as shown in FIG.

  In the present embodiment, in order to reduce the leakage at the time of closing the valve, as shown in FIG. 14, the portion C is not rounded along the rotary shaft 18e, and the contact portion of the suction valve with the suction pipe 2d side is reduced. A valve element 18f that is entirely a surface is used. Further, in order to prevent the portion C from popping out to the suction pipe 2d side when the valve is opened and closed and hindering the rotation of the valve body, as shown in FIG. 15, a ring 24 having a slightly smaller outer diameter than the suction pipe 2d is provided at the upper part of the valve. Further, a coil spring 23 having a diameter not less than the inner diameter and less than the outer diameter of the suction pipe 2d is disposed between the ring 24 and the suction pipe 2d. Further, the lower end of the suction pipe 2d has an inner diameter that is expanded according to the coil spring 23 as shown in the figure. With these structures, as shown in FIG. 16, when the valve is closed, the ring 24 is once lifted so that the rotation is not hindered, and the valve body is moved in the vertical direction by the protrusion outside the lower end of the suction pipe 2d. And the coil spring 23 is compressed by the refrigerant pressure difference and the suction valve can be prevented from popping out.

  As described above, the portion in contact with the valve body 18f and the portion on the suction pipe 2d side, that is, the portion far from the housing 18a has a structure including an elastic body, and the valve body according to opening and closing of the check valve By adopting a structure that can move while maintaining contact with 18f, the ring 24 and the valve element 18f are in surface contact in the entire circumference in the leakage path passing through the inside of the ring 24, and the ring and suction in the leakage path passing through the outside of the ring 24. Since the pipe 2d is in surface contact with the entire circumference, leakage of the refrigerant passing through the suction valve when the compressor is stopped can be further reduced.

DESCRIPTION OF SYMBOLS 1 Scroll compressor 2 Sealed container 2a Case 2b Cover chamber 2c Bottom chamber 2d Suction pipe 2e Discharge pipe 2f Discharge pressure chamber 2g End surface 3 Compression mechanism part 4 Electric motor 4a Stator 4b Rotor 5 Fixed scroll 5c, 6a Wraps 5d, 6b Plate 5e Discharge port 6 Orbiting scroll 6c Orbiting bearing 7 Crankshaft 7a Main shaft 7b Eccentric portion 7c Oil supply passage 8 Bolt 9 Frame 9a Main bearing 11 Compression chamber 12 Oldham ring 13 Lubricating oil 17 Lower bearing 18 Suction valve 18a Housing 18b Hole 18c Pin 18d Groove 18e Rotating shaft 18f, 22 Valve body 18g Taper 18h Dividing surface 18i Notch 19 Spring 20 Conventional suction valve 21 Suction port 23 Coil spring 24 Ring

Claims (10)

In a scroll compressor that is provided in a flow path for sucking refrigerant gas and includes a check valve that prevents reverse flow of the refrigerant gas, a turning scroll, and a fixed scroll,
The check valve is a valve body having a shape in which a plate is divided in two on a plane passing through the center, and is a valve that can be rotated around a rotation shaft provided on the surface side of each divided valve body. A scroll compressor having a body. In claim 1,
The flow path is configured by a casing press-fitted into the fixed scroll and a pipe press-fitted into the casing so as to sandwich the valve body between the casing and
Provided with a groove for holding the rotating shaft in the housing, and provided with a pin for rotatably holding the rotating shaft in the groove,
While avoiding the pin, provided a notch in the rotating shaft so that the end of the pin can be the center of rotation,
A scroll compressor characterized in that the valve body is rotatably held by inserting the rotating shaft into the groove. In claim 2,
A scroll compressor characterized in that a surface of the valve body on the housing side is tapered such that a thickness thereof decreases toward an outer peripheral side. In any one of Claims 1 thru | or 3,
A scroll compressor characterized in that when the check valve is open, the notch of the rotating shaft and the pin are in contact with each other. In any one of Claims 1 thru | or 3,
When the check valve is closed, an outer peripheral portion of the valve body is in contact with an end surface of the suction pipe, and the valve bodies are in contact with each other at a dividing surface. In any one of Claims 1 thru | or 4,
The scroll compressor is characterized in that the check valve is open when the pressure on the suction side and the discharge side of the scroll compressor is in an equilibrium state. In any one of Claims 1 thru | or 6,
A scroll compressor characterized in that the check valve is installed in a suction side pipe outside the scroll compressor. In claim 7,
A scroll compressor characterized in that when the check valve is open, the valve body hangs down in the direction of gravity. In any of claims 1 to 8,
A scroll compressor characterized in that the valve body is made of resin. In any one of Claims 1 thru | or 9,
The part that is in contact with the valve body and that is remote from the housing has a structure including an elastic body, and is movable while maintaining contact with the valve body in accordance with opening and closing of the check valve. A featured scroll compressor.

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