JP3027930B2 - Scroll gas compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an arrangement of a bypass valve of a scroll gas compressor.

[0002]

2. Description of the Related Art In a scroll gas compressor having low vibration and low noise characteristics, a suction chamber is provided at an outer peripheral portion of a spiral forming a compression space, a discharge port is provided at a central portion of the spiral, and a suction volume and a final volume are reduced. The compression ratio determined by the compression chamber volume is constant. In particular, when the fluctuation of the compression ratio determined by the suction pressure and the discharge pressure is small, a discharge valve for compressing a fluid such as a reciprocating compressor or a rotary compressor by setting a volume ratio corresponding to the fluctuation. Highly efficient compression is possible without the need for a device.

When this scroll gas compressor is used as a refrigerant compressor for air conditioning, the suction pressure and discharge pressure of the refrigerant change due to variable speed operation and fluctuations in air conditioning load. The difference between the actual compression ratio and the set compression ratio causes under-compression or over-compression operation. During insufficient compression, the high-pressure refrigerant gas in the discharge chamber intermittently flows back from the discharge port to the compression chamber,
This leads to an increase in compression input. In addition, when a so-called liquid compression phenomenon occurs in which a liquid refrigerant or a large amount of lubricating oil is compressed, an excessive compression state occurs, which may cause an abnormal increase in compression input, excessive vibration and noise, and damage to the compressor.

As a measure for preventing the backflow of the compressed fluid due to the insufficient compression, a check valve device may be provided at the outlet side of the discharge port. Further, as a measure to reduce over-compression, as described in Japanese Patent Publication No. 5-49830, when a compression chamber is provided which is always a closed space that does not intermittently communicate with both the suction chamber and the discharge port. The bypass valve device is provided with a bypass hole arranged at a symmetrical position communicating from the compression chamber, which is a normally closed space with a high frequency of excessive compression, to the discharge chamber, and allows only fluid outflow to the discharge chamber at the outlet side of the bypass hole. Means are provided to prevent compressor damage due to liquid compression or overcompression.

[0005]

However, in the above-described conventional configuration, the liquid compression or the normal over-compression that causes over-compression may not only occur in the above-mentioned constantly closed space but also in any compression chamber during compression. is there.

In particular, the refrigerant compressor for home air-conditioning has a small volume ratio, does not have the above-mentioned closed space, and is provided with a check valve device to prevent a backflow at the time of insufficient compression operation, and is caused by a change in air-conditioning load. In order to effectively prevent over-compression, means for opening a bypass hole in a compression chamber intermittently communicating with the discharge port has been studied.

In the case of this composite structure, there is a problem that the check valve device and the bypass valve interfere with each other because the discharge port and the bypass hole approach each other.

In order to solve this problem, it is necessary to reduce the amount of blocking of the check valve to the discharge port and the bypass valve to the bypass hole.

As a result, there has been a problem that the closing function of the check valve device and the bypass valve with respect to the discharge port and the bypass hole is reduced due to a positional shift when the check valve device and the bypass valve are respectively assembled to the fixed scroll. There is also a problem that the closing function of the bypass valve is reduced due to diffusion of the discharged gas when the check valve device opens and closes.

The present invention solves such a conventional problem, and improves the positioning accuracy when assembling the check valve device and the bypass valve to the fixed scroll to reduce the closing function of the check valve device and the bypass valve. The purpose is to prevent the occurrence of.

[0011]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a check valve device for opening and closing a discharge port, and a check valve for opening and closing a bypass hole formed in a compression chamber closest to the discharge port. A bypass valve close to the device is integrally connected. The bypass valve having a spring constant smaller than that of the check valve device and being easily deformed is connected to the check valve device having high rigidity so that there is no deviation from the bypass hole, and the function of closing the bypass hole can be enhanced.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a reed valve type in which fluid is allowed to flow only from a discharge port to a discharge chamber and the outlet side of the discharge port is opened and closed. The stop valve device is arranged on the end plate of the fixed scroll, and a pair of or more bypass holes which open to the compression chamber in the middle of compression closest to the discharge port and whose other end communicates with the discharge chamber are symmetrically arranged on the end plate, and through the bypass hole. A reed valve type bypass valve that allows fluid discharge only from the compression chamber to the discharge chamber and opens and closes the outlet side of the bypass hole is provided on the end plate close to the check valve device, and the spring constant of the bypass valve Is set smaller than the check valve device, and the bypass valve and the check valve device are integrally connected.

[0013] According to this configuration, the bypass valve supported by the check valve device having high rigidity closes the bypass hole without causing deformation and displacement, and exhibits a bypass effect. In addition, by shortening the time required for mounting the check valve device and the bypass valve, it is possible to provide working time for improving the mounting position accuracy of the check valve device and the bypass valve.

According to a second aspect of the present invention, the check valve device of the reed valve type and the bypass valve of the reed valve type are arranged in the same direction. According to this configuration, the check valve device and the bypass valve can be arranged and configured in a space-saving manner.

According to a third aspect of the present invention, there is provided a reed valve type check valve device which permits fluid flow only from the discharge port to the discharge chamber and opens and closes the outlet side of the discharge port on the end plate of the fixed scroll. A pair of at least one bypass hole that opens to the compression chamber in the middle of compression closest to the discharge port and the other end communicates with the discharge chamber is symmetrically arranged on the end plate, and fluid is discharged only from the compression chamber to the discharge chamber through the bypass hole. A configuration in which a reed valve type bypass valve that allows and opens and closes the outlet side of the bypass hole is provided on the end plate close to the check valve device, and the discharge valve seat of the check valve device is higher than the bypass valve seat of the bypass valve It is arranged.

According to this configuration, the function of diffusing the compressed gas flowing out of the discharge port does not cause the bypass valve to slightly float, and the function of closing the bypass hole can be continued.

According to a fourth aspect of the present invention, a plurality of bypass valves for opening and closing bypass holes arranged at symmetrical positions are integrally connected, and a plurality of bypass valves are formed so as to approach and surround a discharge valve seat of a check valve device. This is one in which a bypass valve is arranged. According to this configuration, the position of the bypass valve is regulated by the side wall of the discharge valve seat, and the displacement from the bypass hole can be eliminated.

According to a fifth aspect of the present invention, in a configuration in which a single bypass valve simultaneously opens and closes a plurality of bypass holes opened in the same compression chamber, both bypass valves having the same function mutually open and close the bypass holes simultaneously. For this reason, the spring constants of the two bypass valves are different.

According to this configuration, when the gas in the course of compression flows out through the bypass hole, the point of action of the gas pressure acting on each bypass valve is different, but the fully open timing of the bypass valve depends on the adjustment setting of the spring constant. Almost at the same time, 2
The pressure distribution in the two compression spaces can be the same.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A horizontal scroll gas compressor according to an embodiment of the present invention will be described below with reference to the drawings.

(Embodiment 1) In FIG. 1, reference numeral 1 denotes a closed container made of iron, the entire inside of which is a high-pressure atmosphere communicating with a discharge pipe (not shown), and a motor 3 is provided at the center and a compression section is provided at the right. A main body frame 5 of a compression unit that is arranged and supports one end of a drive shaft 4 to which a rotor 3a of the motor 3 is fixed is fixed to the closed casing 1, and a fixed scroll 7 is attached to the main body frame 5. One end of the main shaft direction oil hole 12 provided in the drive shaft 4 communicates with an oil supply pump device (not shown), and the other end finally communicates with the main bearing 8. The orbiting scroll 13 meshing with the fixed scroll 7 to form the compression chamber 2 is composed of a spiral orbiting scroll wrap 13a and a wrap supporting disk 13b with an orbiting shaft 13c standing upright.
And is located between.

Further, a spiral groove is provided at the tip of the orbiting scroll wrap 13a as disclosed in the aforementioned Japanese Utility Model Application Laid-Open No. 62-26591. A spiral seal member 13e having the same shape as the spiral groove is arranged in a loose state with a small gap in the spiral groove so that an oil film can be formed.

The fixed scroll 7 comprises a head plate 7a and a spiral fixed scroll wrap 7b. The fixed scroll wrap 7b has a discharge port 30 at the center and a suction chamber 3 at the outer periphery.
1 is arranged. The discharge port 30 is connected to the adjacent discharge chamber 3
2 leads to a high-pressure space in which the motor 3 is arranged. The suction chamber 31 communicates with a suction pipe 33 that penetrates the end wall of the closed container 1.

The orbiting bearing 14 eccentric from the main shaft of the drive shaft 4 and disposed in the right end hole of the drive shaft 4
3 and is configured to engage and slide with the turning shaft 13c. Between the lap support disk 13b of the orbiting scroll 13 and the thrust bearing 19 provided on the main body frame 5, there is provided a minute gap capable of forming an oil film.

An annular seal member 18 which is substantially concentric with the pivot shaft 13c is mounted on the lap support disk 13b in a loose state, and the annular seal member 18 is attached to the inner rear chamber A2.
It separates 0 from the outside. The upstream side and the downstream side of the rear chamber A20 communicate with the oil sump 11 via the sliding surface of the swing bearing 14, the oil hole 12 of the drive shaft 4, and the main bearing 8.

The space between the oil chamber 15 at the bottom of the slewing bearing 14 and the rear chamber C16 in the outer peripheral space of the lap support disk 13b is
It communicates through an oil passage 21 provided in the lap support disk 13b. The oil passage 21 has a narrowed portion A22 and a narrowed portion B23 at both ends thereof, and a bypass oil hole 24 in the middle. The bypass oil hole 24 is arranged to intermittently communicate with an annular oil groove 25 provided on the thrust bearing 19 surface in accordance with the turning movement of the turning scroll 13.

The annular oil groove 25 and the rear chamber C16 communicate with each other via a drain oil passage 26 provided as a part of the annular oil groove 25. Annular oil groove 25 of thrust bearing 19
Is arranged to intermittently communicate with a locking groove (not shown) of the orbiting scroll 13 which engages with the rotation preventing member 27. The rear chamber C16 and the suction chamber 31 communicate with each other via an oil groove 50 (see FIG. 2) provided on the surface of the end plate 7a which is in sliding contact with the lap support disk 13b.

A check valve device 35 for opening and closing the outlet side of the discharge port 30 is mounted on the plane of the end plate 7a of the fixed scroll 7, and the check valve device 35 includes a reed valve 35a made of a thin steel plate and a valve retainer. 35b. At the center of the end plate 7a, the second compression chamber 2b and the discharge chamber 32 that intermittently communicate with the discharge port 30 are opened, and the opening to the second compression chamber 2b is formed at the tip of the orbiting scroll wrap 13a. The bypass hole 39 having a smaller diameter than the width W of the seal member 13e disposed symmetrically with respect to the discharge port 30 is disposed.

The bypass holes 39 are composed of a pair of first bypass holes 39a and a pair of second bypass holes 39b, and are sequentially symmetrically arranged along the wall surface of the orbiting scroll wrap 13a so as to follow the progress of compression. First bypass hole 39
a, the second bypass holes 39b are arranged at appropriate intervals so as not to be completely closed at the same time by the seal member 13e.

A lead-type bypass valve 40 for opening and closing the outlet side of the pair of bypass holes 39 is attached to the end plate 7a. The bypass valve 40 includes a reed valve 40a made of a thin steel plate and a valve presser 40b, like the check valve device 35.

FIG. 2 is a cross-sectional view taken along the line AA in FIG. 1. The state of the compression space immediately after the second compression chamber 2b intermittently communicating with the discharge port 30 is opened with the discharge port 30. Is shown.

The volume ratio of the compression space, that is, the ratio between the suction volume of the compression chamber 2 and the volume of the compression chamber at the time of completion of compression, is determined by the pressure of the suction chamber 31 and the pressure of the discharge chamber 32 at the rated load of the compressor. It is set so as to be closest to the ratio, that is, the volume ratio corresponding to the operation compression ratio, and is set in a spiral compression space with little over / under compression during rated load operation.

In this state, the first bypass hole 39a and the second bypass hole 39a
The bypass hole 39b is arranged at a position that is not blocked by the orbiting scroll wrap 13a.

The first bypass hole 39a and the second bypass hole 39b can be simultaneously closed and closed by the orbiting scroll wrap 13a even when the second compression chamber 2b is advanced or retracted from the state shown in FIG. They are arranged with no shape and spacing.

A pair of auxiliary bypass holes 49 opened to the first compression chamber 2a and the discharge chamber 32 intermittently communicating with the suction chamber 31 are symmetrically arranged in the head plate 7a.
An auxiliary bypass valve device 42 for opening and closing the outlet side of the auxiliary bypass hole 49 is attached.

The auxiliary bypass valve device 42 comprises a reed valve 42a made of a thin steel plate and a valve retainer 42b.

As shown in FIG. 3, the check valve device 35, the bypass valve 40, and the auxiliary bypass valve device 42 are arranged in the same direction, are integrally connected, and are fixed to the end plate 7a by bolts.

Since the bypass hole 39 is arranged near the discharge port 30, the check valve device 35 and the bypass valve 40 are arranged close to each other. Since the pair of bypass valves 40 are arranged in the same direction, the pair of bypass valves 40
The second bypass hole 39b on the side close to the discharge port 30
And the point of action of the gas pressure discharged from the first bypass hole 39a distant from the discharge port 30 is interchanged.

Therefore, the spans 1 ₁ and 1 ₂ and the widths W ₁ and W ₂ of each reed valve 40a are changed so that the spring constants become almost the same so that the pair of bypass valves 40 can be fully opened almost at the same time. Have been. The spring constant of the bypass valve is set smaller than that of the check valve so that the bypass valve can be easily opened because the diameter of the bypass hole 39 is smaller than that of the discharge port 30.

FIG. 5 shows the compressor operating speed on the horizontal axis, and the pressure and compression ratio on the vertical axis, and shows the relationship between the compressor operating speed and the suction pressure, discharge pressure, and compression ratio when the air conditioner is operating. It is a characteristic diagram. FIG. 6 is a graph showing the change in the volume of the compression chamber on the horizontal axis and the change in pressure in the compression chamber on the vertical axis.
It is a V diagram (acupressure diagram).

The operation of the scroll gas compressor configured as described above will be described. 1 to 5, when the drive shaft 4 is rotationally driven by the motor 3, the orbiting scroll 13 supported by the thrust bearing 19 of the main body frame 5 orbits, and contains lubricating oil from a refrigeration cycle connected to the compressor. The suction refrigerant gas flows into the suction chamber 31 via the suction pipe 33, is compressed and transferred to the compression chamber 2 formed between the orbiting scroll 13 and the fixed scroll 7, and is discharged from the central discharge port 30, While being cooled through the chamber 32, the motor 3 is discharged to the outside of the compressor from a discharge pipe (not shown).

The discharge refrigerant gas containing the lubricating oil is supplied to the discharge chamber 3
2 is separated in the middle of the passage from the discharge pipe (not shown),
Collect in oil sump 11. The lubricating oil in the oil reservoir 11 to which the discharge pressure acts is sent to an oil chamber 15 via an oil hole 12 of the drive shaft 4 by an oil supply pump device (not shown) connected to one end of the drive shaft 4. Most of the lubricating oil returns to the oil sump 11 via the main bearing 8 while the remaining lubricating oil is
3 finally through the oil passage 21 provided in the rear chamber C
Flow into 16.

The lubricating oil flowing through the oil passage 21 is firstly depressurized at the throttle portion A22 at the inlet, and a part of the lubricating oil flows into the annular oil groove 25 provided in the thrust bearing 19 through the bypass oil hole 24. Then, the remaining lubricating oil is
After the secondary decompression in the lubricating oil passing through both paths,
Flows into the rear room C16 which leads to.

The lubricating oil in the oil passage 21 is supplied to the orbiting scroll 1
3, the bypass oil hole 24 is formed into an annular oil groove 2
5 intermittently communicates with the passage resistance. That is, when the turning speed is low, the lubricating oil in the oil passage 21 flows into the annular oil groove 25 more, and when the turning speed is high, the lubricating oil in the oil passage 21 flows into the annular oil groove 25 less. . The refrigerant gas pressure in the compression chamber 2 acts to move the orbiting scroll 13 away from the fixed scroll 7 in the main axis direction of the drive shaft 4.

On the other hand, the lap support disk 13b of the orbiting scroll 13 receives a back pressure from the back chamber A20 (the inner part surrounded by the annular seal member 18) where the discharge pressure acts. Therefore, the force for moving the orbiting scroll 13 away from the fixed scroll 7 and the back pressure are offset.

As a result, when the back pressure is larger than the repulsive force of the orbiting scroll 13, the lap support disk 13b is supported by the end plate 7a of the fixed scroll 7, and in the opposite case, the lap support disk 13b is supported by the thrust bearing 19. .

In any of the above cases, the lap support disk 1
A minute gap is maintained between the sliding surface 3b and the sliding surface, and an oil film is formed by the lubricating oil supplied to the sliding surface,
The sliding resistance is reduced.

The wrap support disk 13 of the orbiting scroll 13
b is the end plate 7a of the fixed scroll 7 or the thrust bearing 1
9, the gap between the compression chambers 2 is very small and is sealed by an oil film of the lubricating oil that has flowed into the compression chamber 2 through the rear chamber C16 and the suction chamber 31 in this order.

On the other hand, in the scroll gas compressor, since the compression ratio determined by the volume ratio and the characteristics of the refrigerant is constant, a large amount of refrigerant liquid flows into the compression chamber 2 at the beginning of the cold start of the compressor, and liquid compression occurs. In some cases, the pressure in the compression chamber 2 rises abnormally and becomes higher than the pressure in the discharge chamber 32. When liquid compression occurs in the first compression chamber 2a intermittently communicating with the suction chamber 31, the auxiliary bypass valve device 42 and the first bypass hole 39a for closing the outlet side of the auxiliary bypass hole 39a provided in the end plate 7a. ,
Bypass valve 4 for closing the outlet side of second bypass hole 39b
The 0 reed valves 40a are sequentially opened to allow the refrigerant to flow out to the discharge chamber 32, thereby lowering the compression chamber pressure.

Since the spring constant of the bypass valve 40 is set smaller than that of the check valve device 35, the bypass valve 40 is easily opened, and the bypass operation can be effectively performed.

Further, since the bypass valve 40 which is easily deformed is integrally connected to the check valve device 35,
The bypass hole 40 can be reliably closed without the bypass valve 40 being displaced from the bypass hole 39 at the time of assembling to the position a.

Further, a second communication port intermittently communicating with the discharge port 30 is provided.
When liquid compression occurs in the compression chamber 2b, the bypass valve 40 that closes the outlet side of the first bypass hole 39a and the second bypass hole 39b provided in the end plate 7a opens, causing the refrigerant to flow out to the discharge chamber 32, and compress the refrigerant. Reduce chamber pressure. In addition, the first and second
Since the bypass holes (39a, 39b) are arranged so as not to be simultaneously closed by the end faces of the orbiting scroll wrap 13a, the bypass valve 40 is always partially opened continuously.

The opening operation of the auxiliary bypass valve device 42 and the bypass valve 40 is not limited to the case where liquid compression occurs in the compression chamber 2.

That is, as shown in FIG. 4, the suction pressure in normal refrigeration cycle operation decreases as the compressor changes from low speed to high speed operation. On the other hand, the discharge pressure generally rises, and the compression ratio generally rises.

Therefore, when the auxiliary bypass valve device 42 and the bypass valve 40 are not installed, the compression ratio at the time of low-speed operation of the compressor is smaller than the compression ratio set in the rated load operation state, and the hatched portion in FIG. An over-compressed state is obtained as shown by.

In such a case, as described above, the reed valve 40a of the bypass valve 40 closing the outlet side of the first bypass hole 39a and the second bypass hole 39b opens to allow the refrigerant to flow out to the discharge chamber 32. As indicated by the two-dot chain line 99, the compression chamber pressure drops on the way, and the compression load is reduced.

Generally, the pressures of the compression chambers 2 (compression chambers A and B) arranged at symmetric positions are different from each other due to a difference in the degree of sealing of the compression chamber gap. The pressure difference in the compression chamber 2 applies a rotation force to the orbiting scroll 13 to apply a rotation force to the rotation prevention member 27.

However, when the auxiliary bypass valve device 42 and the bypass valve 40 are opened to reduce the compression load, the pressure in the compression chamber 2 (compression chamber A, compression chamber B) is increased through the discharge chamber 32 during the compression stroke. And the pressure is instantaneously equalized to reduce the compression chamber pressure difference.

When the first bypass hole 39a remote from the discharge port 30 is opened, the second bypass hole 39b closer to the discharge port 30 is also opened.
The bypass action from b operates smoothly and contributes to the reduction of input.

On the other hand, when the compressor operates at high speed, the pressure in the suction chamber 31 decreases and the pressure in the discharge chamber 32 increases. As a result, the actual compression ratio of the refrigeration cycle operation is larger than the set compression ratio of the scroll gas compressor. In this state, the bypass valve 40 does not open.

In this state, the refrigerant gas in the discharge chamber 32 is discharged from the discharge port 30 during the process of increasing the volume of the second compression chamber 2b and before the check valve device 35 closes the discharge port 30.
And intermittently flows back into the second compression chamber 2b. This backflow refrigerant gas is recompressed in the second compression chamber 2b, resulting in a compression loss.

However, when the lubricating oil supplied to the suction chamber 31 passes through the compression chamber together with the suctioned refrigerant gas, the oil film forms a gap between the adjacent compression chambers, the spiral groove, and the seal member 1.
Since the gap with 3e is sealed, backflow of the discharged refrigerant gas to the compression chamber that is not opened to the discharge port 30 is prevented.

The lubricating oil supplied to the compression chamber fills the bypass hole 39 having a diameter smaller than the width W of the seal member 13e,
The amount of refrigerant gas staying in the bypass hole 39 is small. As a result, the compression loss due to the re-expansion and re-compression of the refrigerant gas remaining in the bypass hole 39 is extremely small.

Further, the compressed refrigerant gas discharge passage immediately after the second compression chamber 2b opens to the discharge port 30 is narrow, and the opening of the check valve device 35 is delayed. Therefore, the discharge port 30
The pressure in the second compression chamber 2 b immediately after the opening is about to rise more than the discharge chamber 32.

However, a part of the compressed refrigerant gas is discharged to the bypass discharge chamber 36 through the bypass hole 39 and the bypass valve 40, and the pressure in the second compression chamber 2b decreases, so that excessive over-compression is avoided. , The compression input is reduced.

Thereafter, the compressed refrigerant gas is discharged from the discharge port 30 to the discharge chamber 32 as the opening between the second compression chamber 2b and the discharge port expands and the opening of the check valve device 35 advances.

Since the actual volume ratio (the ratio between the suction volume and the final compression chamber volume) is set in accordance with the rated operating load condition of the compressor, the opening position of the bypass hole 39 is significantly larger than the above-described position. In the case where the second compression chamber 2b is opened on the suction side, the orbiting scroll wrap 13a passes through the bypass hole 39, and the second compression chamber 2b moves to the discharge port 30 until the discharge chamber 30 is opened.

As a result, the substantial input reduction effect when over-compression occurs gradually decreases. Also, the bypass hole 39
When the opening position is closer to the discharge port 30 side than the above-described position, when the differential pressure between the suction pressure and the discharge pressure is large and the actual load compression ratio is larger than the set compression ratio, such as during high-speed operation of the compressor. In addition, the bypass hole 39 is blocked by the orbiting scroll wrap 13a before the second compression chamber 2b opens to the discharge port 30, so that the bypass effect is reduced.

It is no longer possible to avoid over-compression occurring immediately before and immediately after the second compression chamber 2b opens to the discharge port 30, and the input reduction effect by the bypass action is gradually reduced.

Although the size of the opening of the bypass hole 39 to the second compression chamber 2b is smaller than that of the seal member 13e in the above embodiment, it depends on the pressure load, the operating speed, the condition of the amount of oil supplied to the compression chamber, and the like. As a result, the width can be increased to the width W of the seal member 13e, and the formation of an oil film of the lubricating oil does not substantially reduce the compression efficiency.

[0071] and (Example 2) Figure 6 is the mounting surface of the check valve device 35 ₁ of the end plate 7a, the step between the mounting surface of the bypass valve 40 ₁ and the auxiliary bypass valve device 42 ₁ of the end plate 7a Provided. Check valve device 35 ₁ Discharge valve seat 35
c, the bypass valve 40 ₁ and the auxiliary bypass valve device 42
It is provided at a position higher than the _first bypass valve seat 40c. A pair of the bypass valve 40 ₁ and the auxiliary bypass valve device 42
₁ are arranged in the same direction and are integrally connected.

[0072] As in Example 1, a pair of the bypass valve 40 ₁ span (1 _1, 1 ₂₎ and the width (W _1, W ₂₎ are different from each other, different both of the bypass valve spring constant 4
0 ₁ is set to be fully open almost simultaneously.

[0073] a pair of the bypass valve 40 ₁ is a discharge valve seat 35c
Is arranged so as to be close to and surround the side wall. Bypass valve 40 ₁ is to increase the positioning accuracy during assembly, are set its shape.

[0074] In this configuration, the pressure at which the bypass valve 40 ₁ is the refrigerant gas flows out from the second compression chamber 2b by opening operation, the check valve device 35 ₁ started a little opening, the second compression chamber 2b Outflow of the discharged refrigerant gas after opening the discharge port 30 is smooth, and overcompression in the discharge port 30 can be reduced.

[0075] In a state where the bypass valve 40 ₁ is not opened operate, without being affected by air flow diffusion when the discharge refrigerant gas from the discharge port 30 flows out into the discharge chamber 32, the bypass valve 40 ₁ is a bypass hole 39 The compression efficiency can be prevented, and a decrease in compression efficiency due to the refrigerant gas in the discharge chamber 32 flowing back to the second compression chamber 2b via the bypass hole 39 can be prevented.

In the above embodiment, the discharge valve seat 35c and the end plate 7a are integrated, but may be formed separately.

[0077]

As is apparent from the above description, claim 1
According to the described invention, a reed valve type check valve device that permits fluid flow only from the discharge port to the discharge chamber and opens and closes the outlet side of the discharge port is disposed on the end plate of the fixed scroll, and the compression valve closest to the discharge port is provided. A pair of at least one bypass hole that opens to the compression chamber in the middle and the other end communicates with the discharge chamber is symmetrically arranged on the end plate, and allows the discharge of fluid only from the compression chamber to the discharge chamber through the bypass hole. A reed valve type bypass valve that opens and closes the outlet side is provided on the end plate close to the check valve device, and the spring constant of the bypass valve is set smaller than that of the check valve device. And are integrally connected.

According to this configuration, by shortening the time required for mounting the check valve device and the bypass valve, it is possible to provide working time for improving the mounting position accuracy of the check valve device and the bypass valve, and to provide a highly rigid check valve. The bypass valve supported by the device and having a small spring constant can be accurately assembled without causing a positional shift with respect to the bypass hole.

As a result, the backflow from the discharge chamber to the compression chamber via the bypass hole can be prevented, and the adverse effect due to the installation of the bypass valve can be prevented. In addition, since a bypass valve having a small spring constant can be easily arranged, an effective bypass action can be exhibited. Also, parts and assembly costs can be reduced.

According to the second aspect of the present invention, the reed valve type check valve device and the reed valve type bypass valve are arranged in the same direction.
The accuracy of assembling the bypass hole and the discharge port can be improved, and the mounting time can be shortened.

Further, since the direction of the metal structure of the material of the reed valve can be made to coincide with the longitudinal direction of the reed valve, the strength and reliability of the reed valve can be improved.

According to a third aspect of the present invention, a check valve device of a reed valve type that permits fluid flow only from the discharge port to the discharge chamber and opens and closes the outlet side of the discharge port is disposed on the end plate of the fixed scroll. A pair of at least one bypass hole that opens to the compression chamber in the middle of compression closest to the discharge port and the other end communicates with the discharge chamber is symmetrically arranged on the end plate, and fluid is discharged only from the compression chamber to the discharge chamber through the bypass hole. A configuration in which a reed valve type bypass valve that allows and opens and closes the outlet side of the bypass hole is provided on the end plate close to the check valve device, and the discharge valve seat of the check valve device is higher than the bypass valve seat of the bypass valve It is arranged.

According to this configuration, the function of closing the bypass hole can be continued without the bypass valve being minutely opened by the diffusion action of the compressed gas flow flowing out from the discharge port.

Further, the check valve device starts to open a little by the pressure when the gas flows out of the compression chamber during compression by the opening operation of the bypass valve to the discharge chamber, so that the compression chamber in the final stroke is connected to the discharge port. Outflow of discharge gas after opening is smooth,
Overcompression in the discharge port can be reduced.

According to a fourth aspect of the present invention, a plurality of bypass valves for opening and closing bypass holes arranged at symmetrical positions are integrally connected, and a plurality of bypass valves are provided so as to approach and surround a discharge valve seat of a check valve device. The bypass valve is arranged, and according to this configuration, the bypass valve can be accurately positioned by the side wall of the discharge valve seat, and the positional deviation between the bypass valve and the bypass hole can be eliminated.

As a result, an effective bypass function can be exerted without causing the adverse effect of installing the bypass valve.

According to a fifth aspect of the present invention, in a configuration in which a single bypass valve simultaneously opens and closes a plurality of bypass holes opened in the same compression chamber, both bypass valves having the same function as each other open and close the bypass holes simultaneously. For this reason, the spring constants of the two bypass valves are different.

According to this configuration, even when the point of action of the gas pressure acting on each bypass valve is different when the gas during compression flows out to the discharge chamber through the bypass hole, the bypass valve is adjusted by setting the spring constant. Full opening can be performed almost simultaneously.

Further, it is possible to prevent the adverse effect when the pair of bypass valves are arranged in the same direction and connected integrally (an increase in the compression torque fluctuation due to the occurrence of the difference in the pressure distribution in the symmetrical compression space).

[Brief description of the drawings]

FIG. 1 is a partial longitudinal sectional view of one embodiment of a scroll gas compressor of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a layout diagram of a check valve device and a bypass valve.

FIG. 4 is a characteristic diagram showing a relationship between compressor operating speed and pressure.

FIG. 5 is a characteristic diagram showing a change in volume and a change in pressure of a compression chamber.

FIG. 6 is a partial longitudinal sectional view of another embodiment of the scroll gas compressor of the present invention.

FIG. 7 is a layout view of a check valve device and a bypass valve according to another embodiment.

[Explanation of symbols]

 2 Compression chamber 4 Drive shaft 5 Body frame 7 Fixed scroll 7a End plate 7b Fixed scroll wrap 13 Orbiting scroll 13a Orbiting scroll wrap 13b Lapping support disk 19 Thrust bearing 30 Discharge port 31 Suction chamber 32 Discharge chamber 35 Check valve device 35c Discharge valve Seat 39 Bypass hole 40 Bypass valve 40c Bypass valve seat

──────────────────────────────────────────────────の Continuing on the front page (72) Shozo Hase, 1006 Kadoma Kadoma, Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Hiromasa Ashiya 1006 Kadoma, Kadoma, Kadoma, Osaka Matsushita Electric Industrial Co., Ltd. (72) Inventor Shuichi Yamamoto 1006 Kadoma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Inventor Kiyoshi Sawai 1006 Odaka Kadoma, Kadoma City, Osaka Pref. Matsushita Electric Industrial Co., Ltd. (58) Field (Int. Cl. ⁷ , DB name) F04C 18/02 311 F04C 29/00 F04C 29/10 331

Claims (5)

(57) [Claims] 1. A fixed scroll wrap, which is formed upright on one surface of a mirror plate forming a part of a fixed scroll, stands upright on a wrap supporting disk forming a part of a revolving scroll and is fixed. Orbiting scroll wraps similar in shape to the scroll wraps are meshed with each other to form a pair of spiral compression spaces between the two scrolls, and a discharge port communicating with a discharge chamber is provided in the center of the fixed scroll wrap, and the fixed scroll wrap is provided. A suction chamber is provided outside the scroll wrap to prevent rotation of the orbiting scroll, which engages with the wrap support disk engaged with the drive shaft and the main frame that fastens the fixed scroll and supports the drive shaft. The orbiting scroll makes a revolving motion with respect to the fixed scroll via a member, whereby each compression space is directed from the suction side to the discharge side. A scroll compression mechanism that is divided into a plurality of compression chambers that continuously move and that changes volume to compress fluid, and that oil is supplied from an oil reservoir to which discharge pressure acts to at least one of the compression chamber and the suction chamber. A passage is formed, and the anti-compression space side of the lap support disc is supported by a thrust bearing provided on the main body frame, and the orbiting scroll is back-biased toward the fixed scroll. A reed valve type check valve device that allows fluid flow only from the discharge port to the discharge chamber and opens and closes the outlet side of the discharge port is disposed on the end plate, and the discharge port is A pair of at least one bypass hole that opens to the compression chamber in the middle of the closest compression and the other end communicates with the discharge chamber is symmetrically arranged on the end plate, and the compression chamber is connected to the discharge chamber through the bypass hole. A reed valve-type bypass valve for allowing fluid discharge and opening and closing the outlet side of the bypass hole is provided on the end plate close to the check valve device, and the spring constant of the bypass valve is set to the check. A scroll gas compressor set smaller than a valve device and integrally connecting the bypass valve and the check valve device. 2. The scroll gas compressor according to claim 1, wherein the check valve device and the bypass valve are arranged in the same direction. 3. A fixed scroll wrap, which is formed upright on one surface of a mirror plate forming a part of a fixed scroll, and stands upright on a wrap supporting disk forming a part of an orbiting scroll and is fixed. The orbiting scroll wraps having a shape similar to the scroll wrap are engaged with each other to form a pair of spiral compression spaces between the two scrolls, and a discharge port communicating with a discharge chamber is provided at the center of the fixed scroll wrap, and the fixed scroll wrap is provided. A suction chamber is provided outside the scroll wrap to prevent rotation of the orbiting scroll, which engages with the wrap support disk engaged with the drive shaft and the main frame that fastens the fixed scroll and supports the drive shaft. The orbiting scroll makes a revolving motion with respect to the fixed scroll via a member, whereby each compression space is directed from the suction side to the discharge side. A scroll compression mechanism that is divided into a plurality of compression chambers that continuously move and that changes volume to compress fluid, and that oil is supplied from an oil reservoir to which discharge pressure acts to at least one of the compression chamber and the suction chamber. A passage is formed, and the anti-compression space side of the lap support disc is supported by a thrust bearing provided on the main body frame, and the orbiting scroll is back-biased toward the fixed scroll. A reed valve type check valve device that allows fluid flow only from the discharge port to the discharge chamber and opens and closes the outlet side of the discharge port is disposed on the end plate, and the discharge port is A pair of at least one bypass hole that opens to the compression chamber in the middle of the closest compression and the other end communicates with the discharge chamber is symmetrically arranged on the end plate, and the compression chamber is connected to the discharge chamber through the bypass hole. A discharge valve seat of the check valve device is provided, wherein a reed valve type bypass valve for allowing fluid discharge and opening / closing the outlet side of the bypass hole is provided on the end plate close to the check valve device. A scroll gas compressor disposed higher than a bypass valve seat of the bypass valve. 4. A plurality of bypass valves for opening and closing a bypass hole arranged in a symmetrical position are integrally connected, and the plurality of bypass valves are arranged so as to be close to and surround a discharge valve seat of a check valve device. The scroll gas compressor according to claim 3. 5. A configuration in which a single bypass valve simultaneously opens and closes a plurality of bypass holes opened in the same compression chamber,
The scroll gas compressor according to any one of claims 2 to 4, wherein both bypass valves having the same function mutually open and close the bypass hole at the same time, and have different spring constants of the two bypass valves.