JPH09217689A - Scroll gas compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To materialize valve constitution for prevention of positional slippage and interference at the time of assembling and arranging a check valve system and a by-pass valve close to each other. SOLUTION: It is constituted by symmetrically arranging more than one pair of by-pass holes 39 a, b communicating a compression chamber 2b nearest to a delivery port 30 and a delivery chamber 32 to each other on an end plate 7a of a fixed scroll 7 and providing a check valve system 35 to open and close the delivery port 30 and a by-pass valve 40 to open and close the by-pass holes 39 a, b on the end plate 7a close to each other, a spring constant of the by-pass valve 40 is set smaller than the check valve system 35, and the by-pass valve 40 and the check valve system 35 are integrally connected to each other. In this constitution, it is possible to precisely assemble the by-pass valve 40 supported by the check valve system 35 of high rigidity and having the small spring constant without causing positional slippage against the by-pass holes 39 a, b, and accordingly, it is possible to prevent back-flow from the delivery chamber 32 to the compression chamber 2b through the by-pass holes.

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 A scroll gas compressor having low vibration and low noise characteristics has a suction chamber at the outer periphery of a spiral forming a compression space, a discharge port provided at the center of the spiral, and a suction volume and a final volume. The compression ratio determined by the compression chamber volume is constant. In particular, when there is little fluctuation in the compression ratio determined by the suction pressure and the discharge pressure, a discharge valve for compressing fluid such as a reciprocating compressor or a rotary compressor is set by setting a volume ratio that matches it. Highly efficient compression is possible without requiring a device.

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

A check valve device may be provided on the outlet side of the discharge port as a measure for preventing the backflow of the compressed fluid due to such insufficient compression. Further, as a measure for reducing overcompression, as described in Japanese Patent Publication No. 5-49830, in the case where a compression chamber that is a constantly closed space that does not intermittently communicate with either the suction chamber or the discharge port is provided, A bypass valve device is provided at a symmetrical position that leads from the compression chamber, which is a normally closed space with a high frequency of excessive compression, to the discharge chamber, and a bypass valve device that allows only the outflow of fluid to the discharge chamber on the outlet side of the bypass hole. There are known means for preventing damage to the compressor due to liquid compression or overcompression.

[0005]

However, in the above-mentioned conventional structure, the liquid compression which is the over-compression and the normal over-compression may occur not only in the above-mentioned always closed space but also in any compression chamber during the compression. is there.

[0006] In particular, a home air-conditioning refrigerant compressor has a small volume ratio, does not have the above-mentioned closed space at all times, and is provided with a check valve device to prevent backflow at the time of insufficient compression operation and to be caused by fluctuation of air conditioning load. In order to effectively act to prevent overcompression, 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 are close to each other.

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

As a result, there is 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 deteriorates due to the positional deviation when the check valve device and the bypass valve are assembled to the fixed scroll. There is also a problem that the closing function of the bypass valve deteriorates due to the 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 the check valve device and the bypass valve are assembled to the fixed scroll to reduce the closing function of the check valve device and the bypass valve. The purpose is to prevent

[0011]

In order to solve the above problems, the present invention relates to a check valve device for opening and closing a discharge port, and a check valve for opening and closing a bypass hole opened in a compression chamber closest to the discharge port. The bypass valve close to the device is integrally connected. The bypass valve, which has a spring constant smaller than that of the check valve device and is easily deformed, is connected to the check valve device having high rigidity so that the deviation from the bypass hole is eliminated and the function of closing the bypass hole can be enhanced.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 for solving the above-mentioned problems is a reed valve type reverse type which allows a fluid flow only from the discharge port to the discharge chamber and opens and closes the outlet side of the discharge port. The stop valve device is arranged on the end plate of the fixed scroll, and a pair of bypass holes, which open to the compression chamber closest to the discharge port in the middle of compression and whose other end communicates with the discharge chamber, are symmetrically arranged on the end plate and through the bypass hole. The reed valve type bypass valve that allows fluid to be discharged only from the compression chamber to the discharge chamber and opens and closes the outlet side of the bypass hole is installed on the end plate near the check valve device. Is set smaller than the check valve device, and the bypass valve and the check valve device are integrally connected.

Further, according to this structure, the bypass valve supported by the check valve device having high rigidity closes the bypass hole without causing deformation and displacement, and exerts a bypass action. Further, by shortening the mounting time of the check valve device and the bypass valve, it is possible to add working time to improve the mounting position accuracy of the check valve device and the bypass valve.

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

According to a third aspect of the present invention, 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 arranged on the end plate of the fixed scroll. A pair of bypass holes, which open to the compression chamber closest to the discharge port and which communicate with the discharge chamber at the other end, are symmetrically arranged on the end plate, and the fluid is discharged only from the compression chamber to the discharge chamber through the bypass hole. 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 structure, the bypass valve can continue to function to be closed without the bypass valve slightly floating due to the diffusion action of the compressed gas flow flowing out from the discharge port.

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 surround the discharge valve seat of the check valve device. The bypass valve is arranged. Further, according to this structure, the side wall of the discharge valve seat regulates the position of the bypass valve, so that the positional deviation from the bypass hole can be eliminated.

In 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 simultaneously open and close the bypass holes. Therefore, the spring constants of both bypass valves are made different.

According to this structure, when the gas during compression flows out through the bypass hole, the point of action of the gas pressure acting on each bypass valve is different, but the timing of full opening 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]

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 is an iron-made hermetic container, the entire interior of which is a high-pressure atmosphere communicating with a discharge pipe (not shown), in which a motor 3 is provided at the center and a compression portion is provided at the right. A main body frame 5 of a compression section, which is arranged and supports one end of a drive shaft 4 to which the rotor 3a of the motor 3 is fixed, is fixed to the closed container 1, and a fixed scroll 7 is attached to the main body frame 5. The main shaft direction oil hole 12 provided in the drive shaft 4 has one end communicating with an oil supply pump device (not shown) and the other end finally communicating with the main bearing 8. The orbiting scroll 13 that meshes with the fixed scroll 7 to form the compression chamber 2 comprises a spiral orbiting scroll wrap 13a and a wrap support disk 13b in which an orbiting shaft 13c is upright, and the fixed scroll 7 and the main body frame 5 are provided.
It is located between and.

A spiral groove as disclosed in Japanese Utility Model Laid-Open No. 62-26591 is provided at the tip of the orbiting scroll wrap 13a. A spiral seal member 13e having the same shape as the spiral groove is arranged in a loose state with a minute gap enough to form an oil film in the spiral groove.

The fixed scroll 7 comprises an end plate 7a and a spiral fixed scroll wrap 7b. The fixed scroll wrap 7b has a discharge port 30 at the center and an intake chamber 3 at the outer peripheral portion.
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 disposed in the right end hole of the drive shaft 4 eccentrically from the main shaft of the drive shaft 4 has an orbiting scroll 1.
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 swivel shaft 13c is mounted on the lap support disk 13b in a loosely fitted state, and the annular seal member 18 is located inside the rear chamber A2.
It divides 0 and the outside. The upstream side and the downstream side of the back chamber A20 communicate with the oil reservoir 11 via the sliding surface of the orbiting bearing 14, the oil hole 12 of the drive shaft 4 and the main bearing 8.

Between the oil chamber 15 at the bottom of the slewing bearing 14 and the back chamber C16 in the outer peripheral space of the lap support disk 13b,
It communicates via an oil passage 21 provided in the lap support disk 13b. The oil passage 21 has a throttle portion A22 and a throttle portion B23 at both ends thereof, and a bypass oil hole 24 in the middle thereof. The bypass oil hole 24 is arranged so as to intermittently communicate with an annular oil groove 25 provided on the surface of the thrust bearing 19 as the orbiting scroll 13 orbits.

The annular oil groove 25 and the back chamber C16 communicate with each other through a discharge oil passage 26 provided as a part of the annular oil groove 25. Annular oil groove 25 of thrust bearing 19
Are arranged to intermittently communicate with a locking groove (not shown) of the orbiting scroll 13 that engages with the rotation preventing member 27. The back chamber C16 and the suction chamber 31 are communicated with each other via an oil groove 50 (see FIG. 2) provided on the surface of the end plate 7a that 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 flat surface of the end plate 7a of the fixed scroll 7, and the check valve device 35 is made of a thin steel plate reed valve 35a and a valve retainer. 35b. At the center of the end plate 7a, the second compression chamber 2b and the discharge chamber 32, which intermittently communicate with the discharge port 30, are opened, and the opening to the second compression chamber 2b is provided at the tip of the orbiting scroll wrap 13a. Bypass holes 39 having a diameter smaller than the width W of the seal member 13e arranged at are disposed symmetrically with respect to the discharge port 30.

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
The a and the second bypass holes 39b are arranged at proper intervals so that they are not completely blocked by the seal member 13e at the same time.

A reed 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 is composed of a thin steel plate reed valve 40a and a valve retainer 40b, like the check valve device 35.

FIG. 2 is a view showing a cross section taken along the line AA in FIG. 1, showing a state of the compression space immediately after the second compression chamber 2b which is intermittently communicated with the discharge port 30 is opened with the discharge port 30. Indicates.

The volume ratio of the compression space, that is, the ratio between the suction volume of the compression chamber 2 and the compression chamber volume at the completion of compression is the pressure of the suction chamber 31 and the pressure of the discharge chamber 32 at the rated load of the compressor. The ratio, that is, the volume ratio corresponding to the operation compression ratio, is set to be closest to the volume ratio, and is set to a spiral-shaped compression space with less excess and deficient 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 where it is not blocked by the orbiting scroll wrap 13a.

Further, the first bypass hole 39a and the second bypass hole 39b can be simultaneously blocked by the orbiting scroll wrap 13a even when the second compression chamber 2b is advanced or retreated from the state of FIG. They are arranged so that they do not exist.

Further, the end plate 7a is provided with a pair of auxiliary bypass holes 49 which are opened symmetrically with respect to the first compression chamber 2a and the discharge chamber 32, which are intermittently connected to the suction chamber 31, and are symmetrically arranged.
An auxiliary bypass valve device 42 that opens and closes the outlet side of the auxiliary bypass hole 49 is attached.

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

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, integrally connected, and 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 closer to the discharge port 30
And the action points of the gas pressure discharged from the first bypass hole 39a separated from the discharge port 30 are exchanged with each other.

Therefore, the spans 1 ₁ and 1 ₂ and the widths W ₁ and W ₂ of the reed valves 40a are changed so that the spring constants are substantially the same so that the pair of bypass valves 40 can be fully opened at substantially the same time. Has been done. Since the bypass hole 39 has a smaller diameter than the discharge port 30, 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.

In FIG. 5, the horizontal axis represents the compressor operating speed and the vertical axis represents the pressure and the compression ratio, and the actual load showing the relationship between the compressor operating speed and the suction pressure, the discharge pressure, and the compression ratio when the air conditioner is operating. It is a characteristic diagram. In FIG. 6, the horizontal axis represents the volume change of the compression chamber, and the vertical axis represents the pressure change of the compression chamber.
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 makes an orbiting motion and contains lubricating oil from the 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 at the central discharge port 30. While cooling the motor 3 through the chamber 32, it is discharged from the compressor through a discharge pipe (not shown).

The discharge refrigerant gas containing lubricating oil is discharged into 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 sump 11 on which the discharge pressure acts is sent to the oil chamber 15 via the 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 oil returns to the oil sump 11 via the main bearing 8, while the remaining lubricating oil is used for the orbiting scroll 1.
3 through the oil passage 21 provided at the end of the rear chamber C
It flows into 16.

The lubricating oil flowing through the oil passage 21 is primarily depressurized by the throttle portion A22 at the inlet thereof, 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. However, the remaining lubricating oil is the throttle B23.
After the secondary depressurization in
Flows into the back chamber C16 leading to.

Lubricating oil in the oil passage 21 is used for the orbiting scroll 1.
3, the bypass oil hole 24 is formed into an annular oil groove 2
5 is affected by the passage resistance at the time of intermittent communication. That is, when the turning speed is slow, a large amount of the lubricating oil in the oil passage 21 flows into the annular oil groove 25, and when the turning speed is fast, a small amount of the lubricating oil in the oil passage 21 flows into the annular oil groove 25. . 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 the back pressure from the back chamber A20 (the inner portion surrounded by the annular seal member 18) on which the discharge pressure acts. Therefore, the force for separating the orbiting scroll 13 from the fixed scroll 7 and the back pressure cancel each other out.

As a result, when the back pressure is larger than the separating 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, by the thrust bearing 19. .

In any of the above cases, the lap support disc 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.

Lap support disk 13 of orbiting scroll 13
b is the end plate 7a of the fixed scroll 7 or the thrust bearing 1
In any case, the compression chamber 2 has a very small gap and is sealed with an oil film of the lubricating oil that has flowed into the compression chamber 2 through the back chamber C16 and the suction chamber 31 in sequence.

On the other hand, since the scroll gas compressor has a constant compression ratio determined by the volume ratio and the characteristics of the refrigerant, a large amount of refrigerant liquid flows into the compression chamber 2 in the early stage of starting the compressor when the compressor is cold, 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 which communicates intermittently with the suction chamber 31, the auxiliary bypass valve device 42 and the first bypass hole 39a which close the outlet side of the auxiliary bypass hole 39a provided in the end plate 7a. ，
Bypass valve 4 for closing the outlet side of the second bypass hole 39b
The reed valve 40a of 0 is sequentially opened to allow the refrigerant to flow into the discharge chamber 32, thereby reducing the pressure in the compression chamber.

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 action can be effectively performed.

Further, since it is integrally connected to the check valve device 35, the bypass valve 40 having an easily deformable shape is installed in the end plate 7.
The bypass valve 40 does not shift from the bypass hole 39 when it is assembled to a, and the bypass hole 39 can be reliably closed.

In addition, the second which intermittently communicates with the discharge port 30
When liquid compression occurs in the compression chamber 2b, the bypass valve 40, which closes the outlet side of the first bypass hole 39a and the second bypass hole 39b provided in the end plate 7a, opens to allow the refrigerant to flow into the discharge chamber 32, thereby compressing the refrigerant. Reduce the chamber pressure. The first and second
Since the bypass holes (39a, 39b) are arranged so as not to be closed at the same time by the end surface of the orbiting scroll wrap 13a, the bypass valve 40 is always partially continuously opened.

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 the 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. As shown by, it becomes an over-compressed state.

In this case, the reed valve 40a of the bypass valve 40 that closes the outlet sides of the first bypass hole 39a and the second bypass hole 39b is opened to let the refrigerant flow into the discharge chamber 32, as described above. As indicated by the chain double-dashed line 99, the compression chamber pressure drops midway and the compression load is reduced.

Generally, the respective pressures of the compression chambers 2 (compression chamber A, compression chamber B) arranged symmetrically differ from each other due to the difference in the degree of compression chamber clearance sealing. The pressure difference in the compression chamber 2 gives a rotation force to the orbiting scroll 13 to give 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 of the compression chamber 2 (compression chamber A, compression chamber B) is discharged through the discharge chamber 32 during the compression stroke. Then, the pressure is instantly equalized and the pressure difference in the compression chamber is reduced.

Further, since the first bypass hole 39a separated from the discharge port 30 is opened, the second bypass hole 39b on the side closer to the discharge port 30 is also opened, so that the second compression chamber 2 is opened.
The bypass action from b operates smoothly and contributes to input reduction.

On the other hand, during high-speed operation of the compressor, the pressure in the suction chamber 31 drops and the pressure in the discharge chamber 32 rises. As a result, the actual refrigeration cycle operation compression ratio is larger than the scroll gas compressor set compression ratio. The bypass valve 40 is in a non-opening state).

In this state, the refrigerant gas in the discharge chamber 32 is discharged from the discharge port 30 while the capacity of the second compression chamber 2b is being expanded and before the check valve device 35 closes the discharge port 30.
And intermittently flows back to the second compression chamber 2b via. This backflow refrigerant gas is recompressed in the second compression chamber 2b and becomes a compression loss.

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

Further, 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 accumulated in the bypass hole 39 is small. As a result, the compression loss due to 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 is opened to the discharge port 30 is narrow, and the opening of the check valve device 35 is delayed. Therefore, the discharge port 30
Further, the pressure in the second compression chamber 2b immediately after the opening is about to rise above the discharge chamber 32.

However, a part of the compressed refrigerant gas is discharged into the bypass discharge chamber 36 through the bypass hole 39 and the bypass valve 40, the pressure in the second compression chamber 2b decreases, and excessive overcompression 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 communication between the second compression chamber 2b and the discharge port is enlarged and the check valve device 35 is opened.

Since the actual volume ratio (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 position. When it is opened on the suction side, it becomes a closed space in the compression chamber movement range until the second compression chamber 2b after the orbiting scroll wrap 13a has passed through the bypass hole 39 and the second compression chamber 2b is opened to the discharge port 30.

As a result, the substantial input reduction effect at the time of occurrence of overcompression gradually decreases. Also, the bypass hole 39
When the opening position of is closer to the discharge port 30 side than the above 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, since the bypass hole 39 is shielded by the orbiting scroll wrap 13a before the second compression chamber 2b is opened to the discharge port 30, the bypass action is reduced.

It becomes impossible to avoid overcompression occurring immediately before and after the second compression chamber 2b opens with the discharge port 30, and the input reduction effect due to the bypass action gradually decreases.

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 may be changed depending on the pressure load, the operating speed, the amount of oil supplied to the compression chamber, and the like. Thus, the width W of the seal member 13e can be widened, and the compression efficiency is not substantially reduced due to the formation of the lubricating oil film.

(Embodiment 2) FIG. 6 shows a step between the mounting surface of the check valve device 35 _{1 on} the end plate 7a and the mounting surface of the bypass valve 40 ₁ and the auxiliary bypass valve device 42 _{1 on} the end plate 7a. It is provided. Discharge valve seat 35 of check valve device 35 _1.
c is a bypass valve 40 ₁ and an auxiliary bypass valve device 42
It is provided at a position higher than the _first bypass valve seat 40c. A pair of bypass valves 40 ₁ and auxiliary bypass valve device 42
₁ is integrally connected are arranged in the same direction.

As in the case of the first embodiment, both bypass valves 40 ₁ having different spring constants have different spans (1 ₁ , 1 ₂ ) and widths (W ₁ , W ₂ ). Four
0 ₁ is set to be fully opened almost at the same time.

The pair of bypass valves 40 ₁ is the discharge valve seat 35c.
It is arranged so as to surround and close to the side wall. The shape of the bypass valve 40 ₁ is set so as to improve the positioning accuracy during assembly.

In this structure, the check valve device 35 ₁ starts to open slightly due to the pressure when the bypass valve 40 ₁ is opened and the refrigerant gas flows out from the second compression chamber 2b, and the second compression chamber 2b is opened. Outflow of the discharge refrigerant gas after opening the discharge port 30 becomes smooth, and overcompression in the discharge port 30 can be reduced.

Further, in a state where the bypass valve 40 ₁ is not opened, the bypass valve 40 ₁ is provided with the bypass hole 39 without being affected by the air flow diffusion when the discharge refrigerant gas flows from the discharge port 30 into the discharge chamber 32. It can be closed, and it is possible to prevent a reduction 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.

Although the discharge valve seat 35c and the end plate 7a are integrally formed in the above embodiment, they may be separately formed.

[0077]

As is apparent from the above description, claim 1
In the invention described, 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 arranged on the end plate of the fixed scroll, and the compression closest to the discharge port is performed. A pair of bypass holes, which open to the compression chamber on the way and open at the other end to the discharge chamber, are symmetrically arranged on the end plate, and allow 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 installed 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 structure, by shortening the mounting time of the check valve device and the bypass valve, the working time can be given to improve the mounting position accuracy of the check valve device and the bypass valve, and the check valve having high rigidity can be provided. The bypass valve supported by the device and having a small spring constant can be assembled with high accuracy without causing positional deviation with respect to the bypass hole.

As a result, it is possible to prevent the backflow from the discharge chamber to the compression chamber via the bypass hole, and to prevent the adverse effect of installing the bypass valve. In addition, since a bypass valve having a small spring constant can be easily arranged, an effective bypass action can be exerted. In addition, 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. According to this configuration, the parts can be easily handled.
Assembling accuracy with respect to 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 provided in 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 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 arranged on the end plate of the fixed scroll. A pair of bypass holes, which open to the compression chamber closest to the discharge port and which communicate with the discharge chamber at the other end, are symmetrically arranged on the end plate, and the fluid is discharged only from the compression chamber to the discharge chamber through the bypass hole. 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 structure, the bypass valve can be kept closed without the minute opening of the bypass valve due to the diffusion action of the compressed gas flow flowing out from the discharge port.

Further, the check valve device starts to open a little due to the pressure when the bypass valve is opened and the gas flows from the compression chamber in the middle of compression to the discharge chamber. Outflow of discharged gas after opening becomes smooth,
Overcompression in the discharge port can be reduced.

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

As a result, an effective bypass function can be operated without causing any 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 simultaneously open and close the bypass holes. Therefore, the spring constants of both bypass valves are made different.

According to this structure, when the gas on the way of compression flows into the discharge chamber through the bypass hole, even if the point of action of the gas pressure acting on each bypass valve is different, the bypass valve can be adjusted by adjusting the spring constant. Full opening can act almost simultaneously.

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

[Brief description of drawings]

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

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

Fig. 3 Layout of check valve device and bypass valve

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

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

FIG. 6 is a partial vertical cross-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 lap support disc 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

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shozo Hase 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Hiromasa Ashiya 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. 72) Inventor Shuichi Yamamoto 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) In Kiyoshi Sawai, 1006 Kadoma, Kadoma City Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (5)

[Claims] 1. A spiral fixed scroll wrap which is formed upright on one surface of a mirror plate which forms a part of a fixed scroll, and which is upright and fixed on a wrap support disk which forms a part of an orbiting scroll. Orbiting scroll wraps similar in shape to scroll wraps are meshed with each other to form a pair of spiral compression spaces between the scrolls, and a discharge port communicating with a discharge chamber is provided in the center of the fixed scroll wrap, and the fixed scroll is fixed. A suction chamber is provided outside the scroll wrap to prevent rotation of the orbiting scroll that engages with the wrap support disc that engages with the drive shaft and the body frame that fastens the fixed scroll and supports the drive shaft. When the orbiting scroll revolves with respect to the fixed scroll through the member, the compression spaces are directed from the suction side to the discharge side. And a scroll compression mechanism that is divided into a plurality of compression chambers that continuously move to change the volume so as to compress the fluid, and oil supply from an oil reservoir on which the discharge pressure acts to at least one of the compression chamber and the suction chamber. And a shape in which the anti-compression space side of the lap support disk is supported by a thrust bearing provided in the main body frame, and a shape in which the orbiting scroll is biased by the back pressure toward the fixed scroll. At least one of them, 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 arranged on the end plate, A pair of bypass holes that open to the nearest compression chamber and have the other end communicating with the discharge chamber are symmetrically arranged on the end plate, and the compression chamber to the discharge chamber passes through the bypass hole. A reed valve type bypass valve that allows the fluid discharge of the bypass valve 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 to the check valve. A scroll gas compressor which is set smaller than a valve device and integrally connects 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 spiral fixed scroll wrap which is formed upright on one surface of a mirror plate which is a part of a fixed scroll, and which is upright and fixed on a wrap support disk which is a part of an orbiting scroll. Orbiting scroll wraps similar in shape to scroll wraps are meshed with each other to form a pair of spiral compression spaces between the scrolls, and a discharge port communicating with a discharge chamber is provided in the center of the fixed scroll wrap, and the fixed scroll is fixed. A suction chamber is provided outside the scroll wrap to prevent rotation of the orbiting scroll that engages with the wrap support disc that engages with the drive shaft and the body frame that fastens the fixed scroll and supports the drive shaft. When the orbiting scroll revolves with respect to the fixed scroll through the member, the compression spaces are directed from the suction side to the discharge side. And a scroll compression mechanism that is divided into a plurality of compression chambers that continuously move to change the volume so as to compress the fluid, and oil supply from an oil reservoir on which the discharge pressure acts to at least one of the compression chamber and the suction chamber. And a shape in which the anti-compression space side of the lap support disk is supported by a thrust bearing provided in the main body frame, and a shape in which the orbiting scroll is biased by the back pressure toward the fixed scroll. At least one of them, 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 arranged on the end plate, A pair of bypass holes that open to the nearest compression chamber and have the other end communicating with the discharge chamber are symmetrically arranged on the end plate, and the compression chamber to the discharge chamber passes through the bypass hole. A reed valve type bypass valve that allows the fluid discharge of the above 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 provided. A scroll gas compressor arranged higher than the bypass valve seat of the bypass valve. 4. A plurality of bypass valves for opening and closing bypass holes arranged at symmetrical positions are integrally connected, and the plurality of bypass valves are arranged so as to surround the discharge valve seat of the check valve device and surround it. 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 spring constants of both bypass valves are different so that both bypass valves having the same function open and close the bypass hole at the same time.