JP6946111B2 - Scroll compressor - Google Patents

Description

The present invention relates to a scroll compressor provided with a bypass valve.

The end plate of the fixed scroll of the scroll compressor is provided with a discharge port for discharging the compressed fluid and a bypass port for discharging the fluid in the middle of compression to prevent overcompression and liquid compression. A plurality of pairs of bypass ports may be provided with the discharge port in between. In this case, it becomes difficult to arrange the discharge valve that closes the discharge port and the plurality of bypass valves that block each bypass port without interfering with each other.
On the other hand, in Patent Document 1, a recess is formed in the end plate of the fixed scroll on which the discharge valve is arranged, and a bypass valve is arranged on the bottom surface of the recess to avoid interference between the discharge valve and the bypass valve. Is disclosed.

Japanese Unexamined Patent Publication No. 9-217691

However, in the invention described in Patent Document 1, in order to accelerate the opening of the discharge valve, the head of the bypass valve that closes the bypass port pushes up the discharge valve. That is, the head of the bypass valve and the discharge valve are arranged so as to overlap each other when viewed from the thickness direction of the end plate of the fixed scroll. Such a configuration is necessary for pushing up the discharge valve by the bypass valve, but the fluid discharged from the bypass port may collide with the discharge valve, which rather hinders the operation of the discharge valve. There is a risk.

The present invention has been made in view of such circumstances, and when the discharge valve and the bypass valve are arranged so as to be overlapped with each other when viewed from the plate thickness direction of the plate-shaped member (end plate of the fixed scroll), the bypass is bypassed. It is an object of the present invention to provide a scroll compressor in which the operation of the discharge valve or the bypass valve is not hindered by the fluid discharged from the port or the discharge port.

In order to solve the above problems, the scroll compressor of the present invention employs the following means.
That is, the scroll compressor according to one aspect of the present invention includes a scroll compression mechanism, a plate-shaped member having a discharge port for discharging the fluid compressed by the scroll compression mechanism, and a bypass port for discharging the fluid in the middle of compression. On the discharge side of the discharge port, the discharge valve is a lead valve having a head that closes the discharge port and an arm portion provided between the head and the fixed portion, and the discharge side of the bypass port. A bypass valve as a lead valve having a head that closes the bypass port and an arm portion provided between the head and the fixed portion, and a bypass retainer that regulates the operating range of the bypass valve are provided. The discharge valve and the bypass valve are separated from each other in the plate thickness direction of the plate-shaped member, and their arms are arranged so as to intersect each other when viewed from the plate thickness direction. ..

The discharge valve and the bypass valve are separated from each other in the plate thickness direction of the plate-shaped member, and their arms are arranged so as to intersect each other when viewed from the plate thickness direction. Alternatively, the head of the bypass valve and the arm of the discharge valve are prevented from overlapping when viewed from the plate thickness direction. As a result, it is possible to prevent the fluid discharged from the head of one valve from colliding with the arm portion of the other valve, and it is possible to prevent the operation of the other valve from being hindered.
Examples of the plate-shaped member include an end plate of the fixed scroll, a discharge cover provided on the discharge side of the fixed scroll, and the like.

Further, in the scroll compressor according to one aspect of the present invention, the plate-shaped member is formed with a recess formed from the discharge side surface to an intermediate position in the plate thickness direction, and one of the discharge valve and the bypass valve is formed. , It is characterized in that it is arranged on the bottom surface of the recess.

It was decided to arrange one of the discharge valve and the bypass valve on the bottom surface of the recess formed from the discharge side surface of the plate-shaped member to the intermediate position in the plate thickness direction. As a result, the degree of freedom in the layout of the discharge valve and the bypass valve can be expanded.

Further, in the scroll compressor according to one aspect of the present invention, the lift portion of the discharge valve or the other arm portion of the bypass valve, which is separated from the installation surface when the valve is opened, overlaps the position where the recess is opened. It is characterized in that it is provided so as to.

Of the other arm of the discharge valve or the bypass valve, a lift part that is separated from the installation surface when the valve is opened is provided so as to overlap the position where the concave portion opens. As a result, the area in which the lift portion contacts the installation surface can be reduced by the area corresponding to the area of the opening of the recess, and it becomes difficult for the lift portion to separate while in contact with the installation surface, and the valve opening timing is delayed. Can be avoided. In particular, it is suitable when lubricating oil is present between the installation surface and the valve due to mist lubrication.

Further, in the scroll compressor according to one aspect of the present invention, the discharge valve is arranged on the discharge side surface of the plate-shaped member, and the bypass valve is arranged on the bottom surface of the recess. ..

By arranging the bypass valve on the bottom surface of the recess, the volume of the bypass port can be made smaller than that of the discharge port blocked by the discharge valve installed on the discharge side surface. As a result, it is possible to reduce the top volume on the bypass valve side, which is more likely to cause recompression loss due to the top volume than on the discharge valve side, and suppress a decrease in efficiency.

By preventing the head of the discharge valve and the arm of the bypass valve, or the head of the bypass valve and the arm of the discharge valve from overlapping when viewed from the plate thickness direction of the plate-shaped member, one of the valves It is possible to prevent the fluid discharged from the head from colliding with the arm portion of the other valve, and it is possible to prevent the operation of the other valve from being hindered.

It is a vertical sectional view which showed the scroll compressor which concerns on one Embodiment of this invention. FIG. 1 is a cross-sectional view taken along the line AA of FIG. It is a front view which looked at the fixed scroll from the discharge side. It is a vertical sectional view of a fixed scroll.

Hereinafter, an embodiment according to the present invention will be described with reference to the drawings.
1 and 2 show an example of a scroll compressor to which the present invention can be applied.
The scroll compressor 1 is placed horizontally, and is used, for example, as a compressor for a transport refrigerator.
The scroll compressor 1 includes a housing 2 that constitutes an outer shell. The housing 2 is composed of a bottomed cup-shaped housing 3 whose one end is closed and a front housing 4 which is fitted and mounted on the open end side thereof, and both are integrally tightened and fixed by a bolt or the like. ing.

Inside the front housing 4, a crankshaft 5 is rotatably supported around its axis via a main bearing 6 and a sub bearing 7. One end side (left end side in FIG. 1) of the crankshaft 5 is a small diameter shaft portion 5A, and the small diameter shaft portion 5A penetrates the front housing 4 and projects to the left side of FIG. An electromagnetic clutch, pulley, or the like that receives power from the outside is provided at the externally protruding end of the small diameter shaft portion 5A, and power is input from an external drive source such as an engine via a belt. A lip seal 8 is installed between the main bearing 6 and the sub bearing 7 to seal the inside of the housing 2 and the atmosphere.

A large-diameter shaft portion 5B is provided on the other end side (right end side in FIG. 1) of the crankshaft 5, and the large-diameter shaft portion 5B has a crank pin 5C eccentric by a predetermined dimension from the axis of the crankshaft 5. It is provided integrally. The crankshaft 5 is rotatably supported by the front housing 4 by supporting the large-diameter shaft portion 5B and the small-diameter shaft portion 5A via the main bearing 6 and the sub-bearing 7. A swivel scroll 14 described later is connected to the crank pin 5C via a drive bush 9 and a swivel bearing 10, and the swivel scroll 14 is swiveled by the rotational drive of the crankshaft 5.

The drive bush 9 is provided with a pin hole 9A into which the crank pin 5C is fitted, and the boss portion 14C of the swivel scroll 14 is fitted to the outer periphery of the drive bush 9 fitted to the crank pin 5C via the swivel bearing 10. By doing so, the crankpin 5C and the swivel scroll 14 are connected. The drive bush 9 is provided with a balance weight 11 for removing an unbalanced load generated by turning the swivel scroll 14, and is swiveled together with the swivel scroll 14.

A scroll compression mechanism 12 composed of a pair of fixed scrolls 13 and a swivel scroll 14 is incorporated in the housing 2. The fixed scroll 13 is composed of an end plate (plate-shaped member) 13A and a spiral wrap 13B erected from the end plate 13A, and the swirl scroll 14 stands up from the end plate 14A and the end plate 14A. It is composed of a spiral wrap 14B provided.
On the tooth tip surfaces of the spiral wraps 13B and 14B, a tip seal 16 for sealing the tip seal surface formed between the tooth tip surface and the tooth bottom surface of the mating scroll is fitted and installed in a groove provided on the tooth tip surface. Has been done.

The fixed scroll 13 and the swivel scroll 14 are engaged with each other by separating their centers by the swirling radius and shifting the phases of the spiral wraps 13B and 14B by 180 degrees. It is assembled so that there is a slight clearance in the lap height direction at room temperature. As a result, as shown in FIG. 1, between the scrolls 13 and 14, a pair of compression chambers 15 limited by the end plates 13A and 14A and the spiral wraps 13B and 14B are symmetrical with respect to the scroll center. Along with the formation, the swirl scroll 14 is smoothly swiveled around the fixed scroll 13.

The fixed scroll 13 is fixedly installed on the inner bottom surface of the cup-shaped housing 3 via a plurality of bolts 17. Further, in the swivel scroll 14, as described above, the crank pin 5C provided on one end side of the crankshaft 5 has the drive bush 9 and the swivel bearing 10 with respect to the boss portion 14C provided on the back surface of the end plate 14A. It is connected via. In the swivel scroll 14, the back surface of the end plate 14A is supported by the thrust bearing surface of the front housing 4, and the rotation prevention mechanism 18 such as an old dam link provided between the thrust bearing surface and the back surface of the end plate 14A is used. Therefore, the scroll is driven to revolve around the fixed scroll 13 while being prevented from rotating. The rotation prevention mechanism 18 may be a pin ring type rotation prevention mechanism.

The fixed scroll 13 is opened with a discharge port 13C for discharging the compressed refrigerant gas at the central portion of the end plate 13A, and the discharge port 13C is provided with a discharge valve 19 as a lead valve. A discharge retainer 20 that regulates the operating range of the discharge valve 19 is provided on the side of the discharge valve 19.
On the back side of the end plate 13A of the fixed scroll 13, a discharge chamber 21 partitioned from the internal space of the housing 2 is formed between the end plate 13A and the inner surface of the cup-shaped housing 3.

As shown in FIG. 2, a plurality of pairs of bypass ports 23 are formed on the end plate 13A of the fixed scroll 13 with the discharge port 13C interposed therebetween. Each bypass port 23 is formed so as to communicate between the compression chamber 15 and the discharge chamber 21.

As shown in FIG. 3, in the opening of each bypass port 23 to the discharge chamber 21, when the pressure in each compression chamber 15 exceeds the set pressure, each bypass port 23 is opened to the discharge chamber 21. A bypass valve 24 as a lead valve is provided. By opening the bypass valve 24, overcompression or liquid compression is prevented.

On the other hand, the first bypass valve 24A is mounted on the discharge side surface 13D on the discharge chamber 21 side of the end plate 13A of the fixed scroll 13. A first bypass retainer 25A that regulates the operating range of the first bypass valve 24A is provided on the side of the first bypass valve 24A. One end of the first bypass valve 24A and the first bypass retainer 25A is fixed to the end plate 13A by a fixing bolt 26A.

As shown in FIG. 4, the other second bypass valve 24B is provided at the bottom of the recess 30 formed from the discharge side surface 13D of the end plate 13A of the fixed scroll 13 to an intermediate position in the plate thickness direction. As a result, the second bypass valve 24B and the discharge valve 19 are arranged so as to be separated from each other in the plate thickness direction of the end plate 13A. The recess 30 is provided so that its longitudinal direction is orthogonal to the longitudinal direction of the discharge valve 19 (see FIG. 3).
A second bypass retainer 25B that regulates the operating range of the second bypass valve 24B is provided on the side of the second bypass valve 24B. As shown in FIG. 3, one end of the second bypass valve 24B and the second bypass retainer 25B is fixed to the bottom of the recess 30 by a fixing bolt 26B.

As shown in FIG. 3, one end of the discharge valve 19 and the discharge retainer 20 is fixed to the discharge side surface 13D of the end plate 13A by a fixing bolt 26C.
As shown in FIG. 4, the discharge valve 19 is arranged so as to cover the opening of the recess 30. Specifically, a part of the arm portion 19C provided between the head portion 19A of the discharge valve 19 that closes the outlet of the discharge port 13C and the fixing portion 19B fixed by the fixing bolt 26C is an opening of the recess 30. It is arranged so as to cover. More specifically, of the arm portion 19C of the discharge valve 19, a lift portion separated from the discharge side surface 13D, which is an installation surface when the discharge valve 19 is opened, is arranged so as to cover the opening of the recess 30.

As shown in FIG. 3, the arm portion 24B3 provided between the head portion 24B1 of the second bypass valve 24B that closes the outlet of the bypass port 23 and the fixing portion 24B2 fixed by the fixing bolt 26B, and the discharge valve 19 The arm portion 19C is arranged so as to be orthogonal to the end plate 13A when viewed from the plate thickness direction. That is, the head portion 24B1 of the second bypass valve 24B and the discharge valve 19 are arranged so as not to overlap each other when viewed from the plate thickness direction of the end plate 13A.

The scroll compressor 1 described above operates as follows.
The low-pressure refrigerant gas sucked into the suction chamber 22 in the housing 2 from the suction port (not shown) is sucked into the pair of compression chambers 15 by the swivel drive of the swirl scroll 14. This refrigerant gas is compressed while the compression chamber 15 is moved from the outer peripheral side to the central side in the circumferential direction of the spiral wraps 13B and 14B while reducing the volume, and the pair of compression chambers 15 merge to discharge the port. By communicating with 13C, the discharge valve 19 is opened and discharged into the discharge chamber 21. The discharged high-pressure gas is sent to the outside through a discharge port provided in the housing 2. The refrigerant contains mist-like lubricating oil, which lubricates various parts.

In the compression process, the pressure in the compression chamber 15 may rise abnormally depending on the operating conditions to be in an overcompressed state, or the pressure may rise abnormally by sucking in the liquid refrigerant and compressing the liquid. In such a case, excessive stress due to overcompression or liquid compression may be applied to the spiral laps 13B and 14B of the fixed scroll 13 and the swivel scroll 14, and there is a risk that the spiral laps 13B and 14B will be damaged. In such a case, the refrigerant is relieved from the bypass port 23 opened in each compression chamber 15 to the discharge chamber 21 via the bypass valve 24.

According to this embodiment, the following effects are exhibited.
The discharge valve 19 and the second bypass valve 24B are separated from each other in the plate thickness direction of the end plate 13A of the fixed scroll 13, and the arm portions 19C and 24B3 are arranged so as to intersect each other when viewed from the plate thickness direction. 2 The head portion 24B1 of the bypass valve 24B and the arm portion 19C of the discharge valve 19 are prevented from overlapping when viewed from the plate thickness direction. As a result, it is possible to prevent the refrigerant discharged from the head portion 24B1 of the second bypass valve 24B from colliding with the arm portion 19C of the discharge valve 19, and it is possible to prevent the operation of the discharge valve 19 from being hindered.

The second bypass valve 24B is arranged on the bottom surface of the recess 30 formed from the discharge side surface 13D of the end plate 13A of the fixed scroll 13 to an intermediate position in the plate thickness direction. As a result, the degree of freedom in layout of the discharge valve 19 and the second bypass valve 24B can be expanded.

Of the arm portion 19C of the discharge valve 19, a lift portion separated from the discharge side surface 13D, which is an installation surface when the valve is opened, is provided so as to overlap the opening of the recess 30. As a result, the area in which the lift portion contacts the installation surface can be reduced by only the portion corresponding to the area of the opening of the recess 30, and the lift portion is difficult to separate while in contact with the installation surface, and the valve opening timing is delayed. The state can be avoided. In particular, it is suitable because the lubricating oil exists between the installation surface and the discharge valve 19 due to mist lubrication and has high adhesive strength.

By arranging the second bypass valve 24B on the bottom surface of the recess 30, the volume of the bypass port 23 can be made smaller than that of the discharge port 13C which is closed by the discharge valve 19 installed on the discharge side surface 13D. As a result, the top volume on the bypass valve 24 side, which is more likely to cause recompression loss due to the top volume than on the discharge valve 19 side, can be made smaller to suppress a decrease in efficiency.

In the above-described embodiment, the scroll compressor 1 used in the transport refrigerator placed horizontally is used, but the present invention is not limited to this, and may be placed vertically, for example, or an electric motor. It may be a scroll compressor driven by.

Further, in the present embodiment, the fixed scroll 13 has been described as an example of the plate-shaped member provided with the discharge valve 19 and the bypass valve 24, but for example, in the case where the discharge cover is provided on the discharge side of the fixed scroll (for example). In Japanese Patent Application Laid-Open No. 2013-167215 (see FIG. 2), a discharge valve 19 and a bypass valve 24 may be provided on the discharge cover. In this case, the bypass port is configured to lead to the discharge cover independently of the discharge port.

Further, in the present embodiment, the discharge valve 19 and the second bypass valve 24B are arranged so as to be orthogonal to each other when viewed from the plate thickness direction of the end plate 13A (see FIG. 3). You may make it intersect with.

1 Scroll compressor 12 Scroll compression mechanism 13 Fixed scroll 13A End plate (plate-shaped member)
13C Discharge port 13D Discharge side surface 14 Swing scroll 19 Discharge valve 19A Head 19B Fixed part 19C Arm 20 Discharge retainer 23 Bypass port 24 Bypass valve 24A 1st bypass valve 24B 2nd bypass valve 25A 1st bypass retainer 25B 2nd bypass retainer 26A, 26B, 26C Fixing bolt 30 Recess

Claims (4)

Scroll compression mechanism and
A plate-shaped member having a discharge port for discharging the fluid compressed by the scroll compression mechanism and a bypass port for discharging the fluid in the middle of compression.
A discharge valve as a lead valve having a head that closes the discharge port on the discharge side of the discharge port and an arm portion provided between the head and the fixed portion.
A bypass valve as a lead valve having a head that closes the bypass port on the discharge side of the bypass port and an arm portion provided between the head and the fixed portion.
A bypass retainer that regulates the operating range of the bypass valve,
With
The scroll is characterized in that the discharge valve and the bypass valve are separated from each other in the plate thickness direction of the plate-shaped member, and the arms are arranged so as to intersect each other when viewed from the plate thickness direction. Compressor. The plate-shaped member is formed with a recess formed from the discharge side surface to an intermediate position in the plate thickness direction.
The scroll compressor according to claim 1, wherein one of the discharge valve and the bypass valve is arranged on the bottom surface of the recess. 2. The claim 2 is characterized in that, of the other arm portion of the discharge valve or the bypass valve, a lift portion that is separated from the installation surface when the valve is opened is provided so as to overlap the position where the recess is opened. Scroll compressor described in. The discharge valve is arranged on the discharge side surface of the plate-shaped member.
The scroll compressor according to claim 2 or 3, wherein the bypass valve is arranged on the bottom surface of the recess.

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