JP3068383B2 - Scroll compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor.

[0002]

2. Description of the Related Art Conventionally, there is a scroll type compressor as shown in FIG. That is, a compression mechanism is provided at an upper portion of the housing 1, and a motor (not shown) is provided at a lower portion. The compression mechanism includes a fixed scroll 2 and an orbiting scroll 3
have. The fixed scroll 2 has an end plate 4 and a spiral wrap 5 standing upright on an inner surface thereof, and a discharge port 6 is provided at the center. The orbiting scroll 3 has an end plate 7 and a spiral wrap 8 standing upright on its inner surface. The fixed scroll 2 and the orbiting scroll 3 are mutually eccentric, and are combined with each other at an angle of 180 degrees to form a plurality of closed spaces 9. The orbiting scroll 3 is slidably supported by a casing 10 fixed to the housing 1, and is orbitally revolved by a motor. The fixed scroll 2 is supported by the casing 10 so as to float.

Further, a discharge cover 12 is provided inside the housing 1 to partition a portion provided with a compression mechanism and a high pressure side space 11 above the compression mechanism, and a discharge pipe 13 is provided at a ceiling portion of the housing 1. Have been.

Further, a check valve 14 is provided at the center of the discharge cover 12. That is, a circular through hole 15 is formed in the center of the discharge cover 12, a holding cylinder 16 is provided in the hole 15, a valve element 17 is provided in the holding cylinder 16, and a check valve 14 is provided. It is configured. The check valve 14 allows the flow of gas from the compression mechanism to the high-pressure space, prevents reverse flow of gas from the high-pressure space to the compression mechanism, and reverses the rotation of the orbiting scroll 3 due to the reverse flow of gas. This prevents rotation in the direction in which the enclosed space between the two is widened.

The holding cylinder 16 has a cylindrical shape with both ends opened, and is arranged upright. The lower part of the holding cylinder 16 is inserted into the through hole 15 of the discharge cover 12,
The holding cylinder 1 is placed on the upper surface of the end plate 4 of the fixed scroll 2.
The lower end opening 6 communicates with the discharge port 6 of the fixed scroll 2. The upper part of the holding cylinder 16 protrudes into the high-pressure side space 11 of the housing 1, and the upper end is in contact with the ceiling part of the housing 1 and the opening is closed. One discharge hole 18 is formed in the peripheral wall of the holding cylinder 16 projecting into the high-pressure side space 11. The diameter (opening area) of the discharge hole 18 is set in consideration of the amount of gas projection.

The valve element 14 is provided inside the holding cylinder 16 so as to be movable up and down, moves downward, closes the discharge port 6, floats by the gas protruding from the discharge port 6, and opens the discharge port 6. .

In the compressor constructed as described above, when the compression mechanism is not driven, the valve 1 of the check valve 14
Numeral 7 rests on the upper surface of the fixed scroll 2 by its own weight to close the discharge port 6.

When the compression mechanism is driven, the orbiting scroll 3 is driven by the motor to make a revolving orbiting motion. Then, gas is sucked into the closed space 8 through the inside of the housing 1 from a suction pipe (not shown) provided in the housing 1. Due to the revolving orbiting motion of the orbiting scroll 3, the volume of the closed space 8 is reduced, and the gas is compressed and reaches the center. Here, the gas enters the discharge port 6 of the fixed scroll 2 and presses the valve 17 provided on the upper surface of the end plate 4 of the fixed scroll 2 by the pressure at the inside of the holding cylinder 16 of the check valve 14. increase. Thereby, the discharge port 6 is opened. Then, the valve element 17 is pushed by the gas discharged from the discharge port 6 and moves up inside the holding cylinder 16 to reach the ceiling of the housing 1 beyond the discharge hole 18. As a result, the gas enters the inside of the holding cylinder 16, and then the discharge port 1
The high-pressure space 11 is entered via 8. After that, the gas is discharged
Is discharged to the outside.

When the driving of the compression mechanism stops, the discharge of gas from the discharge port 6 stops, and the compression mechanism becomes negative pressure.
Since the high-pressure space 11 has a high pressure, the valve element 17 moves downward and rests on the upper surface of the end plate 4 of the fixed scroll 2 to close the discharge port 6, so that backflow of gas from the high-pressure space 11 to the compression mechanism is prevented. You.

[0010]

However, the check valve 14 provided in such a conventional scroll type compressor has the following problems. In the check valve 14, the gas discharged from the discharge port 6 of the fixed scroll 2 enters the inside of the holding cylinder 16 and is discharged from the discharge hole 18, so that the valve element 17
Is pushed up to the height position of the discharge hole 18 of the holding cylinder 16 by the gas and moves upward. That is, the lift of the valve element 17 is defined at the height position of the discharge hole 18 from the upper surface of the end plate 4 of the fixed scroll 2.

However, when the height position of the discharge hole 18 of the holding cylinder 16 is low, when the valve element 17 moves up and down in response to the pulsation of the gas discharged from the discharge port 6 when driving the compression mechanism, the valve When the body collides with the upper surface of the end plate 4 of the fixed scroll 2, an abnormal sound is generated, and the valve body 17 closes the discharge port 6, which may hinder the check valve operation.

When the height position of the discharge hole 18 of the holding cylinder 16 is high, the valve 17 is pushed up to a high position by the gas, so that the driving of the compression mechanism is stopped and the valve 17 moves downward. In this case, the speed at which the valve element 17 collides with the upper surface of the end plate 4 is large. For this reason, the collision of the valve element 17 with the end plate 4 generates a loud collision sound, and the valve element 17 may be damaged.

The present invention has been made in view of the above circumstances, and prevents the valve body from colliding with the scroll when the compression mechanism is driven to generate an abnormal sound, and also prevents the valve body from scrolling when the compression mechanism is stopped. It is an object of the present invention to provide a scroll compressor provided with a check valve capable of reducing collision with the scroll.

[0014]

In order to achieve the above object, a scroll type compressor according to the present invention includes a closed space formed by combining a fixed scroll and an orbiting scroll with each other while reducing the area of the two scrolls. A scroll compressor that moves toward the center of the compressor to compress the gas and discharges the gas to the outside through a discharge port formed in the one scroll and a check valve communicating with the discharge port. The check valve is provided with a holding cylinder provided upright in communication with the discharge port, and is provided vertically movably inside the holding cylinder, moves down, closes the discharge port, and projects from the discharge port. A valve body that is moved upward by the gas to open the discharge port, wherein the holding cylinder has a plurality of discharge holes formed at intervals in its length direction, The smallest discharge hole opening area of the discharge hole is characterized in that it is in the position closest to the discharge port. A discharge hole located at a position farthest from the discharge port among the plurality of discharge holes is an opening at an end of the holding cylinder opposite to the discharge port.

[0015]

When the compression mechanism is driven, gas discharged from the discharge port enters the inside of the holding cylinder, and is discharged to the outside through the plurality of discharge holes formed in the holding cylinder in the axial direction. Here, the opening area of the ejection hole located at a position farthest from the ejection port is larger than that of the ejection hole located at the position closest to the ejection port and having the smallest opening area. Therefore, the amount of gas discharged from a discharge hole having a large opening area located at a position distant from the discharge port from the discharge port is smaller than the amount of gas discharged from the discharge hole having the smallest open area at the position closest to the discharge port. The amount is larger.

Accordingly, the valve element rides on the flow of gas discharged from the discharge hole having a large opening area at a position distant from the discharge port, that is, at a position higher than the upper surface of the end plate 4 of the fixed scroll. It moves upward to the height of the discharge hole having a large opening area. Therefore, since the valve element rises to a higher position from the upper surface of the end plate of the fixed scroll, even if the valve element pulsates as the gas pulsates, even if the valve pulsates, the discharge port is formed on the upper surface of the end plate of the scroll where the discharge port is formed. There is no collision, and no abnormal noise is generated due to the valve body colliding with the scroll when the compression mechanism is driven, and the valve body closes the discharge port and does not hinder the valve operation.

When the driving of the compression mechanism is stopped, the flow of the gas flowing from the discharge port into the holding cylinder is stopped, and the valve body is positioned at the position of the discharge hole having a large opening area at a high position away from the discharge port. Then, it moves downward and rests on the upper surface of the end plate of the scroll in which the discharge port is formed. Here, during the processing of the valve element, the resistance of gas (air) protruding from the discharge hole having a small opening area located at a low position near the discharge port inside the holding cylinder and close to the discharge port causes the upper side of the valve element to be closed. The pressure difference with the lower side is very small, so that the lowering speed of the valve body does not increase so much. Therefore, the impact of the valve body colliding with the upper surface of the end plate of the scroll is reduced, so that the collision sound due to the collision of the valve body with the end plate can be reduced, and the valve body can be prevented from being damaged.

By making the discharge port located farthest from the discharge port an opening at the end of the holding cylinder opposite to the discharge port, the structure can be simplified and the production can be simplified.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows the whole scroll compressor. In FIG. 1, the inside of a closed housing 31 is partitioned by a discharge cover 32 into a high-pressure space 33 and a low-pressure space 34. A scroll-type compression mechanism C is provided in the upper part of the low-pressure space 34, and a motor M is provided in the lower part.
However, an oil pump P is further provided at the bottom of the low-pressure space 34 (the bottom of the closed housing 31), and these are driven by a scroll-type compression mechanism C, an electric motor M, and an oil pump P by a rotating shaft 35 provided on the electric motor M. Are linked.

The electric motor M includes a stator 36 fixed to the hermetically sealed housing 31, a rotor 37 combined inside the stator 36, and a rotating shaft 3 fixedly inserted through the rotor 37.
5, and the rotating shaft 35 extends below and above the rotor 37, respectively.

The scroll type compression mechanism C has a fixed scroll 38 and an orbiting scroll 39.
Reference numeral 8 includes an end plate 40 and a spiral wrap 41, and a discharge port 42 is provided in the center in the vertical direction. The orbiting scroll 39 includes an end plate 43 and a spiral wrap 44,
A bush 46 is rotatably fitted into a boss 45 provided on the lower surface of the end plate 43 via a bearing 47, and an eccentric shaft 48 provided at the upper end of the rotary shaft 35 is slidably inserted into the bush 46. Have been.

Fixed scroll 38 and orbiting scroll 39
The end plate 40 and the end plate 43 are eccentric by a predetermined distance, and a plurality of closed spaces 49 are formed in which the wrap 41 and the wrap 44 are combined with each other at an angle of 180 degrees. The orbiting scroll 39 is slidably supported by a casing 50 fixed inside the hermetic housing 31, and between the orbiting scroll 39 and the casing 50,
An anti-rotation mechanism 51 is provided to allow the orbiting scroll 39 to revolve or not, but to prevent rotation.

An outer periphery of an end plate 40 of the fixed scroll 38 is supported by a casing 50 so as to be freely lifted up.
2 and a projection 53 having a central discharge port 42 are formed concentrically.

A back pressure chamber 55 is formed between the flange 52 and the projection 53 so that a cylindrical flange 54 provided on the lower surface of the discharge cover 32 is sealed and slidably fitted. The back pressure chamber 55 is provided with a hole 5 provided in the end plate 40.
6 communicates with a sealed space 49 in the middle of gas compression. Here, the hole 56 is located at a point in contact with the inner peripheral side of the wrap 41, the inner peripheral side of the back pressure chamber 55 is on the high pressure side, and the low pressure chamber 57 is formed on the outer peripheral side. In addition,
A gas suction pipe 58 is provided in a portion of the low pressure space 34 of the sealed housing 31, and a gas discharge pipe 59 is provided in a portion of the high pressure space 35.

Further, the discharge cover 32 is provided with a check valve 71. That is, a circular through hole 60 is formed at the center of the discharge cover 32, a holding cylinder 72 is provided in the hole 60, a valve body 75 is provided inside the holding cylinder 72, and a check valve 71 is provided. It is configured.

The holding cylinder 72 has a cylindrical shape with both ends opened, and is arranged upright. The lower part of the holding cylinder 72 is inserted into the through hole 60 of the discharge cover 32,
The lower end opening of the holding cylinder 72 is placed on the upper surface of the end plate 40 of the fixed scroll 38 and the discharge port 4 of the fixed scroll 38 is
It communicates with 2. The upper part of the holding cylinder 72 is the housing 31
The upper end of the housing 31 is in contact with the ceiling of the housing 31 and its opening is closed.

The peripheral wall of the holding cylinder 72 projecting into the high-pressure side space 33 has a plurality of, for example, 2
The plurality of circular discharge holes 73 and 74 are formed at intervals in the length direction (height direction) of the holding cylinder 72. Of these discharge holes 73 and 74, the opening area (diameter) of the discharge hole 73 at a position where the height from the upper surface of the end plate 40 of the fixed scroll 38 is low, that is, at a position close to the discharge port 42.
Is set smaller than the opening area (diameter) of the discharge hole 74 at a position higher than the discharge hole 73 from the upper surface of the end plate 40 of the fixed scroll 38, that is, at a position distant from the discharge port 42. I have.

The opening area (diameter) of the discharge hole 74 is large enough to obtain a gas flow rate that pushes up the valve body 75 to the position of the discharge hole 74 by the pressure of the gas. When the valve element 75 moves down, the pressure difference between the upper and lower sides of the valve element 75 is as small as possible to obtain a gas flow rate that can be minimized.

The valve body 14 is provided inside the holding cylinder 16 so as to be movable up and down, closes the discharge port by downward movement, is floated by the gas protruding from the discharge port 42 and moves upward to open the discharge port 42. Things.

In the scroll compressor constructed as described above, when the compression mechanism C is not driven, the valve body 75 of the check valve 71 is placed on the upper surface of the end plate 40 of the fixed scroll 38 by its own weight and is located on the upstream side. The discharge port 73 is closed.

When the compression mechanism C is driven, the rotation shaft 35 is rotated by the drive of the motor M, and this rotation is transmitted to the orbiting scroll 39 of the compression mechanism C via the eccentric shaft 48, the bush 46 and the boss 45. You. The orbiting scroll 39 performs a revolving orbiting motion on a circular orbit having a radius of good turning while being prevented from rotating by the rotation preventing mechanism 51.

Then, the gas enters the low-pressure space 34 of the closed housing 31 via the suction pipe 58 and is sucked into the closed section of the compression mechanism C via a path (not shown). And
The closed space 4 is formed by the orbital movement of the orbiting scroll 39.
As the volume of 9 decreases, the gas reaches the center while being compressed.

Here, the gas enters the discharge port 42 of the fixed scroll 38, and at that pressure, the holding cylinder 16 of the check valve 14
Of the fixed scroll 2 on the upper surface of the end plate 4 of the fixed scroll 2 is pushed up. As a result, the discharge port 6 is opened, and the gas is discharged from the discharge port 6 into the holding cylinder 72.

The gas discharged from the discharge port 42 enters the inside of the holding cylinder 72, passes through the holding cylinder 72 through two discharge holes 73 and 74 formed in the axial direction thereof,
To be discharged. Here, the opening area of the ejection hole 74 located farther from the ejection port 42 is larger than the ejection hole 73 located at the position closest to the ejection port 42 and having the smallest opening area. Therefore, the amount of gas discharged from the discharge hole 73 having the smallest opening area at the position closest to the discharge port 42 is determined by the amount of the discharge hole 73.
The amount of gas discharged from the discharge hole 74 having a large opening area located farther from the discharge port 42 is larger.

Then, the valve element 75 is pushed by the gas discharged from the discharge port 42 and moves upward inside the holding cylinder 16 to pass over the discharge hole 73, and is located at a position away from the discharge port, that is, the end plate of the fixed scroll. 4 rides on the flow of the gas discharged from the discharge hole having a large opening area at a position higher than the upper surface of the nozzle 4 and moves upward to the height of the discharge hole having the large opening area.

As described above, the valve body 75 is provided with the fixed scroll 38.
Because the gas rises from the upper surface of the end plate 40 to a high position, even if the valve body 75 pulsates as the gas pulsates, it collides with the upper surface of the end plate 40 of the fixed scroll 38 in which the discharge port 42 is formed. Therefore, the valve body does not collide with the fixed scroll 38 when the compression mechanism C is driven, and an abnormal sound is not generated, and the valve body 75 closes the discharge port 42 and does not interfere with the valve operation. The gas flowing into the high pressure side space 33 is
Is discharged to the outside.

When the driving of the compression mechanism C is stopped, the high pressure side space 33 becomes high pressure and the compression mechanism C becomes negative pressure. From the discharge port 42
Is mounted on the upper surface of the end plate 40 of the fixed scroll 38 on which is formed. As a result, backflow of gas from the high pressure side space 33 to the compression mechanism C is prevented. Here, during the downward movement of the valve element 75, the resistance of gas (air) discharged from the discharge hole 73 having a small opening area in the holding cylinder 72 and located at a low position near the discharge port 42, Valve element 7
The pressure difference between the upper side and the lower side of 5 becomes very small, so that the descending speed of the valve body 74 does not increase so much. Therefore, the impact of the valve body 75 colliding with the upper surface of the end plate 40 of the fixed scroll 38 is reduced, so that the collision sound due to the collision of the valve body 75 with the end plate 40 can be reduced, and the valve body 75 is damaged. Can also be prevented.

The fixed scroll 38 is pressed against the orbiting scroll 39 by the gas pressure in the back pressure chamber 55 to prevent the gas from leaking from the inside of the closed space 49.
When the liquid is sucked into the closed space 49, the fixed scroll 38 floats and escapes the liquid, thereby preventing the compression mechanism from being damaged.

The oil pump P incorporated in the lower portion of the housing 31 is driven by the rotating shaft 35 to suck the lubricating oil stored in the bottom of the housing 31 and formed on the rotating shaft 35. It is supplied to the sliding part of the compression mechanism C through the hole 35a.

Another embodiment will be described with reference to FIG. The scroll compressor of this embodiment is different from the above-described scroll compressor in the configuration of the check valve, and the other parts are the same as the scroll compressor of the above-described embodiment, and therefore description thereof is omitted. I do. In this embodiment, the configuration of the valve chamber shown in FIG. 3 will be described. 3, the same parts as those in FIG. 2 are denoted by the same reference numerals.

In this embodiment, two discharge holes 77 and 78 are formed in the holding cylinder 76. One discharge hole 77 is
The other discharge hole 78 formed on the peripheral wall of the holding cylinder 76 is formed as an opening at the upper end of the holding cylinder 76. The discharge hole 77 corresponds to a discharge hole having a small opening area near the discharge port 42, and the discharge hole 78 corresponds to a discharge hole having a large opening area apart from the discharge port 42. The valve body 79 inserted into the holding cylinder 76 has a hole 80 formed therein.

In such a configuration, when the compression mechanism is driven and gas is discharged from the discharge port 42 into the holding cylinder 76, the valve body 79 is pushed by the gas and the holding cylinder 76 at the position of the discharge hole 78 is pressed. Move up to the top opening of the. Gas escapes from the lower side of the valve body 79 through the hole 80 to the upper side, and the holding body 7
6 is discharged to the high pressure side space 33 from the upper end opening. Also,
When the driving of the compression mechanism is stopped, the lowering speed of the valve body 79 is suppressed by the presence of the discharge hole 77.

In this embodiment, the discharge port 78 located farthest from the discharge port 42 is formed as an opening at the end of the holding cylinder 72 on the opposite side to the discharge port 42.
It is not necessary to form the discharge hole 78 in the peripheral wall, and the configuration can be simplified and the manufacturing can be simplified.

The present invention is not limited to the above-described embodiment, but can be implemented with various modifications. For example, the number of discharge holes formed in the holding cylinder is not limited to two, but may be three or more.

[0045]

As described above, according to the present invention, it is possible to prevent the valve body from colliding with the scroll when the compression mechanism is driven and generating abnormal noise, and to prevent the valve body from scrolling when the compression mechanism is stopped. And a scroll compressor provided with a check valve capable of alleviating collision with the scroll compressor. Further, by making the discharge hole located farthest from the discharge port an opening at the end of the holding cylinder opposite to the discharge port, the configuration can be simplified and the production can be simplified.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a scroll compressor according to an embodiment of the first invention.

FIG. 2 is an enlarged sectional view showing a check valve provided in the scroll compressor according to the embodiment.

FIG. 3 is an enlarged sectional view showing a check valve provided in a scroll compressor according to another embodiment.

FIG. 4 is a cross-sectional view showing an example of a conventional scroll compressor.

[Explanation of symbols]

31 ... housing, 38 ... fixed scroll,
39: orbiting scroll; 71: check valve; 72: holding cylinder; 73, 74: discharge hole 75: valve body.

Claims (2)

(57) [Claims] 1. A closed space formed by combining a fixed scroll and an orbiting scroll with each other is moved toward the center of both scrolls while reducing the area thereof to compress gas, and the gas is compressed by the one of the two scrolls. In a scroll type compressor which discharges to the outside via a discharge port formed in a scroll and a check valve communicating with the discharge port, the check valve is provided in an upright manner in communication with the discharge port. And a valve body which is provided movably up and down inside the holding cylinder, moves downward to close the discharge port, and is moved upward by the gas protruding from the discharge port to open the discharge port, A plurality of discharge holes are formed at intervals in the length direction of the holding cylinder, and among the discharge holes, the discharge hole having the smallest opening area is located closest to the discharge port. Scroll compressor, characterized in that in the. 2. The discharge hole at a position farthest from the discharge port among the plurality of discharge holes is an opening at an end of the holding cylinder opposite to the discharge port. Scroll type compressor.