JP6750548B2 - Scroll compressor - Google Patents

Description

The present invention relates to a scroll compressor.

Patent Document 1 discloses a conventional scroll compressor. This scroll compressor includes a housing, a rotary shaft, a fixed scroll, a movable scroll, a rotation preventing mechanism, a back pressure chamber, a back pressure supply passage, and a throttle passage.

The rotary shaft is rotatably supported by the housing. The fixed scroll is fixed to the housing. The movable scroll is housed in a housing and driven by a rotating shaft to form a compression chamber together with the fixed scroll. The rotation preventing mechanism is provided between the housing and the movable scroll and prevents rotation of the movable scroll due to rotation of the rotating shaft. The back pressure chamber is formed by the housing and the movable scroll on the back side of the movable scroll, and urges the movable scroll toward the compression chamber. The back pressure supply passage supplies the high pressure refrigerant or lubricating oil in the compression chamber to the back pressure chamber. The throttle passage connects the suction region for supplying the refrigerant to the compression chamber and the back pressure chamber. Specifically, the throttle passage is provided so as to penetrate through the rotary shaft, and has a passage cross-sectional area reduced by a bearing device provided between the housing and the rotary shaft.

In this scroll type compressor, the refrigerant or lubricating oil whose pressure is high in the compression chamber is supplied to the back pressure chamber, and the amount of the refrigerant or lubricating oil in the back pressure chamber is limited by the throttle passage and discharged to the suction region. .. Therefore, an appropriate amount of refrigerant or lubricating oil having an appropriate back pressure is present in the back pressure chamber, and an appropriate pressing force for pressing the movable scroll against the fixed scroll is applied. Airtightness is preferably maintained.

Patent No. 5315933

However, in the above-mentioned conventional scroll compressor, the throttle passage is provided through the relatively long rotary shaft, which causes a rise in the manufacturing cost. Further, in the above-described conventional scroll compressor, the throttle passage is always open, and there is a concern that the efficiency may decrease due to insufficient back pressure.

The present invention has been made in view of the above-mentioned conventional circumstances, and an object of the present invention is to provide a scroll-type compressor that can reduce manufacturing cost and improve efficiency.

A scroll compressor of the present invention includes a housing, a rotary shaft rotatably supported by the housing, a fixed scroll fixed to the housing, a housing housed in the housing, and driven by the rotary shaft. A movable scroll that forms a compression chamber together with a fixed scroll, a rotation prevention mechanism that is provided between the housing and the movable scroll, and that prevents rotation of the movable scroll due to rotation of the rotating shaft, the housing, and the movable scroll. And a back pressure chamber for urging the movable scroll toward the compression chamber, a back pressure supply passage for supplying the high pressure refrigerant or lubricating oil in the compression chamber to the back pressure chamber, and the compression In a scroll compressor including a suction passage for connecting a suction region for supplying a refrigerant to the chamber and the back pressure chamber,
The rotation preventing mechanism includes three or more ring pockets that are recessed in the back side surface of the movable scroll, a cylindrical ring that is loosely fitted in each of the ring pockets, and is fixed to the housing. A cylindrical pin protruding into the ring,
The suction area is located on the outer peripheral side of the movable scroll,
The throttle passage communicates at least one of the ring pocket and the suction region at a specific position of the ring pocket ,
The specific position is such that an imaginary circle whose radius is a pitch circle radius of the ring pocket and an inner peripheral surface of the ring pocket is centered on a midpoint between the axis of the rotation shaft and the axis of the eccentric shaft. wherein the position der Rukoto crossing.

In the scroll compressor of the present invention, since the throttle passage communicates with at least one ring pocket of the rotation preventing mechanism and the suction region located on the outer peripheral side of the movable scroll, the throttle passage is provided through the rotary shaft. It is possible to make the throttle passage shorter than that of the scroll type compressor. Further, since the throttle passage is provided through the gap between the ring pocket and the ring, the throttle effect is high and the efficiency is improved.

Therefore, in the scroll compressor of the present invention, it is possible to reduce the manufacturing cost and improve the efficiency.

The throttle passage communicates with a specific position of the ring pocket . This specific position is a position where an imaginary circle whose radius is the pitch circle radius of the ring pocket and the inner peripheral surface of the ring pocket intersect with each other around the center of the axis of the rotating shaft and the center of the eccentric shaft. is there. Therefore, the throttle passage is once when one rotation of the rotary shaft becomes to be opened and closed by the ring, the refrigerant and lubricating oil in the back pressure chamber is to be discharged intermittently inlet area. Therefore, it is possible to reduce the amounts of the refrigerant and the lubricating oil discharged to the suction region compared with the case where the throttle passage is always open, and the efficiency of the scroll compressor is improved.

Although it is possible to provide a plurality of throttle passages, one throttle passage is preferable. If only one throttle passage is formed, the effect of lowering the manufacturing cost becomes greater.

With the scroll compressor of the present invention, it is possible to reduce the manufacturing cost and improve the efficiency.

FIG. 1 is a cross-sectional view of the electric scroll compressor of the embodiment. FIG. 2 is an enlarged cross-sectional view of the essential parts of the electric scroll compressor of the embodiment. FIG. 3 is a cross-sectional view of a fixed scroll and a movable scroll at a certain rotation angle according to the electric scroll compressor of the embodiment. FIG. 4 is a cross-sectional view of the rotation preventing mechanism according to the electric scroll compressor of the embodiment at a certain rotation angle. FIG. 5 is a partially enlarged sectional view of FIG. FIG. 6 is a partially enlarged cross-sectional view similar to FIG. 5 in a state in which 90° rotation has advanced from the state of FIG. FIG. 7 is a partially enlarged cross-sectional view similar to FIGS. 5 and 6 in a state in which 90° rotation has advanced from the state of FIG. 6.

An embodiment in which the present invention is embodied in an electric scroll compressor will be described below with reference to the drawings. In this electric scroll compressor, as shown in FIG. 1, a bottomed cylindrical front housing 1 and a lid-shaped rear housing 3 are joined together. A fixed block 5 on the front housing 1 side and a fixed scroll 7 on the rear housing 3 side are sandwiched between the front housing 1 and the rear housing 3. The front housing 1, the rear housing 3, and the fixed block 5 correspond to the housing 8.

The fixed scroll 7 has a fixed base plate 7a located on the rear housing 3 side, and a fixed spiral wall 7b extending forward from the fixed base plate 7a and forming a spiral shape. The fixed substrate 7a forms the discharge chamber 11 together with the rear housing 3. An O-ring 13 located around the discharge chamber 11 is provided between the fixed substrate 7 a and the rear housing 3.

A movable scroll 9 is provided between the fixed block 5 and the fixed scroll 7. The movable scroll 9 has a movable substrate 9a located on the fixed block 5 side, and a movable scroll wall 9b extending backward from the movable substrate 9a and forming a spiral shape. The fixed spiral wall 7b and the movable spiral wall 9b mesh with each other, and the fixed substrate 7a, the fixed spiral wall 7b, the movable substrate 9a, and the movable spiral wall 9b form a compression chamber 10. The movable substrate 9a forms a back pressure chamber 15 together with the fixed block 5. A seal ring 17 located around the back pressure chamber 15 is provided between the movable substrate 9a and the fixed block 5.

A boss portion 5a protruding into the front housing 1 is formed in the fixed block 5, and a main bearing 19 and a seal member 21 are provided in the boss portion 5a. A boss portion 1a protruding toward the fixed block 5 is formed in the front housing 1, and a motor bearing 23 is provided in the boss portion 5a. A rotary shaft 25 is provided between the main bearing 19 and the motor bearing 23 so as to be rotatable around a rotary shaft center O. The seal member 21 is in contact with the rotating shaft 25 between the main bearing 19 and the motor bearing 23. The back pressure chamber 15 is sealed by a seal ring 17 and a seal member 21. Further, the front housing 1 and the fixed block 5 form a motor chamber 27. The motor chamber 27 is a suction chamber connected to an external evaporator by a suction port (not shown) formed in the front housing 1.

In the motor chamber 27, the stator 29 is fixed to the front housing 1 and the rotor 31 is fixed to the rotating shaft 25. An electric current flows through the stator 29 by a harness (not shown). The stator 29 and the rotor 31 correspond to the motor mechanism M.

An eccentric pin 25a, which is eccentric with respect to the rotation axis O and projects in the direction of the eccentric axis Q, is formed at the tip of the rotation shaft 25 located in the back pressure chamber 15. As shown in FIG. 2, a bush 33 is fitted to the eccentric pin 25a. In the bush 33, a cylindrical bush body 33a and a weight 33b are integrated. The movable substrate 9a of the movable scroll 9 is provided with a movable boss 9c protruding toward the rotary shaft 25, and a bush bearing 35 is provided in the boss portion 9a. The bush bearing 35 pivotally supports the bush body 33a.

As shown in FIG. 4, six ring pockets 37 are recessed on the back surface of the movable substrate 9a of the movable scroll 9. A cylindrical ring 39 is loosely fitted in each ring pocket 37. Further, a cylindrical pin 41 protruding into each ring 39 is fixed to the rear surface of the fixed block 5. The inner peripheral surface of each ring pocket 37, the outer peripheral surface and inner peripheral surface of the ring 39, and the outer peripheral surface of the pin 41 extend parallel to the rotation axis O and the eccentric axis Q. Therefore, each ring 39 rolls on the inner peripheral surface of the ring pocket 37, and each pin 41 rolls on the inner peripheral surface of the ring 39. All the ring pockets 37, rings 39, and pins 41 form a rotation preventing mechanism 42.

As shown in FIGS. 1 and 2, a back pressure hole 43 is formed on the center side of the movable base plate 9a and the movable scroll wall 9b of the movable scroll 9. The back pressure hole 43 allows the compression chamber 10 and the back pressure chamber 15 to communicate with each other by slightly tilting the movable scroll wall 9b or slightly separating from the fixed base plate 7a of the fixed scroll 7. The back pressure hole 43 corresponds to the back pressure supply passage.

The fixed block 5 has a suction passage 45 penetrating the motor chamber 27 and the outer peripheral side of the movable scroll 9. Therefore, the suction port 47 is formed on the outer peripheral side of the movable scroll 9. The motor 27 also serving as the suction chamber, the suction passage 45, and the suction port 47 correspond to the suction region 49.

As shown in FIG. 1, the fixed base plate 7a of the fixed scroll 7 has a discharge port 51 formed therethrough, and a discharge valve 53 that closes the discharge port 51 in the discharge chamber 11 is provided on the rear surface of the fixed base plate 7a. It is provided with a retainer 55. The rear housing 3 is provided with an oil separation chamber 59 that communicates with the discharge chamber 11 through the discharge passage 57. In the oil separation chamber 59, a separation cylinder 61 for separating the lubricating oil from the high pressure refrigerant discharged from the discharge passage 57 is provided.

A filter 63 is provided at the lower end of the oil separation chamber 59, and the inside of the filter 63 communicates with the outer circumference of the fixed block 5 and the fixed scroll 7 by an oil supply passage 65 formed in the rear housing 3, the fixed scroll 7, and the fixed block 5. ing. In the oil supply passage 65, a throttle having a small passage cross-sectional area is formed on the way. The outer peripheral sides of the fixed block 5 and the fixed scroll 7 communicate with the motor chamber 27. A discharge port 59a connected to an external condenser is formed at the upper end of the oil separation chamber 59.

In this electric scroll compressor, when the stator 29 is energized, the rotor 31 rotates around the rotation axis O and the bush 33 revolves around the rotation axis O. Therefore, the compression chamber 10 approaches the rotation axis O from the outer peripheral side to reduce the volume. Therefore, the compression chamber 10 sucks and compresses the low-pressure refrigerant in the motor chamber 27, the suction passage 45, and the suction port 47. Then, the high-pressure refrigerant in the compression chamber 10 pushes the discharge valve 53 open and is discharged into the discharge chamber 11. The high-pressure refrigerant in the discharge chamber 11 is discharged from the discharge port 59a after separating the lubricating oil by the separation cylinder 61 in the oil separation chamber 59. A proper amount of the lubricating oil stored in the oil separation chamber 59 is returned to the motor chamber 27 through the filter 63 and the oil supply passage 65. The lubricating oil in the motor chamber 27 lubricates the motor bearing 23.

Further, an appropriate amount of high-pressure refrigerant and lubricating oil in the compression chamber 10 is supplied to the back pressure chamber 15 via the back pressure hole 43. Therefore, the pressure in the back pressure chamber 15 is increased, and the movable scroll 9 is pressed toward the fixed scroll 7. Further, the lubricating oil in the back pressure chamber 15 lubricates the main bearing 19, the bush bearing 35, the seal ring 17, the seal member 21, and the rotation preventing mechanism 42.

In the meantime, in this electric scroll compressor, as shown in FIG. 3, the center of the fixed spiral wall 7b is located at the rotation axis O and the center of the movable spiral wall 9b is located at the eccentric axis Q. Then, the compression reaction force F acting on the compression chamber 10 due to the rotation of the rotating shaft 25 intersects the movable spiral wrap 9b with the line segment OQ from the action point P which is the midpoint between the rotating shaft center O and the eccentric shaft center Q. Acts in the direction. Therefore, as shown in FIGS. 5 to 7, in the rotation preventing mechanism 42, the ring 39 and the pin 41 press the ring pocket 37 by the compression reaction force F to prevent the movable scroll 9 from rotating. With the revolution of the orbiting scroll 9 , the ring pocket 37 on which the compression reaction force F acts changes in sequence.

For example, as shown in FIG. 4, in the ring pockets 37 facing each other, the ring 39 presses the ring pocket 37 with the compression reaction force F. For this reason, when the virtual circle C having the radius of the pitch circle of the ring pocket 37 as the radius is centered on the point of action P, the position S where the virtual circle C and the inner peripheral surface of the ring pocket 37 intersect is determined. .. In this electric scroll compressor, the inner peripheral surface of one ring pocket 37 and the suction port 47 are communicated with each other by the throttle passage 67 extending from the position S in the tangential direction of the ring pocket 37. 6 and 7, the compression reaction force F acts on the ring pocket 37 (not shown). The cross sections shown in FIGS. 3 and 4 are viewed from the same direction.

In this electric scroll compressor, since the throttle passage 67 communicates with one ring pocket 37 of the rotation preventing mechanism 42 and the suction region 49 located on the outer peripheral side of the movable scroll 9, the throttle shaft penetrates the throttle passage. It is possible to make the throttle passage 67 shorter than the conventional scroll type compressor provided. In addition, only one throttle passage 67 is formed.

In particular, the throttle passage 67 communicates with the ring pocket 37 at a specific position. Therefore, the throttle passage 67 is opened and closed once by the ring 39 when the rotary shaft 25 makes one rotation, and the refrigerant and the lubricating oil in the back pressure chamber 15 are intermittently discharged to the suction region 49. Become. Therefore, it is possible to reduce the amount of the refrigerant and the lubricating oil discharged to the suction region 49 as compared with the case where the throttle passage 67 is always open, and the performance of the electric scroll compressor is improved.

Therefore, with this electric scroll compressor, it is possible to reduce the manufacturing cost and improve the efficiency.

Although the present invention has been described with reference to the embodiments, the present invention is not limited to the above embodiments, and it goes without saying that the present invention can be appropriately modified and applied without departing from the spirit thereof.

For example, in the above embodiment, the back pressure hole 43 formed in the movable base plate 9a and the movable spiral wall 9b of the movable scroll 9 is used as the back pressure supply passage, but the oil supply passage 65 connected to the back pressure chamber 15 is used as the back pressure supply passage. It is also possible to

Further, although the present invention is embodied in the electric scroll type compressor in the above embodiments, the present invention can be embodied in a belt type scroll type compressor.

INDUSTRIAL APPLICABILITY The present invention can be used for a vehicle air conditioner.

8... Housing (1... Front housing, 3... Rear housing)
25... Rotating shaft 7... Fixed scroll 10... Compression chamber 9... Movable scroll 42... Rotation prevention mechanism 15... Back pressure chamber 43... Back pressure supply path (back pressure hole)
49... Suction area (27... Motor chamber (suction chamber), 45... Suction passage, 47... Suction port)
67... throttle passage 37... ring pocket 39... ring 41... pin P... point of action C... virtual circle S... position

Claims (2)

A housing, a rotating shaft rotatably supported by the housing, a fixed scroll fixed to the housing, and a movable housing housed in the housing and driven by the rotating shaft to form a compression chamber together with the fixed scroll. A scroll, a rotation prevention mechanism that is provided between the housing and the movable scroll and that prevents rotation of the movable scroll due to rotation of the rotating shaft, and is formed by the housing and the movable scroll. A back pressure chamber for urging to the compression chamber side, a back pressure supply path for supplying the high pressure refrigerant or lubricating oil in the compression chamber to the back pressure chamber, and a suction for supplying the refrigerant to the compression chamber. In a scroll compressor including a throttle passage that connects a region and the back pressure chamber,
The rotation preventing mechanism includes three or more ring pockets that are recessed in the back side surface of the movable scroll, a cylindrical ring that is loosely fitted in each of the ring pockets, and is fixed to the housing. A cylindrical pin protruding into the ring,
The suction area is located on the outer peripheral side of the movable scroll,
The throttle passage communicates at least one of the ring pocket and the suction region at a specific position of the ring pocket ,
The specific position is such that an imaginary circle whose radius is a pitch circle radius of the ring pocket and an inner peripheral surface of the ring pocket is centered on a midpoint between the axis of the rotation shaft and the axis of the eccentric shaft. scroll compressor, wherein position der Rukoto crossing. The throttle passage scroll compressor according to claim 1 wherein the one.

Images