JP2940365B2 - 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 mainly used for a refrigeration system.

[0002]

2. Description of the Related Art Conventionally, a scroll compressor is provided with a seal ring on the back side of a movable scroll in a compression element as described in, for example, Japanese Patent Application Laid-Open No. 4-365982, and a low pressure A back pressure chamber for applying back pressure is formed by partitioning from the side, and an oil injection passage for injecting high pressure lubricating oil introduced into the back pressure chamber into the compression chamber of the compression element is formed in the seal ring. Is known.

That is, as shown in FIG. 3, this scroll compressor includes a compression element D composed of fixed and movable scrolls B and C, A motor F having a drive shaft E for revolving drive and a bearing housing G for supporting a compression element side end of the drive shaft E are provided. The fixed scroll B is provided with a suction port B1 and a discharge port B2. A suction pipe H protruding from the outside of the top of the casing A is connected to the suction port B1, and the discharge port B2 is opened inside the top of the casing A on the side opposite to the housing of the compression element D. A discharge chamber A1 is provided, and the discharge chamber A1 is connected to a motor side space A2 in which the motor F is disposed.
The external discharge pipe J is opened in the motor side space A2 to form a high pressure dome shape, and the suction pipe H
The gas fluid sucked into the suction port B1 is introduced into the compression chamber D1 formed between the scrolls B and C of the compression element D and compressed, and the gas fluid compressed in the compression chamber D1 is discharged. The discharge gas fluid is discharged from the outlet B2 into the discharge chamber A1, and the discharged gas fluid flows from the communication path I to the space A for motor arrangement.
2, and the liquid is discharged from the space A2 to the outside via the discharge pipe J.

The drive shaft E has an upper side bearing supported by the bearing housing G via a first bearing K1 and an eccentric pin portion E1 provided at the upper end of the drive shaft E. Cylindrical boss C protruding from the back side of
1, a boss portion C1 and an eccentric pin portion E1, a second bearing K2 is interposed between the boss portion C1 and the eccentric pin portion E1, and an oil supply pump (not shown) provided at the lower end of the drive shaft E ), The oil pumped into the oil supply passage E2 in the drive shaft E is supplied to the first and second bearings K1 and K2 for lubrication.

Further, inside the bearing housing G, a seal ring accommodating portion G1 is formed around an outer periphery of a connecting portion between the orbiting scroll B2 and the drive shaft E, and the accommodating portion G1 is formed.
The first and second bearings K1 and K2 are collectively stored with oil, and a seal ring L is disposed in the housing portion G1. A spring L1 for constantly pressing the upper surface of the seal ring L against the rear surface of the orbiting scroll C is interposed between the bottom surface of the housing portion G1 of the housing G and the outer peripheral surface of the seal ring L. An O-ring L2 is interposed between the gasket and the inner peripheral surface of the seal ring accommodating portion G1. The back pressure chamber M facing the central portion of the back surface of the movable scroll C to which the largest axial load is sometimes applied is connected to the low pressure side space of the housing G which is communicated with the suction port B1 at the outer peripheral portion of the movable scroll C. G2 is formed so as to be partitioned, high-pressure oil after lubricating the bearings K1 and K2 is introduced into the back-pressure chamber M, and a back-pressure is applied to the movable scroll C by the high-pressure oil. The load acting on the movable scroll C in the axial direction outward from the compression chamber is balanced to prevent the movable scroll C from being deformed in the axial direction by the compressed gas.

An annular oil groove L3 is provided on the upper surface of the seal ring L, and a small-diameter oil injection passage L4 is formed in the seal ring L so as to penetrate the seal ring L in the vertical direction. While the oil groove L3 communicates with the back pressure chamber M, an oil injection hole C2 communicating with the gas fluid suction side is formed on the back surface of the movable scroll C, and the oil injection hole C2 is When the oil groove L3 and the oil injection hole C2 face each other intermittently during the revolving drive, the oil in the back pressure chamber M is restricted by the oil injection passage L4. To the low-pressure side compression chamber D1 of the compression element D while giving
An oil film is formed between the contact portions of the scrolls in the scrolls B and C to maintain the airtightness of the compression chambers D1 and prevent burning.

[0007]

According to the above construction, the bearing housing G is provided with the seal ring housing G1, and the seal ring L and O are provided in the housing G1.
By disposing the ring L2, the rear side of the orbiting scroll C is partitioned into a back pressure chamber M located at the center and an outer low pressure side space G2, and high-pressure oil flows out into the low pressure side space G2. Without applying pressure to the movable scroll C in the back pressure chamber M, and when the orbiting of the movable scroll C revolves, the oil in the back pressure chamber M is supplied to the oil injection passage L4.
Can be injected between the scrolls of the scrolls B and C through the oil groove L3 and the oil injection hole C2. An annular oil groove L3 is provided on the upper surface side of the seal ring L. In the ring L, the accommodation portion G1
It is necessary to form a small-diameter oil injection passage L4, which supplies the oil inside the oil groove L3 while giving a throttle resistance, so as to penetrate the oil in the vertical direction.
Since it is necessary to form the oil injection hole C2 intermittently opposed to the oil groove L3 at the time of the revolving drive, much processing such as troublesome drilling work is required.
In order to partition the back pressure chamber M from the low pressure side space G2 so that oil does not leak, an O-ring is provided between an outer peripheral surface of the seal ring L and an inner peripheral surface of the seal ring housing portion G1. Since it is necessary to interpose L2, the number of parts is increased and the cost is increased.

An object of the present invention is to apply a back pressure by high-pressure oil to the rear central portion of a movable scroll without requiring a complicated processing operation, reducing the number of parts, and reducing the cost. It is an object of the present invention to provide a scroll compressor capable of injecting a necessary optimum amount of oil into a compression chamber of the compression element while preventing bending deformation of the scroll, thereby maintaining airtightness in the compression chamber and preventing burning. is there.

[0009]

In order to achieve the above object, the invention according to claim 1 comprises a drive shaft 3 having an oil supply pump P and a compression element 2 having a movable scroll 22 driven by the drive shaft 3. And a bearing housing 5 for supporting the drive shaft 3. The bearing housing 5 is provided with a seal ring receiving portion 51, and the seal ring receiving portion 51 is brought into pressure contact with the back surface of the orbiting scroll 22 to press the compression ring. In a scroll compressor provided with a seal ring 11 defining a back pressure chamber 12 for applying a back pressure to the back surface of the orbiting scroll 22, a low pressure side communicating with the suction port of the element 2 is provided. The oil supplied from the oil supply pump P to the back pressure chamber 12 is supplied to the low pressure side of the compression element 2 between the outer peripheral surface and the inner peripheral surface of the seal ring housing portion 51 facing the outer peripheral surface. The injection gap 13 to flow than is provided.

Further, according to the present invention, the injection gap 13 is provided with a clearance for obtaining a required injection amount in the compression chamber of the compression element 2, and the bearing housing 5 is provided with the housing 5.
And an oil return passage 15 for returning the oil supplied from the oil collecting chamber 14 to the oil reservoir O of the closed casing 1 in which the compression element 2 is provided. The sectional area is such that the oil collecting chamber 14 can be filled with oil with respect to the pump capacity of the pump P.

[0011]

According to the first aspect of the present invention, the seal ring 1 is provided.
Since the injection gap 13 is provided between the outer peripheral surface on the low pressure side of FIG. 1 and the inner peripheral surface of the seal ring accommodating portion 51, the back side of the movable scroll 22 is sucked by the seal ring 11 into the compression element 2. A low-pressure side communicating with the mouth and a back-pressure chamber 12 for applying a back pressure to the back of the orbiting scroll 22 are partitioned, and high-pressure oil introduced into the back-pressure chamber 12 moves the back to the back of the orbiting scroll 22. As a result, a part of the oil in the back pressure chamber 12 is injected from the injection gap 13 into the compression chamber of the compression element 2 while the pressure is applied, and thus the bending deformation of the movable scroll 22 can be prevented. is there. Moreover, the injection of oil into the compression chamber does not have to bother to form a passage as in the prior art, but a simple configuration in which a predetermined clearance is provided between the seal ring housing portion 51 and the seal ring 11. It can be formed without the need for a lot of processing such as troublesome drilling work for forming the injection passage as in the past, and the clearance is controlled so that the injection oil amount can be adjusted to the appropriate oil amount. It can be adjusted, and since there is no need to seal using an O-ring between the seal ring 11 and its accommodating portion 51 as in the conventional case, the number of parts can be reduced without the need for the O-ring, Cost reduction is possible as a whole.

According to the second aspect of the present invention, the injection gap 13 is a clearance for obtaining a required injection amount in the compression chamber of the compression element 2, and the oil return passage 1 provided in the bearing housing 5.
5, that is, lubricating the lubrication point of the bearing housing 5,
The cross-sectional area of the oil return passage 15 for returning the oil collected in the oil collecting chamber 14 from the oil collecting chamber 14 to the oil reservoir O of the closed casing 1 is set in the oil collecting chamber 14 with respect to the pump capacity of the oil supply pump P. Since the cross-sectional area is set to be fillable, the oil after being pumped by the refueling pump P and supplied to the refueling point can always be filled in the oil collecting chamber 14, that is, the seal ring accommodating portion 51. Inside the back pressure chamber 1
2 to the injection gap 13
Thus, a predetermined amount of oil can always be injected into the compression chamber of the compression element 2 from the entire area of the compression element 2, so that airtightness in the compression chamber and prevention of burning can be more reliably performed.

[0013]

FIG. 2 shows the whole structure of a high-pressure dome type horizontal scroll compressor. A fixed scroll 21 is provided on one side in the horizontal direction inside a horizontal closed casing 1 having an oil reservoir O on an inner bottom. Compression element 2 comprising movable scroll 22
And a motor 4 having a drive shaft 3 for driving the compression element 2 is provided on the other side of the casing 1, and a first bearing housing 5 is provided on the compression element side of the casing 1. The first and second scroll bearings 21 and 22 are supported by the first bearing housing 5, while a second bearing housing 6 is provided on the anti-compression element side of the motor 4. Bearing housing 6
The first and second bearings 71 and 72 provided on the drive shaft 3 support the longitudinal sides of the drive shaft 3.

More specifically, a cylindrical transmission portion 31 eccentric to the axis of the drive shaft 3 is provided at the end of the drive shaft 3 facing the movable scroll 22, and On the back side of 22, a pin portion 23 fitted into the transmission portion 31 is protrudingly provided, and the pin portion 23 is rotatably supported in the transmission portion 31 via a third bearing 73. An Oldham ring 8 is interposed between the movable scroll 22 and the first bearing housing 5, and the movable scroll 22 revolves with respect to the fixed scroll 21 by the rotation of the drive shaft 3 accompanying the driving of the motor 4. Like that.

An oil supply passage 32 is formed in the shaft center of the drive shaft 3 so as to penetrate the drive shaft 3 in its length direction. A trochoid-type positive displacement oil supply pump P having a variable amount is attached, and the pump P forcibly pumps oil in an oil reservoir O provided in the casing 1 into the oil supply passage 32. The first to third bearings 71 to 71
73 is actively refueled and lubricated. More specifically, an oil groove 33 extending in an oblique direction is formed on the outer peripheral surface of the cylindrical transmission portion 31 facing the first bearing 71, and one end in the length direction of the oil groove 33 is connected to the drive shaft 3. Is communicated with the oil supply passage 32 through an oil hole 34 penetrating in the radial direction, so that the oil pumped up in the oil supply passage 32 is supplied to the first bearing 71 through the oil hole 34 and the oil groove 33. An oil hole for supplying oil between an inner peripheral surface and an outer peripheral surface of the transmission portion 31 and penetrating in a radial direction to a portion of the drive shaft 3 facing the second bearing 72 and communicating with the oil supply passage 32. (Not shown) so as to supply pumping oil to the oil supply passage 32 to the second bearing 72 through the oil hole, and further to an inner bottom side of the cylindrical transmission portion 31. And the end face of the pin portion 23, the oil supply passage 32 is opened, and 3 oil supply gap 35 communicating with the bearing 73
Is provided so that pumping oil from the gap 35 to the oil supply passage 32 is supplied to the third bearing 73.

Further, a suction pipe 9 is connected to a suction port provided in the fixed scroll 21, and the gas fluid sucked from the suction pipe 9 is supplied to the spiral body 2 of each of the scrolls 21 and 22.
1a, 22a is introduced into a compression chamber 24, and the gas fluid compressed in the compression chamber 24 is discharged into a high-pressure space formed on the side of the compression element 2 opposite to the motor. After passing through the motor 4, it is led to a space formed on the side of the motor 4 opposite to the compression element, and is discharged to the outside from a discharge pipe 10 opened in this space.

A circular seal ring receiving portion 51 is provided inside the first bearing housing 5 around the connecting portion between the pin portion 23 of the orbiting scroll 22 and the cylindrical transmission portion 31 of the drive shaft 3. Is formed so that the oil after being supplied to the first and third bearings 71 and 73 is collectively stored in the housing portion 51, and the inside diameter of the housing portion 51 is provided in the housing portion 51. A seal ring 11 having an outer diameter smaller than that of the seal ring 11 and abutting against the back side of the orbiting scroll 22; and an end face of the seal ring 11 opposite to the orbiting scroll side and the seal ring facing the end face. Accommodation section 51
A spring 11a that constantly presses the other end surface of the seal ring 11 against the back side of the orbiting scroll 22 is interposed between the bottom surface of the seal ring 11 and the inner peripheral side of the seal ring 11 by the seal ring 11. The suction pipe 9 is connected to the back pressure chamber 12 facing the center of the back surface of the movable scroll 22 to which the greatest axial load is applied when compressing the gas fluid in the compression chamber 24 at the outer peripheral portion of the movable scroll 22. The low pressure side space 52 of the first bearing housing 5 communicated with the suction port of the first bearing housing 5, and the high pressure oil is filled in the back pressure chamber 12 of the accommodating portion 51 so that the high pressure inside the back pressure chamber 12 is increased. The axial pressure applied to the movable scroll 22 is balanced by the back pressure of the oil.

According to the present invention, in the above structure, a predetermined clearance is formed between the seal ring receiving portion 51 and the seal ring 11 received in the seal ring receiving portion 51. Between the low pressure side outer peripheral surface and the inner peripheral surface of the seal ring accommodating portion 51 opposed to the outer peripheral surface, the oil supplied from the oil supply pump P to the first and third bearings 71 and 73. The injection gap 13 is formed to flow from the low-pressure side space 52 into the compression chamber 24.

That is, in the embodiment shown in the drawing, the injection gap 13 is formed by a clearance which can obtain a required injection amount in the compression chamber 24 of the compression element 2, that is, the injection gap 13
The total cross-sectional area of the clearance formed between the seal ring 11 and the seal ring accommodating portion 51 is smaller than that of the compression chamber 2.
The first and third bearings 71 and 73 are provided on the lower side of the first bearing housing 5 with the oil amount after the first and third bearings 71 and 73 are set. Are gathered, and the back pressure chamber 1 of the seal ring accommodation portion 51 is
An oil return passage 15 is provided for returning oil from the oil collecting chamber 14 communicating with the oil reservoir 2 to the oil reservoir O of the casing 1.
Is formed in such a size that the oil collecting chamber 14 can be filled with oil with respect to the pump capacity of the oil supply pump P. That is, for example, when the inverter control operation of the compression element 2 is performed, the oil from the oil return passage 15 is filled so that the oil from the oil supply pump P fills the oil collecting chamber 14 during the low hertz operation. The cross-sectional area is set so that the oil pumped by the oil supply pump P always supplies oil to the oil collecting chamber 14, that is, the seal ring receiving section 51, regardless of whether a high or low hertz control operation is performed.
It is possible to be filled. The pump capacity of the refueling pump P is set by the larger one of the amount of oil supplied to the first to third bearings 71 to 73 and the amount of oil supplied to each of the compression chambers 24. With this configuration, the oil pumped by the oil supply pump P can always fill the oil collecting chamber 14, that is, the seal ring housing 51.

Next, the operation of the above configuration will be described. At the time of the compression drive of the compression element 2, oil after being supplied to the first and third bearings 71 and 73 from the supply pump P is collected and stored in the seal ring housing 51,
The high-pressure oil in the storage portion 51 is introduced into the back pressure chamber 12 formed by the seal ring 11, and the high-pressure oil in the back pressure chamber 12 applies a back pressure to the center of the back surface of the orbiting scroll 22, This back pressure balances the axial load due to the gas pressure applied to the movable scroll 22 from the compression chamber, thereby preventing the movable scroll 22 from being deformed flexibly.

A part of the oil in the back pressure chamber 12 of the housing part 51 is injected between the low pressure side outer peripheral surface of the seal ring 11 and the inner peripheral surface of the seal ring housing part 51. The gas flows into the low-pressure side space 52 of the compression element 2 from the gap 13 and is supplied to the sliding portions of the spirals 21 a and 22 a forming the compression chamber 24 of the compression element 2. An oil film is formed between the parts, whereby the airtightness in the compression chamber 24 is maintained, and burning is prevented.

In other words, the above configuration has a simple configuration in which the seal ring 11 having a diameter smaller than the inner diameter of the storage portion 51 is interposed in the seal ring storage portion 51 via a predetermined clearance. Oil injection into the low pressure side of the compression element 2 can be performed while preventing the bending deformation of the scroll 22 in the above, maintaining the airtightness in the compression chamber 24 due to the oil injection, and
Since it is possible to prevent burning, it is not necessary to provide an injection passage for performing oil injection on the low pressure side of the compression element 2 as in the related art, and a troublesome hole for forming the injection passage is required. Many processes such as opening work can be eliminated,
Moreover, since no O-ring is required unlike the conventional case, the number of parts can be reduced accordingly, and the overall manufacturing cost can be reduced.

The injection gap 13 is
The cross-sectional area of the oil return passage 15 formed in the compression chamber 24 of the compression element 2 by a clearance for obtaining a required injection amount and provided in the first bearing housing 5 with respect to the pump capacity of the oil supply pump P Since the size of the oil collecting chamber 14 is set to be oil-filled, oil injection is always possible during operation.Also, when the inverter control operation is performed as described above, the oil injection is performed during the low hertz operation. By setting the cross-sectional area of the oil return passage 15 so that the oil from the oil supply pump P fills the oil collecting chamber 14, the oil collecting passage 15 can be used regardless of the high or low hertz control operation. The chamber 14 can always be filled with oil, so that the oil filled in the oil collecting chamber 14 is always injected from the entire area of the injection gap 13. It can be down.

In the above embodiment, the horizontal scroll has been described. However, it goes without saying that the present invention can be applied to the vertical scroll.

[0025]

As described above, according to the first aspect of the present invention, the outer peripheral surface on the low pressure side of the seal ring 11
Because an injection gap 13 is provided between the inner peripheral surface of the seal ring housing portion 51 facing the outer peripheral surface to allow oil supplied from the oil supply pump P to the back pressure chamber 12 to flow into the low pressure side of the compression element 2. , The seal ring housing 5
1 has a simple structure in which the seal ring 11 is disposed via a predetermined clearance.
1 allows the back pressure chamber 12 to be formed to apply a back pressure to the orbiting scroll 22 while performing oil injection from the injection gap 13 to the low pressure side. In addition, the oil injection can be controlled to a desired oil amount by controlling the clearance of the injection gap 13, and the clearance between the seal ring housing portion 51 and the seal ring 11 can be increased without providing an injection passage. It can be formed simply by providing it, so that it can be formed without requiring much processing such as troublesome drilling work for forming an injection passage as in the conventional case. Since there is no need to seal the gap between the ring accommodating portion and the seal ring, the number of components can be reduced without the need for an O-ring, and the overall manufacturing cost can be reduced.

According to the second aspect of the present invention, the injection gap 13 is a clearance for obtaining a required injection amount in the compression chamber of the compression element 2 and an oil return passage provided in the bearing housing 5. 15, the oil return passage 15 for supplying oil to the oil supply point of the bearing housing 5 and collecting the oil collected in the oil collecting chamber 14 from the oil collecting chamber 14 to the oil reservoir O of the closed casing 1 The oil collecting chamber 14 has a cross-sectional area that allows the oil to be filled in the oil collecting chamber 14 with respect to the pump capacity of the pump P. Therefore, the oil pumped up by the oil supply pump P and supplied to the oil supply point is always supplied to the oil collecting chamber. 14, that is, the seal ring accommodating portion 51 is filled, so that high pressure oil filling the back pressure chamber 12 is supplied from the entire area of the injection gap 13 during operation. Always the compression chamber of the reduced element 2, can injection a predetermined amount of oil, therefore, is to enable the prevention of the airtightness of the holding and baking in the compression chamber more reliably.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a main part of a scroll compressor according to the present invention.

FIG. 2 is a longitudinal sectional view showing the entire structure of the scroll compressor.

FIG. 3 is a longitudinal sectional view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Closed casing 2 Compression element 22 Movable scroll 3 Drive shaft 5 Bearing housing 51 Seal ring accommodation part 11 Seal ring 12 Back pressure chamber 13 Injection gap 14 Oil collecting chamber 15 Oil return passage O Oil reservoir P Oil pump

──────────────────────────────────────────────────続 き Continued on the front page (72) Yukihiro Kitagawa 3-12 Chikushinmachi, Sakai City, Osaka Prefecture Daikin Industries Co., Ltd., Sakai Plant Rinkai Plant (72) Inventor Noboru Murata 312 Chikushinmachi, Sakai City, Osaka Prefecture Address Daikin Industrial Co., Ltd. Sakai Plant Rinkai Plant (56) References JP-A-4-365982 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F04C 18/02 311

Claims (2)

(57) [Claims] A drive shaft (3) having a refueling pump (P)
And a movable scroll (2) driven by the drive shaft (3).
2) and a bearing housing (5) for supporting the drive shaft (3). The bearing housing (5) is provided with a seal ring accommodating portion (51). The movable scroll (2) is provided in the accommodation portion (51).
A seal which presses against the back surface of the movable scroll (22) to form a back pressure chamber (12) for applying a back pressure to the back surface of the orbiting scroll (22); In a scroll compressor provided with a ring (11),
Between the oil supply pump (P) and the back pressure chamber (12), between the low pressure side outer peripheral surface of the seal ring (11) and the inner peripheral surface of the seal ring housing portion (51) facing the outer peripheral surface.
A scroll gap provided with an injection gap (13) for allowing oil supplied to the compressor to flow into the low pressure side of the compression element (2). 2. The injection gap (13) has a clearance for obtaining a required injection amount in the compression chamber of the compression element (2), and the bearing housing (5) lubricates a lubrication point of the housing (5). An oil return passage (15) for returning from the oil collecting chamber (14) where the collected oil collects to the oil reservoir (O) of the closed casing (1) containing the compression element (2). 2. The scroll compressor according to claim 1, wherein a cross-sectional area is such that the oil collecting chamber (14) can be filled with oil with respect to a pump capacity of the oil supply pump (P). 3.