JPH0552289U - Rotary compressor - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] Sliding loss between the inner peripheral surface of the bearing portion of the rear head and the drive shaft and seizure, and sliding loss due to thrust between the eccentric part of the drive shaft and the rear head. Reduces baking at the same time. A notch 33b is formed along the inner circumference of the bearing 33a at the bearing base of the bearing 33a of the rear head 33. The floating bush 7 is interposed between the bearing portion 33a and the drive shaft 4 with a predetermined gap therebetween, and a flange portion 71 that engages with the cutout portion 33b provided in the bearing portion 33a is formed at one end of the floating bush 7. [Effect] The relative sliding speed of the drive shaft with respect to the floating bush and the relative sliding speed of the bush and the bearing portion are made slower than the relative sliding speed of the drive shaft with respect to the inner peripheral surface of the bearing portion, and the drive shaft is as much as that. To reduce friction and sliding loss between the floating bush and the bush and the bearing. The relative sliding speed between the thrust surface of the eccentric portion and the flange portion of the floating bush can also be slower than the sliding speed of the thrust surface with respect to the rear head.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a rotary compression system in which a cylinder is provided in a hermetically sealed casing, a compression element including front and rear heads each having a bearing portion, and a motor having a drive shaft. Regarding the machine.

[0002]

[Prior Art]

 Conventionally, in this type of rotary compressor, as shown in FIG. 3, a motor M is disposed above the inside of a hermetically sealed casing C, and a cylinder S having a cylinder chamber S1 is provided on the lower side of the motor M. , A compression element CF composed of a front head F and a rear head R having bearing portions F1 and R1 arranged opposite to each other in the upper and lower parts of the cylinder S, and a roller A rotatably provided in the cylinder chamber S1. While the eccentric portion K1 of the drive shaft K coupled to the motor M is inserted into the roller A, and the eccentric rotation of the roller A accompanying the rotation of the drive shaft K causes the inside of the cylinder chamber S1. The refrigerant gas sucked in is compressed.

In addition, the hard cylindrical bearing cylinders D and E are press-fitted onto the inner peripheral surfaces of the bearings F1 and R1 of the heads F and R, respectively. The drive shaft K is rotatably supported by the bearing cylinders D 1 and E 2.

[0004]

[Problems to be solved by the device]

 However, in the above-described conventional rotary compressor, the bearing cylinders D and E having excellent wear resistance are press-fitted into the bearing portions F1 and R1, but when the drive shaft K rotates, Sliding between the outer peripheral surface of the drive shaft K and the inner peripheral surfaces of the bearing cylinders D and E increases the frictional force to increase the sliding loss, and the friction causes heating to cause seizure. there were. Therefore, in order to reduce this sliding loss, for example, as shown in JP-A-64-56984, the bearing cylinders D and E are provided between the drive shaft K and the bearing portions F1 and R1. The drive shafts K and the bearings are arranged so as to be respectively disposed through a minute gap so that when the drive shaft K rotates, the bearing cylinders D and E also rotate due to frictional resistance with the drive shaft K. The sliding speed with the cylinders D and E is made slower than before to reduce the frictional force and reduce sliding loss and heating due to friction.

However, since the bearing cylinders D and E are straight cylinders and the bearing cylinders D and E are rotatably disposed, the bearing cylinder E is supported at the lower end of the bearing portion R1 on the rear head side. Since a bearing cap is attached and the bearing cylinder 3 has a straight tube shape and does not have a structure for supporting the thrust load of the drive shaft K, the inner circumference of the bearing portion F 1, R 1 is Not only the sliding loss between the surface and the drive shaft K but also the frictional force due to the thrust increases between the lower surface of the eccentric portion K1 of the drive shaft K and the upper surface of the rear head R facing the lower surface, In addition to the large sliding loss, seizure due to friction still occurred, and the sliding loss and seizure due to the thrust could not be reduced by the above-mentioned floating bearing cylinders D and E.

The present invention has been devised in view of the above problems, and is caused by sliding loss and seizure between the inner peripheral surface side of the bearing portion of the rear head and the drive shaft, and thrust between the eccentric portion of the drive shaft and the rear head. It is an object of the present invention to provide a rotary compressor that can reduce sliding loss and seizure at the same time.

[0007]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention provides a compression element including a cylinder 31, a bearing portion 32a and 33a in a hermetic casing 1, and a front head 32 and a rear head 33 arranged in front of and behind the cylinder 31. In a rotary compressor having a motor 2 having a drive shaft 4 and a drive shaft 4, a notch 33b is formed in the bearing base of the bearing 33a of the rear head 33 along the inner circumference of the bearing 33a. The floating bush 7 is interposed between the bearing portion 33a and the drive shaft 4 through a predetermined gap, and a flange portion 71 that engages with the cutout portion 33b is formed at one end of the floating bush 7.

[0008]

[Action]

 When the drive shaft 4 rotates, the floating bush 7 is moved in the same rotation direction by the frictional resistance due to the rotation of the drive shaft 4, and the relative sliding speed of the drive shaft 4 with respect to the floating bush 7 and the bush 7 are changed. The relative sliding speed with respect to the bearing portion 33a becomes slower than the relative sliding speed with respect to the inner peripheral surface of the bearing portion 33a of the drive shaft 4, and the drive shaft 4 and the floating bush 7 and Friction and sliding loss between the bush 7 and the bearing sleeve 33a are reduced. Furthermore, since the thrust surface of the eccentric portion 41 is received by the flange portion 71 of the floating bush 7, the flange portion 71 is moved in the same rotational direction by the frictional resistance due to the rotation of the eccentric portion 41, and the thrust surface is The relative sliding speed between the flange portion 71 and the flange portion 71 is also slower than the relative sliding speed of the thrust surface with respect to the rear head 33, and friction and sliding loss are reduced accordingly. Therefore, by interposing the floating bush 7, sliding loss and seizure between the inner peripheral surface side of the bearing portion 33a of the rear head 33 and the drive shaft 4, and the eccentric portion 41 of the drive shaft 4 and the rear head 33 are caused. Sliding loss and seizure due to the thrust of are simultaneously reduced.

[0009]

【Example】

 An embodiment of a rotary compressor according to the present invention will be described below with reference to the drawings. In the rotary compressor shown in FIG. 1, a motor 2 including a rotor 21 and a stator 22 is built in an upper portion of a closed casing 1 having an oil sump 1a at the bottom, and a cylinder 2 is provided below the motor 2. 31 and a compression element 3 consisting of a front head 32 and a rear head 33 arranged at the upper and lower positions of the cylinder 31, and the front head 32 and the rear head 33 are provided with bearing portions 32a, 33a extending in the vertical direction. The drive shaft 4 is supported by the bearings 32a and 33a so that the upper end of the drive shaft 4 is connected to the motor 2, while the roller 34 is fitted into the eccentric portion 41 of the drive shaft 4.

Further, the cylinder 31 is provided with a suction hole 31b for sucking low-pressure gas refrigerant into the cylinder chamber 31a, and the front head 32 is formed with a discharge hole 32b for discharging the compressed gas refrigerant. The muffler 5 is attached to form the discharge chamber 51 by the muffler 5, and the low pressure gas refrigerant is introduced from the suction hole 31b into the cylinder chamber 31a by the rotation of the roller 34 accompanying the rotational driving of the motor 2. The suctioned gas refrigerant is compressed by the rotation of the roller 34, and the compressed gas refrigerant is discharged into the discharge chamber 51 from the discharge hole 32b. The inner primary discharge space 6 is made to discharge. A bearing tube 32c made of hard metal is fixed to the inner surface of the bearing portion 32a of the front head 32 by press fitting.

Thus, the present invention is the rotary compressor described above, wherein the bearing base portion of the bearing portion 33a of the rear head 33 is formed with an annular cutout portion 33b along the inner circumference of the bearing portion 33a. The floating bush 7 is interposed between the bearing portion 33a and the drive shaft 4 with a predetermined gap, and a flange portion 71 is formed at one end of the floating bush 7 to engage with the cutout portion 33b. .

Specifically, as shown in FIG. 2, the floating bush 7 made of hard metal is inserted into the bearing portion 33a of the rear head 33 along the inner peripheral surface of the bearing portion 33a, and The drive shaft 4 is inserted on the inner peripheral side of the floating bush 7, and a gap a is formed between the inner peripheral surface of the bearing portion 33a and the outer peripheral surface of the floating bush 7. The gap b is formed between the drive shaft 4 and the drive shaft 4. Further, the flange that extends outward in the radial direction on the bearing base side of the floating bush 7, receives the entire thrust surface of the eccentric portion 41 of the drive shaft 4, and receives a part of the lower surface of the roller 34. The notch portion 33b is formed in the bearing base portion of the bearing portion 33a so that the flange portion 71 engages with the portion 71.

A gap c is formed between the cutout portion 33b and the side surface of the flange portion 71, and the average size of the gap c in the radial direction is defined between the floating bush 7 and the bearing portion 33b. It is made larger than the size of the gap b. By doing so, even if the floating bush 7 moves in the radial direction and the gap b disappears, the gap c can be secured, so that the gap c supplies oil to the inner circumferential side of the roller 34 in the cylinder chamber 31a. The oil sump can always form an oil sump.

As described above, according to the rotary compressor of the present invention, since the floating bush 7 is interposed between the bearing portion 33a of the rear head 33 and the drive shaft 4, the drive shaft 4 is When the rotating shaft rotates, the floating bush 7 moves in the same rotation direction due to the frictional resistance due to the rotation of the drive shaft 4, so that the relative sliding speed of the drive shaft 4 with respect to the floating bush 7 and the bush 7 and the bearing portion 33a. The relative sliding speed with respect to the drive shaft 4 can be made slower than the relative sliding speed with respect to the inner peripheral surface of the bearing portion 33a of the drive shaft 4, and only the drive shaft 4, the floating bush 7 and the bush 7 can be It is possible to reduce friction and sliding loss with the bearing portion 33a. Further, since the thrust surface of the eccentric portion 41 is received by the flange portion 71 of the floating bush 7, the flange portion 71 moves in the same rotation direction due to the frictional resistance due to the rotation of the eccentric portion 41, and thus the thrust surface. Since the relative sliding speed between the rear face 33 and the flange portion 71 can also be made slower than the relative sliding speed of the thrust surface with respect to the rear head 33, friction and sliding loss can be reduced accordingly. Therefore, by interposing the floating bush 7, the sliding loss and seizure between the inner peripheral surface side of the bearing portion 33a of the rear head 33 and the drive shaft 4 and the eccentric portion 41 of the drive shaft 4 and the rear head are caused. It is possible to simultaneously reduce sliding loss and seizure due to thrust with 33.

Further, since the flange portion 71 formed on the floating bush 7 is engaged with the cutout portion 33b, it is possible to prevent the floating bush 7 from dropping downward, and to stop the floating bush 7 from being stopped. It is not necessary to hold it by another member such as.

Further, since the oil sump can always be formed by the gap c, sufficient oil can be supplied to the thrust surface, so that seizure can be prevented more effectively.

[0017]

[Effect of the device]

 As described above, in the rotary compressor of the present invention, the notch portion 33b along the inner circumference of the bearing portion 33a is formed in the bearing base portion of the bearing portion 33a of the rear head 33, and at the same time, the bearing portion 33a and the driving portion 33a are driven. Since the floating bush 7 is interposed between the shaft 4 and the shaft 4 through a predetermined gap, and the flange portion 71 that engages with the notch 33b is formed at one end of the floating bush 7, the drive shaft 4 rotates. At this time, the floating bush 7 is moved in the same rotation direction by the frictional resistance due to the rotation of the drive shaft 4, and the relative sliding speed of the drive shaft 4 with respect to the floating bush 7 and the bush 7 and the bearing portion 33a. The relative sliding speed can be made slower than the relative sliding speed of the drive shaft 4 with respect to the inner peripheral surface of the bearing portion 33a, and the drive shaft 4 and the floating bush 7 and the bush 7 and the bearing portion can be correspondingly slowed down. 3a friction and is of the sliding loss can be reduced between. Furthermore, since the thrust surface of the eccentric portion 41 is received by the flange portion 71 of the floating bush 7, the flange portion 71 is moved in the same rotational direction by the frictional resistance due to the rotation of the eccentric portion 41, and the thrust surface The relative sliding speed with respect to the flange portion 71 can also be slower than the relative sliding speed of the thrust surface with respect to the rear head 33, so that friction and sliding loss can be reduced accordingly. Therefore, by interposing the floating bush 7, sliding loss and seizure between the inner peripheral surface of the bearing portion 33a of the rear head 33 and the drive shaft 4 and seizure, and the eccentric portion 41 of the drive shaft 4 and the rear head. It is possible to reduce sliding loss and seizure due to thrust with 33 at the same time.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a rotary compressor of the present invention.

FIG. 2 is an enlarged sectional view of a main part of the rotary compressor of the present invention.

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

[Explanation of symbols]

 1 Airtight casing 2 Motor 3 Compression element 31 Cylinder 32 Front head 32a Bearing part 33 Rear head 33a Bearing part 33b Notch part 4 Drive shaft 7 Floating bush 71 Flange part

Claims (1)

[Scope of utility model registration request] 1. A motor having a hermetic casing 1 having a cylinder 31, bearings 32a and 33a, a compression element 3 including a front head 32 and a rear head 33 disposed in front of and behind the cylinder 31, and a drive shaft 4. In the rotary compressor having 2 inside, the bearing portion 33a of the rear head 33 is provided with a notch portion 33b along the inner circumference of the bearing portion 33a and the bearing portion 33a.
The floating bush 7 is interposed between the drive shaft 4 and the drive shaft 4 through a predetermined gap, and a flange portion 71 that engages with the notch 33b is formed at one end of the floating bush 7. Compressor.