JPH048639B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a thrust bearing mounting structure for a scroll compressor, and particularly to a thrust bearing mounting structure suitable for obtaining a thrust bearing with a simple shape.

[Background of the invention]

A hermetic scroll compressor will be described as an example of a scroll fluid machine.

As shown in Fig. 1, the structure of a conventional hermetic scroll compressor includes an orbiting scroll 1, a fixed scroll 2, and a flank portion 3a, which perform relative orbiting motion.
The scroll compression mechanism includes a drive shaft 3 having a frame 4, a motor 5 for driving the scroll compression mechanism, and an airtight container 6 housing these components.

The orbiting scroll 1 has a spiral wrap 1b on the end plate 1a, and on the back side has an anti-rotation mechanism 1C for preventing rotation and an orbiting bearing 1d into which the crank portion 3a of the drive shaft is inserted.

The fixed scroll 2 also has a wrap 2b on the end plate 2a.

The fixed scroll and the orbiting scroll are combined with each other with their laps facing inward, and when the motor rotates, the crank part of the drive shaft and the anti-rotation mechanism perform a relative orbiting motion, and the scroll is formed by the laps of both scrolls and the end plate. As the space moved toward the center, its volume decreases. As a result, the inhaled gas is compressed and discharged.

A force acts between the orbiting scroll and the fixed scroll due to the compression of gas, which tends to separate the two scrolls. In order to prevent this, the pressure in the space (intermediate chamber) 7 formed by the orbiting scroll head plate and the frame is maintained at a pressure between the suction pressure and the discharge pressure.

The drive shaft 3 is provided with an oil supply hole 3b, through which lubricating oil from the lower part of the closed container 6 is supplied to each sliding portion.

The oil supplied to the bearing 1d of the orbiting scroll is
It flows out into the intermediate chamber via the bearing. For this reason, the pressure at the end face of the crank portion 3a of the drive shaft 3 may become lower than the pressure at the bottom of the closed container. As a result, a thrust force is generated on the drive shaft, and the end surface 3c of the shaft
Then, the boss end face 1e of the orbiting scroll bearing 1d comes into contact with each other, causing problems such as increased mechanical loss and wear.

The above problem is caused by the diameter of the balance weight attachment part 3d of the drive shaft being partially different from the boss diameter of the swing bearing, as shown in Fig. 2, and the entire surface of the bearing boss end face 1e is covered by the upper surface of the attachment part 3d. This is because the outer diameter of the end face 3c of the drive shaft rotates across the boss end face 1e of the slewing bearing without being a thrust bearing. This problem can be solved by increasing the diameter of the balance weight attachment part 3d so that it is located outside the end face 1e of the pivot boss, as shown in FIG. 3, but this increases the material of the drive shaft and imposes restrictions on processing. Furthermore, the diameter of the mounting portion of the balance weight also increases, causing a problem that the balance weight becomes larger.

Incidentally, related devices of this type include, for example, Japanese Patent Laid-Open Nos. 55-160192 and 57-76201.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a thrust bearing device for a scroll compressor that can be easily installed and is equipped with a thrust bearing member that provides a thrust bearing over the entire end face of an orbiting scroll bearing boss in order to solve the above-mentioned problems in conventional scroll compressors. It is about providing.

[Structure of the invention]

In order to achieve the above object, a thrust bearing device for a scroll compressor according to the present invention has an orbiting scroll and a fixed scroll consisting of an end plate and a spiral wrap standing upright on the end plate, and a crank portion that gives an orbiting motion to the orbiting scroll. drive shaft,
Consisting of an anti-rotation mechanism and a frame that houses them, both scrolls are assembled with the wraps facing inward, and the space formed by each wrap and end plate decreases in volume as it moves toward the center of the scroll. The structure is such that both scrolls move relative to each other, and the crank part of the drive shaft is inserted into the bearing boss provided on the opposite side from the lap of the orbiting scroll, so that the end face of the drive shaft and the end face of the mounting part of the balance weight are on the same plane or In a scroll compression mechanism in which a balance weight is attached to the upper end of the drive shaft so that the drive shaft end face is slightly concave, an eccentric The thrust bearing member is provided with a thrust bearing surface that contacts the entire surface of the lower end surface of the hole and the bearing boss, and the eccentric hole of the thrust bearing member is fitted into the crank portion. Further, the eccentric hole of the thrust bearing member having the eccentric hole is engaged with the crank part, and the outer peripheral part is partially stopped by a balance weight provided on the drive shaft to prevent rotation of the thrust bearing member. It is something to do.

[Embodiments of the invention]

Embodiments of the present invention will be described with reference to FIGS. 4 to 6.

FIG. 4 shows an example in which the present invention is applied to a hermetic scroll compressor.

A thrust bearing material 9 is installed on the end surface 3c of the drive shaft. As shown in FIGS. 5 and 6, the thrust bearing material 9 has an eccentric hole 9a that is approximately equal to the eccentricity of the crank, and this eccentric hole is engaged with the crank portion 3a of the drive shaft 3. On the other hand, the outer circumference 9b of the thrust bearing member is partially guided by the inner diameter portion 8b of the balance weight. Further, the outer diameter of the thrust bearing member 9 is slightly larger than the outer diameter of the mounting portion 8a of the balance weight.

Further, the end face 3c of the drive shaft and the end face of the balance weight mounting portion 8a are installed on the same plane or in a position where the end face of the drive shaft is slightly recessed.

According to this structure, when a thrust force acts on the drive shaft and the shaft moves, the thrust bearing member 9
Since the entire surface is in contact with the boss end surface 1e of the slewing bearing,
It can prevent wear and galling of the boss.

Furthermore, in such a state, the thrust bearing member 9 tries to rotate around the center of the crank part, that is, the center 9c of the eccentric hole, but the outer periphery 9a of the thrust member is guided by the inner diameter of the balance weight concentric with the center 9d. rotation can be prevented.

[Effects of the Invention] According to the present invention, by arranging a simple thrust bearing member having an eccentric hole on the upper end of the drive shaft without any special processing, the end face of the slewing bearing boss can be fully thrust-beared. Furthermore, by simply engaging the eccentric hole with the crank portion of the drive shaft, it is possible to achieve the effect of preventing rotation of the thrust bearing member.

By installing this thrust bearing member, it is possible to prevent wear and galling on the end face of the swing bearing boss due to the thrust force of the drive shaft.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the structure of a conventional scroll compressor. FIG. 2 is a sectional view showing an end face of a conventional drive shaft, and FIG. 3 is a sectional view showing an example of an improved proposal. FIG. 4 is a sectional view showing the structure of the scroll compressor of the present invention. FIG. 5 is a sectional view showing a state in which the thrust bearing of the present invention is installed. FIG. 6 is a top view showing a state in which the thrust bearing of the present invention is installed. 1...Orbiting scroll, 1a...End plate, 1b...
... Wrap, 1c... Rotation prevention mechanism, 1d... Rotating bearing, 1e... Swivel bearing boss end face, 2... Fixed scroll, 2a... End plate, 2b... Wrap, 3...
... Drive shaft, 3a ... Crank part, 3b ... Oil supply hole, 3c ... Drive shaft end face, 3d ... Balance weight mounting part, 4 ... Frame, 5 ... Motor, 6
... Airtight container, 7 ... Intermediate chamber, 8 ... Balance weight, 8a ... Balance weight attachment part,
8b...Balance weight inner circumference, 9...Thrust bearing material, 9a...Eccentric hole, 9b...Outer circumference, 9c...
... Center of eccentric hole, 9d ... Center of thrust bearing material.

Claims (1)

[Claims] 1. An orbiting scroll and a fixed scroll consisting of an end plate and a spiral wrap standing upright on the end plate;
It consists of a drive shaft with a crank part that gives an orbiting motion to the orbiting scroll, an anti-rotation mechanism, and a frame that houses them. Both scrolls are assembled with the laps facing inward, and the space formed by each lap and end plate is the scroll. The crank part of the drive shaft is inserted into the bearing boss provided on the opposite side of the wrap of the orbiting scroll, and the crank part of the drive shaft is In a scroll compression mechanism in which a balance weight is attached to the upper end of the drive shaft so that the end face and the end face of the mounting part of the balance weight are flush with each other or the end face of the drive shaft is slightly recessed, the balance weight is placed under the bearing boss of the orbiting scroll. A thrust bearing member having an eccentric hole and a thrust bearing surface that contacts the entire surface of the lower end surface of the bearing boss is arranged between the end face and the end face of the mounting part of the balance weight, and the eccentric hole of the thrust bearing member is connected to the crank part. A thrust bearing device for a scroll compressor, characterized in that it is fitted and installed. 2. A patent claim characterized in that the eccentric hole of a thrust bearing member having an eccentric hole is fitted into the crank part, and the outer circumference is partially stopped by a balance weight provided on the drive shaft to prevent rotation of the thrust bearing member. A thrust bearing device for a scroll compressor according to item 1.