JPS5918287A - Scroll compressor - Google Patents

Abstract

PURPOSE:To keep oil in the oil reservoir of the scroll compressor in constant by a method wherein an oil returning pipe, communicating an Oldham's chamber with the oil reservoir, is provided so as to be capable of returning the oil in the Oldham's chamber into the oil reservoir at all times. CONSTITUTION:The pressure of the oil reservoir 23 is lower than the same of a motor chamber 19, therefore, the pressure difference between the Oldham's chamber 11 and the oil reservoir 23 is smaller than the same between the Oldham's chamber 11 and the motor chamber 19. Accordingly, the pressure difference between both ends of the oil returning pipe 28 becomes smaller than the same in a conventional compressor. The oil level 29 of the oil returning pipe 28 is not arriving at the Oldham's chamber 11 and the oil level 29 is stabilized even if the oil is returned from the Oldham's chamber 11, therefore, the amount of oil in the oil reservoir 23 may be kept in constant at all times.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a treatment device for oil flowing into an Oldham chamber from a bearing of a scroll compressor used in an air compressor, a refrigerant compressor, etc. Before entering into the description of this invention ,
The principle of a scroll compressor will be briefly described.

The basic elements of a scroll compressor are shown in Figure 1, where l is a fixed scroll, 2 is an oscillating scroll,
5 is a compression chamber formed by a gap between the fixed scroll and the oscillating scroll 2, and 0 is the center of the fixed scroll.

The fixed scroll Ijd and the oscillating scroll 2 have a spiral 2 with the same shape and opposite winding direction, and the shape of this spiral is a combination of involutes, circular arcs, etc. By combining these spirals, it is possible to form both spirals. A compression chamber 5 is formed in between.

Next, the operation will be explained. In Fig. 1, the fixed scroll 1 is stationary with respect to space, and the oscillating scroll 2 is combined with the fixed scroll 1 as shown in the figure, so that its posture does not change with respect to space, that is, it rotates on its axis. The fixed scroll 1 rotates around the center 0 without moving, that is, swings, and moves as shown in Fig. 1 a, b, (!, d, @. With the movement, the volumes of the compression chambers 5 &

Next, a specific example of a conventional scroll compressor will be described with reference to FIG.

FIG. 2 shows a specific embodiment in which a scroll compressor is applied to an air conditioner or an air compressor, such as a refrigerator 1, and is constructed as a compressor for a gas such as fluorocarbon.

In the figure, 1 is a fixed scroll, 2 is an oscillating scroll, 3 is an oscillating scroll 20 plywood, and has a diametrical groove 3a on the back surface. 4 is an oscillating scroll shaft, 5 is an engineering compression chamber, 6 is a suction part of the compression chamber 5, 7 is a ring attached slightly apart from the back of the oscillating scroll base plate 3, and 8 is the rotation of the oscillating scroll 2 A ring-shaped Oldham joint that prevents vibrations and swings, with protrusions arranged in a cross shape on the upper and lower surfaces of each other.
+gb beggar. Reference numeral 9 indicates a thrust bearing that supports the back surface of the swinging scroll base plate 3; 10 indicates a bearing support to which the fixed scroll l is fixed with bolts, etc.; and is fixed to the shell by a method such as press fitting, which will be described later; and 11 indicates a base plate. 3 and an Oldham chamber formed between the ring 7 and the bearing support 10; 12 an oil return hole formed in the bearing support 10 and communicating with the Oldham chamber 11 and a motor chamber to be described later; 13a an oil return hole formed in the bearing support 10; Attached is a motor stator, 13b is a motor rotor, 14 is a crankshaft, 15 is an oil hole provided eccentrically in the crankshaft 14, and 16 is provided eccentrically in the crankshaft 14, and is fitted into the oscillating scroll shaft 4A. Swing bearing, 17 is the main bearing that fits into the upper part of the crankshaft 14, 18 is also the crankshaft 1
4 Motor side bearing that fits with the intermediate part, 19 is the bearing support lO
20 is an fp 1 balance fixed to the upper part of the motor rotor 13b, 21 is the same (a second balance fixed to the lower part of the motor rotor 13b, 22
The bearing support 10 is fixed and the whole compressor is sealed with a shell,
23 is an oil reservoir provided at the bottom of the shell 22, 24 is a suction pipe communicating with the motor chamber 19 from the outside of the shell 22, 25 is a so-called air gap between the motor stator 13a and the motor rotor 13b, and 26 is a bearing support 10 and the shell. 22 is a constant flow path provided partially between the fixed scrolls 1 and 27;
Gas is discharged to the outside of the J9 shell 22 at approximately the center of the
This is the second discharge pipe.

The operation of the scroll compressor configured in this way will be explained.

First, when the motor stator 13a is energized, the motor rotor 13b generates torque to drive the crankshaft 14'l. When the crankshaft 14 starts rotating 2, the crankshaft 14
Torque is transmitted to the oscillating scroll shaft 4, which is fitted in a oscillating bearing 16 provided eccentrically at the center of the axis, and the oscillating scroll 2 is guided by the Oldham joint 8 and performs two oscillating movements, as shown in FIG. Perform two compression operations as shown.

The gas enters the motor chamber 19 from the suction pipe 24 as indicated by the solid line in the figure, and passes through the air cap 25 to the motor stator 13&? and motor rotor 13b4, oil sump 2
The direction is reversed at the upper part of 3, and the flow j2!26Y is sucked into the rear suction chamber 6, taken into the compression chamber 5, and then the crankshaft 1
4 rotates, the discharge pipe 27 is sent inward and installed in the center of the fixed scroll 1. J: Discharged.

Next, the oil supply system will be explained. The oil accumulated in the oil sump 23 is sucked up from the lower end of the crankshaft 14 by the pumping action of the constant oil hole 15, which is eccentrically drilled in the crankshaft 14, as shown by the broken line arrow in the figure. through which it is supplied to the swing bearing 16, main bearing 17, and motor side bearing 18.
After passing through these, it is supplied to the slant bearing 9 to lubricate the thrust bearing surface, and then discharged into the Oldham chamber 1. 1 oil accumulated in Oldham room 11 yen is oil return hole 12
After passing through and falling into the motor room 19, the air gap 2
5Y and is returned to the oil sump 23.

Na? , the oscillating scroll 2 accompanying the rotation of the crankshaft 14
The rocking motion of the compressor tends to cause vibrations due to unbalanced forces in the entire compressor. Since the balance 2° and the second balance 21 can balance the rotation around the crankshaft 14, the compressor can be operated without abnormal vibration.

In the above-described conventional scroll compressor configured with J:5, a gap exists between the back surface of the base plate 3 of the oscillating scroll 2 and the ring 7. This is due to the following reasons.

If the link 7χ is brought into contact with the back of the base plate 3, mechanical loss will increase unnecessarily in this part, and it will be necessary to supply oil for lubrication, but this lubricating oil is unnecessarily sucked into the suction chamber 6 and discharged into the discharge pipe 27.J along with the gas.
: There is a risk that it will be carried away to the outside of the compressor and heated up to 7°C. Therefore, as described above, a predetermined gap must be provided between the back surface of the base plate 3 and the ring 7.

Further, as shown in FIG. 3, the ring 7 is provided with a notch 7IL in order to avoid interference with the bumper 8b of the Oldham joint 8, and this portion also becomes a gap. Incidentally, although the gas inflow path is as described above, the pressure within the gas inflow path generally decreases gradually from the mud toward the downstream.

Therefore, in the conventional scroll compressor shown in FIG. 2, the pressure decreases in the order of suction pipe 24, motor chamber 19, flow path 26, and suction chamber 6. Considering the pressure in the Oldham chamber 11 yen, the Oldham chamber 11 has a relatively high pressure in the motor chamber 1.
The Oldham chamber 11 communicates with the oil return holes 11IC and 11IC, J, and at the same time communicates with the relatively low pressure suction chamber 6 through the above-mentioned gap L2.The Oldham chamber 11 has an intermediate pressure between the motor chamber 19 and suction chamber 6 It is K to show that.

Therefore, the gas in the motor chamber 19 inevitably flows into the Oldham chamber 11 where the pressure is lower. Although this inflow is small,
As the absolute amount of gas flowing into the suction pipe 211.1 increases, the pressure difference between the motor chamber 19 and the Oldham chamber 1 also increases.
The flow into Oldham's room increases by 7] by 0.

In this way, when oil flows into the Oldham chamber through the oil return hole 12, the oil in the Oldham chamber passes through the oil return hole 12 and is discharged to the motor chamber.
1 may be filled with oil. This 157. In the r state, the Oldham joint 8 is moved in oil Vr, T
This causes a large resistance and the compressor input increases t2! cormorant. In addition, the oil in the Oldham chamber 11 flows into the suction chamber 6 through the gap between the back surface of the base plate 3 and the ring 7, and the oil is not returned to the oil sump 23, resulting in the amount of oil in the oil sump 23. is impaired, making it impossible to drive safely.

This invention was developed in view of the above-mentioned drawbacks, and by providing an oil return pipe that communicates with the Oldham chamber and the oil sump,
It is stipulated that you can always lure to the oil sump in the Oldham room,
The objective is to provide a highly reliable compressor that does not reduce the amount of oil in the oil reservoir.

Hereinafter, one embodiment of the present invention will be explained with reference to FIG.
In FIG. 4, reference numeral 28 denotes a temporary oil pipe having one end opened into the Oldham chamber 11 and the other end opened into the oil sump 23, communicating the two;
29 is the oil level in the oil return pipe 28. In this figure, the same or equivalent parts as in FIG. 2 are designated by the same reference numerals as in FIG. 2, so their explanation will be omitted.

In the constant scroll compressor 3 constructed in this way, the pressure in the oil sump 23 is set to be lower than the pressure in the motor chamber 19, and due to the pressure difference between the Oldham chamber 11 and the motor chamber 19, the pressure in the oil sump 23 is lower than that in the motor chamber 19. The pressure difference between is small. Therefore, oil return pipe 28
The pressure difference between both ends of the oil return hole 1 of a conventional scroll compressor is
It is smaller than the pressure difference between both ends of 2.

One end of the oil return pipe 28 on the oil sump side is open to the oil level, and the oil level 29 inside the oil return pipe 28 is as shown in Figure 4.
The oil level at the oil sump 23 yen rises by a height corresponding to the pressure difference between both ends. However, as mentioned above, the pressure difference between both ends of the oil return pipe 28 is relatively small. Since there is a sufficient distance between the oil level in the oil reservoir and the Oldham chamber, the oil return pipe 28
The oil level 29 inside does not reach the Oldham chamber 11, and even if the oil is returned from the Oldham chamber 11, the oil level 29 remains almost stable. Therefore, the oil discharged into the Oldham chamber 11 will not accumulate in the Oldham chamber 11.

The amount of oil in the oil reservoir 23 is not lost, and stable operation can be performed.

FIG. 5 shows a further development of this invention in which the open end of the oil return pipe shown in FIG. FIG. 2 is a partial perspective view of a scroll compressor. In the scroll compressor constructed in this way, the Oldham joint 8 is designed to reciprocate as shown by the arrow in the figure, and the oil in the groove 10a is pumped by the pumping action of the thruster 8a, and the oil returns to the oil return pipe. 2
It will be discharged into 8. Therefore, the oil can be returned to the oil reservoir 23 more reliably.

Figure 6 shows a further development of this invention.
The open end of the oil return pipe 28 on the oil reservoir side shown in FIG.

In general, the oil in the oil reservoir has a rotational motion according to the rotations iC and J of the crankshaft 14, as shown in FIG. When the oil return pipe 28 is opened to the downstream side of such a flow, a negative pressure χ is created near the opening end.
As a result, the oil in the oil return pipe 28 is likely to be sucked.

Particularly, as shown in FIG. 6d, if seven layers 30x are provided at the open end, the negative pressure described above will increase, and the oil in the oil return pipe 28 will be further sucked.

As described above, according to the present invention, by providing the oil return pipe that communicates the Oldham chamber and the oil sump, the oil in the Oldham chamber is always returned to the oil sump, and the oil in the oil sump can be maintained. Therefore, it can provide a highly reliable compressor with excellent effectiveness.

[Brief explanation of the drawing]

Fig. 1 is a diagram of the operating principle of a scroll compressor, Fig. 2 is a sectional view of a conventional scroll compressor, Fig. 3 is a partial perspective view of a conventional scroll compressor, and Fig. 4 is an illustration of an embodiment of the present invention. The sectional view, FIG. 5, and FIG. 6 are perspective views showing another embodiment of the present invention. l t7. Fixed scroll, 2 is an oscillating scroll, 5 is a compression chamber, 8 is an Oldham joint, 10 is a bearing support, 11 is an Oldham chamber, 12 is an oil return hole, 14 is a crankshaft, 19 is a motor chamber, 23 is an oil reservoir, 28 is an oil return pipe. Agent Shin Kuzuno - (1 other person) f 1 Figure (e) Spear 2 Figure Noah ta Zuga 4 Figure 5 Figure/l

Claims (4)

[Claims] (1) A fixed scroll and an oscillating scroll each having a spiral shape, and a compression chamber Y being formed between the two volutes by combining these volutes with each other; an Oldham joint R that compresses fluid by inhaling it, a crankshaft, a thrust bearing that supports the oscillating scroll X, a frame that supports the crankshaft, a motor that drives the crankshaft, and a back surface of the scroll. In a high scroll compressor, the Oldham chamber is formed between the frame and the Oldham chamber, the shell accommodates all the members, and an oil reservoir is provided at the bottom of the shell. A scroll compressor comprising a flow path 2 that communicates with the oil reservoir. (2) One end of the circulation path that communicates the Oldham chamber and the oil reservoir on the Oldham chamber side is formed in the frame and opens into an Oldham groove into which a part of the Oldham joint is fitted and slides. The scope of the patent claims w,
Scroll compressor according to item 1. (3) A patent claim characterized in that one end on the oil reservoir side of the flow passage communicating the Oldham chamber and the oil reservoir is opened in the downstream direction of the oil flow generated in the oil reservoir by the rotation of the crankshaft. Scroll compressor according to the first item. (4) A flared portion is formed at one end on the oil sump side of the flow path that communicates the Oldham chamber with the oil sump so as to be substantially orthogonal to the direction of oil flow generated in the oil sump due to rotation of the crankshaft.
A scroll compressor according to claim 3, characterized in that: