JPS58148291A - Scroll compressor - Google Patents

Abstract

PURPOSE:To reduce frictional loss by using the upper and lower end-faces of a halance weight as thrust bearing surfaces, where the balance weight consolidated with the spindle is set between the thrust bearing of a revolving scroll boss and the thrust bearing part of the main bearing. CONSTITUTION:A balance weight 4a consolidated with the spindle 4 is set between the thrust bearing part 20b of a revolving scroll boss bearing 20 and the thrust bearing part 8a of the main bearing 8, and its upper 4c and lower 4e end-faces are used as thrust bearing surfaces. Accordingly either of the upper 4c or lower 4e end-faces of this balance weight 4a works as slide contact surface according to if the thrust force Fu acting on the spindle 4 is directed positive or negative. Thereby slide contact in the thrust direction is eliminated and production of friction dust can be suppressed, so that the frictional loss is reduced to provide enhancement of the mechanical efficiency of the compressor. Thus the reliability around the bearings can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of an orbiting scroll boss bearing protruding from the back surface of an orbiting scroll member of a scroll compressor for a refrigeration device such as an air conditioner. , will be explained with reference to FIGS. 2 and 3.

The first figure shows the overall structure of a closed type two-spool seven-stroke compressor for four air conditioners. This compressor consists of a fixed scroll member 2 and an orbiting scroll member 3, which are held in a compression section 1LI'JA, a self-1i prevention member (not shown) that prevents rotation of the orbiting scroll 3, a main shaft 4, and a main shaft 4. It is composed of three bearing parts (orbiting scroll boss part bearing 7, main bearing 8, and auxiliary bearing 9) that support the motor, an electric motor 10, a frame 17, and the like. These components are housed inside the closed container 1. Figure 1 is! F close IN! This is an example of a high-pressure chamber type structure in which the inside of the chamber is in an atmosphere of discharge pressure (high-pressure side pressure).

The prior art will be explained according to the flow of refrigerant gas and lubricating oil.

The low-temperature, low-pressure refrigerant gas is guided from the suction pipe 11 and reaches the suction passage 2a within the fixed scroll. The refrigerant gas that has reached the compression support part is caused by the revolving movement of the orbiting scroll 3, which is prevented from rotating, so that the closed space formed by both scrolls gradually becomes smaller and moves to the center of the scroll 9. The underarm refrigerant gas is discharged from the central discharge hole 16 with increased pressure. The discharged high-temperature, high-pressure refrigerant gas fills the upper space 13 in the sealed container 41 and the space 15 around the t# machine body p, and is guided to the outside via the discharge pipe 12. (This high pressure 9 discharge pressure is indicated by the symbol Pd.) On the other hand, a space 14 surrounded by the back of the orbiting scroll member and the 7 frames 11 (this is called a back pressure chamber) is formed by both orbiting and fixed scrolls. The gas force in the thrust direction due to the gas pressure in the plurality of sealed spaces (this force becomes a separation force that tries to push the orbiting scroll member 3 downward).

) K To counteract this, a pressure (indicated by a symbol) between the suction pressure (low pressure side pressure) and the discharge pressure acts. Lubricating oil 8 to explain the flow of lubricating oil using Figure 2 as well as Is1 diagram
is placed in the lower part of the sealed container A1.

The lower end of the main shaft 4 is immersed in oil at the bottom, and the upper part of the main shaft is provided with an eccentric shaft portion 4d, which is rotated through an orbiting scroll boss bearing I to rotate the °C scroll pressure m element. It is engaged with the scroll member 3. A single vertical hole 5 for supplying oil to each bearing part is formed in the main shaft 4 from the main shaft 'F4 to the upper four surfaces 4b of the main shaft. A balance weight part 4a is engaged with and integrated with the main shaft 4 at the upper part of the main bearing, which faces the distal end surface of the orbiting scroll boss part 3a, around the eccentric shaft part 4do.

The main shaft F end immersed in lubricating oil 8 is in an atmosphere of high discharge pressure pd, while the area around the downstream orbiting scroll boss bearing is in an atmosphere of intermediate pressure Pm.
4, the lubricating oil 8 at the bottom of the container rises inside the eccentric vertical hole 5 due to the (Pd-Pm)O pressure difference. Furthermore, due to the rotation of the main shaft 5, centrifugal force acts on the oil in the eccentric vertical hole 5, further increasing the amount of oil supplied to each bearing. In this way, each bearing is supplied with oil by the eccentric hole oiling method and the differential pressure oiling method. The lubricating oil 8 that has ascended through the eccentric vertical hole 5 is transferred to the auxiliary bearing 9 and the main bearing 8, and reaches the upper space 18 of the eccentric shaft portion 4d. The lubricating oil in the upper space 18 is supplied to the bearings 1i4i1 of the swing Shumir boss bearing 1.
19 and drains the oil toward the tip of the boss man. Furthermore, 1ml? The flow of oil 8 is shown by a dashed line with an arrow. The main bearing 8 receives a thrust load due to the weight of the rotor of the electric motor 10, the main shaft 4, etc.
Be prepared. The orbiting scroll boss bearing 1 is a journal bearing (Speo41I) because the driving force acts in the radial direction.
Il-receiving) is closed.

Next, the problems of the prior art will be explained using the s2 diagram and the M3 diagram. A force in the thrust direction acts on the main shaft 4 during steady operation of the compressor. (1) The force due to the weight of the main shaft, motor rotor, balance weight, etc. (this force is F).

It is called and acts in a downward direction. ) (2) The discharge pressure acts on the upper end surface of the main shaft and the lower surface of the main shaft, causing the main shaft 41114 and the eccentric shaft portion 4 to
Since the pressure receiving area differs depending on the diameter of d, a thrust force acts on the main shaft. (This force is called t-F. Generally, the shaft diameter d1 of the main bearing portion of the main shaft 4 is the shaft diameter d of the eccentric shaft portion 4d.
Since it is greater than 1, this force acts in an upward direction. )
Next, (8) the magnetic thrust of the motor rotor acts on the main shaft. (This force is called 7F-, and the direction of this force acts either upwardly or downwardly depending on the assembly position of the electric rotor part 11Ja and stator part 10b.) Therefore, these forces The sum is the total force that acts primarily. When this force is expressed as Fu, it becomes the following formula. (The force directed upward is positive.) pu = Fs R±F.

Fu(When Q, the main axis tries to move downward, so
This force Fu is received by the thrust bearing portion 8 of the main bearing 8.

However, when F"> O, the main shaft moves upward and exhibits a phenomenon in which the main shaft floats. In this case, the upper end surface 4b of the eccentric shaft comes into contact with the bottom surface 3b of the orbiting scroll host part,
This part receives thrust force Put-. This pattern is shown in FIG. This is because the relationship II (this is called Css) between the upper end surface 4b of the eccentric shaft and the bottom surface 3b of the orbiting scroll boss is the balance between the tip surface 32 of the orbiting scroll boss and the upper part of the main bearing facing it. Upper end surface of weight part 4.1! If it is smaller than the dose line (this is called cb), that is, C5 (Cb occurs at 0. Conversely,
When C5>Cb, the upper end 114c of the balance weight portion comes into contact with the tip surface 3C of the boss portion. However, since the boss bottom surface 3b and the boss tip end surface 3C, which are the contact surfaces, do not have a bearing structure, wear due to sliding easily occurs, and friction loss increases in these parts, causing compressor damage. Input increases. As shown in FIG. 3, when the contact surface is the bottom surface 3b of the boss part, abrasion powder is generated at this part, and this abrasion powder mixes into the bearing gap 19 of the orbiting scroll boss part bearing 7. This may lead to galling or seizure of the bearing 7.

The present invention solves the problem that the sliding contact in the above-mentioned parts without the bearing structure increases the friction loss per meter and reduces the mechanical efficiency of the compressor, and also causes the generation of wear particles in that part. To solve the galling phenomenon (seizure accident). Furthermore, the purpose is to improve the reliability around the bearing.

In order to achieve the above-mentioned object, the present invention has a main shaft floating phenomenon in which the main shaft moves upward during operation. It is provided on the upper end surface of the balance weight section opposite to the tip end surface. That is, between the thrust bearing part of the orbiting scroll boss part and the thrust bearing part of the main bearing, there is provided a balance weight part that is engaged with and integrated with the main shaft,
The balance weight section is characterized in that the upper end surface and the lower end surface thereof have a structure of a thrust bearing surface.

An embodiment of the present invention will be explained based on FIGS. 4 to 6.
゜ Due to the thrust force Fu acting upward, the main shaft moves upward by 411J, and the upper end surface 4C of the balance weight part 4a located at the lower part of the eccentric shaft part 4d come into contact with. The orbiting scroll boss bearing 20 includes a journal bearing part 20f that receives a radial load, and a thrust bearing part 20b that receives a thrust load. The thrust bearing portion 20b has 7
U/Ji f! 1All I construction 01 This keeps the bearing surface pressure low. In addition, a plurality of oils 111120m extending in the radial direction are formed in the thrust bearing portion. This oil groove 20m is an oil drainage groove for releasing lubricating oil flowing between the bearings 1119 to the back pressure [14].

In addition, as shown in Figure 4, the upper end surface 4b of the 1st eccentric shaft part and l1
There is always a gap between the scroll boss S and the surface 3b, and the gap is indicated by C3l.

The main bearing 8 has a main shaft 4 medium electric #horizontal 10 as in the conventional technology.
Thrust bearing section 8 that supports the weight of the rotor section 1011, etc.
It has a. Between the thrust bearing part 20b of the m-times scroll boss part bearing 20 and the thrust bearing part 8a of the main bearing 8, there is provided a pass/suit part 4a that is engaged with and integrated with the main shaft 4, and the balance weight part The upper end surface 4C and the F end surface 4e of 4a serve as thrust bearing surfaces. Therefore, depending on the positive or negative direction of the thrust force Fu acting on the main shaft 4, the upper end surface 4c of the balance weight portion 4a or
Either one of the lower end surfaces 4C becomes a contact surface with the slide IIb. Regardless of the positive or negative direction K of the thrust force Fu acting on the main shaft 4, the upper end surface 4b of the eccentric shaft and the orbiting scroll boss part bottom surface 3b of the eccentric shaft VC1 are arranged so as not to come into sliding contact with each other. The relationship H (jh') between the thrust bearing surface 21 of the orbiting scroll boss bearing 20 and the upper end surface 4c of the balance weight section 4a on the upper part of the main bearing facing this
) to a small value. Therefore, the dimensions of each member are determined so that Cs/>Cb.

Next, other embodiments shown in FIGS. 1 to Jle will be described. The $7 figure is lll11g! Actual tII in which the lower end surface 2IC of the journal bearing section 21 that receives a radial load is used as a thrust bearing section as a scroll boss section bearing.
It is Af1. In this case, the lower end surface 21C is assembled so that the tip surface 3C of the boss portion 3a also protrudes downward to avoid contact between the tip surface 3C and the balance weight portion 4a41 of the main shaft 4. 8 and 9 show drain oil 11121 leaking to the lower end surface 21C of the journal bearing part 21.
Next, the other embodiment shown in Fig. 1110 and Fig. 11, which shows the shape of b, is an embodiment g4 in which a journal bearing part 22 and a thrust bearing part 23 are separated as bearings provided in the orbiting scroll boss part. . The thrust bearing section 23 is provided on the tip surface 3G of the m-times scroll boss section, and has a thin ring-shaped bearing structure. In addition, in this embodiment, the drain oil i$123b extending in the radial direction is provided in the drain oil i$123a.
Although the bearing part supporting the thrust force Fu is provided on the end face 3C of the orbiting scroll boss part 3a, the same effect can be obtained even if it is provided on the lower end face 4C of the balance weight part 4m opposed to the bearing part 3a. This embodiment is shown in FIG. In this case, the thrust surface 24& of the thrust bearing section 24 slides on the opposing boss section tip surface 3C.As explained above, according to this invention, the main shaft floats and supports this floating blade. By providing the thrust bearing section on the top four surfaces of the orbiting scroll boss section or on the upper end surface of the balance weight section opposing this, sliding contact in the thrust direction (
(including strong contact, etc.), and the generation of abrasion powder that can cause bearing troubles can be minimized. As a result of the above-mentioned effects, the friction II loss is reduced, the mechanical efficiency of the compressor is improved, and the reliability of the bearing layer 9 is improved.

[Brief explanation of the drawing]

Diagram 1 shows the overall structure of a conventional hermetic scroll compressor. The m sectional view, FIG. 2, and #I3 are detailed views of the conventional orbiting scroll boss portion bearing and are all longitudinal sectional views. Figures 514 to 86 show a complete example of the present invention Q,
@4wJ is a vertical sectional view around the orbiting scroll boss portion bearing, jlIs is a plan view showing the bearing structure of FIG. 4, and FIG. 6 is a ff-ff sectional view of FIG. 5. Figures 7 to Broom 9
The figures show other embodiments, FIG. 7 is a vertical cross-sectional view around the bearing of the orbiting scroll boss, FIG. 8 is a plan view showing the bearing structure of FIG. 7, and FIG. JllF9 is a vertical cross-section of the bearing structure of FIG. Show the diagram. Figures #I10 and #I11 show other examples, and the 10th
The figure is a vertical sectional view of the II 1st scroll boss bearing, 11th
The figure is a bottom view of the thrust bearing shown in Fig. 10, and Fig. 12E shows still another embodiment, which is a longitudinal sectional view around the orbiting scroll boss portion bearing. 2...Fixed scroll 3...Orbiting scroll 3
51...lIR rotation scroll boss WA 4...Main shaft 4d...Eccentric shaft 47...Orbiting scroll boss part bearing 8...Main bearing 23...Thrust bearing part 1
Figure 1 4m Saijikuni 蓼bcl Half IOm j11 out

Claims (1)

[Claims] 1. Scroll compression in which a fixed scroll member formed by two upright horns of an end plate K1m and an orbiting scroll member are engaged, and the orbiting scroll member is rotated relative to the fixed scroll member to compress gas. In the machine, a boss part that supports a bearing is provided on the back surface of the orbiting scroll member, and a journal bearing part that receives a radial load and a thrust bearing part that receives a thrust load are provided as the main bearing that supports the orbiting scroll boss part bearing and the main shaft. A scroll compressor featuring: 2. The orbiting scroll boss bearing and the thrust bearing of the main bearing are arranged on the lower end surface and the lower end surface of the balance weight that is integrally engaged with the main shaft, and the vertical upper end surface and the lower end surface form the thrust bearing surface. Scroll compressor according to claim 1. 1. The scroll compressor according to claim K1 or 2, wherein the orbiting scroll boss bearing is formed of a sliding bearing that integrates a journal bearing and a thrust bearing. 4. The scroll compressor according to any one of claims 1 to 3, wherein a thrust bearing surface is formed on the lower end surface of the journal bearing. 5. A claim in which the gap between the bottom surface of the orbiting scroll boss part and the top end surface of the eccentric shaft part is set larger than the gap between the thrust bearing surface of the m-times scroll boss part bearing and the top end surface of the balance weight. Scroll compressor according to any one of Items 1 to 3.