JPS58133491A - Scroll fluid machine - Google Patents

Abstract

PURPOSE:To lower the frictional loss of a scroll, by varying the height or the depth of wrap in accordance to the winding angle thus avoiding the contact between both scrolls. CONSTITUTION:The wrapping depth of a fixed scroll 101 is varied in accordance to the scroll wrap winding angle with reference to the design depth Hdes. In other word, the height of the scroll wrap at the central portion where the flexure is at the maximum is made lower than the design referertial level Hdes, to avoid the strong contact dut to the pressure deformation between the scroll wraps. Consequently the frictional loss is lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a scroll fluid machine used for an expander, a compressor, etc. A scroll compressor for an air conditioner will be explained with reference to FIG. 1 as an example. FIG. 1 shows the overall structure of a scroll compressor. The scroll compressor includes both a fixed scroll and an orbiting scroll 20, which are compression element parts, and an orbiting scroll 2.
It is formed from a member 3 (for example, an Oldham ring and an Oldham key) that prevents rotation of the motor, a main shaft 4, an electric motor 5, a frame 6, and the like. These components are housed inside the closed container 7. Figure 1 shows that the inside of the closed container 7 has a discharge pressure (
This is a high-pressure chamber type compressor that operates in an atmosphere of high pressure (high pressure side).

The operation diagram will be explained according to the flow of refrigerant gas.

The low-temperature, low-pressure refrigerant gas is guided from the suction pipe 8 and reaches the suction hole 15 in the fixed scroll. The refrigerant gas flowing into the compression element section is caused by the orbital movement of the orbiting scroll, which is prevented from rotating, into a closed space 10 formed by both scrolls.
, If gradually decreases and moves to the center of the scroll, the pressure of the refrigerant gas increases and it is discharged through the central discharge hole 16. The discharged high-temperature, high-pressure refrigerant gas fills the sealed volume iSI and is guided to the outside via the discharge pipe 9. Therefore, high discharge pressure (indicated by symbol pa) acts on the upper space 12 of the fixed scroll 1 and the space 14 of the electric motor rotation. On the other hand, in the space 13 surrounded by the lower part of the orbiting scroll 2 and the frame 6, gas pressure (this pressure is
(This force is a separation force that tries to push down the orbiting scroll 2. This gas force is expressed as F
Display as g. ), a pressure (indicated by the symbol pm) between the suction pressure (low pressure side pressure) and the discharge pressure acts. The orbiting scroll 2 is pressed against the fixed scroll 1 by the gas force at the intermediate pressure pm (this force is indicated by 7 m). The power relationship between the two is F m ) P
g.

Next, with reference to FIGS. 2 and 3, in the prior art, since gas force acts on the fixed scroll 1 and the orbiting scroll wrapper, as shown in FIGS. 2 and 3, In addition, both scrolls are deformed mainly in the axial direction due to pressure. FIG. 2 shows a modification of the fixed scroll 1. In FIG. The broken line shows the f-shape due to the pressure during operation, and the solid line shows the deformation when stationary (when the operation is stopped). As shown in Figure 2,
Since the high discharge pressure pi acts on the entire surface of the upper portion of the fixed scroll, the fixed scroll end plate portion 1a and the wrap portion 1b bend downward, and the center portion of the fixed scroll is deflected the most. The amount of deflection W depends on the rigidity of the entire fixed scroll, the rim, and the thickness TK of the scroll end plate 1+a.

FIG. 3 shows a modification of the work schedule 2.

The orbiting scroll 2 has an orbiting scroll end plate part 2's and a wrap part 2b based on the relationship between the gas force Pg due to the pressure p1 inside the scroll and the gas force 1m' at an intermediate pressure pm.
moves upward, and the center of the orbiting scroll flexes the most. As with fixed scroll 1, this amount of compensation is mainly
This largely depends on the thickness T2 of the scroll bond plate portion 2a.

However, the conventional example has a fixed scroll 1 and an orbiting scroll 2.
The lap depths and lap heights of the two are designed to be equal. Also, the scroll wrap winding angle (for example, if the scroll wrap curve is involute as shown in Figure 4, it corresponds to the involute extension angle. ).
They are all equal and have a uniform lap height or depth. Therefore, the following relationship exists.

Hdos': i (B) Scroll Wrap Height When both the fixed and orbiting scrolls are meshed in a deflected state and the compression action continues, the deflected portion of the scroll, especially 0 in FIG. part and the wrap tip part 1 of part 0 in Fig. 3.
Strong contact (hit) between C12C and the opposing tooth root surface 00
$? On the contrary, it accelerates the wear of both scrolls in that area. Moreover, when the contact between metals becomes strong, friction loss increases and compressor performance (performance equivalent to total adiabatic efficiency) decreases. Furthermore, if the lubrication at the tip IC12C is poor, the reliability of the compressor may be affected, such as seizing, steering failure, and even damage to the scroll wrap. I'm also worried.

In addition, in the case of a compressor with a structure in which the pressure on the back side of the fixed scroll or orbiting scroll is lower than the pressure in the compression chamber (for example, an open scroll compressor), the deformation shown in Figure 2.3 will occur in the opposite direction. If the wrap height H is a constant value, the gap will become large in the center, causing performance deterioration.

The present invention solves the above problem, namely, the deformation of the scroll member due to pressure, especially the axial deformation (bending) caused by K. The purpose of this invention is to solve the problem of low F1 in compressor performance and reliability concerns caused by strong contact between both scrolls or an increase in the gap between both scrolls.

In order to achieve the above object, the present invention takes into account the deformation of the scroll member due to pressure, determines the height of the scroll wrap, and eliminates strong contact between both scroll wraps mainly in the axial direction. That is, the height R of the scroll wrap is adjusted according to the wrap angle so that it becomes a function of the scroll wrap wrap angle formula,
Or, it is characterized by changing the lap depth.

An embodiment of the present invention will be explained based on FIGS. 5 to 9. FIG. 5 shows an example in which the wrap depth of the fixed scroll 101 is changed from the design reference depth lid's to the scroll wrap yellow angle 0, i.e.,
The scroll wrap tip 101C is made low in consideration of the amount of deformation (deflection) due to pressure, and the scroll wrap tip is tapered. The relationship between the scroll wrap height H and the scroll wrap winding angle formula can be expressed by the following formula.

On the other hand, FIG. 6 shows an embodiment of the present invention on the orbiting scroll 102 side. On the orbiting scroll side, in order to avoid strong contact with the center of the scroll, the center wrap tip 102C
is lowered to become Hdea)H. Therefore, the wrap height H of the orbiting scroll also has a wrap curve that satisfies the above equations (3) and (4).

For the embodiments shown in FIGS. 5 and 6 above, when the wrap depth or wrap height H is shown in relation to the scroll wrap winding angle formula, it is as shown in the following FIG. 7 or 8. Become. FIG. 7 shows a linearly varying pattern in which the height H of the scroll wrap of the scroll member has a constant slope m relative to the winding angle equation of the scroll wrap. In other words, the start of scroll winding at the center of the scroll (in = in θ
), the wrap height is the lowest, and the wrap height is the highest at the end of the scroll winding on the outer circumferential portion of the scroll (En=En e), and the height is set to the design standard value Hdθ8. Practically speaking, the difference between the maximum height and maximum depth of the scroll wrap and the minimum height and minimum depth of the scroll wrap is considered to be within a range of about 20KZL1, and therefore the slope m will be a small value. Figure 8 shows the relationship between ■ and on when the scroll wrap shape changes the wrap height stepwise. That is, the height of the scroll wrap is set at the center part where the amount of deflection is the largest, in other words, in the range where the scroll winding angle is small (in Fig. 8, this range is expressed as Entry S≦Entry≦Man m). It is set lower than the design reference value Hdea to avoid strong impact due to pressure deformation between the scroll wraps at that portion. Therefore, in the other parts except for the center of the scroll (in terms of the range of scroll winding angles, the height of the scroll wrap is 0, which is 0 where 0 is 0 when 0 is 0) There is.

Next, FIG. 9 shows a method of changing the depth of the fixed scroll wrap, with the bottom 101d of the fixed scroll wrap being moved to the reference depth H.
This is an example modified from des. Therefore, the depth reference plane is the scroll wrap tip 101'C.
It is. In the embodiment shown in FIG. 9, the same effects as in the embodiments shown in FIGS. 5 and 6 can be obtained. In addition, a scroll wrap in which the wrap height or wrap depth H changes in a multiple curve shape (for example, a quadratic curve or a cubic curve) with respect to the winding angle formula of the scroll wrap has a similar effect. can get.

As explained above, according to the present invention, it is possible to avoid strong contact between both scroll members due to deformation of the scroll member due to pressure. Therefore, friction loss is reduced and compressor performance is improved. Since the wear of the single scroll wrap itself can be reduced and the generation of abrasion powder can be suppressed as much as possible, the reliability of the press machine as a whole is improved.

Furthermore, since the wrap depth and wrap height are determined in consideration of the deformation caused by the pressure of the fixed scroll and the orbiting scroll, it is possible to reduce the thickness of the scroll end plate to some extent, which greatly affects the deformation. Therefore, it is possible to reduce the weight or size of both scrolls, thereby reducing the cost.

[Brief explanation of drawings]

FIG. 1 is an overall structural diagram of a scroll compressor, FIG. 2 is a vertical cross-sectional view of a conventional fixed scroll, FIG. 3 is a vertical cross-sectional view of a conventional orbiting scroll, and FIG. 4 is an explanatory diagram of an involute curve. 5 and 6 are vertical cross-sectional views of scroll members showing one embodiment of the present invention, with FIG. 5 showing a fixed scroll and FIG. 6 showing an orbiting scroll. 7 and 8 are diagrams showing the relationship between the scroll winding angle and the scroll wrap height, respectively. FIG. 9 is a longitudinal sectional view of a fixed scroll showing another embodiment. 101...Fixed scroll 102-...Orbiting scroll 101! L, to2a...Scroll end plate part 1
01 b, 1021)...Scroll wrap section 101
G, 102C...Scroll tip 02 耶7m Warm? ω 270JL/ Ra v'lp'i'hix Cod) 90 Procedural amendment (1 button 1982 Patent Application No. 14956 Title of invention Scroll Fluid machine correction person'51) (゛wo samurai 2I ['' Standing work
Where・Table h −TF, [Tl
Masaru Katsu Shigeyo Person 1, □ ・Self 100-100 Marunouchi-chome, Chiyoda-ku, Tokyo Kashikikai lR27 Seifl Office, JL
During the talk...435-4221 Supplement 11: Contents of the attached standard amendment content 1, "Thickness T of 1.8" in line 17g14 on page 4 of the specification was changed to "Thickness T of 1a" correct. 2. IF in lines 17 and 18 of the same page, , 'J is replaced with 'F
Correct it to "m". 3. Page 5, lines 13 to 16 are corrected as follows. H=H'=Const・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・(1) d... d where H: Fixed scroll wrap depth d... H4゜,': Orbiting scroll wrap height 4, 8th page 2
Correct the line as shown below. 71 Shizuku 0・・・・・・・・・・・・・・・・・・
・・・・・・・・・(4) eλ 5, line 6 of the same page “Hdes>HJ [Hd,, )
Correction to HJ. 6. On the same page, line 20, Or) (correct des J to "Hdl,". 7. On page 9, line 3, or 20Kmj, be corrected to r20#mJ. 8. On the same page, line 0 to line 11. , 16th line, 19th line [HdesJ rH, , J K correct f.

Claims (1)

[Claims] A fixed scroll member and an orbiting scroll member each having a spiral wrap upright on the neck and end plate are provided, and both scroll members are engaged with each other inside, and the orbiting scroll member is connected to the fixed scroll member. In a scroll fluid machine with an orbiting motion, the wrap height and/or depth is adjusted relative to the wrap angle of the scroll wrap such that the upright wrap height and/or depth is a function of the wrap angle of the scroll wrap. Scroll fluid machine characterized in that the wrap height and/or depth changes in a stepwise manner with respect to the winding angle of the scroll wrap. The fluid machine according to item 1. 3. The fluid machine according to claim 1, wherein the wrap height and/or depth changes in a multi-dimensional curved manner with respect to the winding angle of the scroll wrap.