JPH04175482A - Horizontal scroll compressor for helium - Google Patents

Abstract

PURPOSE:To prevent the occurrence of abnormal sound and the unstable behavior of a Oldam mechanism by interposing an elastic body member restricting the amount of the axial displacement of the Oldam mechanism between the back surface of the end plate of a turning scroll and an Oldam ring main body. CONSTITUTION:A compressor is equipped with an Oldam mechanism 10 composed of Oldam key sections 10c and 10b, and of a ring section 10a in a space between a frame 15 fixing a stationary scroll 1 and the end plate 5a of a turning scroll 5 wherein the turning scroll 5 is allowed to freely revolve only. And in a horizontal hermetic type scroll compressor where a crankshaft 19 driven by an electric motor 17 for driving the turning scroll 5, is set in the horizontal direction, an elastic body member 46 restricting the axial displacement of the Oldam mechanism 10 is interposed between the back surface of the end plate of the turning scroll 5 and an Oldam ring main body section 10a. This thereby eliminates the unstable behavior of the Oldam ring 10 in the axial direction, and this also avoid collision between the Oldam ring 10 and the turning scroll 5, thereby lowering noise.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the structure of a horizontal scroll compressor for helium used in a helium refrigeration system, and in particular to an optimized structure around an Oldham ring that is an anti-rotation member.

[Conventional technology]

Scroll compressors used in traditional helium applications are
As described in Japanese Unexamined Patent Publication No. 61-187584, an oil-supplied scroll compressor for compressing helium is known which has a scroll shape in which the number of scroll wraps is about 25.

On the other hand, as a known example of a scroll compressor with a horizontal structure for refrigeration and air conditioning applications, Japanese Patent Application Laid-Open No. 61-212689
There is a publication. .

[Problems to be Solved by the Invention] “The above-mentioned conventional technology is suitable for cryopump equipment in which the ultimate cooling temperature is in the region of 20°C, among refrigeration equipment that uses helium gas. Relatively low pressure ratio (medium pressure ratio) with an operating pressure of 2 to 4
This is the operating condition for the region. (Hereinafter, unless otherwise specified, the operating pressure ratio will be simply abbreviated as pressure ratio.) In scroll compressors for such low pressure ratio applications, in helium liquefaction applications where the operating conditions are high pressure ratios such as a pressure ratio of around 20. Not available. Next, when attempting to design a scroll wrap number suitable for high pressure ratio applications, if an involute curve is used as the scroll curve, the number of turns will be around eight. If the number of turns of this scroll wrap increases, the outer diameter of the compressor will become too large and the total weight of the compressor will increase significantly, making it impractical to apply. The number of turns of the scroll compressor for specific applications was set around the number of turns, and it was confirmed that there were no practical problems. However, due to the operating conditions specific to high pressure ratio applications and due to the unique structure of the horizontal structure, the Oldham mechanism (Oldham ring), which is the rotation prevention member of the orbiting scroll, is displaced in the axial direction, and as a result, the back surface of the orbiting scroll end plate A problem arises in that it comes into contact with other parts and produces abnormal noises. This phenomenon also correlates with the fact that the torque fluctuation of the compressed gas increases as the pressure ratio increases.

Therefore, it is necessary to reduce the noise of the compressor caused by the behavior of the Oldham ring. Furthermore, in the case of a scroll compressor for helium, an oil injection structure is used to cool the helium gas. In helium liquefaction applications where it is highly necessary to increase the cooling effect, an even larger amount of injection oil is required than the amount shown in the cited example. Thus, when a large amount of oil is injected into the compression chamber.

Oil moves into the back pressure chamber through the back pressure hole (see FIG. 7), and this oil has an adverse effect on the behavior of the Oldham mechanism (such as generating abnormal noise). Therefore, it is necessary to eliminate the influence of injection oil. In addition, in refrigeration and air conditioning applications, there has not yet been any disclosure of a horizontally structured scroll compressor in which the amount of axial movement of the Oldham ring is restricted.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a fixed scroll and an orbiting scroll that serve as compression element parts, and engages both scrolls with their lap parts inside to fix the fixed scroll. An Oldham mechanism consisting of an Oldham key part and a ring part is provided between the frame and the end plate of the orbiting scroll. In a horizontal type hermetic scroll compressor, which is divided into two chambers, has an oil reservoir below both chambers, and has a crankshaft whose axis is set horizontally, which is driven by an electric motor for driving an orbiting scroll. An elastic member for regulating the amount of axial displacement of the Oldham mechanism is interposed between the back surface of the end plate of the orbiting scroll and the Oldham ring main body.

- [Function] The compressors shown in the cited examples so far are of the vertical type, and the Oldham ring is located in the horizontal direction and is configured to be supported by the keyway pedestal part of the frame part. Also,
The orbiting scroll is placed on the upper fixed scroll side by gas pressure through an intermediate pressure hole. Therefore, the Oldham ring's own weight is always supported by the keyway pedestal, and it remains stable and always on the lower side even during operation, making unstable behavior less likely to occur.However, in the case of the horizontal type, The Oldham ring can be easily moved in the axial direction, and is not configured to restrict the Oldham ring in the axial direction, so the Oldham ring tends to behave unstable in the axial direction. With the configuration of the present invention, the axial position of the Oldham ring can be regulated even in a horizontal type scroll compressor, and since an appropriate clearance is provided between the upper end surface of the Oldham ring and the back surface of the rotating mirror plate, it is possible to control the position of the Oldham ring in the axial direction. No sound is generated and unstable behavior of the Oldham ring does not occur.

〔Example〕

Embodiments of the present invention are shown in FIGS. 1 to 14,
FIGS. 1 to 4 show embodiments showing a structure for regulating the amount of axial displacement in the Oldham mechanism.

The explanation will be made based on FIG. 1 and FIG. 14 which is an overall configuration diagram.

Fixed scroll l and orbiting scroll 5 serving as compression element portions
The Oldham key portion 1 is provided between the frame 15 for fixing the fixed scroll 1 and the end plate 5a of the orbiting scroll 5, in which both scrolls are engaged with each other with their lap portions inside.
0c, 10b and a ring portion 10a, the gas discharge chamber 32 and the motor chamber 33 are connected to the frame 1 toward the side end opposite to the side end of the closed container 31.
5 and an oil reservoir 34 below both chambers.
In a horizontal type hermetic scroll compressor in which the axis of a crankshaft 19 driven by an electric motor 17 for driving an orbiting scroll is set in the horizontal direction, elasticity that regulates the amount of axial displacement of the Oldham mechanism 10 is provided. Body member 46
is interposed between the back surface of the end plate of the orbiting scroll 5 and the Oldham ring main body portion 10a.

FIG. 2 shows an embodiment in which a leaf spring 47 is attached as the elastic member 46 to the back surface of the end plate of the orbiting scroll 5. As shown in FIG. Leaf spring 4
Examples of the specific installation of 7 are shown in FIGS. 3 and 4. The leaf spring 47 is integrated with the orbiting scroll 5 side by a bolt 47b. Further, the leaf spring '47 is installed on the rear surface of the end plate of the orbiting scroll facing the Oldham key groove 15n side on the frame side in order to lightly press the Oldham ring against the frame side. Please note that the tip of the leaf spring
The lift amount of the leaf spring part is a small size (for example, 0.1
~0.2■). The leaf spring 47 is made of an elastic body that is deformable enough to support the own gravity of the Oldham ring 10. Further, as shown in FIG. 4, a light force approximately equal to the force of own gravity is sufficient as the force Fa1 for pressing the lower side t. Further, as shown in No. 31iI, the plate spring portion 47a has a size equal to the turning diameter no (≧2
i + We, where E is the orbiting radius of the orbiting scroll,
W is the ring thickness, which is determined based on the ring thickness (see Fig. 5). The reason why the size of this leaf spring is made rectangular and relatively large as shown in the figure is to make it correspond to the horizontal movement locus of the Oldham ring.

FIG. 5 shows the shape of the Oldham ring. lOa is the main body of the Oldham ring, and 10b and 10c are the keys.

FIG. 6 is an explanatory diagram schematically showing the upper and lower positional relationships of the Oldham ring 1o. In order to obtain stable behavior of the Oldham's ring, the gap Lr between the end face of the Oldham's ring main body 10a on the orbiting side and the back surface of the orbiting scroll end plate 5a facing thereto is set to a small dimension so as to satisfy the following formula. That is, Ω. , ≦Dor δ, /H, , - (1) where, n, r: Gap between the back surface of the orbiting scroll end plate and the end surface of the orbiting side of the Oldham ring main body, r: Outer diameter of the Oldham ring δ1: Oldham key groove and Radial gap H@r: key width dimension of the Oldham key part Specifically, in order to regulate the amount of axial displacement of the Oldham mechanism 10, in practical terms, it is The ratio of the gap Lr between this and the rear surface of the orbiting scroll end plate facing this and the outer diameter of the Oldham ring, r, is (l e
r / , D a r "F 2 X , 10-" may be set around 2.

Seventh! Figures 1 to 9 show other embodiments.

The rear side of the end plate of the orbiting scroll 5 is provided with a sliding part 5u that comes into sliding contact with the upper end surface of the Oldham ring opposite to this on both sides of the key groove part 5y, and faces the end face of the rotating side of the main body of the Oldham ring except for the sliding part 5u. A counterbore portion 5w is provided on the rear side of the mirror plate 5a so that the mirror plate 5a does not come into contact with anything other than a portion. Note that the width of the counterbore portion 5w may be set to a width dimension (for example, the same dimension as 40 dimension) that matches the movement locus of the Oldham ring in the horizontal direction (here, meaning the link direction). As shown in FIG. 7, the end plate 5a of the orbiting scroll is provided with pores 29a and 29b, so that the pressure in the back pressure chamber 36 existing on the back side of the end plate of the orbiting scroll 5 is equal to the suction pressure. The pressure is intermediate between the discharge pressure and the pressure that presses the orbiting scroll toward the fixed scroll.

10th (I) and 11 are examples showing the fixed scroll 1 and the oil injection structure for cooling helium gas.Helium gas and the entire compressor (mainly the electric motor 17)
A compression chamber 1 formed by both scroll parts is used to cool the
An oil injection pipe 40 is provided so that oil can be injected into the fixed scroll 1, and a hole 1w connecting the pipe 40 and the compression chamber 1-3 side is provided in the end plate portion of the fixed scroll 1. The diameter d6 of this oil injection hole 1w is larger than the lap thickness 7, and the oil injection hole 1w is formed in one place at the center of the tooth space. This structure of the injection hole has the effect of ensuring a large amount of cooling oil and suppressing pressure pulsations within the injection pipe 40.

FIG. 12 is a plan view of the frame 15, and FIG. 13 is a cross-sectional view. The reason why the radial grooves 15c are provided circumferentially on the frame pedestal surface 15b is to drain the oil accumulated in the side space of the end plate 5a' of the orbiting scroll to the sliding part of the Oldham mechanism part (
15n, 15y) and the sliding parts of the elastic members 46 and 47. 'When the oil spreads over the sliding part of the leaf spring part 47, the lubrication performance of that part improves,
Increases the smoothness of the Oldham ring movement.

FIG. 14 is a cross-sectional view showing the overall structure of a helium horizontal scroll compressor incorporating a leaf spring member 47 that regulates the behavior of the Oldham mechanism section 10.

As shown in FIG. 14, this scroll compressor is a hermetic, oil-filled scroll compressor, and has a hermetic container 3.
1, a discharge chamber 32 formed inside this, a motor chamber 33, and a lower oil reservoir 34a.

34b, a frame 15, a compressor section consisting of fixed and orbiting scrolls 1 and 5, a gas suction pipe 11, a back pressure chamber 36, and a compressed gas discharge pipe 16.

An electric motor 17, a rotational drive shaft (crankshaft) 19, an eccentric shaft (crank pin) 20, and an oil suction pipe 2 in the center
It has 3. A communication path 26a that guides helium gas and oil from the discharge chamber 32 to the motor chamber 33.

26b, and oil reservoirs 34a in both chambers 32 and 33.

Oil equalizing passages 27 for adjusting the level of the oil level of the fixed scroll end plate 1a are provided at the upper and lower portions of the outer circumferential portion of the fixed scroll end plate 1a, respectively. The frame 15 is a body 31a of the airtight container 31.
It is fixed inside with a bolt 15a.

The scroll compressor section includes a fixed scroll 1.

It is composed of an orbiting scroll 5 and an Oldham joint 10. As shown in FIG. 10, the fixed scroll 1 is composed of a disc-shaped end plate 1a and a wrap 1b formed by an involute curve or a curve approximated thereto and attached perpendicularly to the end plate 1a. ing. Further, the fixed scroll 1 is fixed to the frame 15 with a plurality of bolts 9 installed at intervals in the circumferential direction.

Each bolt 9 has bolt through holes 9a formed in the outer edge of the end plate 1a of the fixed scroll 1 at intervals in the circumferential direction.
(see FIG. 10), and is screwed into a screw hole provided in the outer edge of the frame 15 in alignment with the bolt through hole 9a. On the other hand, orbiting scroll 5
is a disc-shaped end plate 5a and a wrap l of the fixed scroll 1.
a wrap 5b formed in a shape that engages with the end plate 5a and attached perpendicularly to the end plate 5a;
The mounting is performed using a boss 5c provided on the opposite surface. An eccentric shaft 20 of a crankshaft 19 driven by an electric motor 17 is fitted with a bearing in a boss 5c.
When the crankshaft 19 is rotated by the electric motor 17, the orbiting scroll 5 is prevented from rotating via an Oldham joint 10 consisting of an Oldham ring and an Oldham key, so that the orbiting scroll 5 can rotate.

The helium gas suction pipe 11 is as shown in FIG.
Gas is introduced from outside the machine into the suction chamber 22 at the inner circumference of the fixed scroll of the scroll compressor.

Furthermore, as shown in FIG.
The side cover 31c on the third side has an oil extraction pipe 6 curved downward to take out oil from the oil reservoir 34 at the lower part of the chamber 33.
7a is connected to an oil pipe 51 outside the machine via an oil outlet 67, and this oil pipe 51 is connected to the compressor section side of the closed container 31 via an oil cooler not shown in FIG. It is connected to an oil injection pipe 40 passing through the side cover 31b. The oil injection pipe 40 is connected to an oil injection hole 1w provided in the end plate 1a of the fixed scroll 1. Note that 57 is a protective cover for a power supply terminal to the electric motor.

The closed space (compression chamber) 13 formed between the laps of the fixed scroll 1 and the orbiting scroll 5 decreases in volume as the orbiting scroll rotates, and therefore the gas (helium) taken into the compression chamber 13 from the suction chamber 22 is The discharge chamber 32 is compressed and discharged from the discharge port 2 at the center of the fixed scroll end plate 1a.
During this process, the gas is cooled by oil injected from the oil injection pipe.

A portion of the injected oil reaches the back pressure chamber via the back pressure hole. In conventional machines, this injection oil promoted the axial displacement of the Oldham ring, but according to the present invention, even if a large amount of oil is injected, there is no adverse effect on the behavior of the Oldham ring caused by the injection oil. It disappears. Although the present invention has been mainly explained with reference to a horizontal scroll compressor for use with helium, the present invention can also be applied to a horizontal scroll compressor for use in refrigeration and air conditioning using fluorocarbon gas.
It has similar actions and effects.

〔Effect of the invention〕

According to the present invention, (1) Collision between the Oldham ring and the orbiting scroll is avoided, which improves the reliability of both members and is effective in reducing noise during operation.

(2) Since it is possible to prevent the generation of abnormal noises caused by the injection oil and the Oldham ring, a larger amount of injection oil can be injected for cooling the compressor than in conventional machines. Therefore, this oil has a cooling effect and an effect of improving performance.

[Brief explanation of drawings]

Figures 1 and 2 are partial cross-sections of the right side of a horizontal scroll compressor according to different embodiments of the present invention. Figure 3 is a front view of a leaf spring member attached to an orbiting scroll, and Figure 4 is a plate Partial cross-sectional view around the spring member, (a) and (b) in Fig. 5
6 is an explanatory diagram simulating the vertical positional relationship of the Oldham ring 10, FIG. 7 is a plan view of the orbiting scroll, and FIG. 8 is a rear view of the scroll. FIG. 9 is a partial cross-sectional view of the end plate outer peripheral portion 5a,
Fig. 10 is a plan view of the fixed scroll, the first drawing is a partial sectional view showing the oil injection structure, Fig. 12 is a plan view of the frame, Fig. 13 is a cross-sectional view, and Fig. 14 is the behavior of the Oldham mechanism. 1 is a cross-sectional view of the overall structure of a helium horizontal scroll compressor incorporating a leaf spring member for regulating the helium. DESCRIPTION OF SYMBOLS 1... Fixed scroll, 1w... Oil injection hole, 5... Orbiting scroll, 10... Oldham mechanism part, 15... Frame, 32... Discharge chamber, 36...
...Back pressure chamber. 40...Oil injector pipe, 46, 47...Elastic body member, 51...Oil piping.

Claims (1)

[Claims] 1. A fixed scroll and an orbiting scroll are provided as compression element sections, and the scrolls are engaged with each other with their lap portions inside, and an Oldham key section and a ring section are provided between a frame for fixing the fixed scroll and an end plate of the orbiting scroll. A gas discharge chamber and a motor chamber are separated by a frame toward the opposite side end of the sealed container, and an oil reservoir is provided below both chambers, and an oil sump is provided below both chambers. In a horizontal hermetic scroll compressor in which the axis of a crankshaft driven by the electric motor for driving a scroll is set horizontally, the elastic member regulating the axial displacement amount of the Oldham mechanism is rotated. A horizontal scroll compressor for helium, characterized in that it is interposed between the back of the end plate of the scroll and the main body of the Oldham ring.