JPH0772548B2 - Hermetic scroll compressor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor for air or refrigeration and air conditioning, which employs an oil injection mechanism or a refrigerant injection mechanism for cooling a working gas.

[Conventional technology]

As a device provided with a cooling mechanism for cooling the working gas of the scroll compressor and for cooling the compressor body, for example, Japanese Utility Model Publication Sho 56
As shown in Japanese Patent No. 85087, a so-called oil injection method is known in which high-pressure oil is injected through two oil injection holes provided in the end plate portion of the fixed scroll via an oil cooler.

[Problems to be Solved by the Invention]

The scroll compressor has a pair of compression chambers, and therefore, the oil injection hole and the pipe require two locations.
Therefore, there are two adjusting points for the oil supplied to the pair of compression working chambers, and there is a problem with a method of evenly distributing the oil to both compression chambers, and there is a problem that this oil amount adjusting method is difficult. It was That is, since there is only one pair of oil pipes, two throttling mechanisms are required for uniform and accurate flow rate adjustment.

Further, since the piping around the compressor is complicated and the oil injection hole is provided in the end plate portion along the side wall of the scroll wrap, high processing accuracy is required for positioning the pores, There was a problem that it would lead to higher costs.

An object of the present invention is to inject a liquid into two compression chambers of a scroll compressor to effectively cool a working gas in the compression chamber, and to simplify a liquid injection mechanism to provide a compact and inexpensive compressor unit. Another object of the present invention is to obtain a hermetic scroll compressor in which the flow rate of the injected liquid can be easily adjusted and the cooling action for the two compression chambers can be equalized.

[Means for Solving the Problems]

In order to achieve the above object, the present invention accommodates a scroll compressor and an electric motor in a closed container, and the scroll compressor wraps a fixed scroll and an orbiting scroll in which a spiral wrap is upright on a disk-shaped end plate. Are engaged with each other inside and the orbiting scroll is engaged with an eccentric mechanism that connects to the rotating shaft, and the orbiting scroll is orbitally moved with respect to the fixed scroll without rotating. A suction port that opens to the inside is provided, and gas is sucked in through the suction port, and is compressed around the compression chamber formed by both scrolls to reduce the volume and compress the gas. And discharges the compressed gas to the outside of the closed container through a discharge pipe, and injects a liquid into the compression chamber for cooling the working gas. In a hermetic scroll compressor provided with an inlet mechanism in the end plate portion of a fixed scroll, an injection mechanism for injecting the liquid includes a liquid injection hole formed in one place in the end plate portion of the fixed scroll and the closed container. A liquid injection pipe that penetrates through and is connected to the pores to supply the cooled liquid to the pores, the pores opening to face the wrap tooth tip surface of the orbiting scroll, and a fixed scroll wrap Of the compression chamber formed by the outside of the orbiting scroll wrap and the inside of the orbiting scroll wrap, and the compression chamber formed by the inside of the fixed scroll wrap and the outside of the orbiting scroll wrap. Is formed in the vicinity of the central portion between the wraps on the tooth bottom surface of the fixed scroll wrap.

[Action]

According to the present invention, the pores for injecting the cooled liquid (lubricant oil or liquid refrigerant) are swirled with the compression chamber formed by the outer side of the fixed scroll wrap and the inner side of the orbiting scroll wrap and the inner side of the fixed scroll wrap. Since it is formed near the central portion between the wraps of the tooth bottom of the fixed scroll wrap so as to intermittently communicate with the two compression chambers of the outside of the scroll wrap, the injection pores are fixed. By forming only one scroll, the cooling liquid can be intermittently and alternately injected into the two compression chambers, and the working gas can be effectively cooled.

Further, since only one pipe for liquid injection is required, the pipe structure around the compressor can be simplified and a compact compressor unit can be obtained.

The injection pore has a function of adjusting the flow rate of the injection liquid, but in the present invention, since only one pore needs to be provided,
Compared to the conventional technology that needed to have two pores,
It is easy to control the flow rate of the injected liquid, and the cooling action for the two compression chambers can be made uniform.

Further, since the liquid injection fine hole is provided near the central portion of the tooth groove of the fixed scroll, the processing accuracy in positioning the fine hole can be relaxed.

〔Example〕

FIG. 1 shows an embodiment of the present invention and shows a refrigerant compressor unit for refrigeration and air conditioning having an oil injection mechanism.

A vertical electric compressor having a scroll compression base 2 on the upper side and a motor unit 3 on the lower side is housed in the closed container 1. The compressor part is a fixed scroll 5 which constitutes a compression element.
And orbiting scrolls 6 (both wraps are shown reduced for modeling purposes), rotation preventing members 6a of the orbiting scrolls 6, and the orbiting scrolls 6
A rotary shaft 7 having a crank shaft 7a engaging with the rotary shaft 7, and a bearing portion supporting the rotary shaft 7, that is, a bearing 6c of the orbiting scroll 6.
And a main bearing 4a formed on the frame 4 and an auxiliary bearing 4b below the main bearing 4a. This hermetic scroll compressor is of a high pressure chamber type in which the hermetic container 1 is in an atmosphere of discharge pressure (high pressure side pressure) Pd. The shape of the scroll wrap is an involute or a curve similar to this.

Next, the operation of the scroll compressor will be described according to the flow of the refrigerant gas (the flow of lubricating oil inside the compressor will be omitted). The constant temperature and low pressure refrigerant gas is introduced from the suction pipe 11 as indicated by the solid line arrow, and the suction joint 12 and the check valve portion 13 are introduced.
The refrigerant gas that has reached the suction port 14 in the fixed scroll 5 and has reached the compression element portion is introduced into the hermetically sealed space. Due to the revolving movement of the orbiting scroll 6 which is prevented from rotating, the compression chamber 8 formed by both scroll members gradually shrinks and moves to the central portion of the scroll, and the pressure of the refrigerant gas is increased so that the refrigerant gas is discharged from the central discharge port 10. The discharged high-temperature high-pressure refrigerant gas is discharged into the upper space 1a in the closed container 1, and then the space 1b around the electric motor via the passages 16a and 16b.
Is discharged to the outside through the discharge pipe 18 at a high discharge pressure Pd. The oil injection pipe 21 is connected to the oil injection pores 22 provided in the end plate portion of the fixed scroll 5.

In the steady operation of the compressor, the oil supplied through the oil injection pipe 21 is injected into the compression chamber 8 through the pores 22 to cool the working gas in the compression chamber. The oil injected from the oil injection pipe 21 is injected into the compression chamber 8 through the pores 22, is mixed with the working gas, and is discharged from the discharge port 10 to the discharge chamber 1a together with the working gas. Next, it reaches the electric motor chamber 1b through the passages 16a and 16b, where the working gas and the oil are separated.
The separated oil falls and is stored in the lower part of the closed container 1.
The working gas with a small oil content reaches the external oil separator 23 through the discharge pipe 18. Here, the oil in the working gas is separated again, and the oil is supplied as oil for injection through the oil pipes 24, 25. Reference numeral 26 is an oil cooler, and 27 is an oil amount adjusting valve. An oil take-out pipe 28 is provided at the bottom of the container, the oil pipe 28 joins with the oil pipes 24, 25, and these oil pipes 28, 25, 21 and the like constitute an oil injection pipe path. . The solid arrows indicate the flow direction of the working gas (refrigerant gas), and the broken arrows indicate the oil flow direction. The gas from which oil has been separated by the oil separator 23 is sent to the condenser 30 through the pipe 29.

Next, the oil injection pores 22 will be described in detail below. FIG. 2 is a bottom view of the fixed scroll 5 showing the positions of the pores. In the figure, 5e and 5e 'are fixed scroll wraps.
5b shows the end of winding. Fixed scroll wrap tooth bottom
An oil injection fine hole 22 is provided in an end plate 5a at a substantially central position of 5g.

FIG. 3 to FIG. 5 show the operating state of the compression mechanism using the fixed scroll of the embodiment of FIG. 1 at the time of oil injection.

In the present embodiment, oil is intermittently injected into the two adjacent compression chambers 8a and 8b through the single oil injection pore 22. As described above, by intermittently connecting the compression chambers 8a, 8b and the oil injection pores 22 to each other, it is possible to have a function of limiting the amount of oil supply (a so-called throttle portion having a function of adjusting the amount of oil supply). it can. In this case, the hole diameter ds of the pores 22 is the wrap thickness t of the orbiting scroll.
On the other hand, the following equation may be practically satisfied.

ds ≦ t (1) In the case of FIG. 2, the oil-injection pores 22 are located at positions intermittently communicating with the working chambers during the suction stroke of both scrolls. This provides a function to prevent oil compression at startup. In FIG. 2, the pores 22 are working chambers during the suction stroke (for example, working chambers communicating with the suction chambers 5f of 5g and 5g ′ shown in FIG. 3).
By temporarily communicating with the above, a cooling effect of the working gas during the intake stroke is produced, and this also has the effect of improving the volumetric efficiency.

4 and 5 show that the oil-injection pores 22 are intermittently communicated with the compression chambers 8a and 8b as the orbiting scroll 6 orbits. It is a figure explaining that an oil injecting action can be performed (be sure to communicate once for one rotation of the rotating shaft). In addition, 21 is a pipe for oil injection.

FIG. 6 shows that the oil injection hole is located closer to the center (position where the pressure is higher) than the position of the oil injection hole 22 shown in FIG. 2, that is, closer to the discharge port 10. This is an example in which 22b is provided. The pores 22b do not communicate with the working chamber formed by both scrolls during the suction stroke, but always communicate with the compression chamber 8c (see FIG. 3) that forms a closed space. In this way, the reason for providing the oil injection pores 22 or 22b at the substantially central position of the tooth bottom surface of the fixed scroll wrap is that the oil supply amount is efficiently distributed to both compression chambers 8a and 8b. Is.

FIG. 7 shows that the oil injection pores 22c provided in the end plate portion 5a of the fixed scroll 5 are located slightly closer to the center of the lap tooth groove than the wrap thickness t from the tooth side surface 5m of the wrap portion of the fixed scroll. One compression hole 8a is formed by the outside of the wrap of the fixed scroll 5 and the inside of the wrap of the orbiting scroll 6, and the pore 22c is formed by the inside of the wrap of the fixed scroll 5 and the outside of the wrap of the orbiting scroll 6. Compression chamber 8b
The compression chambers on both sides of and are connected to 8a and 8b intermittently.

That is, the embodiment of FIGS. 2 to 7 is an embodiment of a structure in which the injection holes are intermittently injected into the two compression chambers 8a and 8b by one injection hole.

FIG. 8 shows an embodiment of a refrigeration system using a liquid refrigerant injection mechanism. Solid arrows indicate the flow direction of the refrigerant gas, and dashed arrows indicate the flow direction of the cooling refrigerant liquid. The pipes 61 and 62 are liquid injection pipes, and the pores 63 provided in the end plate portion 5a of the fixed scroll 5 are the liquid refrigerant injection pores of the present invention. 64 is a condenser,
Reference numeral 65 is an evaporator, 66 is a main expansion valve, and 67 is an auxiliary expansion valve. The liquid refrigerant is introduced through the liquid injection pipe 61, and the liquid refrigerant for cooling is constantly or intermittently injected into both the compression chambers 8a and 8b through the liquid refrigerant injection pores 63. The injected liquid refrigerant removes the heat of compression (cooling of the refrigerant gas) during the compression process and is also used for cooling the entire compressor such as the motor 8. Reference numeral 68 is a reverse support valve for preventing the reverse flow of the liquid refrigerant and the refrigerant gas from the compression chamber to the sub expansion valve 67. Since the structure of each part of the scroll compressor is the same as that of each of the above-mentioned embodiments, the description thereof will be omitted.

FIG. 9 is a bottom view of the fixed scroll of FIG. 8 and shows an embodiment in which the liquid refrigerant injection holes 63 are provided in the end plate portion 5 a of the fixed scroll 5. The liquid-refrigerant injecting pores 63 are located relatively close to the discharge port 10 provided in the central portion of the fixed scroll. Through the fine holes 63, the liquid refrigerant is intermittently injected into the compression chambers 8d and 8d '.

〔The invention's effect〕

As described above, according to the present invention, it is possible to inject the cooled liquid alternately into the two compression chambers of the scroll compressor by providing only one fine hole in the end plate of the fixed scroll for injecting the liquid. As a result, only one liquid injection pipe for supplying the liquid to the pores is required, so that the pipe structure around the compressor can be simplified and a compact and inexpensive compressor unit can be obtained. it can.

In addition, the flow rate of the injection liquid can be easily adjusted as compared with the conventional technique that requires the provision of two pores or the like, and the cooling effect for the two compression chambers can be equalized.

Further, since the liquid injecting pores are provided in the vicinity of the central portion of the tooth groove of the fixed scroll, the processing accuracy in positioning the pores can be relaxed, and the cost of the product can be further reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of a compressor unit of a refrigerating apparatus for refrigerating and air-conditioning system equipped with an oil injection mechanism showing an embodiment of the present invention, FIG. 2 is a bottom view of the fixed scroll of FIG. 1, and FIG. FIG. 4 is a plan view showing a state in which the fixed scroll shown in FIG. 2 meshes with the orbiting scroll, FIG. 4 is a vertical sectional view of an oil injection mechanism portion, and FIG. 5 is a vertical sectional view showing its operation. FIG. 6 shows another embodiment, a bottom view of a fixed scroll in which the positions of oil injection holes are different, and FIG. 7 shows still another embodiment, which is a plan view showing a state in which the fixed scroll meshes with the orbiting scroll. FIG. 8 is a block diagram of a refrigerating apparatus having a liquid refrigerant injection mechanism showing still another embodiment, and FIG. 9 is a plan view showing a state in which the fixed scroll shown in FIG. 8 meshes with an orbiting scroll. . 5: Fixed scroll, 5a: End plate, 5b: Wrap, 6
…… Orbiting scroll, 6a …… End plate, 6b …… Wrap, 7…
… Rotation axis, 7a …… Eccentric axis, 10 …… Discharge port, 8a, 8b, 8c ……
Compression chambers, 22,22b, 22c …… Oil injection holes, 31,41,51, ……
Oil injection hole, 63 ... Liquid injection hole.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshikatsu Tomita 390 Muramatsu, Shimizu, Shizuoka Prefecture, Hitachi, Ltd., Mechanical Research Laboratory (72) Inventor, Kazutaka Sudo, 390, Shimizu, Shizuoka, Muramatsu, Ltd., Mechanical Engineering Laboratory, Hitachi, Ltd. (56) References JP-A-57-173503 (JP, A) JP-A-55-1007093 (JP, A) Actually developed JP-A-56-85087 (JP, U)

Claims (3)

[Claims] 1. A scroll compressor and an electric motor are housed in an airtight container, and the scroll compressor comprises a fixed scroll and an orbiting scroll in which a spiral wrap is erected on a disk-shaped end plate with the wrap being inside each other. In addition, the orbiting scroll is engaged with an eccentric mechanism connected to the rotating shaft to cause the orbiting scroll to orbit with respect to the fixed scroll without rotating, and the fixed scroll has a discharge port opening at the center and an outer peripheral opening. A suction port is provided, gas is sucked from the suction port, the compression chamber formed by both scrolls is moved to compress the gas while reducing the volume, and the compressed gas is discharged from the discharge port into the closed container chamber, A scroll for injecting the compressed gas to the outside of the closed container through a discharge pipe, and a fixed scroll injection mechanism for injecting a liquid into the compression chamber for cooling the working gas. In the hermetic scroll compressor provided in the end plate part, the injecting mechanism for injecting the liquid includes a small hole for injecting liquid formed at one position in the end plate part of the fixed scroll and the small hole penetrating the closed container. And a pipe for injecting a liquid that supplies the cooled liquid to the pores, the pores opening to face the wrap tooth tip surface of the orbiting scroll, and the outside of the fixed scroll wrap and the orbiting scroll wrap. Of the fixed scroll wrap so that the pores are intermittently communicated with two compression chambers formed by the inner side of the compressed scroll and the inner side of the fixed scroll wrap and the outer side of the orbiting scroll wrap. A hermetic scroll compressor, characterized in that it is formed near the center between the laps on the bottom surface. 2. The liquid injected from the injection mechanism is a cooled lubricating oil.
The hermetic scroll compressor according to item. 3. The hermetic scroll compressor according to claim 1, wherein the liquid injected from the injection mechanism is a liquid refrigerant cooled by a condenser in a refrigerating apparatus.