JPH0114436B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an oil-fed scroll fluid machine used as a refrigerant compressor or an air compressor for refrigeration and air conditioning, refrigerators, etc.

[Conventional technology]

Taking a refrigerating and air conditioning compressor as an example of an oil-supplied scroll fluid machine, its basic structure, lubrication system, etc. will be explained with reference to FIGS. 1 to 4. For ease of explanation, in each figure, the flow direction of working gas is shown by a solid line arrow, and the flow direction of lubricating oil is shown by a broken line arrow.

FIG. 1 shows the overall structure of a conventional hermetic scroll compressor for air conditioners. The compressor consists of two scroll members, a fixed scroll 1 and an orbiting scroll 2, which are compression element parts, an Oldham mechanism 3 and a main shaft 6 that prevent rotation of the orbiting scroll 2, and three bearing parts that support the rotation. Bearing 12 and main bearing 11
and auxiliary bearing 10, electric motor 9, fixed scroll 1
It is composed of a stationary member 4 (hereinafter referred to as a "frame") that fixes the frame. These components are
It is housed inside a closed container 23. FIG. 1 shows an example of the structure of a high-pressure chamber type in which the inside of the closed container 23 is in an atmosphere of discharge pressure (high-pressure side pressure).

The operation of the compressor will be explained according to the flow of refrigerant gas and the flow of lubricating oil.

The low-temperature, low-pressure refrigerant gas is guided from the suction pipe 19 and reaches the suction chamber 1f in the fixed scroll 1. As shown in FIG. 2, the refrigerant gas that has reached the compression element moves into the closed spaces 5a, 5 formed by both scrolls due to the orbital movement of the orbiting scroll, which is prevented from rotating.
As the refrigerant gas gradually shrinks and moves to the center of the scroll, the pressure of the refrigerant gas increases and it is discharged from the central discharge hole 1d. The discharged high-temperature, high-pressure refrigerant gas passes through the upper space 16 in the closed container 23 and the passages 13 and 14 to the motor room 1 around the motor.
7 and is led to the outside via the discharge pipe 20. (This high discharge pressure is indicated by the symbol Pd.) On the other hand, a space 18 surrounded by the back surface of the orbiting scroll 2 and the frame 4 (this is referred to as a "back pressure chamber")
To counter the gas force in the thrust direction due to the gas pressure in the plurality of sealed spaces formed by both the orbiting and fixed scrolls (this force becomes a separation force that tries to push the orbiting scroll 2 downward). Therefore, a pressure (indicated by the symbol Pm) between the suction pressure (low pressure side pressure) and the discharge pressure acts. The setting of this intermediate pressure is based on the fine holes 2 in the end plate 2a of the orbiting scroll 2.
c and 2d are provided, and the gas inside the scroll is introduced into the back pressure chamber through these pores, and gas force is applied to the back surface of the orbiting scroll. The method of applying this intermediate pressure is disclosed in JP-A-53-119412 and JP-A-55-37520, so a detailed explanation will be omitted.

Next, the detailed structure of the Oldham mechanism 3 is shown in FIGS. 3 and 4. An example of the Oldham mechanism 3 that is constructed from an Oldham ring 30 and Oldham keys 31 and 32 is illustrated. This Oldham ring 3
0 is sandwiched between the orbiting scroll 2 and the frame 4 (strictly speaking, the key pedestal 4a of the frame part),
Oldham keys 31a, 31 provided respectively
b, 32a, and 32b to prevent the orbiting scroll 2 from rotating. 37a and 37b are key grooves for attaching Oldham keys. Therefore, the Oldham ring is sliding at four locations 33, 34, 35, and 36.

With reference to FIGS. 5 to 7, the orbiting scroll 2
The structure around the outer peripheral portion 2f of the end plate will be explained. The head plate thickness of the head plate portion 2a of the orbiting scroll 2 has a uniform thickness regardless of the head plate outer peripheral portion 2f and the head plate central portion 2j (in FIG. 6, this head plate thickness is indicated by the dimension Hs). Further, the outer peripheral portion 2f of the end plate of the orbiting scroll 2 is sandwiched between the outer peripheral portion 1c of the end plate of the fixed scroll 1 and the pedestal 4b of the frame 4 with a small gap being maintained. In the case of FIG. 6, the minute gap is expressed as (Hf-Hs). (Here, Hf: the dimension between the frame top surface 4c and the surface of the pedestal 4b) A radial oil supply path 40 is provided in the end plate portion 2a of the orbiting scroll 2.
(for example, 40a, 40b, etc.) and oil supply holes 41 (for example, 41a, 41b, etc.) are provided.These oil supply holes 41 are engaged with oil grooves 42 provided in the end plate portion 1a of the fixed scroll 1.The orbiting scroll The end plate outer peripheral part 2f of No. 2 performs a turning movement between the end plate outer peripheral part 1c of the fixed scroll 1 and the pedestal 4b of the frame 4 around the frame center point (or the fixed scroll center point) Of. The positional relationship between the orbiting scroll 2 and the orbiting scroll 2 is as shown in Fig. 5. Fig. 7 shows a cross-sectional view of the frame 4. The frame 4 has a key pedestal 4a with a key groove 4f for attaching the Oldham key. 4e is a bolt hole for attaching the fixed scroll 1. In this way, the orbiting scroll 2
In addition to the back pressure chamber 18 at the back of the orbiting scroll, a space 43 is formed around the outer peripheral part 2f of the end plate, by the outer peripheral part 2f of the end plate, the outer peripheral part 1c of the fixed scroll opposing the end plate, and the frame 4. . Hereinafter, this space 43 will be referred to as a "frame chamber."

Next, the flow of lubricating oil will be explained using FIG. 1, FIG. 5, and FIG. 6.

The lubricating oil 7 is stored in the lower part of the closed container 23.
The lower end of the main shaft 6 is immersed in the oil at the bottom of the container, and the upper part of the main shaft is provided with an eccentric shaft portion 6a. is engaged with. The main shaft 6 has an eccentric vertical hole 6b formed from the lower end of the main shaft to the upper end surface of the main shaft for supplying oil to each bearing section.

At the lower part of the eccentric shaft part 6a, a balance weight 8 is formed so as to be engaged with and integrated with the main shaft 6 at the upper part of the main bearing, which faces the tip end surface of the orbiting scroll boss part 2e. The lower end of the main shaft 6 immersed in the lubricating oil 7 is in an atmosphere of high discharge pressure Pd, while the area around the downstream swing bearing 12 is in an atmosphere of intermediate pressure Pm, so there is a pressure difference of (Pd - Pm). According to
The lubricating oil 7 at the bottom of the container rises inside the eccentric vertical hole 6b. Also, due to the rotation of the main shaft 6, the eccentric vertical hole 6b
Centrifugal force acts on the oil inside, 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. Lubricating oil 7 rising inside the eccentric vertical hole 6b
The upper space 25 of the eccentric shaft portion 6a (the gap between the bottom surface of the boss portion of the orbiting scroll boss portion 2e and the upper end surface of the eccentric shaft portion 6a; It becomes a hydraulic room.
Hereinafter, it will be referred to as the "hydraulic chamber" 25. ). The lubricating oil in the hydraulic chamber 25 has a pressure approximately equal to the discharge pressure Pd, and as shown in FIGS. 5 and 6, a radial oil supply passage 40 provided in the end plate 2a of the orbiting scroll 2
The oil flows through the oil supply hole 41 to an oil groove 42 provided in the outer peripheral portion 1c of the end plate of the fixed scroll. The lubricating oil that has reached the oil groove 42 reaches the frame chamber 43 or the suction chamber 1f inside the scroll. Furthermore, the lubricating oil that has reached the swing bearing 12 and the main bearing 11 is drained into the back pressure chamber 18 through the respective bearing gaps. The lubricating oil that has reached the back pressure chamber 18 is transferred to the Oldham ring 30.
After lubricating the parts, it is injected into the working chamber formed by both scrolls 1 and 2 through the pores 2c and 2d, and then inside the scroll lap.
mixed with the refrigerant gas. Next, the lubricating oil is pressurized together with the refrigerant gas, and passes through the discharge hole 1d, the upper space 16, and the passages 13 and 14 to the motor chamber 17.
together with the refrigerant gas. The lubricating oil that has reached the motor chamber 17 has a large flow rate due to the large space, and falls to the bottom of the container due to its own weight. That is, the refrigerant gas and lubricating oil are separated in the motor room 17. The fallen lubricating oil is collected again at the bottom of the container and used to lubricate each part.

[Problem to be solved by the invention]

Next, problems of the prior art will be explained using FIGS. 5 to 8. A frame chamber 43 is formed in the outer peripheral portion 2f of the end plate of the orbiting scroll 2, and lubricating oil leaks into the frame chamber from the oil groove 42 or the back pressure chamber 18. The outer peripheral part 2f of the end plate of the orbiting scroll 2 has a minute gap (for example, between the outer peripheral part 1c of the end plate of the fixed scroll 1 and the frame 4
Since the frame chamber 43 is sandwiched by a gap of about 100 μm, the frame chamber 43 forms a kind of closed space. Therefore, the lubricating oil that once enters the frame chamber 43 stagnates within the space, and the frame chamber is finally filled with lubricating oil. In this state, when the orbiting scroll 2 continues to orbit inside the frame 4, the orbiting scroll 2 acts as a hydraulic pump, and the orbiting scroll 2 around the outer circumference of the orbiting scroll end plate acts as a hydraulic pump.
The changed oil pressure acts on g, resulting in an increase in the power required to drive the orbiting scroll. FIG. 8 shows the distribution of hydraulic pressure acting around the outer circumference 2g of the end plate of the orbiting scroll 2. Pf in the figure represents the varying oil pressure, while F ₀ is the resultant force of the oil pressure induced by the oil pressure distribution Pf, and Θ ₀ represents the direction of the force. Using FIG. 8, the amount of increase in required torque due to the action of the hydraulic pump of the orbiting scroll is given by the following equation.

F ₀ = D _SO /2・H _s・∫ ² 〓 ₀ Pf・sinOdθ …(1) T ₀ =ε・F ₀ …(2) Here, D _SO : Orbiting scroll end plate outer diameter (m) H _s : Thickness of the end plate of the orbiting scroll (m) F ₀ : Load due to hydraulic pressure Pf (Kg) ε : Radius of revolution (m) O ₀ : Direction of force of F ₀ (degrees) T ₀ : Increased torque (Kg・m) If the torque increases in addition to the gas compression torque and the friction torque of the bearing, Oldham ring, etc., there is a problem that the performance of the compressor, especially the total adiabatic efficiency, decreases. Furthermore, since the Oldham ring 30 is lubricated in a state similar to spray lubrication in the back pressure chamber, it is possible that the amount of oil supplied to the Oldham ring 30 is insufficient. If the amount of oil supplied to this part is insufficient, the friction torque will increase due to poor lubrication in the sliding parts 33 to 36 of the Oldham ring part, and wear on the sliding surfaces will be accelerated, resulting in a decrease in the performance and reliability of the compressor. The problem is that it encourages

As described above, in the prior art, oil enters the frame chamber 43 from the oil groove 42 on the fixed scroll side or the back pressure chamber 18, and the frame chamber 43 is filled with oil, resulting in an increase in power. It was hot.

The present invention was invented in view of the above-mentioned problems, and is aimed at suppressing the increase in power induced by the fluctuating hydraulic pressure distribution in the outer peripheral space of the end plate of an orbiting scroll, and further improving the lubrication of the Oldham mechanism. The purpose is to provide a highly reliable scroll fluid machine.

[Means to solve the problem]

In order to achieve the above object, the present invention communicates a frame chamber and a back pressure chamber on the outer periphery of the end plate of an orbiting scroll through an oil supply passage provided on the frame pedestal or on the outer periphery of the end plate of the orbiting scroll, and connects the oil supply passage to the Oldham It is provided towards the sliding part of the mechanism.

[Effect]

The oil accumulated in the frame chamber can easily move to the back pressure chamber side through the oil supply passage provided in the frame pedestal, etc., and the frame chamber is not filled with oil, and the oil pressure distribution Pf described above is prevented. The force F ₀ due to is significantly reduced. In equation (1) above, Pf
When is a constant value, it means that the value of F ₀ is zero, and in the present invention, the fluctuating hydraulic pressure distribution Pf of the prior art is made to have a uniform pressure Pf. be. In addition, since the oil supply passage is set toward the sliding part of the Oldham mechanism, the oil accumulated in the frame chamber can be directly supplied to the sliding part of the Oldham mechanism, ensuring lubrication of this part. It will be done.

[Embodiments of the invention]

Examples of the present invention will be shown below from FIG. 9 to FIG. 23. Figures 9 and 10 show a frame chamber 43 which is a side space of the outer peripheral part of the end plate of the orbiting scroll.
Oil supply holes 50 to 53 are provided in the frame to communicate the back pressure chamber 18, which is a space at the back of the orbiting scroll, and forcibly supply lubricating oil in the frame chamber 43 to each sliding part 33 to 36 of the Oldham ring part. This is an embodiment provided on a pedestal 4b. That is, two oil supply holes 50 and 52 are provided at positions that engage with the frame key pedestal 4a, and two oil supply holes are provided at positions that are angularly shifted by about 90 degrees.
Locations 51 and 53 are provided, respectively. That is, these oil supply holes 50 to 53 are connected to the frame chamber 43 and the back pressure chamber 18.
The oil supply hole is provided at a position where it engages with the sliding parts 33 to 36 of the Oldham ring part, which is a rotation preventing member. In Figure 10,
A pattern in which the lubricating oil in the frame chamber 43 moves through the oil supply hole 50 to the sliding part 35 of the Oldham ring parts 30 and 31 in the back pressure chamber 18 is shown by a broken line arrow.

11 and 12 show an embodiment of the present invention in which four inclined oil supply grooves 60 to 63 are provided in the frame pedestal 4b instead of the oil supply holes shown in FIGS. 9 and 10. . In this way, frame chamber 4
3 and the back pressure chamber 18 are shaped like oil supply holes 50.
〜53, or the oil supply groove 60〜
It may be 63.

13 to 18 show an embodiment in which an oil supply hole or oil supply groove is provided in the outer circumferential portion 2f of the end plate of the orbiting scroll 2 as a method of communicating the frame chamber 43 and the back pressure chamber 18. Figures 13 to 15 are
Oil supply holes 55 to 58 are provided on the outer periphery of the end plate of the orbiting scroll.
An example will be shown in which the following is provided. Note that the oil supply hole 56,
57 opens into an Oldham key groove portion 37a that engages with the sliding portion 33 of the Oldham ring portions 30, 32a in the frame chamber 43 and the back pressure chamber 18. 15th
The figure shows an example of the structure of oil supply holes 55 and 57 that communicate the frame chamber 43 and the back pressure chamber 18. The oil supply hole 5
5 and 57 are provided at positions that engage with the sliding portions 34 of the Oldham ring portions 30 and 31a, so that they have the shape of oil supply holes having bent paths. In addition, as shown in FIG. 13, the end plate outer peripheral portion 1c of the fixed scroll 1
A plurality of radial oil supply passages 70 are provided in the end plate 2a of the orbiting scroll 2 that supply oil to the oil groove 42 provided in the oil groove 42 (in the case of FIG.
70d), these oil supply passages 70 are provided in a direction shifted at a certain angle from the direction of the oil supply holes 55 to 58 provided in the outer peripheral portion 2f of the end plate of the orbiting scroll 2. In this way, the installation direction of the plurality of oil supply holes 55 to 58 and the radial oil supply passages 70 (70a to 70
This is an embodiment in which the installation direction d) is shifted by an angle of θ ₁ in FIG. FIG. 16 shows the structure around the outer periphery of the end plate when the cross section is taken along the line - in FIG. 13. 17 and 18 show four oil supply grooves 80 (80a to 80d) in place of the oil supply holes 55 to 58 provided on the outer peripheral part 2f of the end plate of the orbiting scroll 2.
This is another embodiment of the present invention in which the present invention is provided.

FIG. 19 shows another embodiment of the present invention in which an integral Oldham ring 91 (details not shown) in which the Oldham keys 31 and 32 and the Oldham ring 30 are integrated is used as the Oldham ring portion. In this case, the sliding portion of the Oldham ring portion is the Oldham key groove portion 37a, 90 of the orbiting scroll.
(Similarly on the frame side, the key groove part becomes the sliding part,
(Details not shown). In the case of FIG. 19, an oil supply groove 80 is provided on the orbiting scroll side and an oil supply hole 50 is also provided on the frame 4 side in order to supply oil to the sliding parts 90, 37a. Since two oil supply passages 80, 50 are formed for one sliding portion, the amount of oil supplied to the Oldham ring 91 is further increased. The embodiments shown in FIGS. 20 to 23 are cases in which the keyway (37a, 37b or 4f) of the Oldham ring portion is provided so that the frame chamber 43 and the back pressure chamber 18 communicate with each other. Therefore, the keyway 10
0,101 is from the key pedestal 4a to the frame pedestal 4
It is expanded to b. The keyway has an oil sump effect. 20 and 21 show an embodiment in which key grooves 101 and 102 are provided in the key pedestal 4a of the frame 4 to communicate the frame chamber 43 and the back pressure chamber 18. 22 and 23 show the orbiting scroll 2
The side keyways 103 and 104 are connected to the spaces 43 and 1.
This is an embodiment in which it is expanded and provided so as to communicate with 8.

With the above configuration, even if lubricating oil leaks into the frame chamber 43 around the end plate outer peripheral part 2f of the orbiting scroll 2, the oil supply holes 50 to 53, the oil supply grooves 60 to 63
The lubricating oil in the frame chamber 43 is transferred to the back pressure chamber 18 by
can be easily moved to. Therefore, according to the embodiment of the present invention, the lubricating oil does not stagnate in the frame chamber 43, so the oil pressure distribution with large fluctuations does not occur around the outer circumference 2f of the end plate of the orbiting scroll 2, which was seen in the prior art. . In this way,
The increase in power induced by oil pressure fluctuations as shown in equations (1) and (2) is completely eliminated, reducing the required power and improving machine performance compared to conventional scroll fluid machines. . Moreover, as explained in the problem of the prior art, the hydraulic pump action of the orbiting scroll is used inversely to allow the oil supply hole 5 to flow from the frame chamber 43.
0 to 53 or the sliding portion 35 of the Oldham ring portion 30 in the back pressure chamber 18 via the oil supply grooves 60 to 63, etc.
lubricating oil can be forcibly supplied to the Therefore, it is possible to increase the amount of oil supplied to each sliding part of the Oldham ring, which improves lubrication in the Oldham ring, which in turn reduces frictional torque in that part and suppresses wear on the sliding surfaces. can.

Further, as shown in FIG. 13 or FIG. 17, when oil supply holes 55 to 58 or oil supply grooves 80 are provided in the end plate outer peripheral portion 2f of the orbiting scroll 2, the installation direction of the oil supply holes and oil supply grooves, and the By shifting the installation direction of the radial oil supply passage 70 by a certain angle, the dimensions of the oil supply hole or groove and the radial oil supply passage can be set as desired. (For example, the dimensions such as the hole diameter of the oil supply holes 55 to 58 or the groove depth of the oil supply groove 80 can be set within the range of the end plate thickness of the orbiting scroll.) Thereby, the oil supply holes, the oil supply groove, or This facilitates the design (structural design) of radial oil supply passages.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to suppress an increase in power due to oil pressure fluctuations around the outer peripheral portion of the end plate of the orbiting scroll, and it is also possible to improve the lubrication of the Oldham ring portion. As described above, due to the synergistic effect of the two, it is possible to provide a scroll fluid machine with higher performance and reliability than the conventional machine.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of a conventional hermetic scroll compressor, Fig. 2 is a transverse sectional view showing the meshing state of the scrolls, and Figs. 3 and 4 are plan views showing the positional relationship between the Oldham ring and the Oldham key. longitudinal section,
5 and 6 are a plan view and a vertical sectional view showing the structure around the outer periphery of the end plate of an orbiting scroll according to the prior art, FIG. 7 is a plan view of the frame showing a broken closed container, and FIG. 8 is a A hydraulic pressure distribution diagram acting on the outer periphery of the end plate of the orbiting scroll is shown. 9 and 10 show one embodiment of the present invention, FIG. 9 is a plan view of a frame showing a broken closed container, and FIG. 10 is a vertical sectional view around the outer periphery of the end plate. Figure 11, 1st
FIG. 2 shows another embodiment, FIG. 11 is a plan view of the frame with the closed container cut away, and FIG. 10 is a longitudinal cross-sectional view of the outer periphery of the mirror plate. FIG. 13 is a plan view of an orbiting scroll showing another embodiment, FIG. 14 is an enlarged sectional view taken in the direction indicated by the - arrow in FIG. 13, FIG. An enlarged cross-sectional view is shown. FIG. 17 is a plan view of an orbiting scroll showing still another embodiment;
The figure shows an enlarged cross-sectional view taken along the - arrow in FIG. 17. FIG. 19 shows a longitudinal sectional view around the outer periphery of the end plate showing still another embodiment. FIG. 20 and FIG. 21 show still another embodiment, FIG. 20 is a plan view of the frame showing a broken closed container, and FIG. 21 is a vertical sectional view around the outer periphery of the end plate. FIGS. 22 and 23 show still another embodiment, with FIG. 22 being a plan view of the orbiting scroll, and FIG. 23 being a longitudinal cross-sectional view around the outer periphery of the end plate. DESCRIPTION OF SYMBOLS 1... Fixed scroll, 1f... End plate outer periphery of fixed scroll, 2... Orbiting scroll, 2a... End plate of orbiting scroll, 2f... End plate outer periphery of orbiting scroll, 4... Frame, 4b... Frame pedestal, 18
...Back pressure chamber, 30...Oldham ring, 31, 32...
Oldham key, 37...Oldham key groove, 50-5
3...Oil supply hole, 55-58...Oil supply hole, 60-63...
Oil supply groove, 40, 70... Radial oil supply passage, 80... Oil supply groove, 100, 101, 103, 104... Keyway.

Claims (1)

[Claims] 1. The scroll member has a fixed scroll and an orbiting scroll, and each of these pair of scroll members consists of an end plate and a spiral wrap standing upright on the end plate, and both scroll members are engaged with each other with the wraps inside, and the fixed scroll The outer periphery of the end plate of the orbiting scroll is sandwiched between the stationary member that fixes the frame and the end plate of the fixed scroll while maintaining a small gap, and the back pressure chamber at the back of the end plate of the orbiting scroll is filled with air between the frame and the end plate of the orbiting scroll. is equipped with an Oldham mechanism consisting of an Oldham key and a ring, and an orbiting scroll member is fitted to an eccentric shaft at the tip of the main shaft, and the orbiting scroll is rotated relative to a fixed scroll so that it does not apparently rotate on its own axis, creating a seal formed by both scroll members. space,
It is a device that compresses fluid by moving it from the outside to the center and reducing its volume.The lower end of the main shaft is immersed in lubricating oil, and an oil supply hole is drilled in the axial direction in the main shaft. A scroll in which an oil path is formed that communicates the bearing part provided in the orbiting scroll and the orbiting bearing part provided in the orbiting scroll with the oil supply hole, and leads to the frame chamber of the outer periphery of the end plate of the orbiting scroll through a gap between both bearings and a back pressure chamber. In the compressor, the frame chamber and the back pressure chamber on the outer periphery of the end plate of the orbiting scroll are communicated via an oil supply passage provided on the frame pedestal or the outer periphery of the end plate of the orbiting scroll, and the oil supply passage is connected to the sliding part of the Oldham mechanism. A scroll fluid machine characterized by being provided with a 2. The scroll fluid machine according to claim 1, wherein the oil supply passage is an oil supply hole provided in the frame pedestal. 3. The scroll fluid machine according to claim 1, wherein the oil supply passage is a oil supply groove provided in the frame pedestal. 4. The scroll fluid machine according to claim 1, wherein the oil supply passage is a oil supply hole provided on the outer circumference of the end plate of the orbiting scroll. 5. The scroll fluid machine according to claim 1, wherein the oil supply passage is a oil supply groove provided on the outer periphery of the end plate of the orbiting scroll.