JPH0626470A - Scroll compressor - Google Patents

Abstract

PURPOSE:To improve reliablity by perfactly obtaining both compliance function and performance variable function, and exhibiting respective functions with certainty. CONSTITUTION:A support means 13 is provided for supporting a fixed scroll blade 12 movably in an axial direction. A back pressure guide means 14 is arranged on a back surface side of the fixed scroll blade, which guide means 14 is composed of a high pressure discharge chamber 22 for application of high pressure and a medium pressure chamber 23 for application of medium pressure, regulates axial movement of the fixed scroll blade under a normal operation, and allows axial movement of the fixed scroll for escaping gas inside a compressed space (a) when pressure inside the compressed space (a) is abnormally increased. A release mechanism 46 is communicated with the medium pressure chamber of the back pressure guide means, which mechanism 46 is opened in a release operation for introducing the medium pressure gas inside the medium pressure chamber to a suction part of a compressor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll type compressor having a variable capacity, which is used as a compressor constituting a refrigeration cycle of an air conditioner.

[0002]

2. Description of the Related Art For example, a compressor constituting a refrigeration cycle of an air conditioner has extremely low motion noise as compared with an ordinary rotary compressor, and a suction valve and a discharge valve are not required and the number of parts is small. There is a tendency for scroll-type compressors that are small in number and have good compression performance to be used frequently.

In this type of scroll compressor, the spiral blade of the fixed scroll blade and the spiral blade of the orbiting scroll blade are meshed with each other, and compression is performed between these blades and the end plate of each scroll blade. A space is formed, and the orbiting scroll blade is caused to orbit, so that the compressed gas is sucked into the compressed space, compressed, and discharged. Further, this type of compressor is characterized in that it is operated at a constant compression ratio regardless of load fluctuations.

However, varying the compression capacity of the compressor with respect to the air conditioning load is an effective means for air conditioning comfort and energy saving. For example, as in the refrigerant heating cycle, only by circulating the refrigerant during the heating operation, the compression ratio can be kept small.

Therefore, when the refrigerating cycle operation of the air conditioner is performed, it is necessary to provide a release mechanism for varying its capacity. The release mechanism temporarily takes out a part of the gas in the compression space, which is in the middle of compression, to the outside of the compressor and guides it to the suction section.

[0006]

By the way, the compression space of the scroll compressor is not always in a normal pressure state. For example, liquid back operation may be performed in which liquid refrigerant is sucked and compressed, and the compression space falls into an abnormally increased pressure state. If this state continues for a long time, a great stress is applied to the wing portion of each scroll wing, which may eventually break.

Therefore, recently, a fixed scroll blade is supported so as to be movable in the axial direction, and when the compression space is in an abnormally increased pressure state, a gap between the fixed scroll blade and the orbiting scroll blade is expanded to allow gas to escape, a so-called compliance function. Came to be adopted. However, considering the combined use of this compliance function and the release mechanism having the capability varying function, a new problem arises. That is, the release pipe that constitutes the release mechanism must be connected to the fixed scroll blade that is movable in the axial direction. Naturally, the release pipe penetrates the hermetic case that houses the compression mechanism portion and extends to the outside, and the position of the penetrating portion of the hermetic case is fixed.

Since the release pipe is originally a rigid body, the relative relationship between the penetrating portion of the closed case and the connecting position with respect to the fixed scroll blade does not change. That is, the movement of the fixed scroll blade is always restricted.

Therefore, it is conceivable to give some degree of flexibility to the release pipe by subjecting it to some processing or making it extremely thin, but this time, the rigidity of the pipe itself is lowered and the pipe is broken. It is easy to do, or it leads to problems such as complicated pipe shape and lengthening.

For these reasons, it is impossible for a refrigeration cycle equipped with a scroll compressor to have a compliance function in addition to a release mechanism having a variable capacity function. Not developed.

The present invention has been made by paying attention to the above circumstances, and an object of the present invention is to obtain a complete combination of a compliance function and a variable capacity function without any trouble and to ensure each function. The present invention is intended to provide a scroll type compressor that is highly effective in improving reliability.

[0012]

In order to satisfy the above object, the present invention provides

The spiral blade portion of the fixed scroll blade and the spiral blade portion of the orbiting scroll blade are engaged with each other, and a compression space is formed by these blade portions and the end plate portion of each scroll blade to form the orbiting scroll blade. A scroll-type compressor that swirls to suck a compressed gas into a compression space, compresses the gas, and discharges the gas. The scroll compressor includes a supporting unit that supports the fixed scroll blade so that the fixed scroll blade can move in the axial direction. To
It consists of a high-pressure discharge chamber that temporarily fills the high-pressure gas discharged from the compression space and an intermediate-pressure chamber that guides the intermediate-pressure gas that is being compressed.In normal operation, back pressure is applied to the fixed scroll blades to prevent axial movement. When the pressure in the compression space is regulated abnormally, the fixed scroll impeller is allowed to move in the axial direction to widen the clearance with the orbiting scroll impeller, and back pressure guide means for escaping gas in the compression space is provided. The scroll compressor is characterized by comprising a release mechanism which is connected to the intermediate pressure chamber of the means and which is opened during a release operation to guide the intermediate pressure gas in the intermediate pressure chamber to the compressor suction portion.

[0014]

According to this structure, since the back pressure guide means itself is fixed and the release mechanism is connected thereto, the fixed scroll blade can be freely moved in the axial direction. That is, the ability varying function and the compliance function are used together without any trouble.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

For example, a refrigeration cycle device which constitutes an air conditioner includes a scroll compressor A, a condenser B, and
The decompression device C and the evaporator D are connected via a refrigerant pipe P.

The scroll type compressor A will be described. In the figure, reference numeral 1 designates a hermetically sealed case, a support frame 2 is provided in an upper portion of the hermetically sealed case 1, and a rotary shaft 3 is rotatably supported. A compression mechanism section 4 described later is connected to the rotary shaft 3, and an electric motor section 7 including a stator 5 and a rotor 6 is provided in the lower portion.

The compression mechanism section 4 includes the support frame 2
The orbiting scroll blade 11 is rotatably supported via the Oldham ring 10, the fixed scroll blade 12 meshes with the orbiting scroll blade 11, and the supporting means 13 that supports the fixed scroll blade 12 so as to be movable in the axial direction. , And back pressure guide means 14 for exerting gas pressure on the back side of the fixed scroll blade 12. The Oldham ring 10 regulates the rotation of the orbiting scroll blade 11 and causes only the orbiting motion.

The orbiting scroll blade 11 has an end plate portion 11a having a boss portion 11c that engages with the upper end eccentric portion 3a of the rotary shaft 3, and a spiral-shaped end plate integrally projecting on the upper surface side of the end plate portion 11a. It consists of wings 11b.

The fixed scroll blade 12 has an end plate portion 12
a and a spiral blade portion 12b that is integrally projected on the lower surface side of the end plate portion 12a and meshes with the blade portion 11b of the orbiting scroll blade 11.

These orbiting and fixed scroll blades 11, 12
A pair of compression spaces a are formed by the end plate portions 11a, 12a and the blade portions 11b, 12b of the above, and the refrigerant gas that is the gas to be compressed is taken in from the peripheral end side and moves to the central part side and its volume is increased. It can be reduced and compressed.

On the other hand, a guide ring 27 is engaged with the peripheral end portion of the fixed scroll blade 12, and a guide pin 30 is inserted into the guide ring 27. The guide pin 30 is screwed to the support frame 2 and is connected to the guide ring 27.
Is held so that it can be displaced in the axial direction. In this way, the support means 13 is configured so that the fixed scroll blade 12 can be moved in the axial direction.

On the other hand, the upper surface of the fixed scroll end plate 12a is formed in a concave shape, and a discharge port 15 is provided in the center of the fixed scroll end plate 12a so as to communicate with the spiral center of the compression space a.

Further, on the upper surface side of the fixed scroll end plate portion 12a, with different radii about the discharge port 15,
Two ridges 16a and 16b are integrally provided, and a pair of intermediate pressure introducing holes 17 and 17 are provided here through the end plate portion 12a between the ridges 16a and 16b.

A back pressure plate 18 for partitioning the inside of the closed case 1 into an upper end space and a lower space is provided on the upper surface side of the fixed scroll blade 12 with a narrow gap between the upper ends of the protrusions 16a and 16b. It is attached and fixed to the case 1.

The back pressure plate 18 is provided with a valve seat portion 20 having a check valve 19 at the center thereof, and communicates with the discharge port 15. In other words, the discharge port 15 is the check valve 19
It communicates with the upper space of the back pressure plate 18 via the valve seat portion 20 provided with.

Around the valve seat portion 20 and the back pressure plate 18
The ridge 21a and the stepped portion 21b are provided on the lower surface side of the ridge 21a with a radius slightly larger than the radii of the ridges 16a and 16b provided on the fixed scroll blade 12.

Adjacent ridges 16a and 21a, 16b and 2
Seal rings 22a and 22b are respectively interposed between the 1b. Therefore, even if the fixed scroll blade 12 moves in the axial direction within the narrow gap with the back pressure plate 18, the seal between the adjacent ridges 16a and 21a, 16b and 21b becomes complete. ing.

The high pressure discharge chamber 22 into which the high pressure gas discharged from the compression space a is guided by the recessed portion provided around the discharge port 15 of the fixed scroll blade 12 and the back pressure plate valve seat 20.
Is formed and has a different radius and is formed between the adjacent ridges 16a and 21a, 16b and 21b, the intermediate pressure chamber 23 communicating with the intermediate pressure introducing hole 17 is formed.
Thus, the back pressure guide means 14 is constituted by these.

A release projection 18a is integrally provided on a part of the upper surface of the back pressure plate 18, and the release projection 18a communicates with the intermediate pressure chamber 23 and is opened to the side surface of the release projection 18a. A passage 40 is provided.

A release valve 42 elastically pressed and urged by a spring 41 is provided at the side opening end of the release passage 40.
It can be opened and closed freely. The other end of the spring 41 is supported by a receiving member 43, and a release pipe 44 is also connected thereto.

The release pipe 44 extends outside the closed case 1 and is connected to a refrigerant pipe P which is a suction portion of the compressor A. An electromagnetic opening / closing valve 45 is provided in the middle of the release pipe 44, and a release mechanism 46 is constituted by these.

In the scroll compressor thus constructed, when the electric motor section 7 is energized to drive the compression mechanism section 4, the low-pressure refrigerant gas evaporated in the evaporator D flows through the refrigerant pipe P. It is introduced into the closed case 1 through the space and fills the space below the back pressure plate 18.

This refrigerant gas is sucked into the outer peripheral side of the compression space a formed by the orbiting scroll blade 11 and the fixed scroll blade 12. Then, as the orbiting scroll blade 11 orbits, the orbiting scroll blade 11 is gradually transferred to the central portion and the space capacity is reduced, whereby the orbiting scroll blade 11 is compressed.

When the pressure rises to a predetermined pressure, the high pressure refrigerant gas is discharged from the discharge port 15 into the high pressure discharge chamber 22 and the valve seat portion 20.
The space above the back pressure plate 18 of the closed case 1 is filled via the. Further, it is guided to the external condenser B via the refrigerant pipe P.

In this condenser B, the high pressure refrigerant gas is condensed,
The liquid refrigerant is introduced into the decompression device C and adiabatically expanded. Further, it is guided to the evaporator D to evaporate, and exchanges heat with the air in the air-conditioned room introduced therein, thereby cooling the air-conditioned room.
The refrigerant gas evaporated in the evaporator D and having a low pressure is sucked into the compressor A again, and the above-described operation is repeated.

With the compression action in the compression space a, the high-pressure gas discharged from the discharge port 15 once fills the high-pressure discharge chamber 22, and a high back pressure is applied to the central portion of the fixed scroll blade 12. Call.

A part of the intermediate-pressure gas from the compression space a is introduced into the intermediate-pressure chamber 23 through the intermediate-pressure introduction hole 17, and fills the intermediate-pressure chamber 23, so that the peripheral end portion of the fixed scroll blade 12 is exposed to the intermediate-pressure gas. Apply back pressure.

In this way, the back pressure guide means 14 exerts an effective back pressure on the fixed scroll vane 12 in a normal operating state. The fixed scroll vane 12 is supported by the support means 13 so as to be movable in the axial direction, but its movement in the axial direction is restricted by the action of the back pressure guide means 14.
The clearance that forms the compression space a with the orbiting scroll blade 11 is maintained in an optimum state.

Depending on the operating conditions, the liquid refrigerant may be sucked into the compression space a, at which time the pressure is raised to an abnormally high pressure. The pressure in the compression space a exceeds the back pressure of the back pressure guide means 14, and the fixed scroll blade 12 moves in the axial direction.

The clearance of the compression space a formed with the orbiting scroll blades 11 is expanded, and the abnormal high-pressure gas in the compression space a escapes into the closed case 1. The stress of each scroll wing part 11b, 12b is released and a so-called compliance function is exhibited.

When the capacity is changed with respect to the air conditioning load during operation, the electromagnetic opening / closing valve 45 is opened and the release mechanism 46 is operated. That is, when the on-off valve 45 is opened by the signal from the cycle side, the release valve 42
Directly communicates with the suction section of the compressor A to generate a negative pressure.

The release valve 42 is provided in the release passage 40.
Is opened to communicate with the intermediate pressure chamber 23. The intermediate-pressure refrigerant gas filled therein is immediately guided from the release passage 40 to the release pipe 44, and high-pressure release is performed in the compression space a.

In order to ensure the compliance function during such a high pressure release, the high pressure discharge chamber 2 should have a thrust force larger than the thrust force generated in the compression space a.
It is necessary to set the area of 2.

Even if the compression space a is abnormally pressurized and the fixed scroll blade 12 is moved in the axial direction, the release pipe 44 is connected to the back pressure plate 18 fixed to the closed case 1, so that no influence is exerted. I do not receive it. That is, both the variable capacity function and the compliance function always work perfectly.

In the above embodiment, the release projection 42 is formed by integrally mounting the release valve 42 on the back pressure plate 18.
Although it is provided inside a, it is not limited to this.
You may make it show in.

That is, it may be a release mechanism 46A in which the release valve 42A is provided in the fixed scroll end plate portion 12a. In this case, one intermediate pressure introduction hole 17 is provided,
On the other hand, a release port 17a that connects the compression space a and the intermediate pressure chamber 23 is provided on the low pressure side of the compression process, and a new release valve 42A is accommodated therein in an openable and closable manner.

The release pipe 44 is connected to the release passage 40 provided in the release projection 18a to form the release mechanism 46A, and other configurations may be exactly the same as those of the embodiment described with reference to FIG. Here, the same numbers are assigned here and a new description is omitted.

When the electromagnetic on-off valve 45 is opened by a signal from the cycle side, the pressure in the intermediate pressure chamber 23 becomes the suction gas pressure, the release valve 42A opens the release port 17a, and the high pressure release in the compression space a. The fixed scroll vane 1
Even if 2 moves in the axial direction, there is no adverse effect on the release mechanism 46A.

Further, by providing the intermediate pressure introducing hole 17 on the high pressure side in the compression process with respect to the release port 17a, it is possible to greatly improve the release efficiency without impairing the compliance effect.

In any of the above-mentioned embodiments, by opening the electromagnetic opening / closing valve 45 at the time of startup,
The compression work can be reduced and the starting torque is reduced, which contributes to so-called energy-saving operation.

[0052]

As described above, according to the present invention, the supporting means for movably supporting the fixed scroll blade in the axial direction and the back pressure guide means for applying the high pressure and the intermediate pressure to the back side of the fixed scroll blade are provided. Since the compliance function consisting of and the release mechanism is connected to the intermediate pressure chamber that constitutes the above-mentioned back pressure guide means to perform the variable capacity function, the compliance function and the variable capacity function can be used perfectly without any trouble. Each function is surely exhibited, and reliability is improved.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a scroll compressor main part and a configuration diagram of a refrigeration cycle, showing an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of a scroll compressor main part and a configuration diagram of a refrigeration cycle of another embodiment.

[Explanation of symbols]

12 ... Fixed scroll blade, 12a ... End plate portion (of fixed scroll blade), 12b ... Blade portion (of fixed scroll blade), 1
Reference numeral 1 ... Orbiting scroll blade, 11a ... End plate portion (of orbiting scroll blade), 11b ... Blade portion (of orbiting scroll blade), a
... compression space, 13 ... support means, 22 ... high pressure discharge chamber, 23
... intermediate pressure chamber, 14 ... back pressure guide means, 46 ... release mechanism.

Claims (1)

[Claims] 1. A spiral scroll blade of a fixed scroll blade and a spiral blade portion of an orbiting scroll blade are meshed with each other, and a compression space is formed by these blade portions and an end plate portion of each scroll blade to form a swirling scroll. In a scroll type compressor in which a blade is swirled to suck a compressed gas into a compression space, and the compressed gas is discharged, a support means for supporting the fixed scroll blade so as to be axially movable, and a back surface of the fixed scroll blade. Side is composed of a high-pressure discharge chamber that temporarily fills the high-pressure gas discharged from the compression space and an intermediate-pressure chamber that guides the intermediate-pressure gas during compression.In normal operating conditions, back pressure is applied to the fixed scroll blades in the axial direction. Is regulated, and during abnormal pressure rise in the compression space,
Back pressure guide means for allowing the axial movement of the fixed scroll blade to widen the clearance with the orbiting scroll blade and allowing the gas in the compression space to escape, and to communicate with the intermediate pressure chamber, which is connected to the back pressure guide means. And a release mechanism that is opened during the release operation to guide the intermediate pressure gas in the intermediate pressure chamber to the suction portion of the compressor.