JP2002168182A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll compressor having an operating pressure as a high discharge pressure, preventing an increase in weight due to the secured strength of a fixed scroll and a rear casing and a decrease in the reliability and performance due to the excessive deformation of the fixed scroll with a discharge pressure and producing less leakage of a refrigerant. SOLUTION: A cutout 110 is provided in the outer periphery edge of an end plate portion 72 of the fixed scroll 70 to separate a peripheral area S2 in a space on the counter compression operating chamber side of the fixed scroll and a central area as a lower pressure space and a discharge pressure space P, respectively, to be sealed with sealing elements 92, 118 and a fastening element 102. A high pressure receiving area between the fixed scroll and the rear casing 90 is greatly smaller than in a conventional structure. Even if a compressor is used at a high discharge pressure, operating force due to a discharge pressure to the rear casing or the fixed scroll less increases and so an increase in the thickness of the rear casing or the fixed scroll or an increase in the size or weight of the compressor due to a material change is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a scroll compressor.

[0002]

2. Description of the Related Art In recent years, in view of the prevention of global warming, the shift from the current HFC134a to carbon dioxide (CO ₂ ), which has a low global warming potential, has been attracting attention as a refrigerant for vehicle air conditioning. R & D is being done.

When CO ₂ is used as a refrigerant, the operating pressure of the compressor is about 3 to 4 MPa on the low pressure (intake) side, and high pressure (discharge).
Side reaches 15Mpa, the working pressure when using HFC134a is about 8
It will be doubled. There is a demand for a compact, lightweight, and high-performance compressor that has sufficient pressure resistance against this very high internal pressure of the compressor.

Further, since CO ₂ has a smaller molecular weight than HFC134a, it easily permeates a rubber sealing material used as a current compressor sealing element, and leaks inside the compressor and leaks to the atmosphere. Therefore, from the viewpoint of ensuring performance and reliability, it is desired to reduce the leakage amount.

Hereinafter, a conventional scroll compressor will be described.
This will be described with reference to FIGS. FIG. 5 is an axial sectional view showing a scroll compressor, and FIG.
FIG. 7 is a cross-sectional view taken along line A (a cross-sectional view of
Is a view in the direction of arrow T in FIG. 5 (rear side view of a conventional compressor).
8 is a cross-sectional view taken along the line BB of FIG. 5 (a cross-sectional view of a high-pressure space of a conventional compressor).

Referring to FIGS. 5 to 8, a shaft 10 is rotatably provided with both ends supported by bearings 20 and 21 disposed in a front casing 80. The pressure is atmospheric and the compartment is sealed. Further, the shaft 10 has one end of the amateur part 2 to which the balance weight of the clutch 25 is added.
5a, and the other end is fitted and fixed to the bush 30 to which the balance weight 40 is fixedly added.
The balance weight 41 is fixed while being fixed to the inner ring of No. 1.

The orbiting scroll 60 has a bearing housing 61 on one end surface of the orbiting scroll head plate portion 62 and a spiral orbiting scroll wrap portion 63 for forming a compression working chamber S on the other end surface.

The orbiting scroll 60 has a bearing housing 61 fitted into the bush 30 via the bearing 22, and a key groove 64 and a slot plate 4 provided in the Oldham ring 45 and the orbiting scroll head 62.
A turning motion having a constant radius is allowed in a state where rotation is prevented by a key groove (not shown) provided in the motor 6.

The fixed scroll 70 has a spiral fixed scroll wrap portion 71 and a fixed scroll end plate portion 72 on the surface of the fixed scroll end plate 72 facing the compression chamber side space.
Near the center of the discharge valve 75 and discharge valve stop 7
8 has a discharge hole 74 provided incidentally, and is fitted and disposed on the inner peripheral surface of a front casing 80 having a suction port 82.

Further, in the fixed scroll 70, the peripheral surface of the fixed scroll wrap portion 71 and the peripheral surface of the orbiting scroll wrap portion 63 are moved without contact by the orbiting movement of the orbiting scroll 60, and the fixed scroll wrap portion 71 Has a minute gap in the axial direction with the orbiting scroll head plate portion 62, and the tip end surface of the orbiting scroll wrap portion 63 has a minute gap in the axial direction with the fixed scroll end plate portion 72 to form a plurality of compression working chambers S. To form

Further, a sealing element 76 is provided on the outer peripheral edge of the fixed scroll end plate portion 72 of the fixed scroll 70, and the compression chamber side space in the front casing 80 and the discharge port 9 are provided.
5 and a discharge pressure space P in a rear casing 90 having a space 5. A fixed scroll 70 is provided on the discharge pressure space side of the fixed scroll head 72 of the fixed scroll 70.
A boss portion 73 for fastening is provided, and a sealing element 92 is provided on a seat portion between the fastening element 102 and the rear casing 90 so as to partition and seal the discharge pressure and the atmospheric pressure in the rear casing 90 to perform fastening. The fixed scroll 70 and the rear casing 90 are fastened and fixed by the element 102.

In the rear casing 90, a sealing element 93 is provided on the insertion surface of the front casing 80, and the discharge pressure and the atmospheric pressure in the rear casing 90 are partitioned and sealed.
Furthermore, the rear casing 90 and the front casing 80 are fastened and fixed by the fastening element 100 disposed on the outer peripheral edge of the rear casing 90.

In such a configuration, when power is transmitted to the shaft 10 by the clutch 25 via an engine and a belt (not shown) as a driving source, a driving mechanism by the shaft 10 and the bush 30 and a rotation preventing mechanism by the Oldham ring 45 are provided. As a result, the orbiting scroll 60 performs a orbital motion of a constant radius, and the pressure of the refrigerant returned from the suction port 82 increases due to the volume reduction accompanying the operation of the compression working chamber S formed by the orbiting scroll 60 and the fixed scroll 70. The fixed scroll 70, the sealing element 76, the rear casing 90,
The sealing elements 92 and 93 are led out to the discharge pressure space P that is sectionally sealed and discharged from the discharge port 95 to the refrigeration cycle.

[0014]

However, in the above-described conventional configuration, CO ₂ is used as a refrigerant, and its operating pressure is
In the case of a very high working pressure of a low pressure of 3 to 4 Mpa and a high pressure of 15 Mpa, a front casing 80 and a rear casing 90 which are structural parts as a pressure vessel of the compressor are used.
In the above, the thickness of the front casing 80 made of a normal aluminum material whose internal pressure is low (suction pressure) and the rear casing 90 made of a normal aluminum material whose internal pressure is high (discharge pressure) are greatly increased. Alternatively, the material must be changed to an iron material having a higher strength than an aluminum material, resulting in an increase in the size or weight of the compressor.

In the fixed scroll 70, a fixed scroll end plate 72 facing the rear casing 90 side.
The discharge pressure acts on almost the entire surface of the compressor, and the sealing element 76 partitions and seals the suction pressure and the discharge pressure in the compression chamber side space, so that the operating pressure of the compressor (particularly discharge pressure) and the discharge pressure and the suction pressure As the difference increases, the fixed scroll end plate 72
The deformation of the fixed scroll wrap 71 increases accordingly.

As a result, the distal end face of the orbiting scroll wrap 63 of the orbiting scroll 60 and the fixed scroll end plate 7
The small gap in the axial direction between the scroll scroll wrap 63 and the peripheral surface of the scroll scroll wrap 63 and the peripheral surface of the fixed scroll wrap portion 71 cannot be smoothly moved. Abnormal wear on the peripheral surface of the orbiting scroll wrap portion 63 or the peripheral surface of the fixed scroll wrap portion 71, or the contact between the peripheral surface of the orbiting scroll wrap portion 63 and the peripheral surface of the fixed scroll wrap portion 71 is released. There is a concern that compressor performance may be degraded due to leakage in the compression working chamber S.

In order to avoid the inconvenience caused by the deformation of the fixed scroll 70, the thickness of the fixed scroll end plate portion 72 of the fixed scroll 70 usually made of aluminum material is greatly increased, or the strength is increased as compared with the aluminum material. Therefore, the material must be changed to an iron material having an excellent performance, which results in an increase in the weight of the compressor.

Further, fastening elements 10 such as four bolts for fixing the fixed scroll 70 and the rear casing 90 are provided.
2, the rear casing 90 and the front casing 8
The fastening elements 100 such as eight bolts for fixing the number 0 are increased in strength, for example, by increasing the number or size of the fastening elements with a large increase in the discharge pressure in the rear casing 90. Must be used, resulting in an increase in the number of parts of the compressor and an increase in manufacturing costs. .

Further, since the objects to be sealed of the sealing elements 76, 92 and 93, which are usually made of rubber material, are high-pressure and high-temperature discharge gas, the discharge pressure is greatly increased and CO
Combined with the high permeability of the rubber material of No. ₂ , there is a concern that the refrigerant leaks from the inside of the compressor to the atmosphere and the reliability is impaired.

The present invention has been made to solve the above-mentioned conventional problems, and suppresses an increase in the size and weight of the compressor even when the operating pressure of the compressor using CO ₂ as a refrigerant is high. It is an object of the present invention to provide a scroll compressor having high performance and high reliability while suppressing an increase in manufacturing cost.

[0021]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a fixed scroll having a suction pressure space in a peripheral area of a non-compression working chamber side space, and a central area partitioned and sealed in a discharge pressure space. It is.

According to the above configuration, the discharge pressure space partitioned and sealed by the fixed scroll and the rear casing is limited to only the central portion, and the pressure receiving area of the fixed scroll and the rear casing under high pressure is significantly larger than that of the conventional structure. Even when used at a high discharge pressure, the increase in the acting force on the rear casing and the fixed scroll is small. Therefore, it is possible to prevent an increase in the size and weight of the compressor due to an increase in the thickness of the rear casing and the fixed scroll and a change in material.

Further, since the deformation of the fixed scroll can be reduced, seizure, abnormal wear, and performance deterioration can be prevented.

Further, the number and size of the fastening elements for fixing the fixed scroll and the rear casing, and the fastening elements for fixing the rear casing and the front casing, and the increase in the number of parts of the compressor due to the increase in strength, and the manufacture thereof Costs can be prevented from rising.

Furthermore, since all the sealing pressures of the sealing element for partitioning and sealing the internal pressure of the compressor and the atmosphere can be set to the suction pressure which is the minimum pressure in the compressor, refrigerant leakage from the inside of the compressor to the atmosphere can be prevented. Can be reduced, and the reliability of the compressor can be secured.

[0026]

In order to solve the above-mentioned problems, a scroll compressor according to a first aspect of the present invention is a pressure vessel section such as a front casing or a rear casing for partitioning and sealing the atmospheric pressure and its internal pressure. A fixed scroll disposed and housed in the pressure vessel portion and having a discharge hole for discharging compressed gas in a central region; a plurality of fastening elements for fixing the fixed scroll to the pressure vessel portion; A orbiting scroll that orbits at a constant radius without cutting, and a cutout or a through hole is formed in the pressure vessel portion between the peripheral region of the counter-compression working chamber side space of the fixed scroll and the suction space of the compression working chamber. And the central region is partitioned and sealed in the discharge pressure space.

According to the structure of the first aspect, the peripheral region of the fixed scroll in the space opposite to the compression working chamber is a low pressure space, and only the central portion is the discharge pressure space. Since the area is significantly smaller than the conventional structure, the increase in the acting force on the rear casing and the fixed scroll is small even when used at a high discharge pressure. It has the effect of preventing the compressor from increasing in size and weight.

Further, since the deformation of the fixed scroll can be reduced, it has the effect of preventing seizure, abnormal wear and performance deterioration.

Further, in the scroll compressor according to the present invention, the inner region of the plurality of fastening elements for fixing the fixed scroll and the pressure vessel portion is partitioned and sealed in the discharge pressure space, and the outer peripheral side is partitioned and sealed in the suction pressure space. Make up.

According to the configuration of the second aspect, the sealing pressure of the sealing element between the fastening element fixing the fixed scroll and the rear casing and the rear casing, and the sealing pressure of the sealing element between the front casing and the rear casing are:
Low pressure (suction pressure), which is the lowest pressure in the compressor
Therefore, the sealing condition is relaxed, and the refrigerant has an effect of reducing the refrigerant leakage from the compressor to the atmosphere.

According to a third aspect of the present invention, there is provided a scroll compressor which divides a non-compression working chamber side space of a fixed scroll into a peripheral area and a central area,
The configuration uses a polymer elastic material or a metallic material made of a low gas permeable material.

According to the configuration of the third aspect, leakage of the refrigerant into the peripheral region (suction pressure space) of the discharge gas in the high pressure and high temperature state at the center portion of the fixed scroll on the side opposite to the compression working chamber is avoided, and the compression is prevented. It has the function of preventing performance degradation of the machine.

Further, in the scroll compressor according to the present invention, the seal element of the plurality of fastening elements for fixing the fixed scroll and the pressure vessel portion and the peripheral area of the counter-compression working chamber side space of the fixed scroll are defined as the suction pressure space. A sealing element for partitioning and sealing the central region to the discharge pressure space is formed integrally.

According to the structure of the fourth aspect, a plurality of sealing elements relating to a plurality of fastening elements for fixing the fixed scroll and the pressure vessel portion, and a peripheral area of the fixed scroll opposite the compression-compression-operating-chamber side are defined as a suction pressure space. The sealing element that partitions and seals the central area to the discharge pressure space can be formed by a single sealing element, which improves the workability of assembly, and the fastening element does not require high precision as a sealing surface, so it is inexpensive. Has the function of producing a fastening element.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1) FIG. 1 is an axial sectional view showing a scroll compressor according to Embodiment 1 of the present invention, and FIG. 2 is a sectional view taken along line BB of FIG. According to the embodiment of the present invention, the pressure distribution in the non-compression working chamber side space of the fixed scroll 70 which is arranged and housed in the rear casing 90 as the pressure vessel portion is shown in FIGS. Unlike the above, portions having the same configuration and operation and effect are denoted by the same reference numerals, detailed description thereof will be omitted, and different portions will be mainly described.

In the first embodiment of the present invention, the fixed scroll 70 is provided with a cutout 110 which communicates with the suction space S1 of the compression working chamber S at the outer peripheral edge of the fixed scroll head plate 72. Four boss portions 73 for fastening the fixed scroll are provided on the side of the portion 72 opposite to the compression working chamber.
Are formed. A rib 117 having the same shape as the rib 115 of the fixed scroll 70 is provided.
Is also provided in the rear casing 90, and a sealing element 118 is arranged so as to partition and seal inside the fastening element 102.

Therefore, a notch 110 is formed between the peripheral area S2 of the fixed scroll 70 on the side opposite to the compression working chamber and the suction space S1 of the compression working chamber S in the pressure vessel section composed of the front casing 80 and the rear casing 90. The central region is communicated with the discharge pressure space P and sealed.

According to the structure of the first embodiment, the pressure of the fixed scroll 70 in the non-compression working chamber side space is the discharge pressure space P only in the inner region of the seal element 118. The pressure receiving area of the high pressure is much smaller than that of the conventional structure, and the increase in the acting force due to the pressure on the rear casing 90 and the fixed scroll 70 can be reduced even when used at a high discharge pressure.

Accordingly, it is possible to prevent an increase in the size and weight of the compressor due to an increase in the thickness and a change in the material of the rear casing 90 and the fixed scroll 70. Further, since the deformation of the fixed scroll 70 can be reduced, seizure, abnormal wear, and performance deterioration can be prevented.

The number of fastening elements 102 for fixing the fixed scroll 70 and the rear casing 90 and the number of fastening elements 100 for fixing the rear casing 90 and the front casing 80, the size thereof, and the strength of the compressor are increased. Since an increase in the number of parts can be achieved with a minimum, an increase in manufacturing costs can be suppressed as much as possible.

Further, in the configuration of the first embodiment, the arrangement of the seal element 118 is particularly located inside the fastening element 102, so that the fixed scroll 70 and the rear casing 90
Pressure of the sealing element 92 between the fastening element 102 and the rear casing 90 for fixing the front casing 8 and the front casing 8
Since the sealing pressure of the sealing element 93 between the zero and the rear casing 90 is a low pressure (suction pressure), which is the lowest pressure in the compressor, the sealing conditions are relaxed, and leakage of refrigerant from the compressor to the atmosphere is reduced. it can.

In the first embodiment, as means for communicating the peripheral region S2 of the non-compression working chamber side space and the suction space S1 of the compression working chamber side at the outer peripheral edge of the fixed scroll 70,
As an example, a notch 11 is formed so that the fixed scroll 70 can be formed at the time of forming the material (die casting, forging, etc.).
Although 0 is provided, a similar effect can be obtained even if a through hole or notch is formed by machining or the like.

In the compressor according to the first embodiment, when CO ₂ is used as the refrigerant, the seal element 118 is made of a polymer elastic material or a metal material made of a material having low gas permeability. It has a configuration.

According to the structure of the first embodiment, leakage of the refrigerant into the peripheral area (suction gas space) of the discharge gas in the high pressure and high temperature state at the center in the space opposite to the compression working chamber of the fixed scroll is avoided. In addition, the compressor performance can be prevented from deteriorating.

(Embodiment 2) FIG. 3 is an axial sectional view showing a scroll compressor according to Embodiment 2 of the present invention, and FIG. 4 is a sectional view taken along line BB of FIG. This embodiment of the present invention is directed to the sealing element 1 according to the first embodiment.
18 and the seal element 92 are integrally formed as a seal element 119, which is different from the above-described conventional scroll compressor shown in the first embodiment and FIGS. The parts having the same effects are denoted by the same reference numerals, detailed description thereof will be omitted, and different points will be mainly described.

The sealing elements 119 were separately formed as shown in FIGS. 1 and 2 in the first embodiment.
A ring-shaped seal element 118 provided between the four fastening bosses 73 of the fixed scroll 70 and the rear casing 90 and located inside the fastening element 102, and the fixed scroll 70 and the rear casing 90 Fastening element 10 to be fixed
Four sealing elements 92 provided between the second casing 2 and the rear casing 90 are integrally formed as shown in FIG.

According to the structure of the second embodiment, the plurality of sealing elements 9 separately installed in the first embodiment are used.
2. The plurality of sealing elements 118 are combined into a single sealing element 11
Since only 9 is required, the workability of assembling the seal is improved, and the fastening element 102 does not require high precision as a sealing surface, and the fastening element can be manufactured at low cost.

[0049]

As is apparent from the above description, according to the first aspect of the present invention, a cutout or a communication hole is provided at the outer peripheral edge of the fixed scroll end plate portion of the fixed scroll, and the anti-compression operation of the fixed scroll is performed. Since the peripheral area of the room side space is partitioned and sealed in a low-pressure space, and the central area is partitioned and sealed in a high-pressure space, the pressure receiving area between the fixed scroll and the rear casing under high pressure is significantly smaller than that of the conventional structure. Even if the compressor is used at the discharge pressure, the increase in the acting force due to the discharge pressure to the rear casing and the fixed scroll is small, and the increase in the thickness and the material of the rear casing and the fixed scroll will increase the size and weight of the compressor. Can be prevented.

Further, since the pressure deformation of the fixed scroll can be reduced, seizure, abnormal wear and performance deterioration can be prevented.

Further, the number of fastening elements for fixing the fixed scroll and the rear casing, and the number of fastening elements for fixing the rear casing and the front casing, the increase in size, and the increase in the number of compressor parts due to the increase in strength are minimized. Production cost can be minimized.

According to the second aspect of the present invention, since the arrangement of the sealing element is particularly located inside the fastening element, the sealing element for fixing the fixed scroll and the rear casing and the sealing element for sealing the rear casing are sealed. Both the pressure and the sealing pressure of the sealing element between the front casing and the rear casing can be reduced to a low pressure, which is the minimum pressure in the compressor, so that the sealing conditions are relaxed, and refrigerant leakage from the compressor to the atmosphere can be reduced.

According to the third aspect of the present invention, since the material of the sealing element is made of a polymer elastic material or a metallic material made of a low gas permeable material in particular, the high pressure at the center portion in the space on the side opposite to the compression working chamber. High temperature state surrounding area of discharge gas
Leakage of refrigerant into the (suction gas space) can be avoided, and performance degradation of the compressor can be prevented.

According to the fourth aspect of the present invention, the seal element relating to the plurality of fastening elements for fixing the fixed scroll and the pressure vessel portion, and the peripheral region of the fixed scroll in the space opposite to the compression working chamber are defined as the suction pressure space. Since the seal element that partitions and seals the central region with the discharge pressure space is formed by a single seal element, the workability of assembly can be improved, and the fastening element does not require high precision as a seal surface. Fastening elements can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is an axial sectional view showing a scroll compressor according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line BB of FIG. 1 showing the scroll compressor.

FIG. 3 is an axial sectional view showing a scroll compressor according to a second embodiment of the present invention.

FIG. 4 is a sectional view of the scroll compressor, taken along line BB in FIG. 3;

FIG. 5 is an axial sectional view of a conventional scroll compressor.

FIG. 6 is a cross-sectional view of the scroll compressor taken along line AA of FIG. 5;

FIG. 7 is a view of the scroll compressor as viewed from an arrow T in FIG. 5;

FIG. 8 is a sectional view taken along the line BB of FIG. 5 showing the scroll compressor.

[Explanation of symbols]

 Reference Signs List 60 orbiting scroll 70 fixed scroll 74 discharge hole 80 front casing (pressure vessel section) 90 rear casing (pressure vessel section) 102 fastening element 110 notch 92, 118 sealing element 119 sealing element S compression working chamber P discharge pressure space S1 suction space S2 peripheral area

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3H029 AA02 AA16 AB03 BB44 BB53 CC02 CC19 CC54 3H039 AA02 AA04 AA12 BB01 BB05 BB15 BB28 CC03

Claims (4)

[Claims] 1. A fixed scroll having a pressure vessel section for partitioning and sealing the atmospheric pressure and its internal pressure, a fixed scroll disposed and housed in the pressure vessel section, and having a discharge hole for discharging compressed gas in a central region, and the fixed scroll. A plurality of fastening elements for fixing a scroll to the pressure vessel portion, and a orbiting scroll that meshes with the fixed scroll and rotates orbits at a constant radius without rotating, and in the pressure vessel portion, an anti-compression working chamber of the fixed scroll. A scroll compressor wherein a peripheral region of a side space and a suction space of a compression working chamber communicate with each other by a notch or a through hole, and a central region is partitioned and sealed in a discharge pressure space. 2. The scroll compressor according to claim 1, wherein the inner region of the plurality of fastening elements for fixing the fixed scroll and the pressure vessel portion is partitioned into a discharge pressure space, and the outer peripheral side thereof is partitioned and sealed into a suction pressure space. 3. The space of the fixed scroll on the side opposite to the compression working chamber is sectioned and sealed into a peripheral area and a central area, and a polymer elastic material or a metal material made of a low gas permeable material is used as a sealing element for the section sealing. The scroll compressor according to claim 1, wherein the scroll compressor is used. 4. A sealing element relating to a plurality of fastening elements for fixing the fixed scroll and the pressure vessel portion, and a peripheral area of the fixed scroll in a non-compression working chamber side space is partitioned into a suction pressure space and a central area is partitioned and sealed into a discharge pressure space. 3. The scroll compressor according to claim 2, wherein the seal element is formed integrally with the scroll compressor.