JPH0544665A - Scroll compressor - Google Patents

Abstract

PURPOSE:To suppress the overload, noise and vibration due to the liquid compression and prevent the difficulty of start due to the liquid confinement, during the operation of a scroll compressor. CONSTITUTION:A compression mechanism 2 is equipped with a crankshaft 6, fixed swirl blade part 10, turning blade part 13, compression work space 14, turning end plate back surface 20, bearing part 21, etc., and further equipped with a restricting plane 23 for the shift in the axial direction and a restricting movable plane 26 for the shift in the axial direction, and urging-supported in the axial direction by an annular spring 28.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to prevention of overload due to scroll-type liquid compression and prevention of difficulty in starting a compressor due to liquid compression.

[0002]

2. Description of the Related Art A compression work space formed in a compression mechanism of a scroll compressor has a process of shrinking while its volume is sealed. Large pressure is generated by so-called liquid compression,
Break down the compression mechanism or stop the operation by overloading the compressor. Also, if the compression work space is clogged with liquid, it becomes difficult to start due to liquid compression. Various contrivances and inventions have been made to the unloading mechanism for eliminating the generation of this large pressure.

As a first conventional example of this unloading mechanism, reference is made to Japanese Patent Application Laid-Open No. Sho 62-28186 (Scroll Compressor).

FIG. 6 is a structural view of the scroll compressor disclosed in Japanese Patent Laid-Open No. 62-28186, and FIG. 7 is a sectional view of an eccentric drive portion of the scroll compressor.

In the figure, 101 is a fixed spiral blade component, 1
01a is a fixed spiral blade, 101b is a fixed end plate, 102 is a swirl spiral blade part, 102a is a swirl spiral blade, 102b.
Is a swirl end plate, and the fixed spiral blade 101a and the swirl spiral blade 102b mesh with each other to form a compression work space 103. Reference numeral 104 denotes a swivel drive shaft that drives the swirl spiral blade 102, and projects from the center of the rear surface of the swirl end plate. 105
Is a thrust bearing for supporting the swivel end plate 102b, and 106
Is a bearing component fixed to the fixed spiral blade component 101 with a bolt or the like, 107 is a rotation restraint component for preventing the rotation of the swirling spiral blade component 102, 108 is a crankshaft for driving the swirling spiral blade component 102, and 108a is its One spindle, 10
8b is a second spindle, and 109 is an oil hole. Reference numeral 110 denotes an eccentric drive bearing groove formed in the first main shaft 108a.
11 is slidably fitted in the eccentric drive bearing groove 110, and 112 is the eccentric bearing 111.
It is a spring that presses the outside of 10. The electric motor 113 includes a rotor 113a and a stator 113b. 114
Is a closed container, 115 is an oil pump, 116 is refrigerating machine oil, 117 is a suction pipe, 118 is a discharge hole provided in a fixed mirror plate, 119 is a discharge valve, 120 is a valve retainer, 121 is a discharge chamber, and 122 is a discharge pipe. .

In FIG. 6, ε indicates the amount of eccentricity from the axis O of the crankshaft 108 to the center Om of the rotary drive shaft 104, that is, the swirl radius of the swirl spiral blade component 102. When the crankshaft 108 is rotated in the direction of arrow A, the centrifugal force acting on the swirling spiral blade component 102 is fc, the compressive force is fg, and the resultant force is F. Further, the angle formed by the eccentric direction of the swirling spiral blade component 102 and the longitudinal direction of the eccentric drive bearing groove 110 is α, and the angle formed by the eccentric direction and the resultant force F is β. Under normal operating conditions, the component force F in the longitudinal direction of the groove F '= F
This spring is set so that cos (α + β) is less than the pressing force of the spring 112. When a large amount of liquid such as refrigerant liquid or refrigerating machine oil is sucked into the compression chamber and liquid compression is performed and the compression force fg is about to become extremely large, F ′ overcomes the pressing force of the spring 112 and the swing drive shaft swing radius ε. By moving in a direction to reduce the radial direction, the clearance in the radial direction at the closest portion of both spiral blades increases, and the compressive force is reduced.

As a second conventional example of the unload mechanism, reference is made to JP-A-60-69280.

FIG. 8 is a sectional view of a scroll compressor disclosed in Japanese Patent Laid-Open No. 60-69280, in which a compression mechanism 202 is provided inside a hermetic container 201, and a stator 2 of an electric motor is provided below the compression mechanism 202.
03 is fixed, and a lubricating oil sump 204 for accumulating lubricating oil is further provided below it. The compression mechanism 202 includes a fixed spiral blade component 207 having a fixed spiral blade 206 integrally formed on a fixed end plate 205, and the fixed spiral blade 206.
And a swirling spiral blade part 210 in which swirling swirl blades 208 are formed on a swirl end plate 209 to form a plurality of compression work spaces 211 by engaging with the swirl spiral blade part 210, and the swirl spiral blade part 210 is prevented from rotating and only rotates. Restraint parts 212
And a crankshaft 215 having an eccentric drive shaft 214 for eccentrically rotating the swivel drive bearing 213 provided on the swivel end plate 209, and a bearing component 219 for supporting the main shaft 216 with a main bearing 217.

Further, the fixed mirror plate flat surface 220 of the fixed mirror plate 205 on the rotary mirror plate side and the rotary mirror plate plane 221 of the rotary mirror plate 209 on the fixed mirror plate side are slidably brought into contact with each other, and the rotary mirror plate 109 is provided with a compression work space 211. The intermediate pressure holes 222 communicating with each other are provided, and the swirling spiral blades 208 of the swirling end plate 209 are provided.
The back pressure space 223 on the opposite side is maintained at an intermediate pressure between the discharge pressure and the suction pressure.

From the suction pipe 224 of the compressor to the compression mechanism 202
The refrigerant gas sucked in is compressed in the compression work space 211, then exits the discharge hole 225, passes through the peripheral passage 226 around the compression mechanism 202, and is discharged from the discharge pipe 227 to the outside of the compressor.

The lubricating oil in the lubricating oil sump 204 is the crankshaft 2
The main bearing 217, the eccentric drive shaft 214, and the orbiting drive bearing 213 from the eccentric oil supply passage 229 penetrating the main shaft 216 of No. 05.
Is communicated with the oil chamber 230 formed by the engagement.

The swirling spiral blade part 210 is fixed to the fixed end plate plane 220 by the pressure of the back pressure chamber 223 and the pressure of the oil chamber 230.
And is pressed against the contact surface of the swivel end plate flat surface 221 with an appropriate force.

[0013]

As described above, in the scroll compressor of the first conventional example referred to, if a large amount of liquid enters the compression work space 103 during operation, it will be in a so-called liquid compression state. As a result, as described above, the compression force fg tends to become extremely large. As a result, F ′ overcomes the pressing force of the spring 112 and the swing drive shaft 104 reduces the swing radius ε. To the compression workspace 103
The gap between the closest portions of the two spiral blades increases and the liquid leaks through this gap, and eventually the increase in the compression force fg is reduced. That is, the overload of the compressor and the generation of excessive pressure when sucking the liquid are suppressed. However, if the gap between the two blades increases during normal operation of the compressor, the compression efficiency of the compressor naturally lowers. Therefore, the range of suction pressure and discharge pressure of the compressor is normal and the compression work space 103 It is designed so that the gap between the closest portions of both spiral blades does not separate when a large amount of liquid is not sucked into. Therefore, the liquid compression pressure in the compression work space for starting the separation of the blade gap, the discharge pressure of the compressor, and the suction pressure are set to be considerably high. For this reason, it is not possible to set the liquid compression pressure at the time of liquid suction to a sufficiently low level, which causes considerable vibration and noise at the time of liquid suction, and the structural members of the compressor are not affected by these pressures. Must be designed to withstand the load.
Further, in the case of starting from a state in which the liquid is confined in the compression work space, there are drawbacks such that a high starting torque is required and a difficulty in starting easily occurs.

Further, in the above-mentioned second conventional example, a large movable gap in the rear direction of the swirling spiral blade part 208 is set to increase the pressure in the compression work space during liquid suction during operation. The axial contact between both spiral vane parts is separated, and the liquid leaks out there, so that liquid compression can be avoided. Similarly, the starting torque may be small for starting from the state where the liquid is confined in the compression work space 211. However, if the movable gap in the rear surface direction of the swirling spiral blade component 208 is increased, the swirling spiral blade component 208 moves in the rear surface direction at the time of starting because the pressure in the oil chamber 230 is low, and the space from the compression work space is reduced. There is a phenomenon that the leakage becomes large and the discharge amount of the gas is remarkably reduced, and the discharge pressure and the discharge amount are not increased. On the contrary, if the movable gap in the rear direction is made small, it is difficult to avoid liquid compression during operation and to start at the time of starting.

[0015]

A technical means for solving the problems of the conventional scroll compressor described above is to dispose an electric motor and a compression mechanism driven by the electric motor inside a hermetic container. This compression mechanism includes a fixed spiral vane component in which a fixed spiral blade is formed on a fixed mirror plate, and a swirl spiral vane formed on the swirl mirror plate to form a plurality of compression work spaces by meshing with the fixed spiral vane. A bearing having a component, a rotation restraint component that prevents rotation of the swirling spiral blade component and allows only the swirl, a crankshaft that swings and drives the spiral blade component, and a main bearing that supports a spindle formed on the crankshaft. Component, and the pressure of the gas discharged from this compression mechanism is applied to the space including the crankshaft and the electric motor, and on the back face of the turning end plate opposite to the turning spiral blade,
A swivel drive engagement part that engages with an eccentric drive engagement part provided on the crankshaft to drive the swirl spiral vane component to swivel is provided, and the gas pressure applied to the rear surface of the end plate is provided outside both of the engagement parts. A sliding partition ring for partitioning the discharge pressure applied to the center part and the pressure lower than the discharge pressure applied to the outer periphery of the back surface of the mirror plate is provided and formed on the bearing component or fixed to this, and the shaft on the back surface of the mirror plate is fixed to this. Axial movement restriction plane that limits the movable distance in the direction to a minute fixed gap is provided.Axial movement that limits the movable distance of the end plate back surface to a value smaller than the fixed gap outside this axial movement restriction plane. A limiting movable plane is provided so that the axial movement limiting movable plane can move in the direction of the axial movement limiting plane when the back surface of the end plate is pressed against the axial movement limiting movable plane by a strong axial force. To support it elastically.

[0016]

The operation of the present invention is as follows.

That is, when a large amount of liquid is sucked into the compression work space during operation of the compressor and the pressure in the compression work space becomes large, the swivel end plate is pressed against the axial movement restricted movable plane. The axial clearance of the spiral blade increases, the leakage from the compression work space increases, and this pressure decreases. When stronger liquid compression occurs, the back surface of the mirror plate strongly presses the axial movement restriction movable plane and moves toward the axial movement restriction plane, further increasing the axial gap between the spiral blade and the mirror plate, Prevents liquid compression pressure from becoming excessive. If the degree of liquid compression is reduced, the elastic force of the elastic support returns the axial movement limited movable plane to its original position, reducing the gap between the spiral blade and the end plate, and excessive leakage of compressed gas from the compression work space. To be prevented.

When a large amount of refrigerant liquid is present in the compression work space, the starting operation is also performed in the same manner to prevent the occurrence of the phenomenon that the discharge amount of the compressed gas does not increase after the starting operation.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As an embodiment of the present invention, FIG. 1 is a longitudinal sectional view of a scroll type electric compressor, FIG. 2 is a partially enlarged view of a compression mechanism portion of a first embodiment, and FIG. 3 is a first embodiment. 4 is a perspective view of the related parts of FIG. 4, FIG. 4 is a partially enlarged view of the second embodiment, and FIG. 5 is a partially enlarged view of the second embodiment.

The compression mechanism 2 is fixed inside the closed container 1,
The stator 4 of the electric motor 3 for driving the electric motor 3 is fixed to the upper side, the crankshaft 6 for driving the compression mechanism 2 is coupled to the rotor 5 of the electric motor 3, and the periphery of the compression mechanism 2 under the closed container 1 is lubricated. Use oil sump 7.

The compression mechanism 2 includes a fixed scroll vane component 10 having a fixed scroll vane 9 formed integrally with the fixed end plate 8 and a plurality of compression work spaces 1 which mesh with the fixed scroll vane 9.
4, the swirling spiral blade 11 forming the swirling spiral blade 11 on the swirling end plate 12, and the rotation restraining component 1 for preventing the swirling spiral blade component 13 from rotating and only rotating.
5, a swivel drive shaft 16 provided on the opposite side of the swirl vane 11 of the swirl end plate 12, and an eccentric bearing 17 provided inside the main shaft 18 of the crankshaft 6 into which the swivel drive shaft 16 is fitted.
And a main bearing 19 for supporting the main shaft 18 of the crankshaft 6.
And a flat plate part having an axial movement restricting plane 23 for restricting the axial movement of the swirling spiral blade part 13 with a minute gap from the end plate back surface 20 on the back surface of the swirling end plate 12. Place 24. A sliding partition ring 25 for partitioning the gas pressure applied to the end plate back surface 20 into a discharge pressure applied to the central portion and a pressure lower than the discharge pressure applied to the outer circumference of the end plate back surface 20 is disposed on the flat plate component 24. On the outer periphery of the flat plate component 24, an annular axial movement restriction movable flat surface 2 is provided.
A movable plane ring part 27 having 6 is arranged and is supported by an annular spring 28. Reference numeral 29 is a washer for smoothing the contact between the annular spring 28 and the movable plane annular component 27.

The refrigerant gas sucked from the suction pipe 30 of the compressor enters the compression mechanism 2 from the suction port 32 of the compression mechanism 2, is compressed in the compression work space 14, and is discharged from the discharge port 33 to the discharge chamber 3.
4, the discharge passage 35 provided on the outer periphery of the fixed end plate 8, the bearing component 2
It is discharged to a discharge chamber 37 below the electric motor between the electric motor 3 and the compression mechanism 2 through the discharge passage 36 provided in 1. The discharged refrigerant gas passes through the electric motor peripheral passage 38 and is guided from the discharge pipe 39 to the outside of the compressor.

In the embodiment shown in FIG. 4, an annular axial movement limiting movable flat surface 26 is provided on the outer periphery of the flat plate component 24, and the flat plate component is brought into contact with the rear face of the flat plate component 24 so that the end plate rear face 20 is in normal operation of the compressor. A movable plane ring component 27a having an inward cut 28a for ensuring a minute gap between the movable plane 26 and the axial movement restriction movable plane 26 is arranged, and is supported by an annular spring 28.

[0024]

As described above, the effect of the first aspect of the present invention is that when a large amount of liquid such as refrigerant liquid or lubricating oil is sucked into the compression work space during operation of the scroll compressor,
Due to the generated liquid compression pressure, the rear surface of the end plate of the swirling spiral blade part pushes the axial movement restriction movable plane and moves toward the axial movement restriction plane, preventing the generation of excessive liquid compression pressure and sucking the liquid. Noise and vibration are reduced, damage due to liquid compression is prevented without excessively strengthening the components of the compressor, and a small starting torque is required even when starting from a state where liquid is present in the compression work space. The present invention eliminates the defects of conventional scroll compressors such that the discharge pressure can be surely increased at the time of starting and the operation can be shifted to a stable operating state in addition to being capable of starting.

According to the second aspect of the present invention, the axial movement limiting plane is arranged around the central axis of the bearing component, and the annular axial movement limiting movable plane and the annular spring are provided near the outer periphery of this plane. By disposing the scroll compressor, the scroll compressor according to the first aspect can be realized at a small size and at a low cost.

The effect according to claim 3 of the present invention is that the flat plate component having the axial movement limiting plane is arranged around the central axis of the bearing component, and an annular step is provided on the outer circumference of this plane. The scroll compressor according to claim 1 can be realized in a small size and at a low cost by disposing the axial movement restricted movable plane and the annular spring.

[Brief description of drawings]

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

FIG. 2 is a sectional view of the same main part.

FIG. 3 is an exploded perspective view of the same main part.

FIG. 4 is a sectional view of a scroll compressor according to another embodiment of the present invention.

FIG. 5 is an exploded perspective view of the main part of the same.

FIG. 6 is a sectional view of a conventional example.

FIG. 7 is a plan sectional view of the same main part.

FIG. 8 is a sectional view of another conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 airtight container 2 compression mechanism 3 electric motor 4 electric motor stator 5 electric motor rotor 6 crankshaft 7 lubricating oil sump 8 fixed end plate 9 fixed spiral blade 10 fixed spiral blade part 11 swirl spiral blade 12 swirl mirror plate 13 swirl blade part 14 compression work space 15 rotation restraint parts 16 swivel drive shaft 17 eccentric bearing 18 main shaft 19 main bearing 20 swivel mirror plate rear face 21 bearing part 23 axial movement restricted plane 24 plane plate part 25 sliding partition ring 26 axial movement restricted movable plane 28 annular spring 30 suction Pipe 32 Suction port 33 Discharge port 34, 37 Discharge chamber 35, 36, 38 Discharge passage 39 Discharge pipe

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shuichi Yamamoto 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Masahiro Tsubokawa 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. 72) Inventor Sadao Kawahara 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (3)

[Claims] 1. A fixed spiral vane component in which an electric motor and a compression mechanism driven by the electric motor are arranged inside a closed container, and the fixed spiral plate has fixed spiral vanes formed on a fixed end plate, and the fixed spiral. A swirling spiral vane component formed on a swirling end plate with swirling spiral vanes meshing with the vanes to form a plurality of compression working spaces; A crankshaft for driving the spiral blade part to rotate, and a bearing part having a main bearing for supporting a main shaft formed on the crankshaft.
Discharge gas discharged from the compression mechanism into a space including the crankshaft and the electric motor, and engage an eccentric drive engagement portion provided on the crankshaft on a rear surface of the swivel mirror plate opposite to the swirl vane. Then, a swivel drive engagement portion that swivels and drives the swirl spiral blade component is provided, and a gas pressure applied to the rear surface of the mirror plate is provided outside the swivel drive engagement portion on the rear surface of the mirror plate,
A sliding partition ring for partitioning the discharge pressure applied to the center part and the pressure lower than the discharge pressure applied to the outer periphery of the back surface of the end plate is provided, and is formed on the bearing part or fixed to the bearing part and the back part of the end plate is fixed. Is provided with an axial movement limiting plane for limiting the axial movable distance to a minute fixed gap, and further, the axial movement limiting movable plane for limiting the movable distance on the rear surface of the end plate to a value smaller than the fixed gap. So that when the rear surface of the end plate is pressed against the axial movement limiting movable plane by a strong axial force, the axial movement limiting movable plane can be finely moved in the direction of the axial movement limiting plane. A scroll compressor that elastically supports this movable plane that limits axial movement. 2. A flat plate component having an axial movement limiting plane is fixed to a bearing component, and an annular movable plane ring component having an axial movement limiting movable plane is arranged in contact with the outer periphery of the axial movement limiting plane. An annular ring for urging the opposite side surface of the plane plate component and supporting the movable plane ring component between the bearing component and the surface of the plane plate component opposite to the axial movement limiting movable plane. The scroll compressor according to claim 1, further comprising a spring. 3. A flat plate component having an axial movement limiting flat surface is fixed to a bearing component, and is brought into contact with a surface of the flat plate component opposite to the axial movement limiting flat surface of the axial movement limiting movable flat surface. An annular movable plane ring component provided with an inner step for limiting the movement to the rear face of the end plate is arranged outside the plane plate component,
An annular spring for urging the movable flat ring component toward the flat plate component is provided between the bearing component and a surface of the movable flat ring component opposite to the axial movement limiting movable flat surface. Item 1. The scroll compressor according to Item 1.