JP2956294B2 - Scroll compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Since a compression working space formed in a compression mechanism of a scroll compressor has a process of reducing its volume while being sealed, when a large amount of liquid enters therein, Large pressure is generated by so-called liquid compression,
Destroy the compression mechanism or stop the operation by overloading the compressor. Further, if the compression working space is clogged with liquid, the starting operation becomes difficult due to liquid compression. Various devices and inventions have been made for an 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. 62-282186 (scroll compressor).

FIG. 6 is a structural view of a scroll compressor disclosed in Japanese Patent Application Laid-Open No. 62-282186, and FIG. 7 is a sectional view of an eccentric drive section of the scroll compressor.

In the drawing, reference numeral 101 denotes a fixed spiral blade part, 1
01a is a fixed spiral blade, 101b is a fixed end plate, 102 is a swirling spiral blade part, 102a is a swirling spiral blade, 102b
Reference numeral denotes a rotating end plate. The fixed spiral blade 101a and the rotary spiral blade 102b mesh with each other to form a compression work space 103. Reference numeral 104 denotes a turning drive shaft for driving the turning spiral blade 102, which protrudes from the rear center of the turning head plate. 105
Reference numeral 106 denotes a thrust bearing for supporting the turning head plate 102b.
Is a bearing part fixed to the fixed spiral blade part 101 with bolts or the like; 107 is a rotation restraining part for preventing the rotation of the rotary spiral blade part 102; 108 is a crankshaft for driving the rotary spiral blade part 102; One spindle, 10
8b is a second spindle, and 109 is an oil hole. Reference numeral 110 denotes an eccentric drive bearing groove formed on the first main shaft 108a,
11 is slidably fitted in the eccentric drive bearing groove 110, and 112 is the eccentric drive bearing groove 1
This is a spring that is pressed outward of the reference numeral 10. The electric motor 113 includes a rotor 113a and a stator 113b. 114
Is a sealed 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 end plate, 119 is a discharge valve, 120 is a valve holder, 121 is a discharge chamber, and 122 is a discharge pipe. .

In FIG. 6, ε denotes the amount of eccentricity from the axis O of the crankshaft 108 to the center Om of the turning drive shaft 104, that is, the turning radius of the turning spiral blade part 102. When the crankshaft 108 is rotated in the direction of arrow A, the centrifugal force acting on the swirling spiral blade part 102 is fc, the compressive force is fg, and the resultant force is F. The angle between 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 between the eccentric direction and the resultant force F is β. Under normal operating conditions, the longitudinal force F '= F ·
This spring is set so that cos (α + β) is equal to or less than the pressing force of the spring 112. When a large amount of liquid such as a refrigerant liquid or refrigerating machine oil is sucked into the compression chamber and liquid-compressed, and the compression force fg tends to be extremely large, F ′ overcomes the pressing force of the spring 112 and the turning drive shaft turns the turning radius ε. Is moved in the direction in which the spiral blades are reduced, the radial gap at the nearest portion between the two spiral blades is increased, and the compressive force is reduced.

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

FIG. 8 is a cross-sectional view of a scroll compressor disclosed in Japanese Patent Application Laid-Open No. 60-69280, in which a compression mechanism 202 is provided inside a closed vessel 201, and a stator 2 of an electric motor is provided below the compression mechanism 202.
03 is fixed, and a lubricating oil reservoir 204 is further provided below the lubricating oil reservoir 204. The compression mechanism 202 includes a fixed spiral blade part 207 having a fixed spiral blade 206 integrally formed on a fixed end plate 205, and a fixed spiral blade 206.
A swirling vane component 210 having a plurality of swirling vanes 208 formed on a revolving end plate 209 to form a plurality of compression working spaces 211 by meshing with the rotating swirl vane component 210. Restraint part 212
And a crankshaft 215 having an eccentric drive shaft 214 for eccentrically driving a slewing drive bearing 213 provided on the slewing head 209, and a bearing part 219 for supporting the main shaft 216 with a main bearing 217.

The fixed end plate plane 220 of the fixed end plate 205 on the turning end plate side and the turning end plate surface 221 of the turning end plate 209 on the fixed end plate side are slidably contacted with each other. An intermediate pressure hole 222 is provided to communicate with the swirling spiral blade 208 of the swiveling head plate 209.
Is maintained at a pressure intermediate between the discharge pressure and the suction pressure.

[0010] The compression mechanism 202 from the suction pipe 224 of the compressor.
Is compressed in the compression working space 211, 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 reservoir 204 is
05, a main bearing 217, an eccentric drive shaft 214 and a swing drive bearing 213.
Communicate with the oil chamber 230 formed by the engagement.

The swirling swirl vane part 210 is moved by the pressure of the back pressure chamber 223 and the pressure of the oil chamber 230 to the fixed end plate flat surface 220.
And the end surface of the revolving end plate 221 with appropriate force.

[0013]

As described above, in the first prior art scroll compressor referred to above, when a large amount of liquid enters the compression work space 103 during operation, a so-called liquid compression state is established. As described above, as a result, the compression force fg tends to increase significantly, and as a result, the direction in which F ′ overcomes the pressing force of the spring 112 and the turning drive shaft 104 reduces the turning radius ε. To the compression work space 103
The gap between the closest parts of the two spiral blades increases, and the liquid leaks through this gap, and as a result, the increase in the compressive force fg is reduced. That is, occurrence of overload and excessive pressure of the compressor at the time of liquid suction is suppressed. However, if the gap between the two blades increases during the normal operation of the compressor, the compression efficiency of the compressor naturally decreases, so that the range of the suction pressure and the discharge pressure of the compressor is normal and the compression work space 103 In the state where a large amount of liquid is not sucked into the spiral blade, it is designed so that the gap between the closest parts of the two spiral blades does not occur. Therefore, the liquid compression pressure in the compression working space where the separation of the blades starts and the discharge pressure and suction pressure of the compressor are set to be considerably high. For this reason, the liquid compression pressure at the time of sucking the liquid cannot be set sufficiently low, so that considerable vibration and noise are generated at the time of sucking the liquid, and the structural members of the compressor are subjected to the considerable liquid compression pressure and excessive pressure. It must be designed to withstand loads.
Further, in the case of starting from a state in which the liquid is confined in the compression working space, there are defects such as a high starting torque is required and starting is easily caused.

In the second conventional example described above, a large movable gap in the rear direction of the swirling swirl vane component 208 is provided to increase the pressure in the compression working space during liquid suction during operation. The axial contact between the two swirl vane parts is released, and the liquid leaks out here, so that liquid compression can be avoided. Similarly, the starting torque may be small for starting from a state in which the liquid is confined in the compression work space 211. However, if the movable gap in the rear direction of the swirling spiral blade component 208 is increased, at the time of starting, the pressure of the oil chamber 230 is low, so that the swirling spiral blade component 208 moves toward the rear surface and moves from the compression work space. Leakage becomes large, the discharge amount of the gas decreases remarkably, and a phenomenon occurs in which neither the discharge pressure nor the discharge amount increases as it is. Conversely, if the movable gap in the rear direction is made small, it will be difficult to avoid liquid compression during operation and start at the time of starting.

[0015]

The 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 closed container. This compression mechanism is composed of a fixed swirl blade part having a fixed swirl blade formed on a fixed end plate, and a swirl swirl blade formed on the swivel end plate with swirl swirl blades meshing with the fixed swirl blade to form a plurality of compression working spaces. A bearing having a component, a rotation restricting component that prevents only rotation of the swirling spiral blade component and only rotates, a crankshaft that drives the swirling blade component to rotate, and a main bearing that supports a main shaft formed on the crankshaft. Components, and the pressure of the gas discharged from the compression mechanism is applied to the space including the crankshaft and the electric motor.
A swivel drive engaging portion that engages with an eccentric drive engaging portion provided on the crankshaft to drive the swirling spiral blade component to swivel is provided.Outside these two engaging portions, a gas pressure applied to the rear surface of the head plate is provided. A sliding partition ring for partitioning a discharge pressure applied to the center portion and a pressure lower than the discharge pressure applied to the outer periphery of the rear surface of the head plate is provided, and is formed on the bearing component or fixed to this, and a shaft on the rear surface of the head plate. An axial movement limiting plane that limits the movable distance in the direction to a small fixed gap is provided, and an axial movement that limits the movable distance of the back of the head plate to a value smaller than the fixed gap outside the axial movement limiting plane. A limiting movable plane is provided so that when the rear surface of the head plate is pressed against the axial movement limiting movable plane by a strong axial force, the axial movement limiting movable plane can move in the direction of the axial movement limiting plane. It is elastic support.

[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 the operation of the compressor and the pressure in the compression work space increases due to the liquid compression state, the revolving head plate is pressed against the axial movement limiting movable plane. As a result, the axial clearance of the spiral blade is increased, so that the leakage from the compression working space is increased, and the pressure is reduced. When the liquid compression is further increased, the rear surface of the end plate strongly pushes the axial movement restriction movable plane to move toward the axial movement restriction plane, and the axial gap between the spiral blade and the end plate increases, The liquid compression pressure is prevented from becoming excessive. If the degree of liquid compression decreases, the axial movement limiting movable plane returns to the original position due to the elastic force of the elastic bearing, the gap between the spiral blade and the end plate decreases, and excessive leakage of compressed gas from the compression work space Is prevented.

The starting operation when a large amount of refrigerant liquid is present in the compression working space operates in the same manner, thereby preventing a phenomenon that the discharge amount of the compressed gas does not increase after the start.

[0019]

1 is a longitudinal sectional view of a scroll type electric compressor, FIG. 2 is a partially enlarged view of a compression mechanism of the first embodiment, and FIG. 3 is a first embodiment of the present invention. FIG. 4 is a partially enlarged view of the second embodiment, and FIG. 5 is a partially enlarged view of the second embodiment.

A compression mechanism 2 is fixed inside a closed container 1,
A stator 4 of a motor 3 for driving the motor 3 is fixed above, and a crank 5 for driving the compression mechanism 2 is connected to a rotor 5 of the motor 3 to lubricate the periphery of the compression mechanism 2 below the closed casing 1. The sump 7 is used.

The compression mechanism 2 includes a fixed scroll blade part 10 having a fixed scroll blade 9 integrally formed on a fixed head plate 8, and a plurality of compression working spaces 1 engaged with the fixed scroll blade 9.
A swirl-vane component 13 in which a swirl-vane 11 forming a part 4 is formed on a revolving head plate 12 and a rotation-restricting component 1 that prevents the revolving-vortex-blade component 13 from rotating and only turns.
5, a turning drive shaft 16 provided on the opposite side of the turning spiral blade 11 of the turning end plate 12, and an eccentric bearing 17 provided inside the main shaft 18 of the crankshaft 6 and into which the turning drive shaft 16 fits.
And a main bearing 19 for supporting a main shaft 18 of the crankshaft 6.
And a flat plate component having an axial movement limiting plane 23 for limiting the axial movement of the swirling spiral blade member 13 with a small gap from the mirror back surface 20 at the back of the rotating head plate 12. 24 is arranged. A sliding partition ring 25 for partitioning the gas pressure applied to the rear face 20 of the flat plate into a discharge pressure applied to the central portion and a pressure lower than the discharge pressure applied to the outer periphery of the rear face 20 of the head plate. An annular axial movement limiting movable plane 2 is provided on the outer periphery of the flat plate component 24.
A movable planar ring part 27 having a ring 6 is arranged and is supported by an annular spring 28. Reference numeral 29 denotes a washer for making the contact between the annular spring 28 and the movable planar ring component 27 smooth.

The refrigerant gas sucked from the suction pipe 30 of the compressor enters the compression mechanism 2 through the suction port 32 of the compression mechanism 2, is compressed in the compression working space 14, and is discharged through the discharge port 33 into the discharge chamber 3.
4. Discharge passage 35 provided on outer periphery of fixed head plate 8, bearing component 2
The fluid is discharged to a discharge chamber 37 below the motor between the electric motor 3 and the compression mechanism 2 through the discharge passage 36 provided in the motor 1. The discharged refrigerant gas passes through the 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 abutted on the outer periphery of the flat plate component 24, and the rear surface of the flat plate component is brought into contact with the rear surface of the end plate 20 during normal operation of the compressor. A movable flat ring part 27 a having an inner cut 28 a for securing a minute gap between the movable flat ring 26 and the movable plane 26 for limiting axial movement is arranged, and this is supported by an annular spring 28.

[0024]

According to the first aspect of the present invention, as described above, when a large amount of liquid such as refrigerant liquid or lubricating oil is sucked into the compression working space during operation of the scroll compressor,
Due to the generated liquid compression pressure, the back surface of the end plate of the swirling spiral blade part presses against the axial movement restriction movable plane and moves toward the axial movement restriction plane, preventing the generation of excessive liquid compression pressure and at the time of liquid suction. Reduces the noise and vibration of the compressor, prevents damage due to liquid compression without excessively strengthening the components of the compressor, and uses a small starting torque even when starting from the presence of liquid in the compression work space. The present invention solves the drawbacks of the conventional scroll compressor, such as being able to start, and allowing the discharge pressure to rise reliably at the time of starting to shift to a stable operation state.

According to a second aspect of the present invention, an axial movement limiting plane is arranged around the center axis of the bearing component, and an annular axial movement limiting movable plane and an 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 in a small size and at low cost.

According to a third aspect of the present invention, a flat plate component having an axial movement limiting plane is arranged around a central axis of a bearing component, and an annular step having an inner step is provided on the outer periphery of this plane. By disposing the movable plane for limiting axial movement and the annular spring, the scroll compressor according to the first aspect can be realized in a small size and at low cost.

[Brief description of the drawings]

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

FIG. 2 is a sectional view of an essential part of the same.

FIG. 3 is an exploded perspective view of the 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.

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

FIG. 7 is a plan cross-sectional view of the relevant part.

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Closed container 2 Compression mechanism 3 Electric motor 4 Electric motor stator 5 Electric motor rotor 6 Crankshaft 7 Lubricating oil reservoir 8 Fixed head plate 9 Fixed spiral blade 10 Fixed spiral blade part 11 Rotating spiral blade 12 Rotating blade plate 13 Rotating blade part 14 Compression work space REFERENCE SIGNS LIST 15 rotation restricting part 16 turning drive shaft 17 eccentric bearing 18 main shaft 19 main bearing 20 turning head back 21 bearing part 23 axial movement restriction plane 24 plane plate part 25 sliding partition ring 26 axial movement restriction 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

──────────────────────────────────────────────────続 き Continuing on the front page (72) Shuichi Yamamoto 1006 Kadoma Kadoma, Kazuma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Masahiro Tsubokawa 1006 Kadoma Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (72) Inventor Sadao Kawahara 1006 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-3-11182 (JP, A) (58) Fields investigated (Int. ⁶ , DB name) F04C 18/02 311

Claims (3)

(57) [Claims] An electric motor and a compression mechanism driven by the electric motor are provided inside a closed container, and the compression mechanism is composed of a fixed spiral blade part having a fixed spiral blade formed on a fixed head plate, and the fixed spiral blade. A swirling spiral blade part having a swirling spiral blade formed on a swiveling end plate that meshes with the blade to form a plurality of compression working spaces; a rotation restraining component that prevents only rotation of the swirling spiral blade part and only rotates; A crankshaft for rotating and driving the spiral blade part, and a bearing part having a main bearing for supporting a main shaft formed on the crankshaft,
Discharged gas from the compression mechanism is discharged into a space including the crankshaft and the electric motor, and is engaged with an eccentric drive engagement portion provided on the crankshaft on a rear surface of the endplate of the revolving headplate opposite to the revolving spiral blade. Then, a turning drive engaging portion for driving the turning spiral blade component to turn is provided, and the gas pressure applied to the rear surface of the head plate outside the turning drive engaging portion on the rear surface of the head plate,
A sliding partition ring for partitioning a discharge pressure applied to a center portion and a pressure lower than the discharge pressure applied to the outer periphery of the rear surface of the head plate is provided, and formed on the bearing component or fixed to the bearing component, and the rear surface of the head plate is fixed. An axial movement limiting plane for limiting the axial movable distance to a small fixed gap, and further, an axial movement limiting movable plane for limiting the movable distance of the rear surface of the head plate to a value smaller than the fixed gap. When the rear surface of the head plate is pressed against the axial movement limiting movable plane by a strong axial force, the axial movement limiting movable plane can move slightly in the direction of the axial movement limiting plane. A scroll compressor in which the axial movement limiting movable plane is elastically supported. 2. A flat plate part having an axial movement limiting plane is fixed to a bearing part, and an annular movable plane ring part having an axial movement limiting movable plane is disposed in contact with an outer periphery of the axial movement limiting plane. An annular ring for energizing the opposite side surface of the flat plate component and supporting the movable flat ring component between the bearing component and a surface of the flat 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 plane is fixed to a bearing component, and the flat plate component abuts on a surface of the flat plate component on the side opposite to the axial movement limiting plane. An annular movable planar ring component provided with an inner step for restricting movement to the rear surface of the end plate is disposed outside the planar plate component,
An annular spring for urging the movable flat ring component toward the flat plate component is disposed between the bearing component and a surface of the movable flat ring component opposite to the axial movement limiting movable flat surface. Item 2. The scroll compressor according to Item 1.