JPS61218792A - Scroll compressor - Google Patents

Abstract

PURPOSE:To raise the durability and the compressing efficiency of a scroll compressor, by setting a discharge route control valve unit on the way of a discharge route, which has a form storage characteristic by which the discharge route is not opened until the temperature of this control valve unit gets higher than the preset value, and the discharge route is opened after it gets higher than the preset value. CONSTITUTION:A coil spring 37 is set on the upper side of a valve seat 36, and the outer coil spring 38 is set on the lower side of the valve seat 36, on both sides of a valve body 35, as they 37, 38 contact with the main body frame 2, and a discharge route control valve unit 34 which has a form storage characteristic by which a discharge route 39 is closed by the reaction force of the coil spring 37 and the self-weight of the valve body 35 when the temperature of the coil spring 38 is lower than the preset value, as the coil spring 38 contracts and does not energize the valve body 35 under this condition of temperature, and the discharge route 39 is opened when the temperature of the coil spring 38 rises above the preset value, as the coil spring 38 stretches and moves the valve body 35 upward, under this condition of temperature, is set on the main body frame 2. In this way, rise time of differential pressure oil feeding toward a back pressure chamber 20 is shortened, and the insufficiency of lubricating oil at the sliding part around the back pressure chamber 20 can be prevented, as the pressure of discharged refrigerant gas is increased and the temperature of the lubricating oil rises very rapidly, in the discharge space 24, after the compressor is started under the cool condition as being the discharge route 39 closed. Consequently, the durability and the compressing efficiency of the scroll compressor are raised.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a scroll compressor, and relates to improving compression efficiency at the initial stage of startup and durability of sliding surfaces.

BACKGROUND OF THE INVENTION In recent years, scroll compressors have been attracting attention as compressors with particularly low vibration and low noise characteristics.
As shown in Japanese Patent No. 49386, the compression principle as shown in FIG. 4 is used.

That is, the spiral-shaped orbiting scroll wrap 16 is engaged with the spiral-shaped fixed scroll lug 23, and the fluid sucked from the suction port is compressed by a pair of compressors formed between the fixed scroll wrap 23 and the orbiting scroll wrap 16. Confined within the chambers C1 and C2, the volume of the compression chamber is gradually reduced with the orbiting movement of the orbiting scroll wrap 16, and during this time the fluid is compressed to become a high pressure fluid. High-pressure fluid is discharged into the discharge chamber from the discharge port 25.

In addition, this type of compressor with a high-pressure gas-tight shell structure was invented with the configuration shown in FIG. 5, as known from Japanese Patent Laid-Open No. 57-73885, and a VC is provided to reduce the thrust force in the axial direction. The oil supply to the back pressure chamber and each bearing part was configured as follows.

That is, in FIG. 5, two fixed scroll knobs 22
3 is fixed to an end plate 221 attached to the main body frame 202 that supports the drive shaft 205, and the orbiting scroll wrap 2
16 is fixed to a lap support disk 215, and this lap support disk 215 is disposed loosely in a back pressure chamber 220 between an end plate 221 and a main body 7 frame 202, and is connected to an Oldham ring 218 having a rotation prevention function. It is rotatably supported by the main body frame 202, and a driving morph 21 is provided at each end.
0 and a drive shaft 205 having an eccentric portion.

The sucked and compressed gas is then discharged into the sealed shell 201. The lubricating oil separated from the discharged gas is sealed in the sealed shell 2.
The centrifugal force and differential pressure are collected in the oil reservoir at the bottom of the drive shaft 205, and are gradually reduced through the oil hole 206, which is eccentrically provided at the lower end of the drive shaft 205, and the small gap in the bearing that supports the drive shaft 205. The back pressure chamber 22 is maintained at an intermediate pressure using
This back pressure chamber 220 communicates with the suction chamber 220 through a balance passage 226 provided in the lap support disk 215 of the orbiting scroll, and communicates with the compression chamber 240, which is not connected to the suction chamber 220, and is balanced to an intermediate pressure state. The structure was such that the orbiting scroll was pressed against the fixed scroll to prevent both scrolls from separating due to the pressure of compressed gas.

Problems to be Solved by the Invention However, in the configuration of the oil supply passage as shown in FIG. 5 above, the discharge chamber is always in communication with the external piping system. The pressure in the back pressure chamber 220 communicating with the compression chamber 240 is higher than that in the
Moreover, since the viscosity of the lubricating oil is high, it is impossible to supply oil to each bearing part of the drive shaft 205 and each sliding part of the back pressure chamber 220, and the pressure inside the sealed shell 201 becomes higher than the pressure in the back pressure chamber 220. Furthermore, there is a problem in that during startup operation until the viscosity of the lubricating oil changes to the extent that it can pass through each bearing gap, the sliding surfaces may seize or abnormally wear, reducing the durability of the compressor.

In addition, immediately after a cold start, etc., there is no gas flowing into the back pressure chamber 220 through the bearing gaps of the oil sump 209 and the drive shaft 205, so the back pressure in the back pressure chamber 220 becomes lower than during steady operation.
Since the meshing of both scrolls was poor, there were problems such as a large compressed gas leakage gap and a low pressure 1ti91J ratio.

Therefore, the present invention provides a scroll compressor that has excellent compression efficiency and durability immediately after startup by speeding up the start-up characteristics of the entire oil supply system and speeding up the setting of appropriate back pressure in the back pressure chamber.

Means for Solving the Problems In order to solve the above problems, the scroll compressor of the present invention has a discharge passage leading to the lubricating oil supply source, which is provided with a mechanism on the downstream side that narrows the passage when the ambient temperature is below a set temperature. The discharge passage control valve device is provided with a shape memory characteristic to control the discharge passage to open the passage when the temperature exceeds the set temperature.

Effects of the present invention With the above-described configuration, the compressor starts when cold, the intake gas is compressed in the compression chamber, and when the discharge gas continues to be discharged into the closed shell whose discharge passage is blocked by the discharge passage control valve device, the closed shell is closed. The internal pressure and temperature are rapidly increased, allowing the lubricating oil in the oil reservoir to be quickly supplied to each bearing part of the drive shaft and the back pressure chamber, and the appropriate back pressure in the back pressure chamber can be set quickly. When the ambient temperature of the discharge passage control valve device exceeds the set temperature due to continued operation, the discharge passage is opened and communicated with the external piping system, resulting in a steady operation state and stable compression action and oil supply.

In addition, after the compressor is stopped, if the ambient temperature of the discharge passage control valve device falls below the set temperature, the discharge passage is blocked, preventing compressed fluid from flowing in from the external piping system and diluting the lubricating oil in the oil sump. Therefore, it is possible to provide a scroll pressure MI machine that is highly efficient and durable.

Embodiments Hereinafter, scroll compressors according to embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a longitudinal sectional view of a scroll refrigerant compressor in one embodiment of the present invention.

In Fig. 1, 1 is a sealed shell, 2 body frames are press-fitted into the sealed shell 1, and 3 and 4 are body frames 2.
5 is a drive shaft that is supported by bearings 3 and 4 and has an oil hole 7 that communicates with the oil 60 at a position opposite to the bearing 4. is provided with an eccentric shaft portion 8 whose lower end extends to and sinks into an oil sump 9 at the bottom of the sealed shell 1. Reference numeral 10 denotes a motor whose rotor 11 is press-fitted into a drive shaft 5 and a stator 12 into a sealed shell.

The wrap support disk 15 of the orbiting scroll 14 connected to the eccentric shaft 8 and having a bearing 13 at its center has an upright orbiting scroll wrap 16 integrally formed on its upper surface, and its lower surface is connected to the main body frame 2. It is supported by a thrust bearing seat 17 that protrudes into an open hole at the upper end. The orbiting scroll wraps 16 have a spiral planar shape, a rectangular longitudinal section, and adjacent orbiting scroll wraps 16 are in a parallel relationship.

The rotation-blocking Oldham ring 18 is a flat ring with parallel key-shaped keys perpendicular to each other on both sides thereof, and is provided between the lap support disk 15 and the thrust bearing seat 17. A part of the key on the upper surface side of this Oldham ring 18 is a key groove (
(not shown), a portion of the key on the lower surface side is fitted into a keyway 19 provided in the thrust bearing seat 17, and as the drive shaft 5 rotates, the bearing member 3 of the lug support disk 15 is moved to the drive shaft 6. A circular motion is made around the axis, and the orbiting scroll wrap 11 is orbited. In addition, the back pressure chamber 2 of the wrap support disk 15 is sealed by blocking the upper end opening hole on the upper end surface of the main body 7 frame 2.
The end plate 21 of the fixed scroll 33 set to 0 is mounted together with the thrust bearing seat 17 so as to sandwich the orbiting scroll 14 with a small gap. The end plate 21 is provided with an annular suction chamber 22 inside thereof, and further inside thereof is a fixed scroll wrap 23 which is parallel to the orbiting scroll wrap 16 and has the same shape and dimensions. A discharge port 25 with a discharge space 24 inside the hermetic seal 1 is provided in the portion, and a balance passage 27 that communicates the suction chamber 22 and the back pressure chamber 20 is provided in the lap support disk 15.

Orbiting scroll wrap 16 and fixed scroll wrap 23
As shown in Figure @4, two crescent-shaped compression chambers c1. c2 are formed, and these volumes narrow as one moves toward the center of the spiral, reaching a minimum in the final compression step.

Further, a suction pipe 28 passing through the sealed shell 1 from the side is connected to the annular suction chamber 22, and a discharge pipe 29 is connected to a side surface of the sealed shell 1 near the mork coil end 32. A groove 30 is provided on the outer surface of the main body frame 2 press-fitted into the sealed shell 1, and this groove 30 communicates the discharge space 24 on the end plate 21 side in the sealed shell 1 with the motor 1o side. . A discharge passage control valve device a4 is provided in the main body frame 2 near the discharge pipe 29, and controls communication between the discharge passage on the side of the mork coil end 32 and the passage of the discharge pipe 29. As shown in FIG. 2, this discharge passage control valve device 34 has a valve body 35 in between, a fill spring 37 above the valve seat 36 of the valve body 35, and a coil spring 38 below the valve seat 36.
is placed in contact with the main body frame 2, and the coil spring 38 contracts when its own temperature is below the set temperature and does not bias the valve body 35, but the reaction force of the coil spring 37 and the weight of the valve body 35 bias the valve seat. When the coil spring 3 closes the discharge passage 39 and its own temperature exceeds the set temperature, it expands as shown in FIG.
7 and the own weight of the valve body 35 to move the valve body 35 upward and open the discharge passage 39.

The operation of the scroll refrigerant compressor configured as described above will be described below with reference to FIGS. 1, 2, and 3.

First, FIG. 1 is a longitudinal sectional view of a scroll refrigerant compressor.

FIGS. 2 and 3 are longitudinal cross-sectional views for explaining the operation of the discharge passage control valve device. When the rotor 11 is rotated by the motor 1o and the drive shaft 5 is rotationally driven, the orbiting scroll 14 is rotated.
makes a whirling motion, and refrigerant gas is sucked into the suction chamber 22 through the suction pipe 28, and this refrigerant gas flows into two compression chambers c1. c2, and due to the orbiting movement of the orbiting scroll wrap 16, the compression chamber C1
, C2 is gradually reduced, and the refrigerant gas is compressed and discharged from the discharge port 25 into the discharge space 24 at the end of the compression process, and a part of the lubricating oil contained in the refrigerant gas is separated from the refrigerant gas by its own weight. The remaining lubricating oil is collected in the oil reservoir 9 at the bottom through the gap between the sealed shell 1 and the main body frame 2, and the remaining lubricating oil is carried out to the external refrigeration cycle through the discharge pipe 29 together with the discharged refrigerant gas.

However, when the ambient temperature of the discharge passage control valve device 34 is lower than the set temperature, the coil spring does not expand for 3 days and the valve body 35
The biasing of the coil spring 37 and the valve body 3 do not cause any force to operate.
5 closes the discharge passage 39 of the valve seat 36 portion. Therefore, the discharged gas is confined within the closed shell 1, and the pressure within the closed shell 1 increases rapidly, increasing the compression load. As a result, the compression of the refrigerant gas and the heat generation due to the morph input rapidly accelerate, and the heating of the discharged refrigerant gas increases at an accelerated pace, causing the ambient temperature of the discharge passage control valve device 34 to rise, and when the coil spring 38 exceeds the set temperature, the coil spring 38 The expansion causes the valve body 35 to actuate against the reaction force of the coil spring 370 and the weight of the valve body 35 to open the discharge passage 39 of the valve seat 36, and the discharged refrigerant gas is carried out to the refrigeration cycle through the discharge pipe 29.

On the other hand, a back pressure chamber 2 is formed in which the discharge space 24 is also isolated by the end plate 21 of the fixed scroll and the main body frame 2.
The lubricating oil in the oil reservoir 9 on the high-pressure side, which should be differentially supplied to the suction chamber 22 on the low-pressure side via 0, rises in temperature and becomes viscous until the discharge passage control valve device 34 opens its discharge passage 39. The bearing 3, which supports the drive shaft 5, improves fluidity by lowering the
4 and the eccentric shaft part 8, the pressure is gradually reduced by passing through the minute gap of the bearing part 13 of the eccentric shaft part 8, and the pressure is supplied to the back pressure chamber 20 at an intermediate pressure between the suction pressure and the discharge pressure, and lubricates each sliding surface.

Furthermore, the lubricating oil is applied to the lap support disk 1 of the orbiting scroll 14.
The refrigerant flows into the suction chamber 22 through the balance passage 27 provided in the refrigerant gas, and is again compressed and discharged together with the suction refrigerant gas.

According to this differential pressure oil supply system, the pressure in the back pressure chamber 2o on the back surface of the lap support disk 15 can be freely set from a pressure close to the discharge pressure to a pressure close to the suction pressure by adjusting the passage resistance of the oil supply passage. In the example, during steady operation, the gas pressure load acting on the back surface of the lap support @15 is slightly larger than the gas pressure load in the compression chamber, so that the lap support disk 15
The pressure in the back pressure chamber 2o is adjusted so that the thrust force acts on the side of the back pressure chamber 2o.

Further, after the compressor is stopped, when the ambient temperature of the discharge passage control valve device a4 decreases and the temperature of the coil spring 38 becomes below the set temperature, the coil spring 38 contracts and releases the bias against the valve body 35, and the reaction force of the fill spring 37 The valve seat 36 due to the weight of the valve body 35
The discharge passage a9 of the section is closed to cut off communication between the condenser side of the refrigeration cycle and the discharge space 24.

As described above, according to this embodiment, the discharge port 2 of the compression chamber
An oil reservoir 9 serving as a lubricating oil supply source is disposed in the middle of the discharge passage from 5 to the discharge pipe 29 at the compressor outlet, and a discharge passage control valve device 34 is disposed downstream thereof. When the temperature of the discharge passage 39 exceeds the set temperature, the passage 39 is opened, and when the temperature is below the set temperature, the passage 39 is closed. Since the discharge refrigerant gas pressure and the lubricating oil temperature in the oil reservoir 9 rise extremely quickly, the rise of differential pressure oil supply to the back pressure chamber 20, which is also lower than the discharge pressure, and the pressure setting of the back pressure chamber 20 can be accelerated. Therefore, there is no shortage of lubricant in the sliding parts around the back pressure chamber 20 immediately after a cold start.
It is highly durable, the meshing of both scrolls stabilizes quickly, the leak gap for compressed gas is small, and compression efficiency is high.

In addition, the compression load rises quickly due to the rise in discharge pressure, and the temperature of the discharged refrigerant gas rises quickly due to heat of compression of the refrigerant gas and heat generated by morph input. After opening the system, heating starts quickly in winter due to heat pump operation. In particular, with a scroll compression mechanism that does not require a discharge valve, the compression ratio is constant from a cold start, and the heat of compression during the gas compression process is stably secured, further speeding up heating operation.

In addition, after the compressor operation is stopped, the discharge passage control valve device 34 closes the discharge passage 39 when the temperature drops below the set temperature, so that liquefied refrigerant flows into the compressor from the condenser of the refrigeration cycle through the discharge pipe 29, and the lubricating oil in the oil sump 9 It is possible to prevent this from impairing the reliability of the compressor by diluting it and deteriorating the lubrication characteristics at the time of restart.

Further, according to this embodiment, the opening and closing of the discharge passage 39 of the discharge passage control valve device 34 is performed using the coil spring 38 having shape memory characteristics.
Since the coil spring 38 and the valve body 35 are separate bodies, the thermal capacity of the heat-responsive part is small, and the discharge passage 39 is opened and closed in response to changes in ambient temperature quickly, thereby opening and closing the discharge passage 39. It can improve compression efficiency and reliability by preventing unnecessary movement of refrigerant during start-up characteristics and after shutdown.

Further, according to this embodiment, since the discharge passage control valve device 34 is provided in the main body frame 2, the discharge passage control valve device 34 is provided in the main body frame 2.
4 includes not only the amount of compression heat generated by the discharged refrigerant gas but also the drive shaft 5.
The frictional heat of each tank moving part involved in the rotation is also transferred to accelerate the temperature rise of the discharge passage control valve device 34 and open the discharge passage 39 without much delay in the temperature rise of the discharged refrigerant gas.
Discharges the discharged refrigerant gas to the external refrigeration cycle to suppress abnormal pressure rise in the discharge passage and reduce compression efficiency.
◇ Effects of the Invention As described above, the present invention provides an oil sump space that serves as a KFi lubricating oil supply source in the middle of the discharge passage from the discharge port of the compression chamber to the discharge pipe of the compressor outlet, and this oil sump. A discharge passage control valve device is arranged on the downstream side of the space, and the discharge passage control valve device has a mechanism that does not open the discharge passage until its own temperature exceeds the set temperature, and opens the discharge passage when the temperature exceeds the set temperature. By having shape memory characteristics, fluidity improves quickly due to the pressure in the discharge passage after a cold start and the temperature of the lubricating oil increases, improving the differential pressure lubricating start-up characteristics to the back pressure chamber and each sliding part. Reliability in the early stages of start-up is achieved by improving the engagement of the scroll mechanism early to reduce wear loss on the sliding parts and quickly stabilize high-efficiency operation, and by stabilizing the lubricating oil by preventing re-inflow of compressed fluid after the compressor is stopped. It can improve sexual performance, etc., and
The thermal responsiveness of the discharge passage control valve device can be improved by operating the valve body by heat transfer to a spring device with shape memory characteristics to open and close the passage of the discharge passage control valve device, and by providing the discharge passage control valve device in the main body frame. The above effects can be further enhanced by increasing the

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a scroll refrigerant compressor according to a first embodiment of the present invention, and FIGS. 2 and 3 are detailed longitudinal cross-sectional views showing the operating state of the discharge passage control valve device in FIG. 4
The figure is a plan view illustrating the compression principle of the scroll refrigerant compressor, and FIG. 5 is a longitudinal sectional view of a conventional scroll gas compressor. 1... Sealed shell, 2... Body frame, 5... Drive shaft, 10... Morph,
14... Orbiting scroll, 15... Wrap support disk, 16... Orbiting scroll wrap, 2o... Back pressure chamber, 21... Mirror plate, 2
2...Suction chamber, 23...Fixed scroll wrap, 25...Discharge port, 27...
... Balance hole, 28 ... Suction pipe, 29 ...
...Discharge pipe, 33...Fixed scroll, 34
...Discharge passage control valve device, 35...
Valve L37, 38... Coil spring. Name of agent: Patent attorney Toshio Nakao and 1 other person/6
----1 Grass grain scroll lug ZS---a Main output ζ-F Fig. 5 fA Fig. 1 □□L ゛5----Running glaze

Claims (3)

[Claims] (1) An orbiting scroll wrap on a wrap support disk that is a part of the orbiting scroll is engaged with a spiral fixed scroll wrap formed on one surface of an end plate that is a part of the fixed scroll, and A suction chamber is formed on the outside, and the wrap support disk is formed between the main body frame that supports the drive shaft and the end plate, is pressure-blocked from the outside of the main body frame, and is connected to a lubricating oil supply source. is disposed in a loose state in a back pressure chamber that communicates directly or indirectly with the body frame and has a pressure lower than the pressure outside the body frame, and is rotatably supported via a rotation prevention mechanism of the lap support disk; A scroll compression mechanism is formed that compresses fluid by utilizing a change in volume of a compression chamber formed between a fixed scroll wrap and the orbiting scroll wrap, and discharge from a discharge port of the compression chamber to the outlet of the compressor is formed. An oil sump space serving as the lubricating oil supply source and a discharge passage control valve device on the downstream side of the oil sump space are disposed in the middle of the discharge passage up to the pipe, and the discharge passage control valve device has its own temperature. Scroll compressor with shape memory properties to open its passages when the temperature exceeds a set temperature and close or narrow said passages below a set temperature. (2) The scroll compressor according to claim 1, wherein the passage of the discharge passage control valve device is opened and closed by actuating a valve body using a spring device having shape memory characteristics. (3) The scroll compressor according to claim 1 or 2, wherein the discharge passage control valve device is provided in the main body frame.