JPH07189934A - Scroll compressor - Google Patents

Abstract

PURPOSE:To keep an axial clearance at a micro-value and also eliminate any axial contact, by energizing a fixed scroll element toward a turning scroll, while sandwiching the fixed scroll element between its end plate and the turning scroll while keeping some axial clearance. CONSTITUTION:The turning scroll lap of a turning scroll is meshed with the fixed scroll element 7a of a fixed scroll 7 so as to make free rocking turn to define a volute compression space. And respective delivery outlets 27a, 27b are opened at the center of the fixed scroll element 7a and the endlate 7b and further, a suction chamber 38 is arranged on the outer side and a plurality of compression spaces are partitioned in the compression opening chamber to constitute the scroll compressing opening structure. The turning scroll is positioned between a main body frame for supporting a driving shaft and the fixed scroll 7. And fixed scroll element 7a is energized toward the turning scroll by an energizing means (back pressure chamber 28 connected to respective delivery outlets 27a, 27b), while the axial micro-clearance is kept.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art Conventionally, a scroll compressor having low vibration and low noise characteristics has a suction chamber on the outer periphery and a discharge port provided at the center of a spiral, and the flow of compressed fluid reciprocates in one direction. It is generally known that a discharge valve for compressing fluid such as a compressor or a rotary compressor is not required, the compression ratio is constant, the discharge pulsation is relatively small, and a large discharge space is not required.

Further, in order to further improve the vibration and noise characteristics, as a measure for reducing the jumping phenomenon of the orbiting scroll at the time of high speed operation of the compressor, etc., FIGS.
The configuration of is considered.

In FIGS. 3 and 4, the drive shaft 1
The end plate 1001a of the orbiting scroll 1001 that communicates with the drive pin 1007a at the tip of 007 is the fixed scroll 1.
It is supported by a minute gap between the end plate 1002a of 002 and the frame 1008, and the orbiting scroll 1001a jumps when the compression load, the inertial force of the rotating member, or the like changes at the time of starting, stopping, or high-speed operation of the compressor. And the orbiting scroll 1001 and the fixed scroll 1002.
A small gap in the axial direction is secured to seal the compression chamber to improve the compression efficiency and to prevent abnormal noise, vibration, and durability deterioration of sliding parts caused by collision between members (special features). JP-A-55-142902, US Pat.
94633 publication).

[0005]

However, since the conventional scroll compressor has a constant compression ratio, when the abnormal pressure rises in the compression chamber due to liquid compression or the like, the clearance between the compression chambers is widened to leak the compressed fluid. Since the pressure in the compression chamber cannot be lowered, there is a problem peculiar to the scroll compressor that the compression load increases, the parts break, and the sliding part durability decreases.

As a measure for solving the liquid compression problem, the structure shown in FIG. 5 is considered.

In FIG. 5, a fixed scroll 2001e is provided.
Is movable in the axial direction, the discharge pressure is introduced into the back pressure chamber 2015 by the biasing force of the leaf spring 2023e, and the back pressure causes the fixed scroll 2001e to rotate.
By pressing 1d to eliminate the axial gap between the orbiting scroll 2001d and the fixed scroll 2001e to seal the compression chamber, the compression efficiency is improved, and when liquid compression occurs in the compression chamber, the fixed scroll 2001e is the orbiting scroll. It is separated from 2001d in the axial direction to reduce the pressure in the compression chamber to reduce the load (US Pat. No. 3,600,114).

However, in the structure in which the fixed scroll 2001e is constantly pressed against the orbiting scroll 2001d, the fixed scroll 2001e is prevented from unnecessarily moving in the axial direction.
It is necessary to increase the urging force, friction and wear of both scroll contact surfaces, and further, friction and wear of the thrust load support surface that supports the non-fixed scroll side of the orbiting scroll 2001d reduce durability, and input loss also occurs. There was a big problem.

In response to the above problem, as shown in FIG. 3, the fluid pressure is introduced into the back chamber (opposite compression chamber side) of the orbiting scroll 1001 to press the orbiting scroll 1001 toward the fixed scroll 1002 ( Although there is a measure to reduce the thrust load acting on the orbiting scroll 1001, the axial distance between the contact surface of the orbiting scroll 1001 and the fixed scroll 1002 and the drive pin 1007a becomes large, so that the orbiting scroll 1001 can be overturned. This is apt to occur, and the orbiting scroll 1001 is twisted in the orbiting motion, resulting in an increase in input.

Also, as an overload prevention measure, US Pat. No. 381
Although a structure in which an orbiting scroll is moved in a direction perpendicular to the main shaft of the drive shaft as in Japanese Patent No. 7664 is also considered, it is difficult to improve vibration and noise characteristics due to a complicated component structure, and vibration and noise characteristics are improved. There has been a demand for a scroll compressor that can simultaneously reduce load and overload.

[0011]

In order to achieve the above object, a scroll compressor of the present invention is a fixed wrap which is rotationally locked to an end plate forming a part of a fixed scroll and is allowed to move only in an axial direction. A fixed scroll element consisting of a support disk and a spiral fixed scroll wrap is engaged with a scroll scroll wrap on a wrap support disk, which forms a part of an orbiting scroll, so that the scroll scroll wraps between the scrolls. Of the fixed scroll element, the discharge port is provided in the center portion of the fixed scroll element and the end plate, the suction chamber is provided on the outer side of the fixed scroll wrap, and the compression space is continuously shifted from the suction side toward the discharge side. The scroll compression mechanism is formed by being divided into the compression chamber of the main body and the orbiting scroll is arranged between the main body frame supporting the drive shaft and the fixed scroll. In addition, the wrap support disk is supported on the body frame on the side of the anti-compression chamber, the fixed scroll element is sandwiched between the end plate and the orbiting scroll, and the orbiting scroll is always maintained while maintaining a small axial gap. The urging means is provided so as to be urged in the direction.

Further, the scroll compressor of the present invention comprises a fixed wrap support disk which is rotationally locked to an end plate forming a part of the fixed scroll and is allowed to move only in the axial direction, and a spiral fixed scroll wrap. The orbiting scroll wrap on the wrap supporting disk that forms a part of the orbiting scroll is meshed with the fixed scroll element so as to oscillate and rotate, and a spiral compression space is formed between the two scrolls. Portion and end plate are provided with discharge ports, a fixed scroll wrap is provided with a suction chamber outside, and the compression space is divided into a plurality of compression chambers that continuously transition from the suction side toward the discharge side, and a scroll that compresses fluid The orbiting scroll, which forms the compression mechanism, is arranged between the main body frame supporting the drive shaft and the fixed scroll, and its wrap support disc is counter pressured. The chamber side surface is supported by the main body frame, and the biasing means is provided so that the fixed scroll element is sandwiched between the end plate and the orbiting scroll and is always biased in the orbiting scroll direction while maintaining a small axial gap. Along with this, the means for the fixed scroll element to be sandwiched between the end plate of the fixed scroll and the orbiting scroll and to maintain a minute gap in the axial direction is such that the fixed wrap support disk of the fixed scroll element is between the end plate and the main body frame. It is configured to come into contact with the height adjusting member sandwiched between the two and regulate the axial movement thereof.

Further, the scroll compressor of the present invention comprises a fixed wrap support disk which is rotationally locked to an end plate forming a part of the fixed scroll and is allowed to move only in the axial direction, and a spiral fixed scroll wrap. The orbiting scroll wrap on the wrap supporting disk that forms a part of the orbiting scroll is meshed with the fixed scroll element so as to oscillate and rotate, and a spiral compression space is formed between the two scrolls. Portion and end plate are provided with discharge ports, a fixed scroll wrap is provided with a suction chamber outside, and the compression space is divided into a plurality of compression chambers that continuously transition from the suction side toward the discharge side, and a scroll that compresses fluid The orbiting scroll, which forms the compression mechanism, is arranged between the main body frame supporting the drive shaft and the fixed scroll, and its wrap support disc is counter pressured. The chamber side surface is supported by the main body frame, and the biasing means is provided so that the fixed scroll element is sandwiched between the end plate and the orbiting scroll and is always biased in the orbiting scroll direction while maintaining a small axial gap. Along with this, the means for the fixed scroll element to be sandwiched between the end plate of the fixed scroll and the orbiting scroll and to maintain a minute gap in the axial direction is such that the fixed wrap support disk of the fixed scroll element is between the end plate and the main body frame. It is configured to abut on the height adjusting member sandwiched between the two so as to restrict its axial movement, and to fix the axial movement of the fixed lap support disk to the height adjusting member. It has been configured.

In the scroll compressor of the present invention, a spiral fixed scroll wrap formed on one surface of a mirror plate forming a part of a fixed scroll is swirled on a swirl wrap support disk forming a part of an orbiting scroll. The scroll wraps are oscillatably meshed to form a spiral compression space between the scrolls, a discharge port is provided in the center of the fixed scroll wrap, and a suction chamber is provided outside the fixed scroll wrap to create a compression space. Forms a scroll compressor that is divided into a plurality of compression chambers that continuously move from the suction side to the discharge side to compress the fluid, and the orbiting scroll is arranged between the main body frame that supports the drive shaft and the fixed scroll. Is
The orbiting lap support disc is supported by the thrust bearing surface of the main body frame, and a back pressure chamber formed by the orbiting wrap support disc and the main body frame is provided on the anti-compression side of the orbiting scroll and connected to the discharge side of the compressor. The oil separator and the back pressure chamber are connected by an oil return passage.

In the scroll compressor of the present invention, the spiral fixed scroll wrap formed on one surface of the end plate that forms a part of the fixed scroll is swirled on the swirl wrap support disk that forms a part of the orbiting scroll. The scroll wraps are rotatably engaged with each other to form a spiral compression space between both scrolls, a discharge port is provided in the center of the fixed scroll wrap, and a suction chamber is provided outside the fixed scroll wrap. The space is divided into a plurality of compression chambers that continuously move from the suction side to the discharge side to form a scroll compression mechanism that compresses the fluid, and the orbiting scroll is provided between the main body frame supporting the drive shaft and the fixed scroll. The orbiting wrap supporting disc is supported by the thrust bearing surface of the main body frame, and the orbiting wrap supporting disc and the book are provided on the anti-compression side of the orbiting scroll. A back pressure chamber formed by the frame is provided, and an oil return passage is connected between the oil separator connected to the discharge side of the compressor and the back pressure chamber, and is provided on the orbiting scroll wrap support disk. A swivel bearing that engages with the drive shaft is provided on the projection on the side opposite to the compression chamber, and a first annular seal member mounted in a first annular groove provided on the end surface of the projection and a thrust bearing surface of the main body frame are provided. The second annular seal member mounted in the provided second annular groove constitutes the back pressure chamber sealing means.

In the scroll compressor of the present invention, a spiral fixed scroll wrap formed on one surface of a mirror plate forming a part of a fixed scroll is rotated on a rotating wrap support disk forming a part of an orbiting scroll. The scroll wraps are rotatably engaged with each other to form a spiral compression space between both scrolls, a discharge port is provided in the center of the fixed scroll wrap, and a suction chamber is provided outside the fixed scroll wrap. The space is divided into a plurality of compression chambers that continuously move from the suction side to the discharge side to form a scroll compression mechanism that compresses the fluid, and the orbiting scroll is provided between the main body frame supporting the drive shaft and the fixed scroll. The orbiting wrap supporting disc is supported by the thrust bearing surface of the main body frame, and the orbiting wrap supporting disc and the book are provided on the anti-compression side of the orbiting scroll. A back pressure chamber formed by the frame is provided, and an oil return passage communicates between the oil separator and the back pressure chamber connected to the discharge side of the compressor, and the thrust bearing is provided outside the second annular groove. An oil groove is provided, and the oil groove and the back pressure chamber are communicated with each other by a throttle passage, and the low pressure side electric motor chamber housing the drive shaft and the electric motor is communicated with the oil groove.

In the scroll compressor of the present invention, the spiral fixed scroll wrap formed on one surface of the end plate that forms a part of the fixed scroll is swirled on a swirl wrap support disk that forms a part of the orbiting scroll. The scroll wraps are rotatably engaged with each other to form a spiral compression space between both scrolls, a discharge port is provided in the center of the fixed scroll wrap, and a suction chamber is provided outside the fixed scroll wrap. The space is divided into a plurality of compression chambers that continuously move from the suction side to the discharge side to form a scroll compression mechanism that compresses the fluid, and the orbiting scroll is provided between the main body frame supporting the drive shaft and the fixed scroll. The orbiting wrap supporting disc is supported by the thrust bearing surface of the main body frame, and the orbiting wrap supporting disc and the book are provided on the anti-compression side of the orbiting scroll. Provided back pressure chamber formed by the frame, with communicating with the oil return passage between the connected oil separator and the back pressure chamber to the discharge side of the compressor, the pressure in the back pressure chamber is
The orbiting scroll wrap support disc is set to be supported by the thrust bearing surface of the main body frame.

In the scroll compressor of the present invention, a spiral fixed scroll wrap formed on one surface of an end plate that forms a part of a fixed scroll is swirled on a swirl wrap support disk that forms a part of an orbiting scroll. The scroll wraps are rotatably engaged with each other to form a spiral compression space between both scrolls, a discharge port is provided in the center of the fixed scroll wrap, and a suction chamber is provided outside the fixed scroll wrap. The space is divided into a plurality of compression chambers that continuously move from the suction side to the discharge side to form a scroll compression mechanism that compresses the fluid, and the orbiting scroll is provided between the main body frame supporting the drive shaft and the fixed scroll. The orbiting wrap supporting disc is supported by the thrust bearing surface of the main body frame, and the orbiting wrap supporting disc and the book are provided on the anti-compression side of the orbiting scroll. A back pressure chamber formed by the frame is provided, and an oil return passage communicates between the oil separator and the back pressure chamber connected to the discharge side of the compressor, and the thrust bearing is provided outside the second annular groove. Is provided with an oil groove, and the oil groove and the back pressure chamber are communicated with each other by a throttle passage, the low pressure side electric motor chamber accommodating the drive shaft and the electric motor is communicated with the oil groove, and the back pressure chamber and the compression chamber are connected. The space between them is connected by a throttle passage provided in the orbiting scroll.

[0019]

According to the present invention, the orbiting scroll and the fixed scroll element tend to axially separate from each other due to the compression pressure of the compression chamber in which the pressure of the compression chamber is normal and sequentially shifts. When the compression load that is supported by the bearing surface and that acts in the axial direction of the fixed scroll element is smaller than the biasing force that acts on the fixed scroll element, a small gap is maintained in the axial direction between the orbiting scroll and the fixed scroll element. Keeps the compression chamber sealed to perform efficient compression, and the orbiting scroll is always supported by the thrust bearing surface of the body frame, even during a certain load change, acceleration / deceleration operation, or high speed operation. Prevents jumping and tilting of the orbiting scroll, and continues quiet compression operation with less vibration.

In the unlikely event that liquid compression occurs and the pressure in the compression chamber rises abnormally instantaneously, the compression load acting in the axial direction of the fixed scroll element becomes larger than the urging force acting on the fixed scroll element. The fixed scroll element moves in a direction that reduces the axial gap between the fixed scroll and the end plate of the fixed scroll, and the axial gap between the orbiting scroll and the fixed scroll increases. As a result, the compression chamber is unsealed, the pressure in the compression chamber drops, the compression load is reduced, normal compression operation is resumed, power loss is reduced, and the compressor is damaged and the sliding parts are worn. Therefore, an efficient scroll compressor excellent in vibration, noise and durability is provided.

Further, according to the present invention, the dimension of the height adjusting member is adjusted according to the height dimension of the fixed scroll wrap of the fixed scroll element and the orbiting scroll wrap of the orbiting scroll which are extremely important for sealing the compression chamber. Ensure a small axial gap.

According to the present invention, the fixed scroll element receives a fluid biasing force from the back pressure chamber B located at the center of the fixed scroll element due to the pressure of the discharge chamber, so that the central portion of the fixed lap supporting disk is slightly closer to the compression chamber. Transforms into. As a result, the axial clearance of the compression chamber having a high compression pressure in the vicinity of the discharge port A is reduced, and the sealing effect of the compression chamber is enhanced.

Further, according to the present invention, the high pressure lubricating oil is supplied to the back pressure chamber A from the oil separator connected to the discharge side of the compressor, and the pressure thereof acts on the thrust bearing surface via the orbiting scroll. Reduce.

Further, according to the present invention, the first annular seal member and the second annular seal member seal the back pressure chamber to enhance the sealing performance of the back pressure chamber A. As a result, even when the amount of oil returning from the oil separator to the back pressure chamber A is small, fluid leakage to the sliding portion around the back pressure chamber A is eliminated, and the back pressure action on the orbiting scroll is maintained.

Further, in the present invention, the differential pressure oil supply path from the back pressure chamber A to the motor chamber via the thrust bearing surface is formed by a simple means, and the lubricating oil flowing through this oil supply passage is supplied to the thrust bearing surface. , A sufficient oil film is formed on the sliding part.

Further, in the present invention, the orbiting scroll wrap supporting disk is supported on the thrust bearing surface of the main body frame.
Then, the orbiting scroll makes an orbiting motion on a plane that is always perpendicular to the main axis of the drive shaft. As a result, a smooth swing drive mechanism can be obtained in which one-sided sliding does not occur between the swing bearing and the swing shaft.

Further, according to the present invention, the lubricating oil in the back pressure chamber flows into the compression chamber through the throttle passage provided in the orbiting scroll, and the oil film thereof seals the compression chamber gap.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A scroll compressor according to an embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1 and FIG. 2, reference numeral 1 designates an iron-made hermetic case, the entire interior of which is in a low-pressure atmosphere communicating with the suction pipe 2, the motor 3 is arranged in the lower portion, and the compression portion is arranged in the upper portion. A fixed scroll 7 is attached via a spacer 6 to a main body frame 5 of a compression portion that supports a drive shaft 4 fixed to 3a.

The main body frame 5 is fixed to the closed case 1. The drive shaft 4 is supported by a main bearing 8 of a main body frame 5 and a sub bearing 9 of an auxiliary frame 8 attached to the hermetic case 1, and a honey pump device 10 is provided at the lower end of the drive shaft 4 to penetrate an oil sump 11. is doing. The vertical oil hole 12 provided in the drive shaft 4 has one end at the honey pump device 1.
0, and the other end branches into an oil hole A12a and an oil hole B12b. Oil hole A12a leads to the main bearing, oil hole B12b
Communicates with the orbiting bearing 14 to which the drive shaft 4 and the orbiting scroll 13 are slidably coupled.

The orbiting scroll 13 which meshes with the fixed scroll 7 to form the compression chamber 5 is composed of a orbiting scroll wrap 13a and a lap support disk 13b in which an orbiting bearing boss 13c is upright.

A first annular groove 17 is provided at the lower end of a slewing bearing boss 13c having a slewing bearing 14 which is eccentric from the main shaft of the drive shaft 4 and engages with a slewing shaft 16 provided at the upper end of the drive shaft 4.
Is provided, and the first annular seal member 18 is mounted in the first annular groove 17. First annular seal member 18
Is in sliding contact with the bottom surface of the recessed hole in the upper portion of the main body frame 5.

Lap support disk 13 of orbiting scroll 13
A second annular groove 20 is provided on the thrust bearing surface 19 of the main body frame 5 that supports b, a second annular seal member 21 is mounted in the second annular groove 20, and an oil groove 22 is provided on the outer side thereof. It is provided.

Lap support disk 13 of orbiting scroll 13
A space surrounded by b, the orbiting bearing boss 13c, and the main body frame 5 forms a back pressure chamber A23 of the orbiting scroll 13, and is sealed by the first annular seal member 18 and the second annular seal member 21. ing.

The fixed scroll 7 meshes with the orbiting scroll 13 to form the compression chamber 15, and the fixed scroll element 7 is formed.
The fixed scroll element 7a includes a spiral fixed scroll wrap 7c, a fixed wrap support disk 7d for supporting the fixed scroll wrap 7c, and a rear boss portion 7e.

In the pin hole 24 provided in the fixed wrap support disk 7d, a pin attached to the end plate 7b of the fixed scroll 7 is arranged so that the fixed scroll element 7a moves axially with respect to the end plate 7b but does not rotate. The tip of 25 is inserted.

The fixed scroll element 7a is provided by a plurality of springs 29 mounted on the end plate 7a so that an axial gap is always created between the fixed scroll element 7a and the end plate 7b.
Is pressed toward the orbiting scroll 13 and the end plate 7
The fixed wrap support disk 7d comes into contact with the end surface of the spacer 30 that is mounted inside a and comes into contact with the spacer 6, whereby the movement of the fixed scroll element 7a is restricted,
There is no axial contact between the fixed scroll element 7a and the orbiting scroll 13.

Back boss portion 7e of fixed scroll element 7a
A ring-shaped seal member (O-ring) is attached to the outer peripheral portion of the fixed lap support disc 7d and the end plate 7b. An annular seal member (O-ring) separates the back pressure chamber B28 formed by 7d and the end plate 7b from the outer peripheral portion of the fixed lap support disk 7d.

A check valve 31 is arranged at the opening end surface of the discharge port 27b of the end plate 7a, and a discharge chamber 32 is arranged adjacent to the check valve 31 on the upper face of the end plate 7a, and a discharge pipe 33 attached to the closed case 1 is provided. Communicate with the discharge chamber 32.

The discharge pipe 33 is pipe-connected to an oil separator (not shown) arranged outside the compressor, and this oil separator is connected to an orbiting scroll 13 via an oil return pipe 34 penetrating the sealed case 1. To the back pressure chamber A23.

A suction chamber 38 is provided on the outer peripheral portion of the fixed scroll wrap 15a, and the suction chamber 38 communicates with the suction pipe 2.

The back pressure chamber A23 communicates with the compression chamber 15 through two injection holes 39 having throttle passages provided in the lap support disk 13b of the orbiting scroll 13. The two injection holes 39 are provided in the compression chamber 15
The discharge ports (27a, 27a)
It is provided in an asymmetrical position around b). That is, one injection hole 39 is provided on the side closer to the suction chamber 38 with respect to the compression space on the side closer to the suction pipe 2 or the motor chamber 37 as the suction path.

Illustration of the main body frame 5 One end of the oil hole 21 provided in the bearing surface 19 communicates with the back pressure chamber A23 through the throttle passage 35 provided in the main body frame 5, and the oil hole 21
The other end of is connected to a motor chamber 37 that houses the motor 3 through an oil hole 36 provided in the main body frame 5.

A spiral groove is provided at the tip of the fixed scroll wrap 7c, and a spiral seal member 40 is mounted in the groove. The seal member 40 is in contact with the lap support disk 13b of the orbiting scroll 13.

On the other hand, the tip of the orbiting scroll wrap 13a of the orbiting scroll 13 has a minute gap capable of sealing the compression chamber 15 with respect to the fixed wrap support disk 7d of the fixed scroll element 7a.

The Oldham ring 41 for preventing rotation of the orbiting scroll meshes with the orbiting scroll 13 and the main body frame 5.

The operation of the scroll refrigerant compressor configured as described above will be described.

In FIGS. 1 and 2, when the drive shaft 4 is rotationally driven by the motor 3, the orbiting scroll 13 supported by the thrust bearing surface 19 of the main body frame 5 makes an orbiting motion to lubricate the refrigeration cycle connected to the compressor. The suction refrigerant gas containing oil flows into the suction chamber 38 via the suction pipe 2, is compressed and transferred to the compression chamber 15 formed between the orbiting scroll 13 and the fixed scroll 7, and is discharged in the central portion. It is discharged into the discharge chamber 32 through the outlet A27a and the discharge port B27b.

When the suction refrigerant gas containing the lubricating oil flows into the suction chamber 38, a part of the lubricating oil flows into the motor chamber 37 and flows down while cooling the motor 3 and the oil sump 1 at the bottom.
Collect to 1.

The discharge refrigerant gas containing the lubricating oil is discharged into the discharge pipe 33.
Oil separator (not shown) connected to the outside of the compressor via
And is discharged to the refrigeration cycle piping system.

The lubricating oil in the discharged refrigerant gas separated by the oil separator returns to the back pressure chamber A23 of the orbiting scroll 13 through the oil return pipe 34.

The orbiting scroll 13 is the fixed scroll 7
It is pressed against the thrust bearing surface 19 of the main body frame 5 by meshing with and compressing the refrigerant gas, but since the thrust load is reduced by the back pressure of the lubricating oil in the back pressure chamber A23, the friction loss is reduced.

The fixed scroll element 7a is prevented from separating from the orbiting scroll 13 by the discharge gas pressure of the back pressure chamber B28 of the fixed scroll element 7a communicating with the discharge port A27a and the discharge port B27b and the biasing force generated by the spring 29. , The compression chamber is sealed tightly. However, the fixed scroll element 7a is restricted from moving in the axial direction by the spacer 30,
There is no direct axial contact between the fixed scroll element 7a and the orbiting scroll 13.

The lubricating oil in the back pressure chamber A23 is the main body frame 5
Of the low pressure side motor chamber 3 through the oil passage 36 after being depressurized and flowing into the oil groove 22 of the thrust bearing surface 19.
The oil is differentially refueled at 7 and collected in the oil reservoir 11 at the bottom. Most of the lubricating oil lubricates the thrust bearing surface 19 through the differential pressure oil supply path, and the remaining lubricating oil lubricates the sliding surface of the Oldham ring 41 and then flows into the suction chamber 38 together with the suction refrigerant gas.

Further, the lubricating oil in the back pressure chamber A23 is decompressed through the injection hole 39 provided in the lap supporting disk 13b of the orbiting scroll 13 and flows into the compression chamber 15, and the lubricating oil in the sucked refrigerant gas together therewith. The oil film seals the compression chamber gap.

The biasing force applied to the orbiting scroll 13 by the lubricating oil pressure in the back pressure chamber A23 is set to be smaller than the gas compressive force acting on the orbiting scroll 13, and the orbiting scroll 13 is always set on the thrust bearing surface 19. Being supported, the orbiting scroll 13 makes an orbiting motion on a plane that is always perpendicular to the main axis of the drive shaft 4. As a result, a smooth slide is made between the orbiting bearing 14 and the orbiting shaft 16 without twisting.

The lubricating oil in the oil sump 11 at the bottom of the motor chamber 37 passes through the oil hole 12, the oil hole A12a, and the oil hole B12b by the pump device 10 provided at the lower portion of the drive shaft 4 to the main bearing 8 in sequence. Each of the slewing bearings 14 is refueled, and then
Return to the motor chamber 37.

For a while after the cold start of the compressor, the pressure in the discharge chamber 32 is lower than the average pressure in the compression chamber 15, and the fixed scroll element 7a is stronger than the force biased toward the orbiting scroll 13. The force acting on the fixed scroll element 7a from the compression chamber 15 side is large. As a result, the fixed scroll element 7a retreats toward the end plate 7b, the axial clearance of the compression chamber 15 increases, the sealing of the compression chamber 15 is released a little, the compression chamber pressure becomes low, and the compression load is reduced.

After that, as the high-pressure side pressure of the refrigeration cycle gradually rises, the pressure of the discharge chamber 32 also rises, and the force for urging the fixed scroll element 7a toward the orbiting scroll 13 also increases, so that the fixed scroll element 7a moves. Move forward toward the orbiting scroll 13. And again the compression chamber 15
The axial clearance of is sealed and efficient compression operation continues.

Further, when instantaneous liquid compression occurs at the initial stage of cold start or during steady operation, the average pressure of the compression chamber 15 becomes high and an overload state occurs, but as in the case described above,
The force acting on the fixed scroll element 7a from the compression chamber 15 side becomes larger than the force that urges the fixed scroll element 7a toward the orbiting scroll 13, and as a result, the fixed scroll element 7a moves to the end plate 7b side. By retreating, the axial clearance of the compression chamber 15 increases, the sealing of the compression chamber 15 is released a little, the pressure of the compression chamber decreases, the compression load is reduced, and abnormal wear and damage of the bearing sliding portion are prevented. . Compression chamber 15
After the pressure is restored to the normal state, the axial gap of the compression chamber 15 is sealed again as described above.

Next, the flow of lubricating oil will be described. A part of the lubricating oil that has flowed into the compressor from the refrigeration cycle piping system together with the suction refrigerant gas through the suction pipe 2 is part of the motor chamber 3.
7, the remaining lubricating oil is discharged to the refrigeration cycle piping system outside the compressor through the suction chamber 38, the compression chamber 35, the discharge chamber 32 and the discharge pipe 33 together with the suction refrigerant gas. The lubricating oil separated from the discharged refrigerant gas by the oil separator in the middle of the refrigeration cycle piping system is supplied to the back pressure chamber A23 via the oil return pipe 34, and the thrust load of the orbiting scroll 13 on which the compression load acts due to the lubricating oil pressure is applied. The friction resistance between the lap support disk 13b and the thrust bearing surface 19 is reduced.

The lubricating oil in the back pressure chamber A is decompressed through the throttle passage 35 and flows into the oil groove 22, lubricates the thrust bearing surface 19, and then flows into the motor chamber 37 through the oil hole 36. This lubricating oil is collected in the bottom oil sump 11.

Further, the lubricating oil in the back pressure chamber A is differentially pressure-fed to the compression chamber 15 through the injection hole 39 provided in the lap support disk 13b to seal the compression chamber gap and fix it to the orbiting scroll 13. Lubricate the sliding surface with the scroll element 7a.

The back pressure chamber A is the first annular seal member 1
8 and the second annular seal member 22, some leakage of lubricating oil lubricates the thrust bearing surface 19 and sliding parts of the main bearing 8.

The circulating oil in the oil sump 11 is supplied to the main bearing 8 and the orbiting bearing 14 through the oil hole A12a and the oil hole B12b by the pump device 10, and then collected in the oil sump 11 again.

As described above, according to the above-described embodiment, the fixed lap support disk 7 is rotationally locked to the end plate 7b forming a part of the fixed scroll 7 and allowed to move only in the axial direction.
The orbiting scroll wrap 13a on the lap support disk 13b forming a part of the orbiting scroll 13 is oscillatably and rotatably meshed with the fixed scroll element 7a including the fixed scroll wrap 7c having a spiral shape. Fixed scroll element 7 forming a spiral compression space
Discharge ports 27a and 27b are provided in the central portion of a and the end plate 7b, a suction chamber 38 is provided outside the fixed scroll wrap 7c, and the compression space is a plurality of compression chambers that continuously move from the suction side toward the discharge side. The orbiting scroll 13 is arranged between the main body frame 5 that supports the drive shaft 4 and the fixed scroll 7, and the wrap support disk 13b is anti-compressed. The chamber side surface is supported by the main body frame 5 so that the fixed scroll element 7a is sandwiched between the end plate 7b and the orbiting scroll 13 and is constantly biased in the direction of the orbiting scroll 13 while maintaining a small axial gap. Biasing means (discharge port 27
By providing the back pressure chamber B28) that communicates with a and 27b, a small axial gap in the compression chamber between the orbiting scroll 13 and the fixed scroll element 7a is ensured during normal operation of the pressure in the compression chamber 15. The compression chamber 15 can be sufficiently sealed. Further, since there is no axial contact between the orbiting scroll 13 and the fixed scroll element 7a, friction loss when the orbiting scroll 13 orbits and the collision between both scrolls is reduced.

As a result, it is possible to provide a compressor which prevents leakage of refrigerant gas during compression and maintains high compression efficiency and has excellent durability with less noise and vibration.

Further, a large amount of liquid refrigerant returns from the refrigeration cycle to the compressor during the initial stage of cold start of the compressor, liquid compression occurs in the compression process, and the pressure in the compression chamber begins to rise abnormally. Even when the axial force acting in the direction of separating the element 7a becomes temporarily excessive,
Since the fixed scroll element 7a retracts toward the end plate 7b, the fixed scroll element 7a widens the axial gap between the fixed scroll element 7a and the orbiting scroll 13 to release the sealing of the compression chamber, and instantaneously reduces the compression chamber pressure to reduce the compressor load. Can be reduced and durability can be increased.

Even when liquid compression does not occur, since the suction pressure is high at the initial stage of starting, the compression ratio of the scroll compressor is constant, so the compression chamber pressure becomes extremely higher than that during normal operation. By properly setting the back pressure biasing force to the fixed scroll element 7a, the fixed scroll element 7a
It is also possible to retreat from the orbiting scroll 13 to reduce the load at the initial stage of activation.

Further, according to the above embodiment, the fixed scroll element 7a is sandwiched between the end plate 7b of the fixed scroll 7 and the orbiting scroll 13 and a small axial gap is maintained. Since the fixed lap support disk 7d of 7a abuts against the spacer 30 for height adjustment sandwiched between the end plate 7b and the body frame 5 to restrict its axial movement, the compression chamber 15 The height of the spacer 30 is adjusted according to the height dimension of the fixed scroll wrap 7c of the fixed scroll element 7a and the orbiting scroll wrap 13a of the orbiting scroll 13 which are extremely important for the sealing of the compression chamber 15 to secure a small axial gap. be able to. As a result, the fixed scroll 7 and the orbiting scroll 1
The cost of 3 and the compression efficiency can be improved.

Further, according to the above-mentioned embodiment, the fixed wrap support disk 7d is constructed so that the outer peripheral portion of the fixed lap support disk 7d abuts against the height adjusting spacer 6 so that the axial movement thereof is restricted. Since the element 7a receives the gas biasing force due to the discharge chamber pressure from the back pressure chamber b28 located at the center thereof, the central portion of the fixed lap support disk 7d is slightly deformed toward the compression chamber 15. As a result, the axial clearance of the compression chamber 15 having a high compression pressure in the vicinity of the discharge port A27a is reduced, and the compression chamber sealing effect is enhanced.

Further, according to the above-mentioned embodiment, the orbiting scroll 13 is arranged between the main body frame 5 supporting the drive shaft 4 and the fixed scroll 7, and the orbiting lap supporting disk 13b is provided.
Is supported by the thrust bearing surface 19 of the body frame 5, and the orbiting wrap support disc 1 is provided on the anti-compression side of the orbiting scroll 13.
An oil separator (not shown) provided with a back pressure chamber A23 formed by 3b and the main body frame 5 and connected to the discharge side of the compressor.
The high pressure lubricating oil is supplied to the back pressure chamber A23 by communicating between the back pressure chamber A23 and the back pressure chamber A23 through the oil return passage through the oil return pipe 34, and the thrust bearing surface 19 is supplied by the pressure through the orbiting scroll 13. It is possible to reduce the compressive load acting on.

Further, according to the above-mentioned embodiment, the orbiting bearing boss 13c provided on the orbiting scroll wrap support disk 13b on the side opposite to the compression chamber is provided with the orbiting bearing 14 for engaging with the drive shaft 4, and the orbiting bearing boss is provided. A first annular seal member 18 mounted in a first annular groove 17 provided on the end surface of 13c and a second annular groove mounted in a second annular groove 20 provided on the thrust bearing surface 19 of the main body frame 5. Since the sealing member 21 and the back pressure chamber A23 form a sealing means, the back pressure chamber A
The sealing property of 23 can be improved. As a result, even when the amount of oil returning from the oil separator to the back pressure chamber A23 is small, there is no blow-through of the refrigerant gas to the sliding portion around the back pressure chamber A23, there is no obstruction to the sliding portion lubrication, and the orbiting scroll. The back pressure effect on 13 can be maintained.

Further, according to the above embodiment, the oil groove 22 is provided on the thrust bearing surface 19 outside the second annular groove 20,
The oil groove 22 and the back pressure chamber A23 are communicated with each other by the throttle passage 35, and the low pressure side motor chamber 37 accommodating the drive shaft 4 and the motor 3 and the oil groove 32 are communicated with each other. A2
The differential pressure oil supply path from 3 to the motor chamber 37 via the thrust bearing surface 19 can be formed by simple means.
This oil supply passage realizes sufficient supply of lubricating oil to the thrust bearing surface 19.

Further, according to the above embodiment, the back pressure chamber A23
Is set so that the orbiting scroll wrap support disk 13b is supported by the thrust bearing surface 19 of the main body frame 5, so that the orbiting scroll 13 orbits on a plane that is always perpendicular to the main axis of the drive shaft 4. You will be exercising. As a result, a smooth turning drive mechanism can be realized without causing one-sided sliding between the turning bearing 14 and the turning shaft 16.

Further, according to the above embodiment, the back pressure chamber A23
And the compression chamber 15 are communicated with each other through the injection hole 39 provided in the lap support disk 13b of the orbiting scroll 13, so that the compression chamber 15 is lubricated in the scroll compressor in which the motor chamber 37 has the same suction pressure. Oil injection can be achieved with a simple structure that saves space, and the compression efficiency is increased by the sealing action of the compression chamber gap by the oil film.

Further, although the refrigerant compressor has been described in the above embodiment, other gas compressors such as oxygen, nitrogen, and helium which use lubricating oil can be expected to have the same effects.

[0078]

As described above, the scroll compressor of the present invention has a spiral wrap and a fixed lap support disk which is rotationally locked to the end plate forming a part of the fixed scroll and is allowed to move only in the axial direction. With respect to the fixed scroll element composed of the fixed scroll wrap, the orbiting scroll wrap on the wrap support disk forming a part of the orbiting scroll is oscillatably rotatably engaged to form a spiral compression space between both scrolls, A discharge port is provided in the center of the fixed scroll element and the end plate, and a suction chamber is provided outside the fixed scroll wrap.
The compression space is divided into a plurality of compression chambers that continuously move from the suction side toward the discharge side to form a scroll compression mechanism that compresses fluid, and the orbiting scroll is provided between the main frame supporting the drive shaft and the fixed scroll. , And its wrap support disc is supported by the body frame on the side of the anti-compression chamber, and the fixed scroll element is sandwiched between the end plate and the orbiting scroll, and it constantly orbits while maintaining a small axial gap. By providing the biasing means so as to be biased in the direction of the scroll, during the normal operation of the pressure of the compression chamber, a minute gap in the compression chamber axial direction between the orbiting scroll and the fixed scroll element is secured, The compression chamber can be sufficiently sealed. Further, since there is no axial contact between the orbiting scroll and the fixed scroll element, friction loss when the orbiting scroll orbits and the collision between the two scrolls is reduced.

As a result, it is possible to provide a compressor which prevents leakage of fluid during compression, maintains high compression efficiency, and has excellent durability with less noise and vibration.

Also, a large amount of liquid fluid returns from the external piping system into the compressor at the initial stage of cold start of the compressor, liquid compression occurs during the compression process, and the pressure in the compression chamber begins to rise abnormally. Even if the axial force acting in the direction of separating the elements becomes temporarily excessive, the fixed scroll element retracts toward the end plate, so the fixed scroll element widens the axial gap with the orbiting scroll and the compression chamber The seal can be released and the pressure in the compression chamber can be instantly reduced to reduce the load on the compressor and improve the durability.

Even when liquid compression does not occur, when the suction pressure is high such as in the initial stage of starting, the compression ratio of the scroll compressor is constant, so the compression chamber pressure becomes extremely higher than that during normal operation. By properly setting the back pressure biasing force to the fixed scroll element, the fixed scroll element can be retracted from the orbiting scroll to reduce the load in the initial stage of startup, so that the input in the initial stage of startup can be reduced. Moreover, since overload can be prevented, durability can be further enhanced.

Further, according to the present invention, the means for holding the fixed scroll element between the end plate of the fixed scroll and the orbiting scroll and maintaining the minute gap in the axial direction is the fixed wrap supporting disk of the fixed scroll element. The fixed scroll wrap of the fixed scroll element, which is extremely important for sealing the compression chamber, is configured by contacting the height adjusting member sandwiched between the end plate and the main body frame and restricting its axial movement. It is possible to adjust the dimension of the height adjusting member according to the height dimension of the orbiting scroll wrap of the orbiting scroll to secure a minute axial gap in the compression chamber. As a result, the costs of the fixed scroll and the orbiting scroll can be reduced. Further, it is possible to prevent the fluid from leaking during compression and improve the compression efficiency.

Further, according to the present invention, since the outer peripheral portion of the fixed lap supporting disc is in contact with the height adjusting member and its axial movement is restricted, the fixed scroll element is positioned at the central portion thereof. Since the fluid urging force due to the discharge chamber pressure is received from the back pressure chamber B, the central portion of the fixed lap support disk is slightly deformed toward the compression chamber. As a result, the axial gap of the compression chamber having a high compression pressure in the vicinity of the discharge port A is reduced and the sealing effect of the compression chamber is enhanced, so that the compression efficiency can be further improved.

Further, according to the present invention, the orbiting scroll wrap on the orbiting wrap supporting disk which is a part of the orbiting scroll is provided for the orbiting fixed scroll wrap which is formed on one surface of the end plate which is a part of the fixed scroll. It oscillates and rotatably meshes to form a spiral compression space between both scrolls, and a discharge port is provided in the center of the fixed scroll wrap.
A suction chamber is provided outside the fixed scroll wrap, and the compression space is divided into a plurality of compression chambers that continuously move from the suction side toward the discharge side to form a scroll compression mechanism that compresses fluid, and the orbiting scroll is driven. It is arranged between the main body frame supporting the shaft and the fixed scroll, and the orbiting wrap supporting disc is supported by the thrust bearing surface of the main body frame, and the orbiting wrap supporting disc and the body frame are provided on the anti-compression side of the orbiting scroll. By providing the formed back pressure chamber and connecting the oil separator connected to the discharge side of the compressor and the back pressure chamber with the oil return passage, the high pressure lubricating oil is supplied to the back pressure chamber A, It is possible to reduce the compressive load acting on the thrust bearing surface via the orbiting scroll by the pressure, and to provide a compressor with less input loss.

Further, according to the present invention, the orbiting bearing which engages with the drive shaft is provided on the protrusion on the side opposite to the compression chamber provided on the orbiting scroll wrap supporting disc, and the first bearing is provided on the end face of the protrusion. The first annular seal member installed in the annular groove and the second annular seal member installed in the second annular groove provided on the thrust bearing surface of the main body frame constitute the back pressure chamber sealing means. The tightness of the chamber A can be improved. As a result, even when the amount of oil returning from the oil separator to the back pressure chamber A is small, there is no fluid leakage to the sliding portion around the back pressure chamber A, and the lubrication of the sliding portion is not hindered. It is possible to provide a compressor that can maintain the back pressure action and that has less wear on the sliding portion and has excellent durability.

According to the present invention, the thrust bearing outside the second annular groove is provided with an oil groove, the oil groove and the back pressure chamber are communicated with each other by a throttle passage, and the low pressure housing the drive shaft and the electric motor. Since the electric motor chamber on the side is communicated with the oil groove, the back pressure chamber A
It is possible to form the differential pressure oil supply path from the to the motor chamber via the thrust bearing surface by a simple means. Since this oil supply passage can supply sufficient lubricating oil to the thrust bearing surface,
A compressor with excellent durability can be realized at low cost.

Further, according to the present invention, the pressure of the back pressure chamber is set so that the orbiting scroll wrap supporting disc is supported by the thrust bearing surface of the main body frame, so that the orbiting scroll is always perpendicular to the main shaft of the drive shaft. It makes a turning motion on a flat plane. Therefore, it is possible to realize a smooth turning drive mechanism without causing one-sided sliding between the turning bearing and the turning shaft, so that wear of the turning bearing portion is reduced.
By keeping the radial clearance of the compression chamber to a minimum,
It is possible to improve the reliability by preventing a decrease in compression efficiency and an increase in input.

Further, according to the present invention, the back pressure chamber and the compression chamber are communicated with each other by the throttle passage provided in the orbiting scroll, so that in the scroll compressor in which the motor chamber has a suction pressure equal to that of the compression chamber. The lubricating oil injection can be realized with a space-saving simple structure, and the compression efficiency can be improved by the sealing action of the compression chamber gap by the oil film.

[Brief description of drawings]

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

[Figure 2] Enlarged vertical cross-sectional view of the main part

FIG. 3 is a vertical sectional view of a conventional scroll compressor.

FIG. 4 is an enlarged vertical sectional view of the same main part.

FIG. 5 is a vertical sectional view of another conventional scroll compressor.

[Explanation of symbols]

 3 Motor 4 Drive Shaft 5 Body Frame 6 Spacer 7 Fixed Scroll 7a Fixed Scroll Element 7b End Plate 7c Fixed Scroll Wrap 7d Fixed Wrap Support Disk 13 Orbiting Scroll 13a Orbiting Scroll Wrap 13b Wrap Support Disk 13c Orbiting Bearing Boss 14 Orbiting Bearing 15 Compression Chamber 17 1st annular groove 18 1st annular seal member 19 Thrust bearing surface 20 2nd annular groove 21 2nd annular seal member 22 Oil groove 23 Back pressure chamber A 27a, 27b Discharge port 28 Back pressure chamber B 30 Spacer 32 Oil Groove 34 Oil Return Pipe 35 Throttle Passage 37 Motor Chamber 38 Suction Chamber 39 Injection Hole

Claims (8)

[Claims] 1. A fixed scroll element composed of a fixed wrap support disk which is rotationally locked to a mirror plate forming a part of the fixed scroll and is allowed to move only in an axial direction, and a spiral fixed scroll wrap, The orbiting scroll wrap on the wrap support disk forming a part of the orbiting scroll is rotatably and rotatably meshed with each other to form a spiral compression space between both scrolls, and is discharged to the central portion of the fixed scroll element and the end plate. A port is provided, and a suction chamber is provided outside the fixed scroll wrap, and the compression space is divided into a plurality of compression chambers that continuously transition from the suction side to the discharge side to form a scroll compression mechanism that compresses fluid. The orbiting scroll is disposed between the main body frame that supports a drive shaft and the fixed scroll, and the wrap support disk is located on the side opposite to the compression chamber. A biasing means supported by the main body frame so that the fixed scroll element is sandwiched between the end plate and the orbiting scroll and always biased in the orbiting scroll direction while maintaining a small axial gap. A scroll compressor provided with. 2. A means for sandwiching a fixed scroll element between an end plate of a fixed scroll and an orbiting scroll and maintaining a minute gap in the axial direction is a fixed wrap supporting disk of the fixed scroll element and the end plate. 2. The scroll compressor according to claim 1, wherein the scroll compressor is in contact with a height adjusting member sandwiched between the main body frame and the axial movement thereof and is restricted. 3. The scroll compressor according to claim 2, wherein an outer peripheral portion of the fixed lap supporting disk abuts on the height adjusting member and its axial movement is restricted. 4. An orbiting scroll wrap on a orbiting wrap supporting disk forming a part of an orbiting scroll is oscillatably rotatable with respect to a spiral scrolling scroll wrap formed on one surface of an end plate forming a part of the fixed scroll. To form a spiral compression space between the two scrolls, a discharge port is provided at the center of the fixed scroll wrap, and a suction chamber is provided outside the fixed scroll wrap. A scroll compression mechanism is formed that is partitioned into a plurality of compression chambers that continuously move toward the discharge side to compress the fluid, and the orbiting scroll is disposed between the main body frame that supports the drive shaft and the fixed scroll. The orbiting lap supporting disc is supported on the thrust bearing surface of the main body frame, and the orbiting wrap supporting disc is provided on the anti-compression side of the orbiting scroll. A scroll compressor provided with a back pressure chamber formed by the main body frame and an oil separator connected to the discharge side of the compressor and the back pressure chamber by an oil return passage. 5. A swivel bearing that engages with a drive shaft is provided on the projection on the side opposite to the compression chamber provided on the swivel scroll wrap support disk, and the swivel bearing is attached to the first annular groove provided on the side surface of the projection. 5. The scroll compressor according to claim 4, wherein the first annular seal member and the second annular seal member mounted in the second annular groove provided on the thrust bearing surface of the main body frame constitute a sealing means for the back pressure chamber. 6. A thrust bearing outside the second annular groove is provided with an oil groove, the oil groove and the back pressure chamber are communicated with each other by a throttle passage, and a low pressure side electric motor chamber accommodating a drive shaft and an electric motor is provided. The scroll compressor according to claim 4, wherein the oil groove is communicated with the oil groove. 7. The scroll compressor according to claim 4, wherein the pressure of the back pressure chamber is set so that the orbiting scroll wrap supporting disk is supported by the thrust bearing surface of the main body frame. 8. The scroll compressor according to claim 6, wherein the back pressure chamber and the compression chamber are communicated with each other by a throttle passage provided in the orbiting scroll.