JPS6014917B2 - positive displacement fluid compression device - Google Patents

Description

[Detailed Description of the Invention] The present invention involves meshing a pair of spiral bodies at different angles, applying relative circular motion (only orbital motion), and moving the sealed space formed between the spiral bodies toward the center. The present invention relates to a positive displacement fluid compression device, a so-called scroll compressor, which discharges compressed fluid from the center by reducing its volume while moving.

The principle of such a scroll compressor itself has been known for a long time.

Referring to FIG. 1, when two scroll bodies 1 and 2 are disposed at different angles and intermeshed with each other, as shown in the figure, there is a gap between the two spiral bodies from the contact part to the contact part. A confined space 3 is formed that spans the area.

Now, move one scroll body 1 to the other scroll body 2 so that the center ○ of one scroll body 1 revolves around the center ○ of the other scroll body 2 with a radius ○−〇. When it is moved while prohibiting rotation, the volume of the limited space 3 gradually decreases. From the situation in Figure 1a, Figures 1b and 1 show that the revolution angle of the scroll body 2 is 90o.
With reference to FIG. 1c showing 800 and FIG. 1d showing 270o, it will be seen that the volume of space 3 (dotted area) is gradually reduced.

In Figure 1a, which has been further rotated by 360 degrees, both spaces have moved to the center and connected to each other, and in Figure 1B, which has been further rotated by 90 degrees,
As shown in Figures c and d, the space narrows, and as shown in Figure 1 d.
Then it becomes zero. During this time, the outer space that began to open in Figure 1b moves from Figures 1c and d to Figure 1a, creating a sealed space that takes in new fluid. Therefore, these scroll bodies 1 and 2
If sealed disks are provided at both ends of the axis in all directions, and a discharge hole as shown in the figure is provided in the center of one disk,
The fluid taken in on the outside in the opposite direction is compressed and discharged from the discharge hole 4.

By the way, the scroll compressor based on this principle is
Although it has advantages over piston-type compressors, such as fewer parts and less wear, it has not been put into practical use mainly due to the difficulty of sealing between both scroll bodies.

For example, a crankshaft may be used to make one scroll revolve around the center of the other scroll, but in that case, the rotation radius of the crankshaft is smaller than the required orbital radius of the scroll. If the rotation radius of the crankshaft is larger than the required orbital radius of the scroll, a gap will be created between the spiral bodies of both the scroll bodies, and vice versa Furthermore, even if they were combined, the spiral bodies of both scroll bodies would come into strong contact with each other, and the large frictional force at that time would make orbital motion virtually impossible.

If the rotation radius of the crankshaft and the required orbital radius of the scroll body are matched, the above-mentioned problem can be solved to some extent, but this is impossible in terms of manufacturing. Further, if a manufacturing error occurs in the spiral body or if it becomes loose due to external force applied during operation, there is a risk of the above-mentioned sealing failure or inability to move.

Furthermore, when operating under high discharge pressure, the force that tends to separate the swirling wall forming the limited space between both scroll bodies increases, so a stronger sealing force is required.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a scroll compressor in which the limited space formed between both scrolls can be easily and reliably sealed, and the sealing force can be increased as the discharge pressure increases.

The present invention provides a first scroll member having a spiral body fixed on one surface of a plate, and a second scroll member having a spiral body fixed on one surface of the plate in the same machine, by adjusting the angle of both spiral bodies. The first scroll member is moved relative to the second scroll member so as to move on a circular orbit while being shifted and interlocked with each other, and a closed space is formed between both spiral members while fluid is flowing. A positive displacement fluid compression device that takes in the space and moves the space toward the center as the first scroll section moves, and performs a unidirectional continuous flow compression action with a reduction in volume. A cylindrical protrusion is provided on the opposite surface of the plate of the first scroll member, and a high pressure introduction hole passing through the plate is provided at the inner bottom of the cylindrical protrusion. On the main shaft rotatably supported on the shaft D, which coincides with the center of revolution of the cylindrical projection when the scroll part is moved in a circular orbit with the maximum radius,
A crank pin is provided that revolves around the groin center of the main shaft with a radius smaller than the revolution radius of the cylindrical protrusion, a cylindrical sleeve is fitted to the crank pin with a gap, and a seal body is provided in the gap. A sealed semi-cylindrical space is provided in the gap on the opposite side of the rotation center of the crank pin; An open high-pressure passage is provided on the end face of the shaft, and the sleeve is iron-fitted into the cylindrical protrusion via a radial bearing to allow the high-pressure passage to pass through the high-pressure introduction hole, thereby compressing the space. This positive displacement fluid compression device is characterized in that fluid pressure acts in a direction that increases the revolution radius of the first scroll.

FIG. 2 is a central cross-sectional view showing the structure of an embodiment of the present invention. Referring to FIG. In this example, it is integrated with the rear end plate.) The fluid suction row 4 and the fluid discharge port 15 formed in the rear end plate 12 form a sealed chamber that communicates with the outside. A main shaft 17 extends through the front end plate 11 and is rotatably supported thereon via a radial needle bearing 16.
is installed.

The front end plate 11 surrounds the main shaft 17.
A shaft seal mechanism 19 is installed around the main shaft in the cylinder body 18 that protrudes from the front, and a pulley 20 is supported by bearings on the outside of the cylinder body.
The rotating force from an external drive source (for example, a motor) is transmitted to the main shaft 17 via the belt. A rotor 21 is fixed to the inner end of the main shaft 17, and this rotor is attached to the front end plate 11.
Thrust needle bearing 2 installed concentrically with the main shaft on the inner surface of
It is supported by 2.

A shaft (crank pin) 23 is provided on the opposite side of the rotor 21 from the front end plate 11, protruding from the rotor and eccentric from the main shaft. 24, 25
are a pair of scroll members, each of which has a single disc 24
1,251, spiral bodies 242, 252 are fixed to one side.

The curves of these spiral bodies 242, 252 may be not only circular expansion lines but also line segment expansion lines or polygonal expansion lines. One scroll member 24 further has a cylindrical protrusion (hereinafter abbreviated as "r protrusion") 243 provided with an axial round hole on the opposite surface of the disk 241.

Further, the other scroll member 25 further includes the spiral body 2
52, there is a through hole 253 corresponding to the discharge hole shown by symbol 4 in FIG. It has an annular protrusion 254 provided at. The scroll member 25 has a protrusion 254 inserted into the annular protrusion 121 provided on the inner surface of the end plate 12 so as to surround the fluid discharge port 15, and a protrusion 254 is partially inserted into the circumferential green part of the disc 251. The protrusion 131 protruding from the inner surface of the cylindrical side wall 13 is engaged with the provided notch to prevent rotation when the housing is assembled into the housing.

Note that an annular elastic body 30 made of rubber or the like is disposed between the tip of the protrusion 254 and the inner surface of the chain end plate 12. This annular elastic body 3 is sealed between the protrusion 254 and the chain end plate 12, and the annular protrusion 254 is sealed.
The inside is a discharge chamber 31 that communicates with the fluid discharge chamber 15 and the through hole 253 of the scroll member 25. The annular elastic body 30 also plays the role of elastically supporting the scroll section 25 in the direction of the ball. On the other hand, scroll club village 2
4, as described using FIG. 1, the spiral bodies 241 and 251 are overlapped with the scroll member 25 in a state in which they are engaged with each other at different angles.

In such a combination of both scroll members 24 and 26, as explained using FIG.
4 revolves in a predetermined direction with a radius as large as possible while prohibiting rotation, a limited space is formed between both spiral bodies 241 and 251, and the limited space is moved toward the center while decreasing its volume. That will happen. Here, the revolution radius of the scroll member 24 that performs such an action is called the required revolution radius. When the scroll part village 24 is made to revolve in this manner, the protrusion 243 provided thereon will revolve around the single touch with the same radius as the required revolution radius. Further, the protrusion 243 of the scroll member 24
A flange body 27 is provided at the protruding end of the scroll member 24, and the flange body 27 is provided with a flange surface that extends in the direction of the scroll. Thrust needle bearing 2 with D'
It is supported by 8.

Now, during this revolution movement of the scroll member 24, in order to prevent the scroll member 24 from rotating, the scroll member 24
An anti-rotation mechanism 29 installed on the inner surface of the cylindrical wall 13 of the housing 10 is located between the disk 241 of No. 4 and the flange body 27.
is provided.

Figure 2 and Figure 3 showing a cross section along line m-m in Figure 2.
An example of this anti-rotation mechanism will be explained with reference to the drawings. Referring to both figures, the flange body 27 includes a rectangular cylindrical portion 271 having a rectangular outer shape, which extends over the protrusion 243 and is keyed to the protrusion 243 to prevent mutual rotation.

Here, the length of the flange body in all directions including the rectangular tube portion is greater than or equal to the length of the protrusion 243 of the scroll member 24 in the ball direction.
As a result, the thrust load applied to the scroll member 24 is supported by the rotor 21 via the thrust needle bearing 28. A sliding body 291 having a square outer shape and a square hole is installed on the square tube part 271.

As shown in FIG. 3, the square hole of the sliding body 291 is
The pair of opposing sides has the same dimensions as the pair of sides of the square tube part 271, and the remaining pair of sides is longer than the other pair of sides by more than twice the eccentricity of the crank pin 23, so that The rectangular tube portion 271 and the sliding body 291 are capable of sliding relative to each other in one direction. A ring member 292 is disposed around the moving body, and the sliding body 291 is joined to the ring member, and the ring member is installed on the inner surface of the cylindrical side wall of the housing by a key connection (indicated by 293) so as to be prevented from rotating.

The hole in the center of the ring member is a square hole, and has a pair of sides that have the same dimensions as a pair of opposing sides of the outer shape of the sliding body, and is longer than the remaining pair of sides by at least twice the eccentricity of the crank pin 23. It has a rectangular shape consisting of a pair of sides, and the sliding body 29
1 is guided so that it slides in a direction perpendicular to the sliding direction with respect to the square tube portion 271. Thus, although the rectangular tube portion 271 is movable in two mutually orthogonal directions, it is prohibited from rotating, and is therefore allowed to move on a circular orbit as a combination of movements in two orthogonal directions.

Therefore, due to the eccentric rotational movement of the crank pin 23 accompanying the rotation of the main shaft 17, the rectangular tube portion 271 and therefore the scroll member 24 do not rotate but move (revolution) on a circular orbit. The navigating member 292 does not need to have a square hole for ironing the navigating body, but has a hole that allows the flange body to pass through.
Further, a recess for receiving the sliding member may be formed on one end surface, and a side wall of the recess may guide the sliding movement of the sliding member.

In this case, the thickness of the emotional body is naturally reduced.
By the way, the axis of the main shaft 17 is made to coincide with the center of revolution of the protrusion 243 when the scroll member 24 is revolved with a required revolution radius, and
The crank radius is made slightly smaller than the required radius of revolution of the scroll member 24, and a cylindrical sleeve 32 having an inner diameter slightly larger than the diameter of the crank pin 23 is mated thereto. As a result, a gap remains between the crank pin 23 and the cylindrical sleeve 32. At this time, a seal ring 33 as shown in FIG. 4 is fitted and held on the circumferential surface of the crank pin 23. This seal ring 33 is arranged between two rings 331 which are spaced apart from each other and which face each other in the vertical direction.
32 are bridged and fixed respectively. Therefore,
The gap between the crank pin 23 and the cylindrical sleeve 32 is divided into two in the circumferential direction by a seal ring 33.
Semi-cylindrical spaces 34 and 35 are formed in the outer and inner parts of the crank pin 23, respectively, when viewed from the main shaft 17.
However, in the figure, the chest ○ of the cylindrical tube 32 is tilted radially outward with respect to the axis 0 of the crank pin 23, so the inner semi-cylindrical space 35 is not clearly defined. Not shown. Note that a key 36 is inserted between the crank pin 23 and the cylindrical sleeve 32 in order to prevent mutual rotational deviation. Also crank pin 2
3, a recess 231 is formed in the end surface of the shaft, and a sealing plate 37 having a through hole 371 in the center is inserted into the entrance of the recess 231.

At this time, the seal plate 37 is engaged with the shoulder 232 of the recess 231 via the seal ring 38, thereby forming a high pressure introduction chamber 39 within the recess 231. The crank pin 23 is further provided with a vent hole 233 for transporting the high pressure introduction chamber 39 into the outer semi-cylindrical space 34 . Further, the cylindrical sleeve 32 is provided with a ventilation hole 321 that is open at one end in the inner semi-cylindrical space 35 and closed at the other end in the axial end face. In this way, the cylindrical sleeve 3 is attached to the crank pin 23.
2 is further fitted into the round hole of the protrusion 243 of the scroll member 24 via the radial needle bearing 26, so that the scroll member 24 is slightly mounted on the crank pin 23. It is supported by bearings with a slight play.

Further, in this assembled state, the disc 241 of the scroll member 24 has a high pressure introduction hole 244 communicating with the through hole 371 of the seal plate 37.

In the above structure, if the main shaft 17 is rotated via the pulley 20 by an external drive source, the crank pin 23
Due to the offset zero movement, the scroll part 24 is prevented from rotating on its own axis, and also moves on a circular orbit having a required revolution radius due to the action of the centrifugal force of each part.

At this time, the movement G of the scroll member 24 relative to the scroll member 25 is similar to that shown in FIG.
It moves to the center while being gradually compressed, is discharged from the through hole 253 into the discharge chamber 31, is discharged from the discharge port 15, circulates through the cooling system, for example, and returns into the housing 10 from the suction port 14. Also at this time, the scroll member 24,
The high pressure fluid that has moved to the center of 25 passes through the high pressure introduction hole 244 and the through hole 371 of the seal plate 37 and enters the high pressure introduction chamber 39.
and further flows into the outer semi-cylindrical space 34 through the ventilation hole 233, so this space 34 is completely expanded, which is equivalent to increasing the crank radius of the crank pin 23, and eventually the crank pin 23 and cylindrical sleeve 3
2 are practically unified.

At this time, the vent hole 321 serves to make the pressure in the inner semi-cylindrical space 35 the same as the suction pressure. For this reason, a force is always applied to the scroll member 24 to increase its radius of motion, so that the spiral body 242 is strongly pressed against the spiral body 252 of the other scroll member 25, and sealing is performed in the radial direction. Moreover, as the operating speed is high and the pressure of the fluid at the center of the scroll members 24, 25 becomes high, a strong sealing force can be obtained. Furthermore, even if the spiral bodies 242 and 252 are distorted or eccentric, the above-mentioned sealing force can be reliably obtained, and the crank radius will vary within the range of the set clearance of the above-mentioned outer semi-cylindrical space 34. By absorbing such errors,
Always follow with the required crank radius.

Note that the radial force due to the high pressure in the outer semi-cylindrical space 34 is larger than the radial force that attempts to separate the spiral bodies 242 and 252 due to the pressure of the fluid trapped between the spiral bodies 242 and 252. The area on which high pressure acts in the outer semi-cylindrical space 34 is set so that the spiral body 242 of the scroll member 24 is always pressed in the radial direction toward the spiral body 252 of the other scroll member 25.

According to the above-described structure, the scroll member 25 is urged in the axial direction by the elastic force of the annular elastic body 30, so that it is pressed against the scroll member 24.

Therefore, a sealing force is provided between the disc 251 of the scroll member 25 and the end of the spiral body 242 of the scroll member 24 and between the disc 241 of the scroll member 24 and the end of the spiral body 252 of the scroll member 25. This sealing force is
The gas pressure in the discharge chamber 31 is increased by acting on the scroll member 25 in the axial direction. On the other hand, the elastic force of the elastic annular body and the gas pressure in the discharge chamber cause the flange body 27 to
This also acts as a thrust force that presses against the roller 21, and this is supported on the inner surface of the front end plate 11 via thrust needle bearings 28 and 22 in sequence. As a result,
Shakiness of each part is eliminated, and therefore vibration and abnormal wear are prevented. In addition, since the rotor is thrust-supported near the circumference of the rotor 21 fixed to the main shaft 17,
The main shaft 17 is firmly fixed without vibration by only one radial bearing, which is the needle bearing 16. Furthermore, in the above structure, when the front end plate of the housing is removed, the scroll members 25 and 24, the rotation prevention mechanism 29, and the flange body 27 are separated from the elastic annular body 30.
, needle bearings 26, 28, crank pin 23, rotor 21, and main shaft 17, are stacked in the housing in this order, and the front end plate 11 is stacked on top of them, and the bolts 4 are stacked.
It is assembled by fixing with 0 etc. The assembly order may be reversed. In this case, it is better that the rear end plate is removable. Incidentally, although not shown in the drawings, it is preferable that a counter hole or a counterweight be formed or added to the rotor 21 to maintain dynamic balance. As explained above using the embodiments, according to the present invention, even if the dimensions and shapes of both scroll members and the eccentricity of the crank pin are slightly different from the designed ones, a reliable sealing effect can be obtained. It is easy to manufacture because it does not interfere with operation, and the sealing force increases as the discharge pressure increases, so it prevents increased wear and energy loss caused by constantly applying more sealing force than necessary. A scroll type compressor that can reduce the amount of air is obtained.

[Brief explanation of drawings]

Figures 1 a to d are diagrams for explaining the compression principle of the scroll compressor according to the present invention, a to d are diagrams showing states at different angular positions, and Figure 2 is an embodiment of the present invention. FIG. 3 is a sectional view taken along line mm in FIG. 2, and FIG. 4 is a perspective view of the seal ring. 1, 2... Spiral body, 3... Sealed space, 4... Discharge hole, 10... Housing, 11
...Front end plate, 12...Rear end plate, 13...Cylindrical side wall, 14...Fluid inlet, 15...Fluid outlet, 16, 26.
... Radial needle bearing, 17 ... Main shaft, 21 ... Rotor, 22, 28 ... Thrust needle bearing, 23 ... Crank pin, 2
4, 25...Scroll member, 29...
・Rotation prevention mechanism, 30...Elastic annular body, 31.
...Discharge chamber, 32...Cylindrical sleeve, 33
... Seal ring, 34, 35 ... Semi-cylindrical space, 37 ... Seal plate, 39 ... High pressure introduction chamber, 241, 251 ... Yen Board, 242,2
52...Uzumaki body. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. A first scroll member having a spiral body fixed on one side of the plate and a second scroll member having a spiral body similarly fixed on one side of the plate are mutually connected by shifting the angles of both spiral bodies. The first scroll member is moved relative to the second scroll member so as to move in a circular orbit, and fluid is drawn in while forming a closed space between the two spiral bodies. In the positive displacement fluid compression device, the space is moved toward the center with the movement of the first scroll member, and the volume is decreased to perform a unidirectional continuous flow compression action. A cylindrical protrusion is provided on the opposite surface of the plate material of the member, and a high pressure introduction hole passing through the plate is provided at the inner bottom of the cylindrical protrusion, while the first scroll member has a maximum radius. The main shaft is rotatably supported on an axis that coincides with the center of revolution of the cylindrical protrusion when the cylindrical protrusion moves in a circular orbit. A crank pin that revolves around the axis is provided, and a cylindrical sleeve is fitted to the crank pin with a gap, and a seal body is inserted into the gap to connect the rotation center of the crank pin to the center of rotation of the crank pin. is provided with a sealed semi-cylindrical space on the opposite side, and the crank pin is provided with a high-pressure passage having one end opened in the semi-cylindrical space and the other end opened in the end face of the crank pin shaft. The sleeve is fitted into the protrusion via a radial bearing to communicate the high pressure passage with the high pressure introduction hole, whereby the compressed fluid pressure in the space acts in a direction to increase the revolution radius of the first scroll. A positive displacement fluid compression device characterized by: