JPH084672A - Scroll type fluid machinery - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] To obtain a scroll fluid machine that can stabilize the operation and increase the scroll tooth length and easily increase the capacity of the fluid machine. [Structure] An orbiting scroll eccentric shaft and a pin crank 12 are formed at a central boss portion 4a by meshing of a scroll provided with a boss portion 4a on an orbiting scroll 4, so that the pin crank 12 is further supported on the left end. And a scroll fluid machine configured as. Oil-free scroll type fluid machinery can be obtained immediately by scroll engagement, clearance, and grease bearing type bearing. By using the pink rank 12 in various ways, the scroll compression unit can be expanded into two blocks in parallel or in two stages.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll fluid machine.

[0002]

2. Description of the Related Art A scroll fluid machine is a left-handed machine of the same shape,
Or, a pair of scroll members provided with a thickness with right-handed scroll teeth are engaged with each other with a phase of 180 °,
One is fixed and the other is not rotated with respect to the fixed side.
It is generally known that the space gradually decreases in volume toward the center and is compressed. That is, with the semicircular arc as a reference, if the minimum circular arc is the minimum radius R in the upper half of the centerline, the minimum circular arc R ₂ of the lower half is 2R, and
The upper half of the second arc R ₃ has a radius of 3R, and the lower half of the second arc R ₄ is a continuous arc with a radius of 4R, as shown in FIG. 9. Therefore, due to the meshing of the scrolls, the compression process is configured to operate up to the center of the scroll teeth. Therefore, a bearing for supporting the orbiting scroll is provided outside the orbiting scroll disk,
Further, the pin crank mechanism for ensuring the turning motion is usually mounted on the outer peripheral portion on the outer side of the disk.

A known example of a scroll tooth structure which has been conventionally used is shown in Japanese Patent Application No. 64-1674.

[0004]

The conventional scroll fluid machine is constructed on the basis of the above technical basis.
First, considering the scroll tooth profile, to the center,
Although it has a scroll tooth shape capable of achieving a compression ratio, when viewed as a compressor, the size of the discharge hole at the center corresponding to a discharge pressure of 7 kgf / cm ² is configured to be relatively large from the compression ratio, and the compression at the center is Most of the time, it is communicated with the discharge hole before it is added. That is, the mechanism of the central part is not effectively used. Reference numeral 3a in FIG. 8 indicates this discharge hole. Moreover, since the scroll teeth mesh with the center part, the bearing that holds rotation and orbit is located outside the orbiting scroll disk and in the direction of the drive shaft end, and because one-sided bearing support is provided, the orbiting accuracy cannot be obtained. There are drawbacks. Therefore, it has the disadvantage that the scroll tooth length cannot be increased.

On the other hand, since the bearing cannot be mounted at an efficient position for receiving a radial load with respect to the scroll tooth length for compression work, and the bearing is provided outside the scroll disk, the bearing has a scroll tooth. Acts as a moment equivalent to the applied radial load and the distance to the bearing mounting position,
It is necessary to consider the load capacity beyond necessity. This bearing position also has the disadvantage of requiring a space in the axial direction.

In recent years, a method using a pin crank is often used in order to make the orbiting motion without rotating the scroll, but this pin crank is mounted on the outer peripheral portion of the scroll disk due to the construction of the fluid machine. However, if only the outer peripheral portion is attached, the mounting is unstable due to expansion of the orbiting scroll disc portion, stacking of mounting dimension tolerances of the bearing, the disc, the housing, and the like. In order to solve this series of problems, a shock absorbing structure is incorporated into the pin crank bearing, and this is rather the cause of the orbiting scroll swinging and swinging. These configurations are shown in FIGS. 7 and 8.

[0007]

Means for Solving the Problems According to the present invention for solving the above problems, the orbiting scroll has a structure in which a bearing and a boss into which a shaft can be fitted are provided in a central portion, and the compression chamber is reduced by the orbiting motion. For the purpose of configuration, the tip of the tooth near the center of the fixed scroll has a different tooth shape from the orbiting scroll, and has a structure capable of continuous sealing.

A shaft and a bearing that are eccentric to the drive shaft are fitted into the orbiting scroll boss portion, and the tip of the shaft and the bearing is a bag-shaped wall. On the other hand, the tip of the boss is fitted with a pin crank and a bearing which are eccentric from the shaft center into which the crank-shaped drive shaft is fitted and have the same amount of eccentricity as the eccentric drive shaft, and mainly serve to prevent rotation. The other end of the pink rank has a structure in which the bearing of the frame holds the turning motion. In order to prevent rotation of the orbiting scroll during the orbiting operation, a pin crank-shaped eccentric shaft is incorporated on the side surface of the orbiting scroll and supported by a bearing lid via a bearing. In addition, holding the orbiting scroll boss portion by the frame bearing portion of the pin crank simultaneously supports the orbiting scroll on both sides.

[0009]

Operation: First, do not make the scroll teeth the same shape on the right and left,
Although the boss portion is formed in the center of the orbiting scroll, the size of the discharge hole with respect to the compression ratio is shown in FIG. 8. There is no big difference compared with the conventional practical discharge hole of the scroll tooth, and it is a major drawback in practical use. I won't. The engagement between the fixed scroll and the orbiting scroll is characterized by the seal structure of the fixed scroll so that a required compression ratio can be ensured, which will be described later in the embodiment.
In the orbiting scroll that constitutes the boss part, the eccentric shaft from the drive shaft is fitted in the boss part together with the bearing, so the radial load applied to the scroll teeth is directly supported by the load, so the load is not wasted and the drive shaft is Can be made short. Next, as shown in FIG. 1, the left end of the boss portion is fitted with a pin crank whose S dimension is eccentric with the eccentric shaft, and serves as a base point of the turning motion in the bearing portion of the frame. Attaching the pin crank at this position is not related to the thermal expansion in the radial direction due to the operation, and is the same mechanism as supporting the orbiting scroll at the center to support the bearings on both sides. Therefore, the biggest drawback of conventional scrolls is that the scroll tooth width due to cantilever cannot be increased, and the scroll tooth width can be made sufficiently large, so that the discharge capacity of the scroll fluid machine is planned to be doubled or tripled. What you can do has become easier. As a method for preventing the swing of the orbiting scroll, an eccentric shaft having the same eccentricity as the pin crank is attached to the side surface of the orbiting scroll to support the pin crank at two or more points.
It prevents rotation and realizes a swinging motion without shake. Also, if the pin crank is attached only to the outer circumference of the conventional orbiting scroll disk, the force that tries to rotate the orbiting scroll that occurs on the eccentric drive shaft of the orbiting scroll acts as a large moment on the pin crank. However, if the pin crank is attached mainly to the end face of the boss portion as in the present invention, the moment is small and the shaft diameter and the bearing can be small.

The pin crank is attached to the end surface of the boss portion, as shown in FIG. 2, when the scroll compression portions are arranged in two blocks in parallel, the pin crank can be easily constructed by a gable L-shaped pin crank. Since the functions of compression and discharge are alternately performed, the turning motion is perfectly balanced, the balance weight is unnecessary, and the structure is suitable for high-speed operation. FIG. 3 shows a two-stage type in which this configuration is connected in series.

[0011]

Embodiments of the present invention will be described with reference to FIGS. 1, 5 and 6. Reference numeral 1 is a frame in which a drive eccentric shaft and a bearing for holding the base point of the eccentrically mounted pin crank are fitted.
Reference numeral 2 is a bearing lid, which supports the drive eccentric shaft 5 with bearings 9 and 10. 5a is a drive shaft. A fixed scroll 3 is fitted and fixed in one frame. 4 is an orbiting scroll, 4a is an orbiting scroll boss portion, 4b is a wall of the boss portion, 6 is a suction port, 7
Is a discharge port, and 8 is a boss bearing, which is rotatably attached. 11
Is a pin crank base point bearing, 12 is a pin crank, and 13 is a pin crank bearing which is fitted into the orbiting scroll boss portion 4a while maintaining the S eccentricity of the pin crank. Reference numeral 14 is a balance weight, and 15 is a pin crank-shaped rotation preventing eccentric shaft having the same amount of eccentricity as the drive eccentric shaft, which is held by the orbiting scroll and the bearing lid.

The structure of the scroll teeth of the present invention will be described with reference to FIGS. 4. For orbiting scroll, A-A ', Y-
Based on a and t at the Y'base line, R ₁ =
a + t / 2, R _1a = R ₁ + K + t, R ₂ = R _1a + K
+ T, R ₃ = R ₂ + K + t, and the arc scroll has a boss portion at the center of the scroll. Also, the fixed scroll is composed of BB 'and YY' base lines, and the inner tip of the scroll has R ₁ = a + t / 2, R ₄ = R.
_1a- t forms a seal line with the orbiting scroll, and R
_{1a = R 1 + K + t} , R 2 = R 1a + K + t, R 3 = R
₂ + K + t has the same tooth profile as the orbiting scroll. a is a basic dimension determined by the bearing fitted into the drive eccentric shaft or the boss portion, and is arbitrarily determined. K represents the amount of eccentricity of the drive eccentric shaft, and t represents the thickness of the scroll teeth. l indicates the orbital diameter of the orbiting scroll, and l = 2K. The meshing of the scroll in FIG. 5 represents the time when the suction is completed in the enclosed space of 17a and 17b by the upper fulcrum of the orbiting diameter, that is, the orbiting and fixed scroll teeth.

Next, the meshing operation of the scroll will be described with reference to FIG. It shows the meshing at 0 ° in the upper left, and when the orbiting scroll is turned in the direction of the arrow immediately before the completion of inhalation, 17
The fluid is enclosed in a and 17b. Reference numeral 18 denotes the enclosed compressed fluid before being swirled, and the compressed fluid is supplied to the use destination from the fixed scroll discharge port 3a. The lower left, 90 ° position is 17a in the meshing diagram where the orbiting scroll is rotated 90 °,
It is shown that the fluid-filled space of 17b is compressed and enters the discharge stroke from the fixed scroll discharge port 3a. At the lower right, 180 ° position, the volume of the fluid in the enclosed spaces 17a and 17b is further reduced, and the discharge from 3a is being pushed forward. The upper right, 270 ° position further swivels 90 °, which shows that a complete discharge system is created and the outer scroll teeth enter a closed system that creates a new enclosed space.

The above four operation diagrams are different from the orbiting scroll in that the orbiting scroll having the boss portion and the arc of R ₁ and R ₄ are combined to form a seal line with the periphery of the orbiting scroll boss portion. Although it is an operation diagram with a fixed scroll, this embodiment shows a structure effective for a blower or the like having a low compression ratio in one and a half turns, but when a compressor or a vacuum pump is compatible with a high compression ratio, The scroll fluid machine for high compression ratio with less leakage can be configured by increasing the number of scroll turns by two or two and a half turns.

Next, the conventional scroll cannot have a long tooth length, which is a drawback in the meshing structure. The bearing cannot be fitted at the radial load position. Cannot be a double-sided support bearing. The pink rank cost, assembly, and processing accuracy cannot be simplified. However, in the embodiment of FIG. 1 of the present invention which overcomes the above problems, the 4a boss portion of the 4 orbiting scroll has 4
b Build boss wall. A 5 drive eccentric shaft is fitted to the outside of the orbiting scroll disk portion of the 4b boss wall so as to be rotatable and orbitable via 8 bearings. As a result, the radial load applied from the orbiting scroll teeth to the boss can be received at the load position.

In this 4 orbiting scroll, 8 boss bearings are fitted on the 3 fixed scroll side of the 4b boss wall, 5 drive eccentric shaft and S dimension, and an eccentric position via a 12 pin crank, and K. The dimension is 11 in the same eccentric direction as the drive eccentric shaft.
It is fitted in one frame with pink rank base point bearings. 1
(5) The rotation prevention eccentric shaft is attached to the side surface of the orbiting scroll and the bearing lid with the same eccentricity as the pin crank through the bearing. When the 5a drive shaft is rotated in this configuration, the 5th drive eccentric shaft rotates about the K dimension as a radius, and at this time, the 8th boss bearing frees the 5th drive eccentric shaft and the 4a orbiting scroll boss portion.
The 5-drive eccentric shaft tries to rotate the 4-orbiting scroll, but the 12-pin crank is eccentric with this drive eccentric shaft, and the 12-pin crank has a K-size centered on the 11-pin crank base point bearing. It becomes a turning motion in the radius, and by supporting two or more points with the 15 rotation prevention eccentric shaft, the runout and rotation are prevented, and therefore the 4 orbiting scroll does not rotate according to the 5 drive eccentric shaft, but follows the turning motion of this 12 pin crank. Swirl with S dimension radius. That is, FIG.
The compression action is performed by the scroll turning shown in FIG.

Further, since the 12-pin crank is constructed in the 4a orbiting scroll boss portion, the radial load applied to the 4 orbiting scroll is also loaded by this bearing, so that it is supported on both sides and the width of the scroll teeth becomes large. Withstand enough. Further, since there is a 4b boss wall, the pressure on the discharge side does not leak to the suction side, so that high volumetric efficiency can be maintained.

Next, as shown in FIG. 2, if the scroll compression units are arranged in two blocks in parallel, the 12-pin crank is made Z-shaped, and the four-orbit scroll is operated by shifting left and right 180 ° by 2K, and the discharge flow rate. Not only can the double value be secured, but the 180 ° phase-shifted turning makes the dynamic balance perfectly balanced, enabling compact and quiet operation.

FIG. 3 is a two-stage scroll fluid machine which can be constructed by taking advantage of the two-block parallel operation, and is extremely effective for a high pressure compressor and a high vacuum pump. Ie 6,
The fluid sucked from the first-stage suction port passes through 6a, the first-stage discharge port, is cooled by the intercooler 17 and is sucked again from 6b, the second-stage suction port, and is compressed and discharged to the 7,2-stage discharge port in two stages. It The 12-pin crank is formed in a Z shape, and the scroll blocks 3 and 4 on the right side 5 drive shaft side are set as one stage and 3a4b.
The scroll block has two stages, and in order to equalize the compression ratio of each stage, the tooth height of the scroll teeth of each stage is adjusted. The two-stage high-pressure compressor and vacuum pump such as reciprocating type and roots type are complicated in shape, large in size, and expensive, but the structure according to the present invention makes use of the features of the scroll fluid machine. It can be used in small size and low cost.

FIG. 4 shows a conventional scroll fluid machine having a cantilever bearing with 12, pin cranks 4, a orbiting scroll 4a boss portion supported at the left end, and the orbiting motion is performed by the 4a boss portion. With the above construction, the bearing is supported on both sides, the orbiting accuracy is improved, the scroll tooth length can be lengthened, and the operating capacity can be increased.

With respect to the scroll shape, depending on the size of the drive eccentric shaft, the size of the orbiting scroll boss a can be freely selected according to the determination of the bearing to be fitted, and the arc-based scroll teeth that can be selected according to the pressure to be used can be selected. In addition, since the internal tooth top of the fixed scroll maintains a seal shape adapted to the swing of the orbiting scroll, it has a scroll tooth profile with high sealing performance.

[0022]

【The invention's effect】

(1) By constructing the orbiting scroll with the boss portion, the radial load applied to the orbiting scroll teeth can be received at the load position, so that the boss bearing can be selected small and the drive shaft can be short. It became possible to plan.

(2) By constructing the pin crank in the orbiting scroll boss portion, the processing, assembly and cost are simplified, and the orbiting scroll can be supported by supporting both sides.
The bearing can be selected small.

(3) Since the orbiting scroll can be supported on both sides, the orbiting scroll does not shake and the scroll tooth length can be increased.

(4) The pin crank as shown in FIGS.
By adopting a Z-type dual-use type, the capacity is doubled by making the scroll into two blocks, and the scroll is arranged in series with one or two stages to form a two-stage type, which is a compact high-performance model that was not previously thought. It can be configured as a compression type.

If the bearings used in the present invention are of the grease-enclosed type, an oil-free scroll type fluid machine can be manufactured by constructing a scroll mesh with a minute gap.

[Brief description of drawings]

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

FIG. 2 is a vertical sectional view showing a composite type in an embodiment according to the present invention.

FIG. 3 is a two-stage vertical sectional view of an embodiment according to the present invention.

FIG. 4 is a vertical cross-sectional view of a scroll fluid machine having a conventional structure provided with a pin crank according to an embodiment of the present invention.

FIG. 5 is a basic view of scroll teeth and meshing in an embodiment according to the present invention.

FIG. 6 is a scroll compression operation diagram in the embodiment according to the present invention.

FIG. 7 is a vertical cross-sectional view showing a conventional scroll fluid machine at a pin crank position.

FIG. 8 is a meshing diagram of conventional scroll teeth.

FIG. 9 is a basic view of a conventional scroll tooth.

[Explanation of symbols]

1 ... Frame 2 ... Bearing lid 3 ... Fixed scroll 4 ... Orbiting scroll 4a ... Orbiting scroll boss 5a ... Drive shaft 12 ... Pin crank 13 ... Pin crank bearing 15 ... Rotation prevention eccentric shaft K eccentricity 17a of ...... eccentric drive shaft, 17b ... turning diameter S ...... pin crank eccentricity of the fluid filled space l ...... orbiting scroll

Claims (5)

[Claims] 1. A boss portion comprising a semicircular arc and a semicircular arc on the opposite side obtained by adding 1/2 of the tooth thickness to the semicircular arc is provided at the center of the front surface of the orbiting side disk, and the semicircular arc is used as a reference. An orbiting scroll in which semicircular arcs with different radii are sequentially connected from the center to the outer circumference in a scrolling manner for each semicircle, and a central part that does not form a boss part such as that provided on the orbiting scroll on the front surface of the fixed side disk Form, the inner tip of the scroll is orbiting scroll,
Provided so as to form a seal line with the central part and the inside of the tooth,
On the basis of the same standard as the orbiting scroll, semi-circular arcs with different radii from the inner tip of this scroll toward the outer periphery are sequentially connected to each other in a semi-circular manner in a scroll shape. A compression chamber is formed by meshing the fixed scroll, and when the suction is completed by the mutual scrolls, the inner end of the fixed scroll forms the center of the orbiting scroll and the seal lines with the inner side of the teeth. In addition, a scroll type fluid machine characterized by swinging an orbiting scroll. 2. An eccentric drive shaft is fitted to a boss portion of an orbiting scroll via a bearing, and the same eccentricity as the eccentric drive shaft further eccentric to this eccentric drive shaft is provided adjacent to the boss wall at the left end. Fit the pin crank with the pin crank bearing,
The scroll type fluid machine according to claim 1, wherein the other end of the pink rank and the rotation preventing eccentric shaft fitted to the bearing lid are used as the turning base points. 3. A Z-shaped pin crank having two eccentric pin cranks at 180 ° positions is arranged in the center of an orbiting scroll boss portion fitted with an eccentric drive shaft. 180 ° to the left and right through the axis
The scroll type fluid machine according to claim 1, wherein two orbiting scrolls are further provided in parallel with the orbiting scroll in phase, and two series of scroll compression mechanisms that mesh with the fixed scroll are configured. 4. A Z-shaped pin crank, in which two eccentric pin cranks are further arranged at 180 ° positions, is arranged in the center of a first stage orbiting scroll boss portion fitted with an eccentric drive shaft. The orbiting scroll on the right side and the two-stage side on the left side is provided in 180 ° phase via the rotation prevention eccentric shaft, and the scroll compression mechanism meshed with the fixed scroll is connected in series from the one-stage side to the two-stage type. The scroll type fluid machine according to claim 1, which is configured. 5. An eccentric drive shaft is fitted to the rear side of an orbiting scroll disk, and a pin crank is fitted to a tip of a scroll tooth length of an orbiting scroll boss at a position further eccentric to the eccentric drive shaft via a bearing. The scroll type fluid machine according to claim 1, wherein the scroll type fluid machine is mounted.