JPH11247783A - Fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To optimize a load of a blade, prevent inclination of a blade and suppress abrasion thereof in a fluid machine. SOLUTION: A spiral blade 33 is reciprocably attached to a spiral groove 31 formed on an outer periphery of a roller 21 which can relatively be rotated to a cylinder 17, for determining a space between the cylinder 17 and the roller 21 into a plurality of operation chambers 35. A spacing (e) between an axis of the cylinder 17 and an axis of the roller 21 is 5 mm or less. A load to be applied to the blade 33 can thus be optimized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a helical blade type fluid machine applied to a compressor, an expander, a pump and the like.

[0002]

2. Description of the Related Art Conventionally, an outline of a helical blade type fluid machine is as follows. A piston-like roller is eccentrically arranged in a cylinder, and a spiral groove having a different pitch is formed on the outer peripheral surface of the roller. By wrapping the blade, working chambers having different volumes are formed in the cylinder from the suction end side to the discharge end side.

[0003] As a result, the rollers taken in from the suction end side by rotating the rollers in the cylinder move sequentially through the working chambers having different volumes and are discharged from the discharge end side.

[0004]

In a helical blade type fluid machine, a space between a cylinder and a roller is divided into a plurality of working chambers by a helical blade.
As shown in FIG.
Spiral grooves 105 with different pitches provided on the outer peripheral surface of
On the other hand, it is incorporated so as to be able to enter and exit freely in a state protruding from the outer peripheral surface and a state immersed therein.

When the blade 101 comes into and out of the spiral groove 105 and falls due to the pressure difference between the working chambers 107, the blade 105 comes into correct contact with the inner wall surface of the cylinder 109. Disappears and the sealing performance deteriorates. In addition, since the side surface of the blade 101 enters and exits while strongly contacting the groove 105, the blade 101 needs to satisfy various conditions such as abrasion resistance. However, until now, for example,
It was designed to clear each condition for abrasion resistance and the like.

However, in order to simultaneously secure high efficiency, high reliability, and the like with respect to set conditions such as pressure and capacity, appropriate dimensional ranges of respective parts are required. The proper dimensional range was not known.

Accordingly, an object of the present invention is to provide a fluid machine in which the dimensions are optimized and high efficiency and high reliability are obtained.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a cylinder and an eccentric arrangement along the axial direction of the cylinder, a part of which is in contact with the inner peripheral surface of the cylinder. A roller that is rotatable relative to the cylinder, a spiral groove that is provided on the outer periphery of the roller and has a different pitch from the suction side to the discharge side of the cylinder, and at least two windings that can freely enter and exit this groove. A fluid machine that is mounted in a state of being wound in six turns and has a helical blade that partitions the cylinder and the roller into a plurality of working chambers, wherein the axis of the cylinder and the axis of the roller are Is set to 5 mm or less.

Alternatively, the inner diameter Dc of the cylinder and the distance e between the axis of the cylinder and the roller are defined as Dc × e ≦ 3.5c.
set in the relationship of m ^2.

Alternatively, the radial width of the blade is set to 8/3.
× emm or more.

Alternatively, the blade thickness in the axial direction is em
m or more.

According to such a fluid machine, the maximum protruding amount of the blade is determined by the distance e between the axes of the cylinder and the roller. By setting the distance between the axes to be 5 mm or less,
Experimental evaluations have shown that the progress of blade wear can be minimized and that there is no tipping.

The load applied to the blade (differential pressure of each working chamber) is proportional to the area between the inner peripheral surface of the cylinder and the outer peripheral surface of the roller. It can be considered that it is almost proportional to the product of the distance e between the centers.

Therefore, the cylinder diameter Dc and the distance e are set to 5 m.
m, it was found that Dc × e ≦ 3.5c
It was confirmed that m ² was the optimal size.

[0015] Thereby, the wear of the blade is suppressed,
A stable operation without falling was obtained. In addition, the sliding loss was small, and operation with low input was enabled.

Further, in order to prevent the leakage of the working chamber and secure the reliability of the blade, there is a relationship between the area of the part where the blade is in the groove and the area of the part outside the groove. The result of the experiment was understood.

Therefore, the radial width is set to 8/3 × emm or more. Further, by setting the thickness of the blade in the axial direction to emm or more, the blade did not fall due to the load. As a result,
Leaks were prevented and high reliability was obtained.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a compressor will be specifically described as a typical example of the present invention with reference to FIGS.

In FIG. 1, reference numeral 1 denotes a sealed case of a helical blade type fluid compressor 3.
Is provided with a suction pipe 5 at the side thereof, and a discharge pipe 7 at the top. In the closed case 1, an electric mechanism 9 as a driving means and a compression mechanism 11 as a compression means are arranged.

The electric mechanism 9 has a stator 13 fixed to the inner periphery of the sealed case 1 and a rotatable rotor 15 provided inside the stator 13.

The compression mechanism 11 has a cylinder 17 whose both ends are open. Both ends of the cylinder 17 are rotatably supported by left and right main bearings 19 and sub bearings 20 fixed to the inner surface of the sealed case 1. ing. Each of the bearings 19, 20 has a boss 19a, into which the end of the cylinder 17 is rotatably fitted.
20a and bases 19b, 20b having a larger diameter than the bosses 19a, 20a and fixed to the inner surface of the closed case 1.
And both ends of the cylinder 17 are hermetically closed.

Inside the cylinder 17, a cylindrical rotor 21 smaller than the inner diameter of the cylinder 17 is provided along the axial direction of the cylinder 17. The center axis A of the roller 21 is set such that the distance e between the axes with respect to the center axis B of the cylinder 17 is 5 mm or less. And it is eccentrically arranged downward in FIG. 1, and a part thereof is in line contact with the inner peripheral surface.

The inner diameter Dc of the cylinder 17 and the distance e between the axes of the cylinder 17 and the roller 21 are represented by Dc × e.
≤3.5 cm ² .

At both ends of the roller 21, spindles 21a and 21b each having a small diameter are provided.
a and 21b are bearing holes 19c and 20c formed in the boss portions 19a and 20a of the main bearing 19 and the sub-bearing 20, respectively.
It is rotatably inserted and supported.

The right shaft 21a of the roller 21 is formed with a square section 25 having a square cross section which functions as a power transmitting surface through which rotational power is transmitted from the cylinder 17 via the Oldham mechanism 23. .

The Oldham mechanism 23 includes a ring-shaped Oldham ring 24 and a transmission pin 27 as shown in FIG.
The inside of the rectangular long hole 26 formed in the Oldham ring 24 is fitted with play to the prism portion 25 of the roller 21, and contacts the central axis A while making surface contact within the range of the long hole 26. The sliding of the Oldham ring 24 is possible in orthogonal directions.

On the outer peripheral surface of the Oldham ring 24,
One end of each of the transmission pins 27, 27 is slidably fitted in a radial direction orthogonal to the longitudinal direction of the long hole 26, and the other end of each of the transmission pins 27, 27 is
Is fitted and fixed in a fitting hole 29 formed in the peripheral wall of the rim.
Thereby, the roller 21 is smoothly slid in the eccentric position with respect to the cylinder 17, and the rotational force of the cylinder 17 is transmitted to the roller 21 via the Oldham mechanism 23. .

Accordingly, the operation of the electric mechanism 9 causes the cylinder 17 to rotate integrally with the rotor 15, whereby the rotational force of the cylinder 17 is transmitted to the roller 2 via the Oldham mechanism 23.
1 and the roller 21
Rotates in synchronization with the rotation of.

On the other hand, a spiral groove 31 is provided on the outer peripheral surface of the roller 21. The spiral groove 31 has the largest pitch P on the suction end side (right side in FIG. 2). The pitch is set so as to gradually decrease toward the discharge end side (left side in the drawing).

In the spiral groove 31, a spiral blade 33 wound by 2 to 6 turns is incorporated so as to be able to move in and out freely by utilizing elastic force. Thereby, each working chamber 35 is formed, and the capacity of the working chamber 35 on the suction end side is the largest. Hereinafter, the volume of each working chamber 35 is set so as to gradually decrease toward the discharge end side, and the final working chamber 35 on the discharge side is formed in the sub-bearing 20, and the closed case 1
It is connected and connected to the discharge hole 37 opened inside. Each working chamber 35 is a substantially crescent-shaped area extending from the contact portion between the roller 21 and the inner peripheral surface of the cylinder 17 along the blade 33 to the next contact portion. The first working chamber 35 on the suction end side is connected and connected to the suction pipe 5 via a main passage 39 provided at the shaft end of the roller 21 and a suction passage 41 provided on the main bearing 19. The refrigerant sucked from the suction pipe 5 into the cylinder 17 is supplied to the first working chamber 3.
5 has been introduced without interruption.

The blade 33 is made of a synthetic resin (for example, PT
FE. PEI. PI), and the radial width W is 8
/ 3 × emm or more. The thickness B in the axial direction is a distance em between the axis of the cylinder 17 and the roller 21.
m or more.

In FIG. 1, reference numeral 43 denotes an oil introduction passage provided in the roller 21. One end of the oil introduction passage 43 communicates with the spiral groove 31, and the other end of the oil introduction passage 43 is on the suction end side. Through a communication hole 45 formed in the main bearing 19, it is connected and connected to an introduction pipe 49 whose suction port 47 faces the bottom of the sealed case 1. Therefore, when the pressure in the closed case 1 rises, the lubricating oil stored in the bottom of the closed case 1 is fed into the groove 31 through the introduction pipe 49, the communication hole 45, and the oil introduction path 43, so that the blade The lubrication at the time of entry and exit of 33 is ensured.

Next, the operation of the fluid compressor thus configured will be described.

First, when power is supplied to the electric mechanism 9, the rotor 1 is turned on.
5 rotates, and the cylinder 17 also rotates integrally with the rotor 15. When the cylinder 17 rotates, the Oldham mechanism 23
, The roller 21 also rotates. As a result, the fluid such as the refrigerant taken into the working chamber 35 on the suction end side is compressed while being sequentially sent to the working chamber 35 on the discharge side in a trapped state, and is discharged from the discharge pipe 7. Become.

During this operation, the load applied to the blade 33 (arrow Fg in FIG. 5) is proportional to the differential pressure between the working chambers 35, 35 partitioned by the blade 33.

When the load applied to the blade 33 is large, the blade 33 is pressed against the low-pressure side surface 31a of the groove 31 by the differential pressure, and the sliding loss increases. In addition, since the portion coming out of the groove 33 may fall down due to the differential pressure, it is necessary to optimize the load applied to the blade 33.

The maximum amount of protrusion of the blade 33 from the groove 31 is twice the distance e between the axis of the cylinder 17 and the roller 21, that is, the amount of eccentricity e. The eccentricity e affects the stability of the blade 33 depending on the size. Regarding this stability, as a result of experimentally evaluating that the wear of the blade 33 did not progress and that the blade 33 did not fall, the eccentricity e was e ≦ e.
It was confirmed that 5 mm was good.

The stability of the blade 33 depends on the inner diameter Dc of the cylinder 17. That is, the load applied to the blade 33 is proportional to the area between the inner peripheral surface 17a of the cylinder 17 and the outer peripheral surface of the roller 21, and as a representative dimension thereof, is approximately proportional to the product of the inner diameter Dc of the cylinder 17 and the eccentricity e. Then you can think about it.

As a result of studying the combination of the inner diameter Dc of the cylinder 17, the eccentricity e, and the synthetic resin used as the material of the blade 33, when the eccentricity e is 5 mm or less, the inner diameter Dc of the cylinder 17 (unit: cm) and the eccentricity The product of e (in cm) is Dc
× e ≦ 3.5 cm ² was confirmed to be good. If the product exceeds 3.5 cm ² , the blade 33 wears out, or in extreme cases, the blade 33 falls down,
In some cases, the vehicle jumped out of the groove 31 and became unable to operate.

By setting the range of the product to 3.5 cm ² or less, the wear of the blade 33 was suppressed, and a stable operation without falling was obtained. As a result, the sliding loss was reduced and operation at a low input became possible, and high efficiency and high reliability were secured.

On the other hand, in order to prevent leakage of the seals in the working chambers 35, 35, as shown in FIG. There is a relationship between the area S1 when the contacting surface is projected on a two-dimensional plane and the area S2 when the part of the blade 33 projecting from the groove 31 is projected on a two-dimensional plane. These relationships indicate that S1 ≧ about S2 / 1/1.
It turned out that setting to 5 is good.

That is, at the maximum eccentric position, the amount of protrusion of the blade 33 from the groove 31 is twice the amount of eccentricity e.
At this time, a part of the blade 33 needs to be in the groove 31. If the minimum value of the insertion margin at this time is a × e, the overlapping area S1 is

S1 = π × ((Dc × 2− (Dc−2 × e) 2)
− (Dc−2 × e−2 × a × e) 2) / 4.

The area S2 protruding from the groove 31 is

S2 = π × ((Dc × 2− (Dc−2 × e) × 2) / 4), where X is the area ratio,

X = S1 / S2 = (a × ((Dc−2 × e) −)
e × 2 × 2) / (Dc−e) Here, in order to satisfy X ≧ 1 / 1.5, a ≧ 2/3. Therefore, the minimum overlap amount is 2/3 times or more of the eccentric amount e. ,
That is, a × e ≧ 2/3 × e, and the radial width W of the blade 33 is W = 2/3 × e + 2 × e = 8/3 × e.

The radial width W of the blade 33 is set to 8/3 × e.
By preventing the leakage between the working chambers 35, 35,
High efficiency could be obtained.

As can be seen from FIG. 5 which is an enlarged view showing the relationship between the cylinder 17 of the blade 33 and the groove 31, the gas load per unit length is considered as the concentrated load Fg. , Fg act from the high-pressure side compression chamber 35 (left side in the drawing) toward the low-pressure measurement compression chamber 35 (right side in the drawing), and act on the midpoint of the radial length of the blade 33 coming out of the groove 31. Act on. This load is applied to groove 3
1 at the low pressure side open end 51. The size is Fm = F
g.

The force Fg caused by the gas force and the force F supported by the groove 31
Since m has a different action point, a rotational moment acts on the blade 33. This rotational moment is transmitted to the blade 33
Is maximized in the state in which it protrudes most, and the moment Mg at this time is the amount of eccentricity e with the opening end 51 of the groove 31 as a fulcrum, so that Mg = e × Fg.
The place supporting the moment Mg is the inner peripheral surface 17a of the cylinder 17 which is in sliding contact with the end 33 on the high pressure side of the blade 33. Assuming that the thickness of the blade 33 is B and the force acting on the high-pressure end 53 of the blade 33 is Fc, the moment Mg is Mg = B × Fc.

Since the blade 33 can support the force of the moment Fg, if Fc = Fg, then B = e from the above two equations.

Therefore, the thickness B of the blade 33 is equal to the eccentricity e.
The thickness may be equal to or greater than
g, and high reliability of the blade 33 can be secured.

As an example of the dimensions of each part set based on the relational expression of the above configuration, the distance between the axes (the amount of eccentricity) e =
2.0 mm, cylinder inner diameter Dc = 60 mm, blade radial direction W = 6.0 mm, and blade thickness = 4.0 mm. In the fluid machine of the helical blade using these dimensions, wear and fall of the blade are reduced. It was confirmed by an experiment that operation with low sliding loss was possible.

With the above configuration, leakage can be prevented and sliding loss can be suppressed, so that high efficiency can be achieved. In addition, since the load acting on the blade 33 can be optimized, high reliability can be ensured.

In the above-described embodiment, the roller rotation type in which the cylinder and the roller are rotated has been described. However, regardless of this type, the helical blade type fluid compressor in which the roller rotates relatively to the cylinder. Another example applicable to the present invention may be applied to a helical blade type fluid machine 55 which is of a roller revolution type in which a cylinder is fixed and a row in the cylinder is turned as shown in FIG.

That is, an electric mechanism 61 composed of a stator 57 and a rotor 59, a shaft 63 to which rotational power is applied from the electric mechanism 61, and an axis of the shaft 63 and e
The Oldham mechanism 67 attached to the eccentric shaft 65
As a result, a roller 71 that is provided with a rotating motion without rotation to a fixed cylinder 69, and a plurality of working chambers 73 provided between the cylinder 69 and the roller 71 are provided on the outer peripheral surface of the roller 71. Spiral blade 7 to partition
5 is provided.

As a result, the refrigerant flowing from the suction pipe 77 is sequentially transferred and discharged from the discharge pipe 79. At this time, the inner diameter Dc of the cylinder 69 and the cylinder 6
The same effect can be obtained by setting the distance e between the shaft centers of the roller 9 and the roller 71, the radial width W and the axial thickness B of the blade 75 to the same conditions as in the above-described embodiment.

The helical blade type fluid machine is
The present invention is not limited to the compressor, and can be applied to an expander, a pump, and the like.

[0055]

As described above, according to the fluid machine of the present invention, it is possible to prevent the blade from falling down and to optimize the load while minimizing abrasion. As a result, it is possible to secure a reliable sealing property and reduce a sliding loss, so that high efficiency and high reliability can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a fluid machine according to the present invention.

FIG. 2 is a perspective view of a roller provided with a spiral blade.

FIG. 3 is an explanatory view of an Oldham mechanism.

FIG. 4 is a schematic plan view in which each ridge line of a cylinder, a roller, and a blade is expressed in a two-dimensional plane when viewed from an axial direction.

FIG. 5 is an enlarged sectional view of a part of a blade and a groove.

FIG. 6 is a schematic sectional view similar to FIG. 1, showing a different type of fluid machine.

FIG. 7 is an explanatory diagram showing a relationship among a blade, a roller, and a cylinder.

[Explanation of symbols]

 17 Cylinder 21 Roller 31 Spiral Groove 33 Blade 35 Working Chamber

Claims (4)

[Claims] 1. A cylinder, a roller disposed eccentrically along an axial direction of the cylinder, a roller capable of rotating relatively to the cylinder with a part thereof being in contact with an inner peripheral surface of the cylinder, and an outer periphery of the roller. And a spiral groove having a different pitch from the suction side to the discharge side of the cylinder, and at least two to six windings are installed so as to freely enter and exit the groove. A fluid machine having a helical blade that partitions a plurality of working chambers between a roller and a roller, wherein a distance e between an axis of the cylinder and an axis of the roller is 5 mm or less. 2. The fluid machine according to claim 1, wherein the inner diameter Dc of the cylinder and the distance e between the axis of the cylinder and the roller are set to satisfy a relationship of Dc × e ≦ 3.5 cm ^2. . 3. The radial width of the blade is 8/3 × emm.
The fluid machine according to claim 1, wherein: 4. The fluid machine according to claim 1, wherein the blade has an axial thickness of emm or more.