JP2753017B2 - Fluid compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to, for example, a fluid compressor suitable for a compressor for compressing a refrigerant gas of a refrigeration cycle, and in particular, an axial direction in a cylinder. The present invention relates to a fluid compressor for introducing a fluid into an intermediate portion and compressing the fluid while sequentially moving the fluid toward both ends.

(Prior Art) Conventionally, as this kind of fluid compressor, there is a fluid compressor configured as shown in FIG.

This fluid compressor 1 is not publicly known, and includes a motor unit 3 and a compression unit 4 in a closed case 2.

The motor unit 3 has a substantially annular motor rotor 6 disposed in a substantially annular motor stator 5 fixed to the inner peripheral surface of the sealed case 2.

The compression portion 4 has a cylindrical cylinder 7 fitted and fixed in the center hole of the motor rotor 6, and a pair of left and right bearings in the figure in which both axial ends of the cylinder 7 are fixed to the inner surface of the closed case 2.
It is rotatably supported by 8, 9 and is airtightly closed.

Inside the cylinder 7, a columnar rotor piston 10 having a smaller diameter than its inner diameter is provided along the axial direction of the cylinder 7.

The center axis A of the rotor piston 10 is eccentric with respect to the center axis B of the cylinder 7 by a distance e, and a part of the outer peripheral surface of the rotor piston 10 is in contact with the inner peripheral surface of the cylinder 7. .

Both ends of the rotor piston 10 are rotatably supported by bearings 8 and 9, respectively.

A drive pin 11 projecting radially from the inner peripheral surface of the cylinder 7 is provided in an engagement groove (not shown) formed in the outer peripheral surface of the right end portion of the rotor piston 10 in the drawing along the radial direction of the cylinder 7. It is inserted to move forward and backward.

Therefore, when the motor 7 is energized and the cylinder 7 rotates integrally with the motor rotor 6, the rotational force of the cylinder 7 is transmitted to the rotor piston 10 via the drive pin 11. Part is cylinder 7
It rotates in contact with the inner peripheral surface of the.

On the outer peripheral surface of the rotor piston 10, a spiral spiral groove 12 extending in the axial direction is formed.

The spiral groove 12 is formed so that its pitch gradually decreases from the right end to the left end of the cylinder 7 in the drawing, that is, from the suction pipe 13 side to the discharge pipe 14 side of the cylinder 7.

A spiral blade 15 is fitted in the spiral groove 12, and each part of the blade 15 is movable with respect to the spiral groove 12 along the radial direction of the rotor piston 10.

Further, the outer peripheral surface of the blade 15 slides on the inner peripheral surface of the cylinder 7 in a state of being in close contact with the inner peripheral surface of the cylinder 7.

The blade 15 is formed with a required thickness t and a required radial height h by using an elastic material such as Teflon. The blade 15 is inserted into the spiral groove 12 by utilizing its elasticity, so that the inside of the spiral groove 12 is formed. It is attached to the back and forth freely.

The space between the inner peripheral surface of the cylinder 7 and the outer peripheral surface of the rotor piston 10 is formed along the axial direction of the cylinder 7 by the blades 15.
Are partitioned into a plurality of working chambers 16, 16,.

Each working chamber 16 is defined between two adjacent turns of the blade 15 and extends approximately from the contact portion of the rotor piston 10 with the inner peripheral surface of the cylinder 7 along the blade 15 to the next contact portion. It is in a state. The volumes of these working chambers 16 gradually decrease from the suction side to the discharge side of the cylinder 7.

Further, a suction port 17 extending in the axial direction and communicating with the suction pipe 13 is formed through the bearing 9.

One end of a discharge hole 18 formed in one of the bearings 8 opens into the discharge-side end of the cylinder 7, and the other end of the discharge hole 18 opens inside the closed case 2.

In the fluid compressor 1 configured as described above, the motor unit 3
Is energized, the motor rotor 6 rotates, and the cylinder 7 rotates integrally therewith.

Further, at the same time, the rotor piston 10 is rotated with a part of the outer peripheral surface thereof in contact with the inner peripheral surface of the cylinder 7.

Such a relative rotational movement between the rotor piston 10 and the cylinder 7 is ensured by regulating means including a drive pin 11 and an engagement groove (not shown) for engaging the drive pin 11, and the blade 15 is also fixed to the rotor piston. It rotates together with 10.

That is, since the blade 15 rotates while its outer peripheral surface is in contact with the inner peripheral surface of the cylinder 7, each part of the blade 15 is close to the contact portion between the outer peripheral surface of the rotor piston 10 and the inner peripheral surface of the cylinder 7. Is pushed into the helical groove 12 and protrudes from the helical groove 12 in the direction of the outer diameter as the distance from the contact portion increases.

When the compression unit 4 is operated, the refrigerant gas is supplied to the suction pipe.
It is sucked into the cylinder 7 through 13 and the suction port 17.

This refrigerant gas is sequentially transferred to the discharge-side working chambers 16, 16,... While being confined between two adjacent windings of the blade 15.

Since the volumes of the working chambers 16, 16,... Gradually decrease from the suction side to the discharge side of the cylinder 7, the refrigerant gas is gradually compressed while being sequentially transferred to the discharge side. .

Then, the compressed refrigerant gas is discharged from the discharge port 18 into the closed case 2, and further returned to the refrigeration cycle through the discharge pipe 14.

As an improved type in which the displacement volume of the fluid compressor 1 configured as described above is increased, a refrigerant gas is sucked from an axial middle portion of the cylinder 7 and the refrigerant gas is sent to both axial end portions of the cylinder 7. It is conceivable that the material is compressed while being sequentially transferred.

In this improved type, a suction hole is radially penetrated and opened at an intermediate portion in the axial direction of the cylinder and the motor rotor, and the suction hole is formed into an annular gap between an outer peripheral surface of the motor rotor and an inner peripheral surface of the motor stator, and a closed case. It communicates with the suction pipe through each inside.

Therefore, the refrigerant sucked into the sealed case from the suction pipe is passed through the annular gap between the motor rotor and the motor stator, through the suction holes of the motor rotor and the cylinder, and sucked into the cylinder.

The fluid compressed at both axial ends of the cylinder is discharged to a discharge pipe through a discharge hole formed in a bearing.

(Problems to be solved by the invention) However, such an improved type has the following problems.

That is, since the cylinder and the motor rotor rotate integrally, the suction holes formed therein also rotate at the same time as the cylinder, so that the liquid loss is large.

Further, since the suction gas passes between the motor rotor and the motor stator in the overheated state and is heated, the volume efficiency is reduced.

Further, such overheating of the suction gas can be prevented by avoiding the position of the motor rotor far from the suction hole. However, there is a problem that the overall size of the compressor is increased and the cost is increased.

Therefore, the present invention has been made in view of the above circumstances,
An object of the present invention is to provide a fluid compressor capable of improving efficiency and reducing costs.

[Configuration of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention is configured as follows.

That is, the present invention provides a cylinder, a rotatable rotor piston housed eccentrically in the cylinder so as to partially contact the inner peripheral surface thereof, and rotating both ends of the rotor piston and the cylinder in the axial direction. While freely supporting, a pair of bearings that hermetically support both ends of the cylinder, and a spiral groove is formed on the outer periphery of the rotor piston so that the pitch gradually decreases along different axial directions. In the fluid compressor, an elastic blade is inserted into the spiral groove so as to be able to advance and retreat, and the blade partitions the gap between the cylinder and the rotor piston into a plurality of working chambers. An introduction hole communicating with the suction hole provided on the rotor piston is formed in the axial direction. An equalizing hole communicating with the introduction hole is bored in the axial direction of the rotor piston, and one end of the equalizing hole is communicated with a gap of the other bearing. .

(Operation) When the fluid compressor is operated, a fluid such as a refrigerant gas is sucked into the cylinder at an axially intermediate portion thereof through the suction pipe, the suction hole of the bearing, and the introduction hole of the rotor piston.

The sucked refrigerant is guided by the helical blade, is sequentially transferred so as to be distributed to the left and right sides of the cylinder in the axial direction, is compressed during that time, and is discharged into the sealed case through the discharge hole of the bearing. From the refrigeration cycle through the discharge pipe.

Therefore, according to the present invention, the suction gas such as the refrigerant is sucked into the axially intermediate portion of the cylinder, and is distributed to the left and right sides in the axial direction of the cylinder for compression. be able to.

Also, fluid such as refrigerant sucked into the suction pipe is sucked into the cylinder through the introduction hole of the rotor piston,
Since the number of members that contact the fluid is small and the contact area can be reduced, overheating of the fluid can be reduced. Further, since the pressure balance of the pair of left and right bearings can be balanced by the pressure equalizing holes, thrust acting on the bearings can be reduced.

(Example) Hereinafter, an example of the present invention will be described with reference to FIGS.

FIG. 1 is a longitudinal sectional view showing the overall configuration of an embodiment of the present invention. In the figure, a fluid compressor 21 has a motor case 23, a compression unit 24 and the like built in a closed case 22.

The motor part 23 has a substantially annular motor rotor inside a substantially annular motor stator 25 fixed to the inner peripheral surface of the closed case 22.
26 are arranged.

The compression portion 24 has a cylindrical cylinder 27 fixedly fitted in the center hole of the motor rotor 26, and both ends in the axial direction of the cylinder 27 are fixed to the inner surface of the sealed case 22.
It is rotatably supported by 28 and 29 and is airtightly closed.

Inside the cylinder 27, a columnar rotor piston 30 having a smaller diameter than its inner diameter is provided along the axial direction of the cylinder 27.

The center axis A of the rotor piston 30 is eccentric with respect to the center axis B of the cylinder 27 by a distance e, and a part of the outer peripheral surface of the rotor piston 30 is in contact with the inner peripheral surface of the cylinder 27. .

Both ends of the rotor piston 30 are rotatably supported by bearings 28 and 29, respectively.

One bearing 29 is provided with a suction hole 31 penetrating in the axial direction thereof, and a suction pipe 32 communicating with the suction hole 31 is provided in a sealed case.
Connected to 22.

A drive pin 31b radially protruding from the inner peripheral surface of the cylinder 27 advances and retreats along the radial direction of the cylinder 27 in an engagement groove 31a formed in the outer peripheral surface of the right end portion of the rotor piston 30 in the drawing. It is freely inserted.

Therefore, when the motor portion 23 is energized and the cylinder 27 rotates integrally with the motor rotor 26, the rotational force of the cylinder 27 is transmitted to the rotor piston 30 via the drive pin 31b, and as a result, Part is cylinder 27
It rotates in contact with the inner peripheral surface of the.

An introduction hole 33 having a required diameter is formed in the axial center of the right half of the rotor piston 30 in FIG. 1 in the axial direction.

The outlet end 33a of the introduction hole 33 is bent almost at a right angle in the radial direction at the axial middle part of the rotor piston 30, extends to the outer peripheral surface of the rotor piston 30, and opens at the axial middle part in the cylinder 27. The inlet end 33b of the introduction hole 33 communicates with the suction hole 31 of the bearing 29.

Therefore, the fluid such as the refrigerant gas sucked from the suction pipe 32 passes through the suction hole 31 and the introduction hole 33 of the bearing 29 sequentially, and is sucked into the axially intermediate portion in the cylinder 27.

Further, a pressure equalizing hole 34 having a diameter smaller than that of the introduction hole 33 is formed in the axial center of the left half of the rotor piston 30 in the left half of FIG. .

The outlet 34a of the pressure equalizing hole 34 communicates with the gap 28a of the other bearing 28.

Therefore, a part of the fluid introduced into the introduction hole 33 is introduced into the pressure equalizing hole 34 and guided to the gap 28a of the bearing 28, and equalizes the pressure in the gap 28a.

For this reason, since the pressures at both ends of the rotor piston 30 when the fluid is introduced into the introduction hole 33 can be substantially balanced, the rotor piston 30 received by the pair of left and right bearings 28 and 29 can be used.
Thrust can be reduced.

On the outer peripheral surface of the rotor piston 30, a spiral spiral groove 35 extending in the axial direction is formed.

Two spiral grooves 35 are formed in the left and right directions around the outlet end 33a of the introduction hole 33 so that the pitch gradually decreases toward both axial ends (left and right ends in the figure) of the rotor piston 30. Have been.

A helical blade 36 shown in FIG. 2 is fitted in these two helical grooves 35 and 35 so as to be able to advance and retreat, respectively. It is free to advance and retreat along.

Further, the outer peripheral surface of the blade 36 slides on the inner peripheral surface of the cylinder 27 in a state of being in close contact with the inner peripheral surface of the cylinder 27.

The blade 36 is made of an elastic material such as Teflon, and is inserted into the spiral groove 35 by utilizing its elasticity, so that the blade 36 is mounted in the spiral groove 35 so as to be able to move forward and backward.

The space between the inner peripheral surface of the cylinder 27 and the outer peripheral surface of the rotor piston 30 is formed along the axial direction of the cylinder 27 by a blade 36.
Are divided into a plurality of working chambers 37, 37.

Each working chamber 37 is defined between two adjacent turns of the blade 36, and extends almost from the contact portion between the rotor piston 30 and the inner peripheral surface of the cylinder 27 along the blade 36 to the next contact portion. It is in a state. The volumes of these working chambers 37 gradually decrease from the axially intermediate portion of the cylinder 27 to both ends thereof.

The pair of bearings 28, 29 are provided with discharge holes 38a, 38b penetrating in the axial direction at the outer peripheral portions thereof.
The inside of the cylinder 27 and the inside of the sealed case 22 are communicated via 8b. Therefore, the liquid discharged into the closed case 22 through the discharge holes 38a and 38b is discharged to the outside such as a refrigeration cycle through the discharge pipe 39 provided in the closed case 22.

 Next, the operation of the present embodiment will be described.

When the motor section 23 of the fluid compressor 21 is energized, the motor rotor 26 rotates, and the cylinder 27 rotates integrally therewith.

Further, at the same time, the rotor piston 30 is rotated with a part of its outer peripheral surface in contact with the inner peripheral surface of the cylinder 27.

Such a relative rotational movement between the rotor piston 30 and the cylinder 27 is ensured by a regulating means including a drive pin 31b and an engagement groove 31a engaging the drive pin 31b, and the blade 36 is also integrated with the rotor piston 30. To rotate.

That is, since the blade 36 rotates in a state where its outer peripheral surface is in contact with the inner peripheral surface of the cylinder 27, each portion of the blade 36 approaches the contact portion between the outer peripheral surface of the rotor piston 30 and the inner peripheral surface of the cylinder 27. It is pushed into the spiral groove 35, and projects in a direction of projecting in the outer diameter direction from the spiral groove 35 as it moves away from the contact portion.

When the compression unit 24 operates, the refrigerant gas is supplied to the suction pipe 3.
2, cylinder 27 through suction hole 31 and introduction hole 33 respectively
Is sucked into the middle part in the axial direction.

In a state where the refrigerant gas is confined between two adjacent windings of the pair of left and right blades 36, 36, the refrigerant gas is distributed in the left and right direction in FIG. Are sequentially transferred to

The capacity of these working chambers 37, 37...
, The refrigerant gas gradually decreases as it goes to the discharge holes 38a, 38b on the discharge side, so that the refrigerant gas is gradually compressed while being sequentially transferred to each discharge side.

Then, the compressed refrigerant gas is supplied to the left and right discharge ports 38a, 38b.
Is discharged into the closed case 22 and then returned to the refrigeration cycle through the discharge pipe 39.

Therefore, according to the present embodiment, one rotor piston
Since two fluid compression portions are formed on the top 30 in the left-right direction in the figure with the outlet 33a of the introduction hole 33 as the center, the compression efficiency can be improved.

Further, the refrigerant gas does not pass through the overheated portion such as the motor rotor 26, but passes through the rotor piston 30, the introduction hole 33, and the cylinder 27.
As a result, the volume efficiency of the refrigerant gas can be prevented from lowering due to overheating of the gas.

Further, a part of the refrigerant gas introduced into the introduction hole 33 is
34 to guide the gap 28a of one bearing 28 to balance the pressure of the pair of left and right bearings 28, 29, reduce the thrust of the rotor piston 30 loaded on these bearings 28, 29, The sliding loss can be reduced.

As shown in FIGS. 3 and 4, the outer peripheral surface OUT of the blade 36 is in airtight contact with the inner peripheral surface of the cylinder 27, and the blade 36 has a high-pressure side on its side in the thickness direction.
Since the working chambers 37, 37 of Ph and the low-pressure side Pl are airtightly partitioned, high rigidity and a low coefficient of friction are required.

On the other hand, since the inner peripheral surface IN portion of the blade 36 enters and exits while being elastically deformed into the spiral groove 35, high elasticity is required.

Therefore, in order to gradually reduce the Young's modulus of the blade 36 from the inner peripheral surface IN side toward the outer peripheral surface OUT side, as shown in FIGS. 5 (A), (B) and (C), for example, a polyimide-based plastic is used. As a matrix, a composite material filled with glass, carbon fiber, and glass balloon can be used.

5A to 5C show longitudinal sections of the blade 36, respectively. FIG. 5A shows the distribution density of the glass fibers 36b filled in the matrix 36a of the blade 36, and FIG.
From the inner peripheral surface IN toward the outer peripheral surface OUT of the blade 36, thereby increasing the Young's modulus of the inner peripheral surface IN portion of the blade 36 and reducing the Young's modulus at the outer peripheral surface OUT portion. High rigidity and low friction coefficient are achieved.

The blade 36 in FIG. 5 (B) indicates the distribution density of the glass balloon 36c filled in the matrix 36a.
6 is gradually raised from the inner peripheral surface IN to the outer peripheral surface OUT, thereby increasing the Young's modulus of the inner peripheral surface IN portion of the blade 36 to achieve high elasticity, and at the outer peripheral surface OUT portion side. The Young's modulus is lowered to improve high rigidity and low coefficient of friction.

Further, the blade 36 shown in FIG. 5 (C) fills the matrix 36a with glass fibers 36b in a concentric arc shape from the high pressure Ph side to the low pressure Pl side, so that the Young on the inner surface IN side of the blade 36 is filled. While increasing the rate
The Young's modulus of the part is reduced to achieve high rigidity and a low coefficient of friction.

Since the blade 36 is made of such a composite material, the elastic deformation at the outer peripheral portion of the blade 36 and the friction coefficient can be reduced.
Gas leakage between 37 and 37 can be reduced, and the compression efficiency can be improved.

On the other hand, since the inner peripheral portion of the blade 36 is easily elastically deformed, a sliding loss between the inner peripheral portion and the spiral groove 35 into and out of the blade 36 can be reduced.

Note that the outer peripheral surface OUT of the blade 36 may be coated with, for example, amorphous ceramics, whereby the coefficient of friction is reduced, the sliding loss is reduced, and the efficiency can be improved.

〔The invention's effect〕

As described above, the present invention suctions fluid into the axially intermediate portion of the cylinder through the introduction hole formed in the rotor piston, and sequentially transfers the fluid to the axially opposite ends of the cylinder so as to be distributed left and right, respectively, Since the compressed fluid is compressed during this time, it is possible to prevent the volume efficiency of the fluid from lowering through the superheated portion such as the motor rotor, and as a result, it is possible to improve the compression efficiency.

Further, since the pressure of the pair of left and right bearings can be balanced by the pressure equalizing hole communicating with the introduction hole, the thrust of the bearing that rotatably supports the rotor piston can be reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing the overall configuration of one embodiment of a fluid compressor according to the present invention, FIG. 2 is a perspective view showing the external appearance of the blade shown in FIG. 1, and FIG. 3 is a partially enlarged view of FIG. FIG. 4 is a partially enlarged view showing a further enlarged part of FIG. 3, and FIG. 5 (A)
(C) is a longitudinal sectional view of the blade shown in FIGS. 1 to 4,
FIG. 6 is a longitudinal sectional view of a conventional fluid compressor. 21 fluid compressor, 22 sealed case, 23 motor part, 24 compression part, 27 cylinder, 28, 29 bearing, 2
8a: air gap, 30: rotor piston, 31: suction hole, 32
…… Suction pipe, 33 …… Introduction hole, 33a …… Outlet, 34 …… Equalization hole, 35 …… Spiral groove, 36 …… Blade, 37 …… Working chamber, 38
a, 38b: discharge hole, 39: discharge pipe.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Kanji Sakata 8-8 Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Inside the Home Appliances Research Laboratory, Toshiba Yokohama Office (56) References JP-A-2-176187 (JP, A )

Claims (1)

(57) [Claims] 1. A cylinder, a rotatable rotor piston housed eccentrically in the cylinder so as to partially contact the inner peripheral surface thereof, and rotating both axial ends of the rotor piston and the cylinder. While freely supporting, a pair of bearings that hermetically support both ends of the cylinder, and a spiral groove is formed on the outer periphery of the rotor piston so that the pitch gradually decreases along different axial directions. In the fluid compressor, an elastic blade is inserted into the spiral groove so as to advance and retreat, and the blade partitions the gap between the cylinder and the rotor piston into a plurality of working chambers. An introduction hole communicating with the suction hole provided in the hole is formed in the axial direction. A fluid pressure compressor, characterized in that an equalizing hole communicating with the introduction hole is bored in the axial direction of the rotor piston, and one end of the equalizing hole communicates with a gap of the other bearing. .