JPH02201075A - Fluid compressor - Google Patents

Abstract

PURPOSE:To reduce sliding loss in a fluid compressor constructed in such an arrangement, that a piston rotor is fitted in a cylinder within an enclosed chamber and that a spiral blade is fitted in a spiral groove formed at the periphery of this rotor, by making the cylinder with an inside dia. smaller than its axial length. CONSTITUTION:A motor stator 5 is fixed to the inner surface of an enclosed case 2, and a cylinder 7A is fitted on a motor rotor 6 arranged inside thereof, wherein the two ends are supported rotatably by bearings 8A, 9A, which are provided with a discharge port 18 and a suction port 17, respectively. A rotor piston 10A is fitted in this cylinder 7A eccentrically in an amount (e). This rotor 10A is provided at its periphery with a spiral groove 12 which reduces the pitch gradually from the suction toward discharge side, and a spiral blade 15A is fitted in this spiral groove 12 in such a way that it can advance and retreat freely. Therein the cylinder 7A shall have an inside dia. dA which is smaller than it axial length A.

Description

Detailed Description of the Invention (Objective of the Invention) (Industrial Application Field) The present invention relates to a fluid compressor suitable for, for example, a compressor that compresses refrigerant gas in a refrigeration cycle, and particularly relates to a fluid compressor with an improved cylinder. Regarding compressors.

(Prior Art) Conventionally, this type of fluid compressor has been constructed as shown in FIG.

This fluid compressor 1 is not publicly known and has a motor section 3, a compression section 4, etc. built in a sealed case 2.

The motor section 3 includes a substantially annular motor rotor 6 within a substantially annular motor stator 5 fixed to the inner peripheral surface of the sealed case 2.
has been set up.

The compression part 4 has a cylindrical cylinder 7 fixedly fitted into the center hole of the motor rotor 6, and both ends of the cylinder 7 in the axial direction are fixed. ! It is rotatably supported by bearings 8 and 9 fixed to the inner surface of the fly case 2, and is airtightly closed.

A cylindrical rotor piston 10 having a smaller diameter than the inner diameter of the cylinder 7 is arranged along the axial direction of the cylinder 7 .

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

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

Further, in an engagement groove (not shown) bored in the outer circumferential surface of the right end in the figure of the rotor piston 10, a drive pin 11 that protrudes radially from the inner circumferential surface of the cylinder 7 is arranged along the radial direction of the cylinder 7. It is inserted so that it can move forward and backward.

Therefore, when the motor unit 2 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 bottle 11. It rotates with a part of it in contact with the inner circumferential surface of the cylinder 7.

A spiral groove 12 is formed on the outer peripheral surface of the rotor piston 10 and extends in the axial direction.

The grooves 12 are formed such that the pitch thereof gradually decreases from the right end to the left end of the cylinder 7 in the figure, that is, from the suction pipe 13 side to the discharge pipe 14 side of the cylinder 7.

A spiral blade 15 is fitted into this groove 12, and each part of the blade 15 can move forward and backward with respect to the groove 12 along the radial direction of the rotor piston 10.

Further, the outer circumferential surface of the blade 15 slides on the inner circumferential surface of the cylinder 7 while being in close contact with the inner circumferential surface of the cylinder 7 .

This blade 15 is made of an elastic material such as Teflon, and is installed in the groove 12 by inserting it into the groove 12 using its elasticity.

The space between the inner circumferential surface of the cylinder 7 and the outer circumferential surface of the rotor piston 10 extends along the axial direction of the cylinder 7, and the blade 1
5 into a plurality of working chambers 16, 16...

Each working chamber 16 is defined between two adjacent turns of the blade 15, and the rotor piston 1
0 and the inner circumferential surface of the cylinder 7 to the next contact point, forming a substantially crescent shape. These working chambers 16
The volume gradually decreases from the suction side to the discharge side of the cylinder 7.

Further, a suction port 17 extending in the axial direction of the bearing 9 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 into the inside of the sealed case 2.

In the fluid compressor 1 configured in this manner, when the motor section 3 is energized, the motor rotor 6 rotates, and the cylinder 7 rotates together with the motor rotor 6.

Furthermore, at the same time, the rotor piston 10 is rotated with a portion of its outer circumferential surface in contact with the inner circumferential surface of the cylinder 7 .

Due to such relative rotational movement between the rotor piston 10 and the cylinder 7 , refrigerant gas is sucked into the cylinder 7 through the suction pipe 13 and the suction port 17 .

This refrigerant gas is confined between two adjacent windings of the blade 15, and the working chambers 16, 16...
・Sequentially transferred to.

Since the volumes of these 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. be done.

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

FIG. 4 shows another conventional fluid compressor 20. As shown in FIG. This fluid compressor 20 has a motor section 3 and a compression section 4 arranged side by side in a sealed case 2, and one end (first end) of a rotating shaft 21 fitted and fixed in a center hole of a motor rotor 6. 4) is fixed to one end (right end in the figure) of the rotor piston 10, so that only the rotor piston 10 is rotated.

Other than this, the configuration is the same as the fluid compressor 1 shown in FIG. 3, so parts in FIG. 4 that are common to those in FIG.

(Problems to be Solved by the Invention) However, in the fluid compressor 1 shown in FIG. 3, the bearing 8.
There is a problem that the sliding loss of No. 9 is large.

That is, in the fluid compressor 1, both ends of the cylinder 7 in the axial direction are extended in the axial direction around the outer peripheries of the left and right bearings 8 and 9 in the figure, and these extensions are used as sliding parts of the bearings 8 and 9.

In addition, since the inner diameter d of the cylinder 7 is relatively large with respect to the effective length l of the cylinder 7 in the axial direction, the sliding area between the extended portion of the cylinder 7 and the bearings 8 and 9 is large, so that sliding loss is reduced. A major problem is that the efficiency of the motor ri53 is not high.

Moreover, since the sliding loss of the bearings 8 and 9 increases in proportion to the square of the rotational speed of the cylinder 7 and the rotor piston 10, it increases significantly as the rotational speed of the cylinder 7 and the rotor piston 10 increases.

Furthermore, in the conventional fluid compressor 20 shown in FIG. , since the cylinder 7 is stationary, there are sliding parts between a part of the outer circumferential surface of the rotor piston 10 and the inner circumferential surface of the cylinder 7, and sliding parts between the outer circumferential surface of the blade 15 and the inner circumferential surface of the cylinder 7. There is a problem in that the sliding loss is large.

Therefore, the present invention has been developed in consideration of the above circumstances.
The purpose is to reduce sliding loss in sliding parts such as bearings,
An object of the present invention is to provide a fluid compressor that can improve efficiency.

[Structure of the invention]

(Means for Solving the Problems) The present invention is characterized in that the inner diameter of the cylinder is relatively shorter than the axial length of the cylinder, and is configured as follows.

That is, the present invention provides a cylinder having a fluid suction side end and a fluid discharge side end, a rotor piston built in the cylinder eccentrically so that a part thereof contacts the inner circumferential surface thereof,
The rotor piston is wound spirally around the outer periphery of the rotor piston so that the pitch gradually decreases from the suction side end toward the discharge end side, thereby closing the gap between the rotor piston and the cylinder along the axial direction of the cylinder. In the fluid compressor, the cylinder has an inner diameter shorter than an axial length thereof.

(Function) Since the inner diameter of the cylinder is reduced, the sliding area of a sliding part such as a bearing that slides on this cylinder is reduced.

Therefore, since it is possible to reduce the sliding loss in these sliding parts, it is possible to improve the durability and efficiency of these sliding parts.

(Example) An example of the present invention will be described below based on FIGS. 1 and 2. Note that in FIGS. 1 and 2, parts common to those shown in FIGS. 3 and 4 are given the same reference numerals.

FIG. 1 is a longitudinal cross-sectional view showing the overall configuration of an embodiment of the present invention. As shown in FIG. etc. are built-in.

The motor section 3 includes a substantially annular motor rotor 6 within a substantially annular motor stator 5 fixed to the inner peripheral surface of the sealed case 2.
has been set up.

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

A cylindrical rotor piston 10A having a smaller diameter than the inner diameter of the cylinder 7A is arranged along the axial direction of the cylinder 7A.

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

Both ends of the rotor piston IOA are bearings 8A.

9A, each of which is rotatably supported.

In addition, a drive pin 11 protruding radially from the inner circumferential surface of the cylinder 7A is located in an engagement groove (not shown) bored in the outer circumferential surface of the right end portion of the rotor screw 1-IOA in the figure.
It is inserted so that it can move forward and backward along the radial direction.

Therefore, when the cylinder 7A rotates integrally with the motor rotor 6 by energizing the energizing section 2, the rotational force of the cylinder 7A is transmitted to the rotor piston 10A via the drive bottle 11. A portion of the IOA rotates while being in contact with the inner peripheral surface of the cylinder 7A.

A spiral groove 12 extending in the axial direction is formed on the outer peripheral surface of the rotor piston IOA.

This full 12 pitch is from the right end to the left end in the figure of the cylinder 7A, that is, the suction pipe 13 of the cylinder 7A.
It is formed so that it gradually becomes smaller from the side toward the discharge pipe 14 side.

A spiral blade 15A is fitted into this groove 12, and each part of the blade 15A can move forward and backward with respect to the groove 12 along the radial direction of the rotor piston 10A.

Further, the outer circumferential surface of the blade 15A slides on the inner circumferential surface of the cylinder 7Δ while being in close contact with the inner circumferential surface of the cylinder 7A.

This blade 15A is made of an elastic material such as Teflon, and is installed in the groove 12 by inserting it into the groove 12 using its elasticity.

The space between the inner circumferential surface of the front two cylinders 7A and the outer circumferential surfaces of the rotor screws 1 to 10A is partitioned into a plurality of working chambers 16, 16, . . . by blades 15A along the axial direction of the cylinder 7A.

Each working chamber 16 is defined between two adjacent windings of the blade 15A, and extends along the blade 15 from the contact point between the rotor piston IOA and the inner peripheral surface of the cylinder 7A to the next contact point. form. The volumes of these working chambers 16 gradually become smaller from the suction side to the discharge side of the cylinder 7.

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

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

In the fluid compressor 1A configured in this way, the motor section 3
When the motor rotor 6 is energized, the motor rotor 6 rotates, and the cylinder 7A rotates together with the motor rotor 6.

Furthermore, at the same time, the 〇-Taviston IOA is rotated with a portion of its outer circumferential surface in contact with the inner circumferential surface of the cylinder 7A.

Due to such relative rotational movement between the rotor piston IOA and the cylinder 7A, refrigerant gas is sucked into the cylinder 7A through the suction pipe 13 and the suction port 17.

This refrigerant gas is trapped between two adjacent windings of the blade 15△, and the working chamber 16.16 on the discharge side.
... will be sequentially transferred to...

The volume of these working chambers 16, 16... is the cylinder 7A
Since the refrigerant gas gradually becomes smaller as it goes from the suction side to the discharge side, the refrigerant gas is gradually compressed by the bolts that are sequentially transferred to the discharge side.

The compressed refrigerant gas is then discharged into the sealed case 2 through the discharge port 18 and further returned into the refrigeration cycle through the discharge pipe 14.

Then, the fluid compression 11A makes the length of the inner diameter dA of the cylinder 7A shorter than the axial effective length IA of the cylinder 7A, and accordingly, the INl receivers 8A, 9A, the rotor piston IO
The main feature is that the diameters of A, the blade 15A, etc. are appropriately reduced.

Therefore, according to the fluid compressor 1A of this embodiment, it is possible to reduce the outer diameter of the sliding parts of the left and right bearings 8A and 9A in the figure, which rotatably support both axial ends of the cylinder 7A. Therefore, the sliding area of the sliding portion between the cylinder 7Δ and the bearings 8A, 9A can be reduced.

As a result, it is possible to reduce sliding loss and improve durability in these sliding parts.

Thereby, it is possible to improve the efficiency of the motor section 3 that rotationally drives the cylinder 7A and the rotor piston 10, and therefore it is possible to improve the efficiency of the compressor.

In addition, since the inner diameter dA of the cylinder 7A is reduced, the center hole, that is, the hollow part, of the motor rotor 6 into which the cylinder 7A is fitted can be reduced, so that the rotation of the motor rotor 6 can be stabilized.

FIG. 2 is a longitudinal cross-sectional view showing the overall configuration of another embodiment of the present invention, in which the fluid compressor 20B of this embodiment has an inner diameter dB of the cylinder 7B and an effective axial length IB of the cylinder 7B. The diameter of the bearing 8 [3,
9B and rotor piston 10B are suitably reduced in diameter.

Since the configuration other than this is the same as the fluid compressor 20 shown in FIG. 4, parts in FIG. 2 that are common to those shown in FIG. do.

Therefore, according to this embodiment, it is possible to reduce the sliding area of each sliding portion of the outer circumferential surface of the rotor piston 10B and the outer circumferential surface of the blade 15, which respectively slide on the inner circumferential surface of the cylinder 7B. Accordingly, it is possible to reduce the falling loss in these moving parts, and as a result, it is possible to improve the motor part 3 and improve the efficiency as a compression part.

〔Effect of the invention〕

As explained above, in the present invention, since the inner diameter of the cylinder is made shorter than its axial length, it is possible to reduce the [11 area] between the inner circumferential surface of the cylinder and the sliding part of the sliding bearing. .

Therefore, the sliding loss of these sliding parts can be reduced and the efficiency of the fluid compressor can be improved.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view showing the overall configuration of an embodiment of a fluid compressor according to the present invention, FIG. 2 is a vertical cross-sectional view of another embodiment of the present invention, and FIGS. 3 and 4 are conventional FIG. 2 is a longitudinal cross-sectional view of a fluid compressor. 1, IA, 20.20B...fluid compressor, 2... sealed case, 3... motor section, 4... compression section, 5...
・Motor stator, 6...Motor rotor, 7, 7△,
7B...Cylinder, 8.8A, 8B, 9.9A, 9B
...bearing, 10.10A, 10B...rotor piston, 15...blade, 16...operating empty.

Claims (1)

[Claims] A cylinder having a fluid suction side end and a fluid discharge side end, a rotor piston built into the cylinder eccentrically so as to partially contact the inner peripheral surface thereof, and a rotor piston having a fluid suction side end and a fluid discharge side end; The rotor piston is inserted into a spiral groove formed in a spiral shape such that the pitch gradually decreases from the end toward the discharge end, so that the gap between the rotor piston and the cylinder is adjusted along the axial direction of the cylinder. 1. A fluid compressor having blades partitioning into a plurality of working chambers, wherein the cylinder is formed so that its inner diameter is shorter than its axial length.