JPH02201094A - Fluid compressor - Google Patents

Abstract

PURPOSE:To ensure smooth operation in simple construction and enhance the sealing performance and efficiency of a fluid compressor by constructing it in such an arrangement that a rotor with a spiral blade fitted in a spiral groove formed at the periphery is fitted in a cylinder arranged concentrically with the rotor of an electromotive element in such a way as capable of relative rotation. CONSTITUTION:A stator 5 of an electromotive element 3 is fixed to the inner surface of an enclosed case 2, and a cylinder 7 is fitted on a rotor 6 arranged inside thereof, wherein the two ends are supported rotatably by bearings 8, 9. A piston 11 is fitted in this cylinder 7 as a rotating element eccentrically in an amount (e). This piston 11 is provided at its periphery with a spiral groove 19 reducing its pitch from the suction end side gradually toward the discharge end side, and a spiral blade 21 is fitted in this groove 19 in such a way that it can advance and retreat freely. The space between the cylinder 7 and piston 11 is partitioned by blade 21 into a plurality of working chambers 22, and the fluid sucked into working chambers 22 from a suction hole 23 during the compressor being in operation is compressed one by one to be then discharged from a discharge hole 25.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a fluid compressor for compressing refrigerant gas in a refrigeration cycle, for example.

(Prior Art) Various types of compressors, such as reciprocating type and rotary type, have been known so far. However, in these compressors, the drive section such as a crankshaft that transmits rotational force to the compressor section and the structure of the compressor section are complicated, and the number of parts is large. Furthermore, in order to improve compression efficiency in such conventional compressors, it is necessary to install a check valve on the discharge side, but since the pressure difference on both sides of this check valve is very large, Gas leaks and compression efficiency is low.

In order to solve these problems, it is necessary to improve the dimensional accuracy and assembly accuracy of each component, which increases manufacturing costs. Further, in a conventional compressor, a motor, a drive section that transmits the rotation of the motor, and a compressor section that is driven by the drive section are arranged in series. As a result, the length of the compressor in the rotational axis direction becomes long, resulting in an increase in size.

A screw pump is also shown in US Pat. No. 2,401,189. According to this pump, a cylindrical rotating body is disposed inside the sleeve, and a spiral groove is formed on the outer circumferential surface of the rotating body.By rotationally driving the rotating body, the outer circumferential surface of the rotating body and the sleeve The fluid trapped between two adjacent windings of the blade is transferred from one end of the sleeve to the other end of the sleeve. In other words, the screw pump described above only transfers fluid from one end to the other, and does not have the function of compressing fluid.

(Problems to be Solved by the Invention) As described above, the conventional fluid compressor has a complicated structure, has a long axial length, and has a large number of parts. Furthermore, gas sometimes leaked from the check valve provided at the boundary between the high pressure side and the low pressure side, resulting in low compression efficiency. Further, a type of screw pump in which a rotating body wrapped with spiral blades is disposed within a sleeve simply transports fluid and does not have a compression effect.

This invention was made based on the above circumstances, and its purpose is to improve sealing performance and achieve efficient compression with a relatively simple structure, and to facilitate the manufacture and assembly of parts. The object of the present invention is to provide a fluid compressor that can be downsized.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above problems, the present invention includes an electric element consisting of a stator and a rotor, and a suction end held concentrically with the rotor of the SO main. A cylinder having a side and a discharge end side, and is arranged eccentrically within this cylinder along the axial direction of the cylinder, and is rotatable relative to the cylinder with a part of the cylinder in contact with the inner circumferential surface of the cylinder. A cylindrical rotating body, a spiral groove formed on the outer periphery of the rotating body with a pitch that gradually decreases from the suction end side to the discharge end side of the cylinder, and a spiral groove that is inserted into and out of the groove freely. a spiral blade having an outer circumferential surface in close contact with an inner circumferential surface of the cylinder and dividing a space between the inner circumferential surface of the cylinder and the outer circumferential surface of the rotary body into a plurality of working chambers; and a mechanism for rotating a body in synchronization with the cylinder to sequentially transfer fluid flowing into the working chamber from the suction end side of the cylinder to the working chamber on the discharge side of the cylinder.

(Function) By doing so, the present invention has a simple structure that allows for smooth operation, improved sealing performance, and efficient compression.Furthermore, it is possible to easily manufacture and assemble parts, and to reduce the size of the parts. It's because I did it.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a hermetic compressor 1 for refrigerant gas used in a refrigeration cycle. A compression element 4 is provided. The electric element 3 has a substantially annular stator 5 fixed to the inner surface of the sealed case 2 and an annular rotor 6 provided inside the stator 5.

The compression element 4 has a cylinder 7, and the rotor 6 is coaxially fixed to the outer peripheral surface of the cylinder 7. Both ends of the cylinder 7 are rotatably supported by bearings 8.9 fixed to the inner surface of the sealed case 2, and both ends of the cylinder 7 are hermetically closed by these bearings 8.9. That is, the bearings 8.9 have boss portions 8a, 9a into which the ends of the cylinder 7 are rotatably fitted.
and base portions 8b, 9b which have a larger diameter than the boss portions 8a, 9a and are fixed to the inner surface of the sealed case 2.

Inside the cylinder 7, a piston 11, which is a cylindrical rotating body having an outer diameter smaller than the inner diameter of the cylinder 7, is disposed along the axial direction of the cylinder 7. This piston 1
1, the central axis A of the piston 11 is eccentrically arranged downward by a distance Ate with respect to the central axis B of the cylinder 7 in FIG. is in contact with the surface.

Support shaft portions 1 are provided at both axial ends of the piston 11, respectively.
2a, 12b are provided, and these support shafts 12a, 12b
are bearing holes 8c and 9 formed in the bearings 8 and 9, respectively.
It is rotatably inserted and supported in c.

A prismatic portion 13 having a square cross section is formed on one support shaft portion 12a of the piston 11. As shown in FIG. As shown in FIG. 4, this prismatic portion 13 is provided with an Oldham ring 15 in which a rectangular long hole 14 is bored. In other words, the prismatic portion 13
An Oldham ring 15 is fitted into the elongated hole 14 so as to be slidable along the longitudinal direction thereof. One end portion of a pair of pins 16 is slidably inserted into the outer periphery of the Oldham ring 15 in a radial direction perpendicular to the longitudinal direction of the elongated hole 14, respectively. The other ends of these bottles 16 are fitted and fixed into fitting holes 17 bored in the peripheral wall of the cylinder 7.

Therefore, the upper = own piston 11 is connected to the cylinder 7,
It is coupled eccentrically with respect to the radial direction of the cylinder 7. However, now it's time for the electric element 3! ! When the cylinder 7 and rotor 6 are rotated together with one electric current, the rotational force of the cylinder 7 is transmitted to the piston 11 via the Oldham ring 15. Note that the fitting hole 17 is hermetically closed by a cover member 18. Then, the piston 11 internally rotates within the cylinder 7 with a portion of the piston 11 in contact with the inner surface of the cylinder 7.

The outer circumferential surface of the piston 11 has a spiral shape 19 along the axial direction of the piston 11, as shown in FIGS. 1 to 3.
is formed. The pitch of the grooves 19 is gradually reduced from the right side to the left side in these drawings, that is, from the suction side to the discharge side of the cylinder 7.

A spiral blade 21 shown in FIGS. 2 and 3 is fitted into the groove 19. The thickness of the blade 21 substantially matches the width of the spiral groove 13 = j method, and each part of the blade 21 can freely move forward and backward relative to the groove 19 in approximately the radial direction of the piston 11. The blade 21
The outer circumferential surface of the cylinder 7 is in close contact with the inner circumferential surface of the cylinder 7, and it slides on the inner circumferential surface of the cylinder 7 in this state.

The space between the inner circumferential surface of the cylinder 7 and the outer circumferential surface of the piston 11 is formed by the blade 21 into a plurality of working chambers 22.
It is divided into In other words, each working chamber 22 has a blade 2
1 is formed between two adjacent windings of the cylinder 7, and extends along the blade 21 from the contact point between the piston 11 and the inner circumferential surface of the cylinder 7 to the next contact point, forming an approximately three-month shape. There is.

The volume of the working chamber 22 gradually decreases from the suction side to the discharge side of the cylinder 7.

One of the bearings 8 located on the suction side of the upper J and the cylinder 7 has a suction hole 23 passing therethrough in the axial direction, as shown in FIG. One end of this suction hole 23 communicates with the inside of the cylinder 7, and the other end is connected to a suction tube 24 of the refrigeration cycle.A discharge hole 25 is also bored in the other bearing 9. One end of the discharge hole 25 communicates with the discharge end side inside the cylinder 7, and the other end opens into the inside of the sealed case 2.

The piston 11 has an oil introduction passage 26 as shown in FIG.
is bored along its central axis A.

One end of this oil introduction path 26 communicates with the bottom of the spiral groove 19 on the discharge side, and the other end communicates with a through hole 27 bored in one of the bearings 8.
It is connected to one end of the. The other end of this through hole 27 is connected to the other end of an introduction pipe 28 whose one end is located at the bottom of the sealed case 2 . 711 on the bottom of sealed case 2? N oil 29 is stored. Therefore, if the pressure inside the sealed container 2 increases, the lubricating oil 29 will flow into the introduction pipe 28.
The oil is introduced into the space between the bottom of the groove 19 and the blade 21 through the through hole 27 and the oil introduction path 26.

Further, a suction groove 31 is formed on the outer circumferential surface of the end of the piston 11 located on the suction side. This inhalation iR31
is formed deeper than the spiral shape 19 formed on the outer peripheral surface of the piston 11, one end of which is open to the end surface of the large diameter portion 11a of the piston 11, and the other end is located on the suction end side of the cylinder 7. It is located in a position communicating with the first working chamber 22. As a result, the cold tofu gas sucked into the cylinder 7 from the suction tube 24 passes through the suction groove 31 and into the cylinder 7.
This ensures that the liquid is introduced into the second working chamber 22 without interruption.

Note that, as shown in FIG. 1, a discharge tube 32 is connected to the sealed case 2 to communicate the inside and outside thereof.

Next, the operation of the compressor configured as above will be explained.

First, when the electric element 3 is energized, the rotor 6 rotates, and the cylinder 7 also rotates together with the rotor 6. cylinder 7
When the piston 11 rotates, the piston 11 is driven to rotate with a part of its outer circumferential surface in contact with the inner circumferential surface of the cylinder 7 . Such relative rotational movement between the piston 11 and the cylinder 7 is ensured by the Oldham ring 15 provided on the prismatic portion 13 of the piston 11. And blade 21
The piston 11 also rotates integrally with the piston 11.

Since the blade 21 rotates with its outer peripheral surface in contact with the inner peripheral surface of the cylinder 7, each part of the blade 21 is
As it approaches the contact area between the outer circumferential surface of the piston 11 and the inner circumferential surface of the cylinder 7, it is pushed into the X 19, and as it moves away from the contact area, it moves in the direction of protruding from the groove 19.

On the other hand, when the compression element 4 is activated, refrigerant gas is sucked into the cylinder 7 through the suction tube 24 and the suction hole 23. As shown in FIG. 6, the refrigerant gas sucked into the working chamber 22 of No. 1"j is trapped there, and as the piston 11 rotates with its lip, it is
As shown in the figure, they are sequentially transferred to the working chamber 22 on the discharge side.

Then, the transferred and compressed refrigerant gas is discharged from the discharge hole 25 formed in the discharge side bearing 9 into the space inside the sealed case 2, and is returned to the refrigeration cycle through the discharge tube 32.

When the refrigerant gas is discharged into the sealed case 2 and the pressure inside the sealed case 2 increases, the +1! ! The lubricating oil 29 is pressurized, and the lubricating oil 29 flows through the oil introduction path 26.
It is introduced into the space between the bottom of the spiral groove 19 and the blade 21 through the groove. Therefore, the blade 2 is always pressed in the direction of the direction in which it is pushed out of the groove 19 by hydraulic pressure, that is, toward the inner circumferential surface of the cylinder 7. Therefore, the outer circumferential surface of the blade 21 is always kept tightly shielded from the inner circumferential surface of the cylinder 7, which prevents gas from leaking between the working chambers 22.

Further, the spiral groove 19 formed on the piston 11 is formed such that the pitch thereof gradually decreases from the suction side to the discharge side of the cylinder 7.

In other words, the working chamber 22 partitioned by the blade 21 is formed so that its volume gradually decreases toward the discharge side. Therefore, while the refrigerant gas is transferred from the suction side to the discharge side of the cylinder 7, this refrigerant gas can be compressed. Further, since the refrigerant gas is transferred and compressed while being confined within the working chamber 22, the refrigerant gas can be efficiently compressed even if no check valve is provided on the discharge side of the compressor.

Furthermore, since the check valve can be omitted, the configuration of the compressor can be simplified and the number of parts can be reduced. In addition, since the rotor 6 of the electric motor lA3 is supported by the cylinder 7 of the compression element 4, there is no need to provide a dedicated rotating shaft or bearing for supporting the rotor 6. Therefore, the configuration of the compressor can be further simplified and the number of parts can be reduced.

Further, the rotor 6 of the electric element 3 was fixed concentrically to the outer peripheral surface of the cylinder 7 of the compression element 4. That is, since the cylinder is fitted and held inside the rotor 6, the overall axial length can be significantly shortened compared to the case where the electric element 3 and the compression element 3 are connected in series. Thereby, compression a
ll can be made smaller.

Note that iron-based metals are effective for the material of the piston 11;
If workability and weight reduction are important, aluminum-containing metal or resin may be used.

In addition, the grooves of the piston 11 are generally formed by cutting, but cutouts with a rectangular cross section are punched out from a disk and the cutouts are stacked 81 so that they form a spiral groove. Good too.

[Effects of the Invention] As described above, the present invention has a spiral groove in which the pitch gradually changes from one end to the other end on the outer periphery, and a spiral blade can be moved in and out of this groove. The fitted cylindrical rotating body is eccentrically arranged inside the cylinder, and the space between the inner peripheral surface of the cylinder and the outer periphery of the rotating body is divided into a plurality of working chambers by the blades, and the cylinder is electrically operated. The cylinder is held concentrically with the rotor of the element, and the cylinder and rotating body are rotated in unison to compress the fluid flowing into the working chamber from the suction side of the cylinder while sequentially transferring it to the working chamber on the discharge side of the cylinder. I decided to do so.

Therefore, according to the present invention, it is possible to operate smoothly with a simple structure, improve sealing performance and reliability, compress efficiently, and reduce the size of the container when manufacturing and assembling parts. It has the effect of

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a longitudinal sectional view showing the entire fluid compressor, Fig. 2 is an exploded view of the compression element, and Fig. 3 is a longitudinal sectional view showing the entire fluid compressor.
The figure is a perspective view of the piston, Figure 4 is a cross-sectional view of the connection part between the piston and cylinder by an Oldham ring, Figures 5 to 9 are explanatory diagrams sequentially showing the compression process of refrigerant gas, Figure 1
Figure 0 is a side view of the compression element. 2... Sealed case, 3... Electric element, 6... Rotor, 7... Cylinder, 11... Piston (rotating body)
15...Oldham ring, 19...groove, 21...
Blade, 22... working chamber. Applicant's agent Patent attorney Takehiko Suzue 12b Figure 3 @ Figure 4 g Figure 6 Figure 7

Claims (1)

[Claims] an electric element consisting of a stator and a rotor; a cylinder having a suction end side and a discharge end side held concentrically with the rotor of the electric element; , a cylindrical rotating body that can rotate relative to the cylinder with a part of it in contact with the inner circumferential surface of the cylinder, and a rotating body provided on the outer periphery of the rotating body from the suction end side to the discharge end side of the cylinder. a spiral groove formed at a pitch that gradually decreases, and an outer circumferential surface that is fitted into the groove so as to be able to move in and out and is in close contact with the inner circumferential surface of the cylinder, and the inner circumferential surface of the cylinder and the rotating body. a spiral blade that divides a space between the outer circumferential surface of the cylinder and the cylinder into a plurality of working chambers; A fluid compressor characterized by comprising a mechanism for sequentially transferring the fluid to a side working chamber.