JPH02201087A - Fluid compressor - Google Patents

Abstract

PURPOSE:To facilitate installation of a blade into a fluid compressor, in which a rotor with a spiral blade fitted on a spiral groove formed at the periphery is fitted in a cylinder, by dividing the blade into a plurality of divisions, and putting tapered surfaces one over another provided at the ends of these divisions. 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 side gradually toward the discharge side, and a spiral blade 21 is fitted in this groove 19 in such a way that it can advance and retreat freely. Therein the blade 21 is composed of a plurality of divisional blades 21a-21c, which are provided with tapered surfaces 20 at their ends, and these tapered surfaces 20 of adjoining blades are put one over another in the axial direction of the piston 11.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a fluid pressure tIIi machine that compresses refrigerant gas in a refrigeration cycle, for example, and particularly to a helical blade type fluid compressor.

(Prior Art) Conventionally, compressors of various types, such as reciprocating type and rotary type, have been known. 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 easily leaks and compression efficiency is low.

On the other hand, there is a helical blade type compressor that does not have the above problems. FIG. 15 shows the main parts of a conventional helical blade type fluid compressor, which includes a cylinder a, and an eccentric arrangement inside the cylinder a (e in the figure indicates the amount of eccentricity). A rotating body that makes a rotational movement (eccentric rotational movement) relative to the cylinder a,
The rotating body has a blade d inserted into a groove C formed in a spiral shape on the outer surface of the rotating body. As shown in FIG. 16, the blade d consists of a single structure with at least two turns and an unequal pitch spiral structure. slide in and out in the depth direction.

Both ends of the cylinder a and the rotating body are bearings f and g.
Each of the bearings f and g is provided with a suction port and a discharge port j, respectively. The pitch of the grooves C gradually narrows from the suction port 60h toward the discharge port j.

Therefore, when the cylinder a and the rotating body are caused to rotate relative to each other, the fluid to be compressed, such as gas, sucked into the space between the cylinder a and the rotating body from the suction port is compressed. That is, the above space is moved toward the discharge port j with the rotational movement of the rotating body relative to the cylinder a, but the above? As the pitch of Fi C gradually decreases, the volume of the space partitioned by the blades d gradually decreases. Therefore, the fluid to be compressed that enters the space is gradually compressed, and the final It is discharged from the discharge port j.

In a fluid compressor with such a conventional structure, the blade d reciprocates in the depth direction of the groove C with the relative rotational motion between the cylinder a and the rotating body, and at the same time, the blade d moves on both sides of each part of the blade d. Due to the difference in the applied pressure, the cylinder a receives a force in a helical direction along the groove C. Since the blade d is reciprocated along the helical direction due to such force, a large 777 # IM is generated between the cylinder a and the blade d due to such movement.
cause loss.

In addition, since the conventional blade d has a helical structure with at least two turns, it is troublesome to fit it into the groove C of the rotating body. Because of its pitched spiral structure, its manufacture was also troublesome.

(Problems to be Solved by the Invention) As mentioned above, in the conventional helical blade type fluid compressor, the blades attached to the rotating body have a helical structure with at least two turns and an uneven pitch. There was a problem in that a large sliding JM loss occurred between the blade and the cylinder, and the assemblability and manufacturability of the blade were poor.

An object of the present invention is to provide a fluid compressor that can reduce sliding loss between blades and cylinders, and improve assemblability and blade manufacturability.

[Structure of the Invention] (Means for Solving the Problem) In order to achieve the above object, the present invention provides a cylinder that is arranged eccentrically along the axial direction of the cylinder,
A spiral shaped member is fitted into a spiral groove with an uneven pitch provided on the outer periphery of a cylindrical rotating body that can rotate relative to the cylinder while a part of the rotating body is in contact with the inner circumferential surface of the cylinder. The blade is formed of a plurality of divided blades, and tapered surfaces formed at the ends of adjacent divided blades are overlapped in the axial direction of the rotating body.

(Function) In the helical blade type fluid compressor of the present invention, the blade is moved against the cylinder due to the pressure difference that acts on both sides of each part of the blade due to the relative rotational movement (eccentric rotational movement) between the cylinder and the rotating body. There is no change in the fact that it receives a force in a helical direction along the groove. However, since the pressure in each working chamber partitioned by the blade gradually increases from the suction end to the discharge end, the helical force exerted by each working chamber on the blade also increases for each working chamber. Different. Since the blade is formed of divided blades that partition each working chamber, the moving forces in the helical direction applied to these divided blades are also different. That is, the closer the divided blades are to the suction end, the smaller the moving force in the helical direction is applied, and conversely, the closer the divided blades are to the discharge end, the larger the moving force in the helical direction is applied. Therefore, relatively speaking, the moving distance of the split blade on the suction end side in the helical direction is smaller than the moving distance of the split blade on the discharge end side. As a result, the tapered end of the split blade on the discharge end side fits between the tapered end of the blade on the suction end side and the side surface of the groove on the discharge end side. Therefore, the tapered ends of adjacent split blades create a wedge effect with each other within the groove, thereby suppressing movement of the entire blade in the helical direction. Furthermore, since the number of turns of the split blade is small, it can be easily fitted into the groove of the rotating body, and these split blades can also be easily manufactured.

(Embodiment) An embodiment of the present invention will now be described with reference to FIGS. FIG. 7 shows a hermetic compressor 1 for refrigerant gas used in a refrigeration cycle.

The compressor 1 includes a closed case 2, and an electric element 3 and a compression element 4 as driving means arranged inside the closed case 2. The electric element 3 is in a closed case 2
The stator 5 has a substantially annular stator 5 fixed to the inner surface of the stator 5, and an annular rotor 6 provided inside the stator 5.

As shown in FIG. 1.7, the compression element 4 forms 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 bearing 8.9 has boss portions 8a and 9a into which the ends of the cylinder 7 are rotatably fitted, and a base portion having a diameter larger than the boss portions 88% and 9a and fixed to the inner surface of the sealed case 2. 8
b, 9b.

Inside the cylinder 7, a piston 11 as 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. The piston 11 is made of iron or other material, and its central axis A is eccentrically disposed downward in FIGS. 1 and 7 by a distance 11ie relative to the central axis B of the cylinder 7. A portion of the outer peripheral surface of the piston 11 is in line contact with the inner peripheral surface of the cylinder 7.

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

A prismatic portion 13 having a square cross section is formed on one of the support shaft portions 12a of the piston 11, as roughly shown in FIG. 5.6. As shown in FIG. 6, this prismatic portion 13 is provided with an Oldham ring 15 in which a rectangular long hole 14 is bored. In other words, the Oldham ring 15 is attached to the prismatic portion 13.
is slidably fitted along the longitudinal direction of the elongated hole 14. A pair of bins 1 are provided on the outer peripheral surface of the Oldham ring 15 in a radial direction perpendicular to the longitudinal direction of the elongated hole 14.
6 are slidably inserted into each other.

The other ends of these pins 16 are fitted and fixed into fitting holes 17 formed in the peripheral wall of the cylinder 7.

As a result, the earthworker's piston 11 moves to the cylinder 7,
The cylinder 7 is connected to an eccentric member 7E in the radial direction. Therefore, when the electric element 3 is energized and the cylinder 7 and rotor 6 are rotated together, 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.

A spiral groove 19 is formed on the outer peripheral surface of the piston 11 along the axial direction of the piston 11, as shown in FIGS. 7 and 8, respectively. 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 end side to the discharge end side of the cylinder 7.

Top 2? M19 has a plate 21 that has a spiral shape as a whole.
is embedded. This blade 21 is made of synthetic resin or other material, and both ends thereof are connected to the piston 1.
1 in a plane substantially perpendicular to the bottom. Further, the thickness of the blade 21 is approximately the same as the width of the spiral groove 19, and the 6th part of the blade 21 is in the groove 19.
The piston] 1 can freely move forward and backward in the radial direction. The outer circumferential surface of the blade 21 is in close contact with the inner circumferential surface of the cylinder 7, and slides on the inner circumferential surface of the cylinder 7 in this state.

The blade 21 is formed of a plurality of divided blades 218 to 21c as shown in FIGS. 1 and 2. These divided blades 21a to 21C are arranged so that at least one working chamber 22, which will be described later, can be formed by itself.
It can be wound more than one turn, and in this embodiment it is one and a half turns. Moreover, a tapered surface 20 is formed at the end of each of the adjacent divided blades 213 to 21c.

The respective tapered surfaces 20 are provided, for example, substantially over the earth's circumference, and are overlapped with each other in the axial direction of the piston 11. In other words, the tapered surfaces 20 of the adjacent divided blades 21a to 21c are connected to the adjacent working chambers 20 as shown in FIG.
In a comradely relationship, the tapered end portion having the tapered surface of the divided blade provided to partition the high-pressure P22 portion movement chamber is arranged so as to face the high-pressure P22 portion movement chamber,
Low pressure P, the tapered end of the split blade provided to partition the side working chamber with the tapered surface 20,
By arranging them facing the side working chambers, they are superimposed on each other in the axial direction of the piston 11.

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 That is, each working chamber 22 is formed between two adjacent windings of the blade 21, and extends along the blade 21 from the contact point between the piston 11 and the inner peripheral surface of the cylinder 7 to the next contact point. It is crescent-shaped.

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

As shown in FIG. 7, one of the bearings 8 located on the suction end side of the cylinder 7 has a suction hole 23 passing through it in the axial direction. One end of this suction hole 23 communicates with the inside of the cylinder 7,
A suction tube 24 of a refrigeration cycle is connected to the other end. Further, the other bearing 9 is provided with a discharge hole 25 . One end of this 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 auxiliary 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 . Lubricating oil 29 is placed at the bottom of the sealed case 2.
is stored. Therefore, when the pressure inside the sealed case 2 increases, the two lubricating oils are introduced into the space between the bottom of the upper two grooves 19 and the blade 21 through the introduction pipe 28, the through hole 27 and the auxiliary introduction passage 26. be done.

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 suction groove 31 is formed deeper than the spiral groove 19 formed on the outer peripheral surface of the piston 11, and one end thereof is open to the end surface of the large diameter portion 11a of the piston 11, and the other end is a suction groove of the cylinder 7. It is located in a position communicating with the eleventh working chamber 22 located on the end side. Thereby, the refrigerant gas sucked into the cylinder 7 from the suction tube 24 is reliably introduced into the first working chamber 22 through the suction groove 31 without interruption.

Note that a discharge tube 32 is connected to the sealed case 2, as shown in FIG. 7, for communicating the inside and outside of the case.

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 76 rotates together with the rotor 6.

When the cylinder 7 rotates, the piston 11 is driven to rotate with a portion of its outer circumferential surface in contact with the inner circumferential surface of the cylinder 7 . Note that, as shown by the arrow in FIG. 14, the rotation direction of the cylinder 7 and the piston 11 is clockwise when viewed from the suction end side. Piston 11 and cylinder 7 like this
The 1'1 rotational movement (eccentric rotational movement) is caused by the Oldham ring 1 provided on the prismatic portion 13 of the piston 11.
5. The blade 21 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 groove 19, and as it moves away from the contact area, it moves in the direction of protruding from the groove 19.

Due to the operation of the compression element 4 as described above, the suction tube 2
Cold tofu gas is sucked into the cylinder 7 through the cylinder 4 and the suction hole 23. As shown in FIG. 9, the refrigerant gas sucked into the working chamber 22 of No. 1 1:J is trapped there as the piston 11 rotates, as shown in FIGS. 10 to 13. The liquid is sequentially transferred to the working chamber 22 on the discharge end side. The transferred and compressed refrigerant gas is then discharged into the space inside the sealed case 2 from the discharge hole 25 formed in the bearing 9 on the discharge end side, and is returned to the refrigeration cycle through the discharge tube 32.

Incidentally, the spiral grooves 19 formed in the piston 11 are formed such that the pitch thereof gradually decreases from the suction end side to the discharge end 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 end side.

Therefore, while the refrigerant gas is transferred from the suction end side to the discharge end side of the cylinder 7, this refrigerant gas can be compressed. Moreover, since the cold tofu gas is transferred and compressed while being confined within the working chamber 22, the refrigerant gas can be efficiently compressed without providing a check valve on the discharge side of the compressor.

When the compressed refrigerant gas is discharged into the sealed case 2 and the pressure inside the sealed case 2 increases, the lubricating oil 29 stored inside is pressurized, and the lubricating oil 29 passes through the oil introduction path 26 and spirals. The blade 21 is introduced into the space between the bottom of the shaped groove 19 and the blade 21. Therefore, the blade 21 is moved in the direction in which it is pushed out from the groove 19 by hydraulic pressure, that is, in the direction in which the blade 21 is pushed out from the groove 19 by the hydraulic pressure.
1. It is always pressed towards the first side. therefore,
The outer circumferential surface of the blade 21 is always kept in close contact with the inner circumferential surface of the cylinder 7, which prevents gas from leaking between the working chambers 22.

On the other hand, in the above-mentioned operation of the compression element 1A4, the blade 21 is
Friction between the outer circumferential surface of the cylinder 7 and the inner circumferential surface of the cylinder 7 and the pressure difference between the adjacent working chambers 22 (in FIG. 3.4, p, , p2 indicate the gas pressure in the adjacent working chambers, and Pl is F2. ) by
The blade 21 receives a force in a helical direction along the groove 19 against the cylinder 7 .

However, since the blade 21 is formed of a plurality of divided blades 21a to 21c that partition each working chamber 22, the moving force in the helical direction (arrow F l r in Fig. 3.4) applied to these divided blades 21a to 2IC Indicated by F2.

) are also different. In this way, the moving force in the spiral direction FI+F
Based on the difference between The moving distance ΔXC that the splitting blade (for example, the splitting blade indicated by reference numeral 21c) moves due to the helical moving force F2 applied thereto increases.

Due to such a difference in moving distance, the tapered end of the split blade 21c on the discharge end side becomes closer to the split blade 21 on the suction end side.
b and the side surface of the discharge end side of the groove 19 (the fourth
(indicated by reference numeral 19a in the figure). Thereby, adjacent split blades 21b, 21 in the groove 19
C creates a wedge effect at its tapered end. In addition,
Such an effect is caused by the adjacent split blades 21a, 21b.
It is also done between.

Therefore, the blade 21 body is restrained from moving along the helical direction using the groove as a guide, and the blade 21 as a whole hardly moves 1n relative to the cylinder 7.

Therefore, the sliding loss between the blade 21 body and the cylinder 7 can be reduced, and efficiency can be improved.

Also, as mentioned above, Blade 21! Instead of a spiral structure, a plurality of divided blades 21a to 21 (with 113
According to this configuration, since the number of turns of each of the divided plates 213 to 21C is small, these parts can be fitted into 8 parts compared to 19 parts of the piston 11, and productivity can be improved. In addition, these divided blades 21a to 21c can be easily manufactured.

In addition, since the check valve can be omitted in this compressor, it is possible to simplify the construction of the compressor and reduce the number of parts. Furthermore, since the rotor 6 of the electric element 3 is supported by the cylinder 7 of the compression element 4, the rotor 6
There is no need to provide a dedicated rotating shaft or bearing to support the system. Therefore, it goes without saying that the configuration of the compressor can be further simplified and the number of parts can be reduced.

[Effects of the Invention] As described above, the present invention provides a spiral blade that is fitted in and out of a spiral groove provided on the outer periphery of a cylinder and a rotating body that is inscribed therein and rotates relative to the cylinder. , is formed from a plurality of divided blades, and the tapered surfaces formed at the ends of adjacent divided blades are overlapped in the axial direction of the rotating body, so that the axial sliding of the blades with respect to the cylinder is suppressed, Jff movement between these 1
It is possible to reduce i loss, facilitate the work of fitting the blade into the groove of the rotating body, and improve the manufacturability of the blade itself.

[Brief explanation of the drawing]

Figures 1 to 14 show a first embodiment of the present invention.
The figure is a cross-sectional view of the compression element, Figure 2 is an exploded side view of the blade, Figure 3 is an enlarged cross-sectional view of a part of the compression element, and Figure 4 is the action at the joint between the split blades. Fig. 5 is a perspective view of the piston with a blade attached, Fig. 6 is a cross-sectional view of the connection between the piston and cylinder by the Oldham ring, and Fig. 7 is a vertical cross-section showing the entire fluid compressor. 8 is an exploded view of the compression element, FIGS. 9 to 13 are explanatory diagrams sequentially showing the refrigerant gas compression process, and FIG.
Figure 4 is a side view of the compression element; FIG. 15 is a sectional view of a compression element in a conventional helical blade type compressor, and FIG. 16 is a side view of a blade used in the compression element shown in FIG. 15. 3... Electric element (driving means), 7... Cylinder, 1
1... Piston (rotating body) 15... Oldham ring, 19... Groove, 20... Tapered surface, 21...
Blades, 21a to 21c... split blades, 22.
...Working room. Figure 3 Applicant's agent Patent attorney Takehiko Kataura Figure 4 Figure 4 Figure 4 Figure Figure 4 Figure Figure Figure Figure Figure Figure

Claims (1)

[Claims] A cylinder having a suction end side and a discharge end side, and a cylinder disposed eccentrically along the axial direction of the cylinder within this cylinder, with a part of the cylinder in contact with the inner circumferential surface of the cylinder, and relative to the cylinder. A rotatable cylindrical rotating body,
A spiral groove is provided on the outer periphery of the rotating body and is formed at a pitch that gradually decreases from the suction end side to the discharge end side of the cylinder, and a spiral groove is fitted into the groove so as to be able to move in and out. a spiral blade having an outer circumferential surface in close contact with the cylinder and dividing a space between the inner circumferential surface of the cylinder and the outer circumferential surface of the rotating body into a plurality of working chambers, and rotating the rotating body synchronously with the cylinder; In a fluid compressor equipped with a mechanism for sequentially transferring fluid flowing into the working chamber from the suction end side of the cylinder to the working chamber on the discharge end side of the cylinder, the blade is formed of a plurality of divided blades, A fluid compressor characterized in that tapered surfaces formed at the ends of adjacent divided blades are overlapped in the axial direction of the rotating body.