JP2859279B2 - Fluid compressor - Google Patents

Description

The present invention relates to a fluid compressor for compressing a refrigerant gas of a refrigeration cycle, for example, and more particularly to a helical blade type fluid compressor.

(Prior Art) Conventionally, various compressors such as a reciprocating compressor and a rotary compressor have been known. However, in these compressors, the structure of a drive unit such as a crankshaft for transmitting the rotational force to the compressor unit and the compressor unit is complicated, and the number of parts is large. Further, in such a conventional compressor, it is necessary to provide a check valve on the discharge side in order to increase the compression efficiency. However, since the pressure difference between the two sides of the check valve is very large, Gas leaks easily and compression efficiency is low. In order to solve such a problem, it is necessary to increase the dimensional accuracy and assembling accuracy of each component, but this increases the manufacturing cost.

Further, U.S. Pat. No. 2,401,189 discloses a screw pump. According to this pump, a cylindrical rotating body is disposed in the sleeve, and a spiral groove is formed on the outer peripheral surface of the rotating body. A spiral blade is slidably fitted in this groove. And
By rotating the rotating body, the fluid trapped between two adjacent turns of the blade between the outer circumferential surface of the rotating body and the inner circumferential surface of the sleeve is transferred from one end of the sleeve to the other end. . That is, the above-described screw pump merely transfers the fluid from one end to the other end, and does not have a function of compressing the fluid.

(Problems to be Solved by the Invention) As described above, the conventional fluid compressor has a complicated structure and a large number of parts. Further, gas may leak from a check valve provided at a boundary between the high pressure side and the low pressure side, and the compression efficiency is low. Further, a screw pump of a type in which a rotating body wound with a helical blade is arranged in a sleeve simply transfers fluid, and has no compressing action.

The present invention has been made based on the above circumstances, and aims to compress a fluid to be compressed by a relatively simple structure, to easily manufacture and assemble parts, and to reduce the passage resistance of the fluid to be compressed. It is to obtain a small fluid compressor.

[Means for Solving the Problems] To achieve the above object, the present invention provides a cylinder,
A cylindrical rotating body which is disposed eccentrically along the axial direction of the cylinder and is rotatable relative to the cylinder with a part of the outer peripheral surface being in contact with the inner peripheral surface of the cylinder; A helical groove provided on the outer peripheral surface of the rotating body and formed at a pitch that gradually decreases from the suction side to the discharge side of the cylinder; A helical blade having an outer peripheral surface to partition the space between the inner peripheral surface of the cylinder and the outer peripheral surface of the rotating body into a plurality of working chambers, and at the suction end side and the discharge end side The suction hole and the discharge hole communicating with the located working chamber are located on the side opposite to the eccentric direction of the rotating body, and are opposed to the widest part of the width of the crescent-shaped space in the working chamber from the axial direction. Also provided It is.

(Operation) In the fluid compressor of the present invention, since the cylinder and the rotating body eccentrically inscribed therein are relatively swirled, the blade enters and exits the spiral groove.
Since the pitch of the blades and grooves is gradually reduced from the suction end side to the discharge end side, and therefore the volume of the working chamber is also gradually reduced in the same direction, the cylinder and the rotating body are Fluid to be compressed such as gas sucked in between can be compressed while being transferred from the suction end side to the discharge end side of the cylinder in a state of being confined in the working chamber. Therefore, the check valve can be dispensed with.

Further, in this fluid compressor, since the rotating body is eccentric with respect to the cylinder, the working chamber formed therebetween has a substantially crescent shape. Under such conditions,
The suction hole and the discharge hole communicating with the working chambers located on the suction end side and the discharge end side are located on the side opposite to the eccentric direction of the rotating body with respect to the center of the cylinder, and the width of the crescent-shaped space in the working chamber Are provided so as to face each other from the axial direction at the widest part. For this reason, even when the amount of eccentricity is reduced, the suction hole and the discharge hole are less likely to be hidden by the end of the rotating body. Therefore, the fluid to be compressed smoothly flows into the working chamber from the suction hole and smoothly flows out from the working chamber to the discharge hole.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a hermetic compressor 1 for a 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 disposed in the closed case 2. The electric element 3 includes a substantially annular stator 5 fixed to the inner surface of the closed case 2 and an annular rotor 6 provided inside the stator 5.

As shown in FIGS. 1 and 4, 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 and 9 fixed to the inner surface of the sealed case 2. Both ends of the cylinder 7 are hermetically closed by these bearings 8 and 9. That is, the bearings 8 and 9 are composed of boss portions 8a and 9a in which the ends of the cylinder 7 are rotatably fitted, and a base portion which is larger in diameter than the boss portions 8a and 9a and is fixed to the inner surface of the sealed case 2. 8b and 9b.

In the cylinder 7, a piston 11 as a columnar 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 an iron-based or other material, and its central axis A is disposed eccentrically downward with respect to the central axis B of the cylinder 7 in FIG. Part of the outer peripheral surface of the piston 11 is in line contact with the inner peripheral surface of the cylinder 7.

A support portion 12 is provided at each end of the piston 11 in the axial direction.
a and 12b are provided, and these shaft portions 12a and 12b are rotatably inserted and supported in bearing holes 8c and 9c formed in the bearings 8 and 9, respectively.

As shown in FIGS. 5 and 6, a prism section 13 having a square cross section is formed on one support shaft section 12a of the piston 11.
As shown in FIG. 6, the prism 13 is provided with an orifice ring 15 having a rectangular elongated hole 14 formed therein. That is, the Oldham ring 15 is slidably fitted in the prism 13 along the longitudinal direction of the long hole 14. One end of a pair of pins 16 is slidably fitted on the outer peripheral surface of the Oldham ring 15 in a radial direction orthogonal to the longitudinal direction of the long hole 14. The other ends of the pins 16 are fitted and fixed in fitting holes 17 formed in the peripheral wall of the cylinder 7.

Thereby, the piston 11 is connected to the cylinder 7 eccentrically in the radial direction of the cylinder 7. Therefore, the electric element 3 is energized to
When the rotor 6 and the rotor 6 are integrally rotated, the rotational force of the cylinder 7 is transmitted to the piston 11 via the Oldham ring 15. The fitting hole 17 is hermetically closed by a cover member 18. And the piston
Numeral 11 turns with the eccentricity e as a radius in a state where a part of the cylinder 7 contacts the inner surface of the cylinder 7. Means for causing the relative rotation of the piston 11 with respect to the cylinder 7 is formed by the electric element 3, the rotor 6, the cylinder 7, the Oldham mechanism, and the like.

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. The pitch of the groove 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.

A spiral blade 21 is fitted in the groove 19. The blade 21 is made of a synthetic resin or other material, and both ends of the blade 21 are provided in a plane substantially perpendicular to the axis of the piston 11. Further, the thickness dimension of the blade 21 is substantially equal to the width dimension of the spiral groove 19, and each part of the blade 21 can freely advance and retreat in the radial direction of the piston 11 with respect to the groove 19. The outer peripheral surface of the blade 21 is in close contact with the inner peripheral surface of the cylinder 7 and slides on the inner peripheral surface of the cylinder 7 in this state.

The air between the inner peripheral surface of the cylinder 7 and the outer peripheral surface of the piston 11 is partitioned by the blade 21 into a plurality of working chambers 22. That is, each working chamber 22 is formed between two adjacent turns of the blade 21, and extends substantially from the contact portion between the piston 11 and the inner peripheral surface of the cylinder 7 along the blade 21 to the next contact portion. It has a crescent shape. The volume of the working chamber 22 gradually decreases as going from the suction side to the discharge side of the cylinder 7.

As shown in FIGS. 1 and 2, a suction hole 23 is axially penetrated through one of the bearings 8 located on the suction end side of the cylinder 7. The suction hole 23 is formed in the bearing 8 at a position opposite to the eccentric direction of the piston 11 with respect to the center of the cylinder 7, that is, above the line l-1 in FIG. One end of the suction hole 23 inserted into the cylinder 7 is connected to the widest part of the working chamber 22 on the discharge side (the width dimension of this part is indicated by w) as shown in FIG.
The other end is connected to the suction tube 24 of the refrigeration cycle as shown in FIG.

The other bearing 9 located on the discharge end side of the cylinder 7 is provided with a discharge hole 25 as shown in FIGS. The inlet side portion of the discharge hole 25 extends along the axial direction and on the side opposite to the eccentric direction of the piston 11 with respect to the center of the cylinder 7, that is, the line segment l in FIG.
The inlet end of the discharge hole 25, which is formed in the cylinder 7 and located above the -l, has the widest width of the suction-side working chamber 22, as shown in FIG. A portion (the width dimension of this portion is indicated by w) is opposed from the axial direction of the cylinder 7, and the other end is opened inside the closed case 2 as shown in FIG.

As shown in FIG. 1, an oil introduction passage 26 is formed in the piston 11 along the center axis A thereof. This oil introduction channel 26
Has one end communicating with the bottom of the spiral groove 19 on the discharge side, and the other end communicating with one end of a through hole 27 formed in one bearing 8. The other end of the through hole 27 is connected to the other end of the introduction pipe 28 whose one end is located at the bottom of the sealed case 2. A lubricating oil 29 is stored in the bottom of the closed case 2. Therefore, when the pressure in the sealed case 2 increases, the lubricating oil 29 is introduced into the space between the bottom of the groove 19 and the blade 21 through the introduction pipe 28, the through hole 27, and the oil introduction passage 26. .

Furthermore, a suction groove 31 is formed in the outer peripheral surface of the end located on the suction side of the piston 11. The suction groove 31 is formed deeper than the spiral groove 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 11 a of the piston 11, and the other end of which receives the suction of the cylinder 7. It is in a position communicating with the first working chamber 22 located on the end side. Thereby, the refrigerant gas sucked from the suction tube 24 into the cylinder 7 is surely introduced into the first working chamber 22 through the suction groove 31 without interruption.

As shown in FIG. 1, a discharge tube 32 that connects the inside and the outside of the closed case 2 is connected to the closed case 2.

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

First, when power is supplied to the electric element 3, the rotor 6 rotates, and the cylinder 7 also rotates integrally with the rotor 6. Cylinder 7
Is rotated, the piston 11 is driven to rotate with a part of its outer peripheral surface in contact with the inner peripheral surface of the cylinder 7. That is, using the eccentricity e as a radius, the piston 11
Is turned against. As shown by arrows in FIG. 12, the rotation directions of the cylinder 7 and the piston 11 are clockwise as viewed from the suction end side. Such a relative pivotal motion (eccentric rotational motion) between the piston 11 and the cylinder 7 is ensured by the Oldham ring 15 provided on the prism 13 of the piston 11. Then, the blade 21 also rotates integrally with the piston 11.

Since the blade 21 rotates with its outer peripheral surface being in contact with the inner peripheral surface of the cylinder 7, each part of the blade 21 moves toward the contact portion between the outer peripheral surface of the piston 11 and the inner peripheral surface of the cylinder 7. It is pushed into the groove 19 and moves in a direction protruding from the groove 19 as it moves away from the contact portion.

By the operation of the compression element 4 as described above, the suction tube
Refrigerant gas is sucked into the cylinder 7 through 24 and the suction hole 23. Then, as shown in FIG. 7, the first working chamber
The refrigerant gas sucked into the nozzle 22 is sequentially transferred to the working chamber 22 on the discharge end side as shown in FIGS. And
The transferred and compressed refrigerant gas is discharged into a space in the sealed case 2 from a discharge hole 25 formed in the bearing 9 on the discharge end side, and returned to the refrigeration cycle through a discharge tube 32.

By the way, the spiral groove 19 formed in the piston 11 is formed such that the pitch gradually decreases from the suction end side of the cylinder 7 toward the discharge end side. That is, the working chamber 22 partitioned by the blades 21 is formed such that the volume gradually decreases toward the discharge end side. Therefore, the refrigerant gas can be compressed during the transfer of the refrigerant gas from the suction end side to the discharge end side of the cylinder 7.
Further, since the refrigerant gas is transferred and compressed while being confined in the working chamber 22, the refrigerant gas can be efficiently compressed without providing a check valve on the discharge side of the compressor.

The compressed refrigerant gas is discharged into the closed case 2, and when the pressure inside the closed case 2 increases, the lubricating oil 29 stored inside is pressurized, and the lubricating oil 29 is supplied to the oil introduction passage 26.
Is introduced into the space between the bottom of the spiral groove 19 and the blade 21. Therefore, the blade 21 is hydraulically
, Ie, constantly pressed toward the inner peripheral surface of the cylinder 7. Therefore, the outer peripheral surface of the blade 21 is always kept in close contact with the inner peripheral surface of the cylinder 7, which prevents gas leakage between the working chambers 22.

In this compressor, since the check valve can be omitted as described above, the configuration of the compressor can be simplified and the number of parts can be reduced. The rotor 6 of the electric element 3
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, in this fluid compressor, the piston 11 is
12, the working chamber 22 formed therebetween has a substantially crescent shape as shown in FIG. This has already been mentioned. Then, under such conditions, the suction hole 23 and the discharge hole 25 communicating with the working chamber 22 located on the suction end side and the discharge end side.
Is located on the opposite side of the direction of the eccentricity of the piston 11 with respect to the center of the cylinder 7, and is provided so as to oppose the widest part of the crescent-shaped space in the working chamber 22 from the axial direction of the cylinder 7. Most of the open end faces of the suction hole 23 and the discharge hole 25 can be directly communicated with the crescent-shaped space.

Therefore, when the amount of eccentricity e is reduced (if not, the width of the blade 21 projecting from the groove 19 becomes large, and the blade 21 is caused by the differential pressure between the adjacent working chambers 22). The suction hole 23 and the discharge hole 25 are formed by the end face of the large-diameter portion 11a of the piston 11 even when the blade 21 is easily inclined to the suction side and an excessive force is applied to the blade 21 to reduce its durability and reliability. Hiding by 11b (see FIG. 4) can be minimized. That is, the resistance of the piston 11 to the passage resistance of the refrigerant gas can be minimized. For this reason, the refrigerant gas can smoothly flow into the working chamber 22 from the suction hole 23 and can flow smoothly from the working chamber 22 to the discharge hole 25.

In the present invention, a synchronous rotating means such as an Oldham ring part for relatively rotating the cylinder 7 and the piston 11 may be arranged on the discharge end side instead of the suction end side.
In this case, the passage resistance of the sucked compressed fluid can be further reduced.

[Effects of the Invention] As described above, the present invention provides a helical structure in which a rotating body is eccentrically provided and inscribed in a cylinder, and the pitch of which gradually changes from one end to the other end on the outer periphery of the rotating body. A spiral blade is inserted into this groove so that it can enter and exit freely, and the blade partitions the space between the cylinder and the rotating body into a plurality of working chambers, and the cylinder and the rotating body relatively rotate. Then, the fluid to be compressed flowing into the working chamber from the suction side of the cylinder is compressed while being sequentially transferred to the working chamber on the discharge side of the cylinder.

Therefore, according to the present invention, the fluid to be compressed can be compressed with a simple configuration, and the manufacture and assembly of parts can be facilitated.

Further, in the present invention, the suction hole and the discharge hole communicating with the working chambers located on the suction end side and the discharge end side of the cylinder are located on the opposite side to the eccentric direction of the rotating body with respect to the center of the cylinder. The crescent-shaped space is provided so as to oppose the widest part in the axial direction from the axial direction, so that the diameters of the suction hole and the discharge hole can be set to sufficiently large dimensions required for design, and the space for the working chamber can be reduced. The flow of the fluid to be compressed can be made smooth by reducing the resistance of the end of the rotating body from becoming a passage resistance when the compressed fluid enters and exits.

[Brief description of the drawings]

1 shows an embodiment of the present invention, FIG. 1 is a longitudinal sectional view showing the entire fluid compressor, FIG. 2 is a sectional view taken along the line II-II in FIG. 1, and FIG. FIG. 4 is an exploded view of the compression element, FIG. 5 is a perspective view of a piston with a blade attached, FIG. 6 is a cross-sectional view taken along the line VI-VI in FIG. 7 to 11 are explanatory diagrams sequentially showing the process of compressing the refrigerant gas, and FIG. 12 is a side view of the compression element. 3 ... Electric element (drive means), 7 ... Cylinder, 11 ...
Piston (rotating body), 15 ... Oldham ring, 19 ...
Groove, 21… Blade, 22… Working chamber, 23… Suction hole, 25
... discharge hole, e ... eccentric amount.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Makoto Hayano 8 Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Inside the Home Appliances Research Laboratory, Toshiba Yokohama Office Co., Ltd. (72) Inventor Hitoshi Hattori Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa No. 8 Toshiba Yokohama Office, Home Appliance Research Laboratory (72) Inventor Naoya Ryukaku 8 Shinsugita-cho, Isogo-ku, Yokohama, Kanagawa Prefecture Toshiba Yokohama Office, Home Appliance Research Laboratory (72) Inventor Toshikatsu Iida Kanagawa 70, Yanagicho, Yuki-ku, Kawasaki-shi In the Toshiba Yanagimachi Plant (56) References Japanese Utility Model Application Sho 61-51401 (JP, U) US Patent 2,527,536 (US, A) (58) Fields investigated (Int. Cl. ⁶⁾ , DB name) F04C 2/30-2/352 F04C 18/30-18/352

Claims (1)

(57) [Claims] 1. A cylinder, which is disposed eccentrically in the cylinder along the axial direction of the cylinder, and is relatively rotatable with a part of the outer peripheral surface being in contact with the inner peripheral surface of the cylinder. A cylindrical rotator, a spiral groove provided on the outer peripheral surface of the rotator and formed at a pitch that gradually decreases from the suction side to the discharge side of the cylinder; A helical blade that has an outer peripheral surface that is in close contact with the inner peripheral surface of the cylinder and that partitions a space between the inner peripheral surface of the cylinder and the outer peripheral surface of the rotating body into a plurality of working chambers; The suction hole and the discharge hole communicating with the working chamber located on the suction end side and the discharge end side are located on the opposite side to the eccentric direction of the rotating body, and the width of the crescent-shaped space in the working chamber is the most. Axial over wide area Fluid compressor, characterized in that provided respectively by Luo face.