JP2829018B2 - 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 the assembling accuracy of each component, but this increases the manufacturing cost.

On the other hand, the present applicant has previously filed a helical blade type compressor shown in FIG. FIG. 11 shows a main part of a conventional helical blade type fluid compressor, which is disposed eccentrically (e in FIG. 11 indicates the amount of eccentricity) inside a cylinder a. A rotating body b that makes a revolving motion (eccentric rotating motion) relative to the cylinder a, and a blade d inserted into a groove c (see FIG. 12) formed in a spiral shape on the outer surface of the rotating body b. Have. The blade d slides in the groove c and moves in and out in the depth direction along with the turning movement of the rotating body b with respect to the cylinder a. And both ends of the cylinder a and the rotating body b are rotatably supported by bearings f and g,
Each of the bearings f and g is provided with a suction port h and a discharge port j. The pitch of the groove c gradually narrows from the suction port h toward the discharge port j.

Due to the frictional force between the rotating body b and the blade d that moves in and out in the depth direction based on this pitch change, the pushing-up force of the blade d in the direction of the cylinder a on the suction end side decreases, and therefore, the blade d and the cylinder a is likely to be generated between them. Therefore, in order to solve such a problem, the suction side end of the blade d has a helical pitch reduced within a range of one turn, and a portion for vertically receiving a pushing force from the cylinder a to the blade d is provided. The end of the blade is easily moved in and out on the suction end side.

In such a configuration, the cylinder a and the rotating body b
Is relatively swirled, the fluid to be compressed such as gas sucked into the space between the cylinder a and the rotating body b from the suction port h is compressed. That is, the space is cylinder a
Is moved to the discharge port j side in accordance with the turning motion of the rotating body b with respect to the above, but since the pitch of the groove c is gradually reduced, the space partitioned by the blade d, that is, the plurality of working chambers The volume gradually decreases toward the discharge port j side. Therefore, the compressed fluid entering the space is gradually compressed and finally discharged from the discharge port j.

In this compression operation, the introduction of the fluid to be compressed into the first working chamber k on the suction side is performed through an introduction passage formed by the suction side end of the blade d and the cylinder a and the rotating body b. The working chamber k at this time is 1 at the suction side end.
The blade d is formed by using an end portion of the blade d whose pitch is narrowed in the range of the winding or more, which is indicated by reference numeral d2. For this reason,
A state in which the working chamber k has a smaller volume than the second working chamber 1 occurs, and there is a disadvantage that the sucked gas expands. Therefore, there is a disadvantage that the input for compression is increased.

(Problems to be Solved by the Invention) The present invention has been made based on the above circumstances, and an object thereof is a helical blade type, which prevents loss due to expansion of a fluid to be compressed and improves efficiency. To obtain a fluid compressor that can be used.

[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 define a space between an inner peripheral surface of the cylinder and an outer peripheral surface of the rotating body into a plurality of working chambers, and the rotating body positioned on the suction side. On the outer peripheral surface of the end of
A suction groove is formed so as to cross the spiral groove and to be deeper than the groove and to introduce a compressed fluid only into a first working chamber formed on the suction side. .

(Operation) In the fluid compressor of the present invention, since the suction groove provided on the outer surface of the end portion of the rotating body is deeper than the spiral groove, even when the blade is maximally buried in the spiral groove, the blade is formed by the blade. The suction groove is not blocked. Since the suction groove traverses the spiral groove, the first working chamber always maintains a communication relationship with the suction side through the suction groove. That is, the introduction passage of the fluid to be compressed into the first working chamber can be always secured. Therefore, the substantial volume of the first working chamber communicating with the suction side can be ensured larger than the volumes of the second and subsequent working chambers, thereby preventing the suctioned compressed fluid from expanding.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 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 2, 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.

At both ends in the axial direction of the piston 11, a support shaft portion 12 is provided.
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.

A prism section 13 having a square cross section is formed on one support shaft section 12a of the piston 11 as shown in FIGS.
As shown in FIG. 4, the prism 13 is provided with an Oldham ring 15 having a rectangular long 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 around the eccentricity e as a radius in a state where a part of the cylinder 7 is in contact with 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 side to the discharge 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. By such end treatment, the blade 21 can easily enter and exit the groove 19 so that no gap is generated between the blade 21 and the cylinder 7. 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 space between the inner peripheral surface of the cylinder 7 and the outer peripheral surface of the piston 11 is partitioned into a plurality of working chambers 22 by the blade 21. 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.

One of the bearings 8 located on the suction side of the cylinder 7 has a suction hole 23 penetrating in the axial direction as shown in FIG.
One end of the suction hole 23 communicates with the inside of the cylinder 7, and the other end is connected to a suction tube 24 of a refrigeration cycle.
The other bearing 9 located on the discharge side of the cylinder 7
In FIG. 1, a discharge hole 25 is formed as shown in FIG. One end of the discharge hole 25 communicates with the discharge side of the cylinder 7, and the other end is opened inside the closed case 2.

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 at 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. .

Further, a piston located on the suction side of the cylinder 7
As shown in FIGS. 1 to 3, a suction groove 31 is cut across the spiral groove 19 on the outer peripheral surface of the end portion of the eleventh portion. The suction groove 31 is formed deeper than the spiral groove 19, and is formed, for example, along the axial direction of the piston 11, one end of which is open to the end surface of the large diameter portion 11a of the piston 11. I have. In addition, in this embodiment, due to the arrangement of the Oldham ring 15 on the suction side of the cylinder 7, the one end faces the long hole 14 of the ring 15 (see FIGS. 1 and 4). Open to the public. Due to such a positional relationship between the long hole 14 and one end of the suction groove 31, the long hole 14 is used as a passage for the refrigerant gas, and the passage resistance of the refrigerant gas sucked into the orifice ring 15 is reduced. I have. Also,
The other end of the suction groove 31 is opened to communicate only with the first working chamber 22 located on the suction side of the cylinder 7.

With the suction groove 31 having the above-described configuration, the refrigerant gas sucked from the suction tube 24 into the cylinder 7 can be reliably introduced into the first working chamber 22 through the suction groove 31 without interruption.

The suction groove 31 is provided at a position shifted in the circumferential direction of the piston 11 from the blade end 21a on the suction side as shown in FIG. 3, so that the axial dimension of the first working chamber becomes substantially maximum. The refrigerant gas is sucked through the suction groove 31 disposed at the portion where the gas flows, so that the gas can be compressed more efficiently without expanding.

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. 10, the rotation directions of the piston 7 and the piston 11 are clockwise as viewed from the suction side. Such a relative pivoting motion (rotational eccentric 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
The refrigerant gas that has passed through 24 and the suction hole 23 is sucked into the cylinder 7. This suction is performed continuously without interruption.

That is, since the suction groove 31 provided across the spiral groove 19 on the outer surface of the end of the piston 11 is deeper than the spiral groove 19, in a state where the blade 21 is pushed in and buried in the groove 19 to the maximum. Also, the suction groove 31 is not blocked by the blade 21. For this reason, the first working chamber 22 and the suction end side space (the space on the Oldham ring 15 side) can be maintained in a state of always communicating with each other through the suction groove 31. That is, a passage for introducing the refrigerant gas into the first working chamber 22 can be always secured by the suction groove 31.

Therefore, each time the piston 11 rotates once in the cylinder 7 due to the relative rotational movement between the cylinder 7 and the piston 11, the blade end 21a of the suction side end of the blade 21 is completely buried in the groove 19. Although the inlet of the introduction passage formed by the blade 21, the cylinder 7, and the piston 11 is closed by the inner peripheral surface of the cylinder 7, the suction groove 31
The refrigerant gas is always introduced into the first working chamber 22 on the suction side.

Therefore, expansion of the refrigerant gas in the compression operation described below can be prevented. In other words, the substantial volume of the first working chamber 22 that is in communication with the suction side due to the communication of the suction groove 31 can always be ensured to be larger than the volumes of the second and subsequent working chambers 22. It can prevent expansion. Therefore, an increase in input for compression can be suppressed,
The efficiency of the compressor can be improved.

As described above, the refrigerant gas sucked into the first working chamber 22 as shown in FIG. 5 is confined therein and rotates as the piston 11 rotates.
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 into a space in the sealed case 2 from a discharge hole 25 formed in the bearing 9 on the discharge 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 so that the pitch gradually decreases from the suction side to the discharge side of the cylinder 7. That is, blade 21
The working chamber 22 partitioned by is formed so that the volume gradually decreases toward the discharge side. Therefore,
During the transfer of the refrigerant gas from the suction side to the discharge side of the cylinder 7, the refrigerant gas can be compressed. 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 in the closed case 2 increases, the lubricating oil 29 stored therein 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. For this reason, the blade 21
It is constantly pressed in the direction extruded from 19, that is, 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.

In the present invention, a synchronous rotating means such as an Oldham ring for relatively rotating the cylinder 7 and the piston 11 may be arranged on the discharge side instead of the suction 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. In a helical blade type fluid compressor in which the fluid to be compressed flowing into the working chamber from the suction side of the cylinder is sequentially transferred to the working chamber on the discharge side of the cylinder and compressed, the piston located on the suction side The outer peripheral surface of the end is formed deeper than this groove across the spiral groove and has an introduction groove for introducing the compressed fluid only to the first working chamber located on the suction side. Expansion of the compressed fluid can be prevented, and thus efficiency can be improved.

[Brief description of the drawings]

1 to 10 show an embodiment of the present invention. FIG. 1 is a longitudinal sectional view showing an entire fluid compressor, FIG. 2 is an exploded view of a compression element, and FIG. 3 is a piston with a blade attached. FIG. 4 is a cross-sectional view of a portion where a piston and a cylinder are joined by an Oldham ring, FIGS. 5 to 9 are explanatory diagrams sequentially showing a process of compressing a refrigerant gas, and FIG. 10 is a side view of a compression element. FIG. FIG. 11 is a sectional view of a compression element in a conventional helical blade type compressor, and FIG. 12 is a sectional view of a rotating body used in FIG. 3 ... Electric element (drive means), 7 ... Cylinder, 11 ... Piston (rotating body), 15 ... Oldham ring, 19 ... Groove, 21 ... Blade, 22 ... Working chamber, 31 ... Suction groove, e ... Eccentricity.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hitoshi Hattori 8 Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Inside the Home Appliances Research Laboratory, Toshiba Yokohama Office (72) Inventor Naoya Sogakushi Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa No. 8 Toshiba Yokohama Works Home Appliances Research Laboratory (72) Inventor Masayuki Okuda 8 Shinsugita-cho, Isogo-ku, Yokohama, Kanagawa Prefecture Toshiba Yokohama Works Home Appliances Research Laboratory (72) Inventor Moriaki Shimoda Kanagawa 70, Yanagicho, Sachi-ku, Kawasaki-shi, Japan Inside the Toshiba Yanagimachi factory (56) References JP-A-64-36990 (JP, A) U.S.A. 61-51401 (JP, U) US Patent 2,527,536 (US, A) (58) Field surveyed (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 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 cylindrical rotator; a helical 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 having an outer peripheral surface that is in close contact with the inner peripheral surface of the cylinder and partitioning 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 fluid to be compressed is formed only on the first working chamber formed on the outer peripheral surface of the end of the rotating body located on the suction side, crossing the spiral groove and deeper than the groove, and formed on the suction side. Provision of a suction groove for introduction Fluid compressor according to claim.