JPH0463990A - Fluid compressor - Google Patents

Abstract

PURPOSE:To sufficiently feed oil to reduce friction loss and sliding loss by providing a flow passage to introduce lubricating oil leaked in the space for pressurizing on the discharge end side of a cylinde to a power transmitting means and one side of a suction side groove. CONSTITUTION:In a compressor 1, a flow passage 32 of which one end is opened at a pressurizing space 31 of low pressure and the other end is opened at an Oldham's ring 15 is provided in a rod 11 in parallel with the axial direction. Lubricating oil 29 introduced into a helical groove 19 is leaked between the outer circumferential face of a blade 21 and the inner circumferential face of a cylinder 7, and entered into the pressurizing space 31 on the discharge side together with gas. The lubricating oil gathered in the space 31 is introduced to an Oldham's ring 15 through the flow passage 32, and the sliding face between the Oldham's ring 15 and the rod 11 is lubricated. Hereby, feed oil to the Oldham's ring 15 is insured, and sliding loss between the Oldham's ring and the rod 11 can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION OBJECTS OF THE INVENTION (Industrial Field of Application) The present invention relates to a fluid compressor for compressing refrigerant gas, for example in a refrigeration cycle, and in particular to a fluid compressor with spiral blades.

(Prior Art) Various types of compressors, such as a reciprocating type and a 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 compression section are complicated, and the number of parts is large. Furthermore, in conventional compressors, it is necessary to provide a check valve on the discharge side of the compressor in order to increase compression efficiency. However, the pressure difference between both sides of this check valve is very large, and gas tends to leak from the check valve. Therefore, 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 results in higher manufacturing costs.

In recent years, fluid compressors equipped with spiral blades have been provided to solve the above problems.

This type of compressor includes a cylinder and a rotary rod that is eccentrically disposed within the cylinder and is rotatable relative to the cylinder. A spiral groove is formed on the outer peripheral surface of the rod over substantially the entire length of the rod,
A spiral blade is fitted into this spiral groove. The outer peripheral surface of the blade is in close contact with the inner peripheral surface of the cylinder. and,
As the rod pivots relative to the cylinder, the blade slides in the spiral groove in the radial direction of the rod.

The space between the rod and the cylinder is partitioned into a plurality of spaces by blades. And the pitch of the spiral groove is
The rod gradually becomes smaller from one end to the other end, and therefore, the volumes of the plurality of spaces also gradually become smaller from one end of the rod to the other end. Therefore,
The fluid sucked into the space from one end of the rod is
The fluid is conveyed to the other end of the rod while confined in the space, and during this time, the fluid is gradually compressed and finally discharged from the other end of the rod.

The compressed fluid discharged from the other end of the rod enters the airtight case of the compressor body, which rotatably supports the cylinder and is housed inside, and is sent to the refrigerator via the discharge tube that communicates with the case. It will be done.

On the other hand, lubricating oil is stored at the bottom of the case, and when the pressure inside the case increases, it is introduced into the space between the bottom of the groove and the blade. This oil passage is formed in the axial direction through the center of the rod, and the tip of the passage opens into a spiral groove on the discharge end side where high pressure back pressure is applied, and into a spiral groove on the low pressure suction end side. The lubricating oil is flowed towards the cylinder to ensure even lubrication.

For this reason, conventionally, the spiral groove on the low-pressure suction end side and the Oldham ring, which is a power transmission means provided on the rod on the suction end side and transmits the rotation of the cylinder to the rod in synchronization, are not sufficiently lubricated. There was a possibility that it wouldn't happen.

(Problems to be Solved by the Invention) As mentioned above, in the conventional spiral blade type compressor, lubricating oil is not sufficiently supplied to the spiral groove and the Oldham ring on the suction end side, and the spiral groove and the blade are There was a problem in that the friction loss between the Oldham ring and the rod and the sliding loss between the Oldham ring and the rod increased.

This invention was made in view of these points, and it is possible to supply sufficient oil to the spiral groove on the suction end side and the Oldham ring, thereby reducing friction loss between the blade and the spiral groove and between the Oldham ring and the rod. The purpose of the present invention is to provide an efficient fluid compressor that can reduce sliding loss between the two.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a cylinder that sucks compressed fluid from one end and discharges it from the other end, and a cylinder that is eccentrically located along the axial direction of the cylinder. a cylindrical rotating body that is rotatably supported relative to the cylinder with a part of its outer circumferential surface in contact with the inner circumferential surface of the cylinder; a spiral groove formed at a pitch that gradually decreases from the suction end side to the discharge end side of the cylinder; and a spiral groove that is slidably fitted in the groove along the radial direction of the rotating body; having an outer circumferential surface in close contact with an inner circumferential surface of the cylinder,
a spiral blade that divides 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 power transmission means that synchronously transmits the rotation of the cylinder to the rotary body. , in a fluid compressor comprising preload spaces provided at both ends of the rotary body and means for supplying lubricating oil into the groove, the lubricant leaked into the pressurization space on the discharge end side of the cylinder; A flow path that guides oil to at least one of the power transmission means and the suction side groove,
It is characterized in that it is provided on the rotating body.

(Function) According to the above configuration, the low-pressure lubricant leaked from the groove and accumulated in the pressurizing space on the discharge end side is transferred to the Oldham ring, which is the power transmission means, through the flow path provided in the rotating body. be guided. As a result, the Oldham ring can be reliably lubricated, and the sliding loss between the Oldham ring and the rod can be reduced. Furthermore, by guiding the lubricating oil to the low-pressure suction side groove through the flow path, it is possible to reduce friction loss between the first spring blade on the suction side and this groove.

(Embodiments) Hereinafter, embodiments of the present invention will be described in detail without reference to the drawings.

FIG. 1 shows an embodiment in which the present invention is applied to a hermetic compressor for compressing refrigerant in a refrigeration cycle.

The compressor 1 includes a closed case 2, an electric motor section 3 and a compression section 4 disposed within the closed case 2. The electric motor section 3 includes a substantially annular stator 5 fixed to the inner surface of the case 2 and an annular rotor 6 provided inside the stator.

The compression section 4 has a cylinder 7, and a rotor 6 is coaxially fixed to the outer peripheral surface of the cylinder.

Both ends of the cylinder 7 are rotatably supported by bearings 8 and 9 fixed to the inner surface of the case 0, respectively, and are hermetically closed. In particular, the right end of the cylinder 7, that is, the suction side end, is rotatably supported by a bearing 8, and the left end, that is, the discharge side end of the cylinder, is rotatably supported by a bearing 9. The bearings 8 and 9 have boss parts 8a and 9a that are rotatably inserted into the end of the cylinder 7, and a base part 8b that has a larger diameter than the boss part and is fixed to the inner surface of the case 2.

9b. Therefore, the cylinder 7 and the rotor 6 fixed thereto are supported coaxially with the stator 5 by the bearing 89.

Inside the cylinder 7, a cylindrical rotating rod 11 having a smaller diameter than the inner diameter of the cylinder is disposed along the axial direction of the cylinder. The rod 11 is made of metal such as iron. The rod 11 is located eccentrically by a distance e with respect to its central axis A or the central axis B of the cylinder 7, and a portion of its outer circumferential surface is in line contact with the inner circumferential surface of the cylinder.

A support shaft 12a is provided at both ends of the rotating rod 11.

12b are provided in a protruding manner. These support shafts 12
a, 12b are bearing holes 8c, 9 formed in the bearings 8, 9;
It is rotatably inserted into c.

As shown in FIGS. 1 to 4, one support shaft 12a
A prismatic portion 13 having a square cross section is formed in the. An Oldham ring 15 having a rectangular elongated hole]4 is attached to this prismatic portion 13. That is, the prismatic portion 13 is inserted into the elongated hole 14 of the ring 15, and the ring is fitted to be slidable along the elongated hole. The ring 15 has a long hole 1
A pair of through holes are formed that extend in the radial direction perpendicular to the longitudinal direction of the pin 16, and one end of the pin 16 is slidably inserted into these through holes. The other end of each pin 16 is fixed within a through hole 17 formed in the cylinder 7. Note that the outer end of each through hole 17 is hermetically closed with a cap 18.

The rod 11 is supported with respect to the cylinder 7 by the Oldham ring 15 configured as described above so as to be eccentric in the radial direction of the cylinder. Therefore, when the electric motor section 3 is energized and rotated integrally with the cylinder 7 or the rotor 6, the rotational force of the cylinder is transmitted to the rotating rod 11 via the Oldham ring 15. As a result, the rod 11 is internally rotated within the cylinder with a portion of the rod 11 in contact with the inner peripheral surface of the cylinder 7, and rotates relative to the cylinder 7.

As shown in FIGS. 1 to 3, a spiral groove 19 is formed on the outer peripheral surface of the rotary rod 11 and extends between both ends of the rod. The grooves 19 are formed such that the pitch thereof gradually decreases from the right end to the left end of the cylinder 7, that is, from the suction side to the discharge side of the cylinder. In addition, the total length of the groove 19 is the same as that of the blade 2, which will be described later.
As shown in FIG. 3, a gap G is provided between the end of the groove 19 and the end of the blade 21 when the rod 11 is assembled into the cylinder 7.

The gap G is provided in order to allow a relative movement, in particular a pivoting movement, of the plate 2 with respect to the rod 1.

The total length of both gaps G is set to be approximately twice or more the eccentricity e of the rod 11 with respect to the cylinder 7. Here, for example, due to thermal expansion of the blade 21, etc., the total dimension of the gap may not be exactly twice the eccentricity e, but may be less than twice. In consideration of this point, the above-mentioned total dimension is set to be approximately twice or more the eccentricity e.

A spiral blade 21 shown in FIGS. 2 and 3 is fitted into the groove 19 of the rod 11. As shown in FIGS.

The blade 21 is made of an elastic material such as synthetic resin, and is inserted into the groove 19 by utilizing its elasticity. The thickness of the blade 21 is the groove 19
It almost matches the width of . Both ends of the blade 21 are located in a plane perpendicular to the axis of the rod 11, and face the end of the groove 19 with a gap G therebetween. Note that when the blade 21 is installed in the groove 19, the blade may be provided biased toward one end of the groove, that is, so that a gap 2G is formed at one end of the blade. Each part of the blade 21 is connected to the rotating rod 1 with respect to the groove 19.
] It is movable forward and backward along the radial direction. Further, the outer peripheral surface of the plate 21 is in close contact with the inner peripheral surface of the cylinder 7.

As shown in FIG. 1, the space between the inner peripheral surface of the cylinder 7 and the outer peripheral surface of the rod 11 is partitioned into a plurality of working chambers 22 by blades 21. As shown in FIG. Each working chamber 22 is
It is defined between two adjacent windings of the blade 21,
As shown in FIG.
It has a substantially crescent shape extending from the contact point between the inner peripheral surface of the cylinder 7 and the inner peripheral surface of the cylinder 7 to the next contact point. 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. 1, a suction hole 23 extending in the axial direction of the cylinder 7 is formed through the bearing 8 that supports the suction side end of the cylinder 7. One end of this suction hole 23 opens into the suction side end of the cylinder 7, and the other end is connected to the suction tube 24 of the refrigeration cycle. Also,
A discharge hole 25 is formed at the discharge side end of the cylinder 7. One end of the discharge hole 25 opens into the discharge side end of the cylinder 7, and the other end opens into the inside of the case 2.

Further, an oil introduction passage 26 is formed inside the rod 11 and extends from the right end of the rod to approximately the middle thereof. The right end of the passage 26 is connected to a passage 27 formed in the bearing 8 and the introduction pipe 2.
8, it communicates with the inside of the case 2, particularly the bottom of the case. The left end of the passage 26 is connected to the groove 1 formed in the rod 11.
It opens at the bottom of 9. Lubricating oil 29 is stored at the bottom of the case 10. Therefore, when the pressure inside the case 2 increases, the oil 29 flows through the inlet pipe 28 and the passage 27°26.
is introduced into the space between the bottom of the groove 19 and the blade 21 through it.

In addition, a support shaft 1 provided at the suction side end of the rod 11
A high-pressure preload space 30 is provided between the end face of 2a and the suction side bearing 8. Similarly, a low-pressure preload space 31 is provided between the end surface of the support shaft 12'b provided at the discharge side end of the rod 11 and the discharge side bearing 9. When the pressure inside the sealed case 2 rises due to the gas compressed by the rotation of the rod 11 and discharged into the sealed case 2 from the discharge port 25, the lubricating oil 29 passes through the introduction pipe 28 and the passage 27 and enters the preload space 30. is introduced into the preload space 30 to create high pressure. As a result, the thrust force acting on the rod 11 in the direction of arrow C is balanced, and the rod 11 is maintained at a predetermined position in the axial direction.

Further, in the rod 11, a passage 32 is provided in parallel with the axial direction, one end of which opens into a low-pressure preload space 30. It opens into the hole 14. In addition, in FIG. 1, the reference numeral 33 is a discharge tube communicating with the inside of the case 2.

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

First, when the electric motor section 3 is energized, the rotor 6 rotates,
The cylinder 7 also rotates together with this. At the same time, the rotating rod 11 is driven to rotate with a portion of its outer circumferential surface in contact with the inner circumferential surface of the cylinder 7 .

Such relative eccentric rotational movement between the rod 11 and the cylinder 7 is ensured by a transmission means, that is, an Oldham ring 15 provided on the prismatic portion 13 of the support shaft 12a.

The blade 21 is pressed toward the outer peripheral surface of the cylinder 7 by the pressure of the lubricating oil introduced into the bottom of the spiral groove 19 through the oil introduction path 26, and the outer peripheral surface of the blade is pressed against the outer peripheral surface of the cylinder 7.
It is in close contact with the inner peripheral surface of.

Therefore, the frictional force between the blade 21 and the cylinder 7 is greater than the frictional force between the blade 21 and the rod 1], and 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 performs a turning motion with respect to the rod 11.

In this way, each part of the blade 21 is pushed into the groove 19 as it approaches the contact area between the outer circumferential surface of the rod 11 and the inner circumferential surface of the cylinder 7, and moves in the direction of popping out of the groove as it moves away from the contact area. .

That is, each part of the blade 21 moves relative to the rod 11 in the radial direction of the cylinder 7.
The groove 19, which is held between two grooves, is longer than the end of the blade 21 and has a play portion G, which is longer than the length that allows the rod 11 to pivot when the compressor is assembled. Therefore, the blade 21 pivots relative to the rod 11 and rotates integrally with the cylinder 7 without substantially sliding.

On the other hand, when the compression section 4 is activated, refrigerant gas is sucked into the cylinder 7 through the suction tube 24 and the suction hole 23 . This gas is first confined in the low-pressure side working chamber 22a located closest to the suction side of the cylinder 7. As the rotating rod 11 rotates, the gas is transferred to the blade 21.
The liquid is trapped between two adjacent windings and is sequentially transferred to the working chamber on the discharge side. Since the volume of the working chamber 22 gradually decreases from the suction side to the discharge side of the cylinder 7, the refrigerant gas is compressed in the gaps as it is transferred to the discharge side.

The compressed refrigerant gas then reaches the high-pressure side working chamber 12b, is discharged into the case 2 from the discharge hole 25 formed in the cylinder 7, and is further returned into the refrigeration cycle through the discharge tube 33.

When the pressure inside the case 2 increases due to the discharged refrigerant gas, the lubricating oil 29 stored inside the case is pressurized and passes through the oil introduction path 26 into the space between the bottom of the spiral groove 19 and the blade 21. will be introduced in Therefore, blade 2
1 is pressed in the direction of popping out from the groove 19 by hydraulic pressure, that is, toward the inner circumferential 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. As a result, gas leakage between the working chambers 22 can be reliably prevented.

According to the compressor configured as described above, the rotating rod 1
The grooves 19 formed in the cylinder 7 are 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. Thus, the refrigerant gas can be compressed during its transfer from the suction side to the discharge side of the cylinder 7 through the working chamber 22 . Further, since the refrigerant gas is transferred and compressed while being confined within the working chamber 22, the gas can be efficiently compressed even if no discharge valve is provided on the discharge side of the compressor.

On the other hand, the lubricating oil 29 introduced into the spiral groove 19 leaks from between the outer circumferential surface of the blade 21 and the inner circumferential surface of the cylinder 7, and enters the low-pressure preload space 30 on the discharge side together with the gas. The lubricating oil 29 accumulated in this preload space 30 is
It passes through a flow path 32 provided in the rod 11 and is guided into the elongated hole 14 of the Oldham ring 15. The inner circumference of the elongated hole 14 of the Oldham ring 15 and the support shaft 12a of the rod 11
lubricates the sliding surface with the prismatic portion 13 provided on the surface.

According to this embodiment, the Oldham ring 15, to which lubricating oil has not been sufficiently supplied in the past, can be sufficiently lubricated, and the sliding loss of the Oldham ring 15 can be reduced. As a result, the efficiency of the compressor can be improved.

Furthermore, since the discharge valve can be omitted, the configuration of the compressor can be simplified and the number of equipment can be reduced. Further, since the rotor 6 of the electric motor section 3 is supported by the cylinder 7 of the compression section 4, there is no need to provide a dedicated rotating shaft, bearing, etc. for supporting the rotor. Therefore, it is possible to further simplify the configuration of the compressor and reduce the number of parts.

FIG. 5 shows another embodiment of the invention. In the drawings, parts that are the same or equivalent to those in the embodiment shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

In this embodiment, one end on the suction side of the flow path 32 formed in the rod 11 was opened to the groove 17 closest to the suction side.

In this embodiment, as in the previous embodiment, the groove 17 on the suction side can be sufficiently lubricated, and the friction loss between the blade 21 on the suction side and the groove 17 can be reduced.

Note that this invention is not limited to the embodiments described above, and can be modified in various ways within the scope of this invention. For example, the present invention is not limited to compressors combined with refrigeration cycles;
It can also be adapted to other compressors.

In addition, the flow path 32 is connected to the groove 19 on the suction side and the Oldham ring 15.
It may be opened in both directions.

〔Effect of the invention〕

As explained above, according to the present invention, the flow path that guides the lubricating oil leaked into the pressurized space on the discharge end side of the cylinder to at least one of the Oldham ring and the suction side groove, which are the power transmission means, is rotated. Since it was installed on the rod which is the body,
The friction loss between the blade and the groove and the sliding loss of the Oldham ring can be reduced, and the efficiency of the fluid compressor can be improved.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view showing the configuration of an embodiment of the present invention, Fig. 2 is an exploded view, Fig. 3 is a perspective view showing the rod, and Fig. 4 is a cross section taken along line D-D in Fig. 1. 5 are longitudinal sectional views showing the structure of another embodiment of the present invention. 1... Compressor 7... Cylinder 11... Rotating body (rotating rod) 15... Power transmission means (Oldham ring) 19...
Groove 21...Blade 22...Working chamber 30.31...Preload space 32...Flow path

Claims (1)

[Scope of Claims] A cylinder that sucks in compressed fluid from one end and discharges it from the other end, and is provided eccentrically along the axial direction of the cylinder within this cylinder, and a part of the outer peripheral surface is adjacent to the inner peripheral surface of the cylinder. a cylindrical rotating body that is rotatably supported relative to the cylinder while being in contact with the cylinder; It has a spiral groove formed at a decreasing pitch, and an outer circumferential surface that is slidably fitted in the groove along the radial direction of the rotating body and that is in close contact with the inner circumferential surface of the cylinder, a spiral blade that divides 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 power transmission means that synchronously transmits the rotation of the cylinder to the rotary body. , a fluid compressor comprising preload spaces provided at both ends of the rotating body, and means for supplying lubricating oil into the groove, wherein the lubricant leaks into the pressurizing space on the discharge end side of the cylinder. A fluid compressor, characterized in that the rotating body is provided with a flow path that guides oil to at least one of the power transmission means and the suction side groove.