JPH0732952Y2 - Fluid compressor - Google Patents

Description

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

(Prior Art) Various types of compressors such as a reciprocating system and a rotary system have been conventionally known. However, in these compressors, the structure of the drive unit such as the crankshaft that transmits the rotational force to the compressor unit and the structure of the compression unit are complicated, and the number of parts is large. Further, in such a conventional compressor, a check valve needs to be provided on the discharge side in order to improve the compression efficiency. However, since the pressure difference between both sides of this check valve is very large, Gas leaks easily and compression efficiency is low. Then, in order to solve such a problem, it is necessary to improve the dimensional accuracy and the assembly accuracy of each component, which increases the manufacturing cost.

A screw pump is disclosed in US Pat. No. 2,401,189. According to this pump, a cylindrical rotating body is arranged 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 rotationally driving the rotating body, the fluid trapped between two adjacent windings of the blade between the outer peripheral surface of the rotating body and the inner peripheral surface of the sleeve is transferred from one end side to the other end side of the sleeve. In other words, the above-mentioned screw pump only transfers fluid from one end to the other,
It does not have the function of compressing fluid.

(Problems to be solved by the invention) As described above, the conventional fluid compressor has a complicated structure and a large number of parts. Furthermore, the gas may leak from the check valve provided on the boundary between the high pressure side and the low pressure side, and the compression efficiency was low. Further, the screw pump of the type in which the rotary body wound with the spiral blade is arranged in the sleeve merely transfers the fluid and has no compression action.

An object of the present invention is to provide a fluid compressor having excellent durability and high reliability.

[Structure of the Invention] (Means and Actions for Solving the Problems) In order to achieve the above object, the present invention is formed with a hollow cylinder, a rotor eccentrically arranged in the cylinder, and a rotor. A spiral groove having an unequal pitch, and a blade fitted into the groove to partition and form a plurality of working chambers between the rotor and the cylinder, and the blade is made of a plurality of materials having different hardnesses. There is something I did.

By doing so, the present invention is intended to prevent wear of the blade and improve the durability and reliability of the fluid compressor.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 to 7.

FIG. 1 shows an embodiment of the present invention. And
FIG. 1 shows a hermetic compressor 1 for a refrigerant gas used in a refrigeration cycle. This compressor 1 has a closed case 2,
The hermetically sealed case 2 is provided with an electric element 3 and a compression element 4 as drive means. The electric element 3 has 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.

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, and both ends of the cylinder 7 are hermetically closed by the bearings 8 and 9.

Further, in the cylinder 7, a cylindrical piston having an outer diameter smaller than the inner diameter of the cylinder 7 is used as a rotating body.
10 are arranged along the axial direction of the cylinder 7. The piston 10 is made of, for example, aluminum or aluminum alloy. And this piston
10 is arranged with its center axis A eccentric to the center axis B of the cylinder 7 by a distance e.
A part of the outer peripheral surface of is in contact with the inner peripheral surface of the cylinder 7.
The both ends of the piston 10 are rotatably supported by the bearings 8 and 9, respectively.

As shown in FIGS. 1 and 5, an engaging groove 11 is formed on the outer circumference of one end of the piston 10, and the engaging groove 11 projects from the inner peripheral surface of the cylinder 7. Drive pin 12
Is inserted in the radial direction of the cylinder 7 so as to be movable back and forth. Therefore, when the electric element 3 is energized and the cylinder 7 is rotationally driven integrally with the rotor 6, the rotational force of the cylinder 7 is transmitted to the piston 10 via the drive pin 12. Then, the piston 10 rotates inward in the cylinder 7 with the axis A as the center and a part of the piston 10 in contact with the inner surface of the cylinder 7.

Further, a spiral groove 13 extending between both ends of the piston 10 is formed on the outer peripheral surface of the piston 10. The spiral groove 13 is formed at a gradually smaller pitch from the right side to the left side in both figures, that is, from the suction side to the discharge side of the cylinder 7. The spiral groove 13 has a smaller gradient in the radial direction of the piston 10 as it goes from the suction side to the discharge side.

Further, the groove 13 has a spiral blade 14 shown in FIG.
Is fitted. The blade 14 is formed by, for example, integrally injection molding a synthetic resin material or the like. The blade 14 has a proper elasticity. The thickness t of the blade 14 is substantially equal to the width of the spiral groove 13, and each portion of the blade 14 is movable back and forth in the radial direction of the piston 10 with respect to the groove 13. .

Further, the blade 14 is formed by using two kinds of materials. That is, the blade 14 shown in FIG. 3 has substantially the entire length, and one side surface 14a side and the other side surface 14b side are made of materials having different hardness. As shown in FIG. 4, the blade 14 has one side 14a on the other side 1a.
It is made of a harder material than the 4b side. Furthermore, the two materials forming the blade 14 have approximately the same thickness, and the boundary between the two materials is the inner peripheral surface 15 of the blade 14.
(And the outer peripheral surface 16) in the widthwise middle portion. The thicknesses of these two materials may be different from each other.

The outer peripheral surface 15 of the blade 14 slides on the inner peripheral surface of the cylinder 7 in close contact with the inner peripheral surface of the cylinder 7. The blade 14 is screwed in by utilizing its elasticity and is mounted in the spiral groove 13.

Further, the space between the inner peripheral surface of the cylinder 7 and the outer peripheral surface of the piston 10 is divided into a plurality of working chambers 17 by the blades 14.
It is divided into ... In other words, each working chamber 17 has a blade 14
Is formed between two adjacent turns of the piston 10 and has a substantially crescent shape extending from the contact portion between the piston 10 and the inner peripheral surface of the cylinder 7 to the next contact portion along the blade 14. The volume of the working chambers 17 gradually decreases from the suction side of the cylinder 7 to the discharge side.

Further, as shown in FIG. 4, of the two working chambers 17a, 17b adjacent to each other with a part of the blade 14 located, the working chamber 17a located on the suction side faces one side surface 14a of the blade 14. The working chamber 17b located on the discharge side is the other side surface 1 of the blade 14.
Facing 4b.

As shown in FIG. 1, the bearing 8 located on the suction side of the cylinder 7 has a suction hole extending in the axial direction of the cylinder 7.
18 penetrates. Then, one end of the suction hole 18 is opened into the cylinder 7, and the other end thereof is connected with a suction tube 19 of the refrigeration cycle.

Further, a discharge hole 20 is formed in the other bearing 9.
One end of the discharge hole 20 is open to the discharge end side in the cylinder 7. The discharge hole 20 extends in the axial direction of the bearing 9 and is bent at an intermediate portion thereof. The other end of the discharge hole 20 extends to the side surface of the bearing 9 and opens inside the sealed case 2.

Reference numeral 21 in FIG. 5 is a pressure introducing passage. That is, the pressure introducing passage 21 is provided along the central axis A of the piston 10, and one end of the pressure introducing passage 21 is provided inside the closed case 2 through the passage 22 formed in the bearing 9 on the discharge side, in particular, It communicates with the bottom of the closed case 2. Further, the other end of the pressure introducing passage 21 opens at the bottom of the spiral groove 13 formed in the piston 10. And the sealed case 2
As shown in FIG. 1, lubricating oil 23 is stored in the bottom of the.

That is, as the pressure in the closed case 2 rises, the oil 23 passes through the passage 22 of the discharge side bearing 9 and the pressure introducing force passage 21 and is between the bottom of the groove 13 and the blade 14. Will be introduced into the space. It should be noted that one end of the pressure introducing passage 21 is opened in a portion of the groove 13 that has advanced from the suction side end of the cylinder 7 to the discharge side end side by an angle slightly larger than 360 degrees.

Here, reference numeral 24 in FIG. 1 denotes a discharge tube for communicating the inside and outside of the closed case 2.

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

First, when the electric element 3 is energized, the rotor 6 rotates, and the cylinder 7 integrally rotates with the rotor 6 synchronously. At the same time, the piston 10 is rotationally driven with a part of its outer peripheral surface in contact with the inner peripheral surface of the cylinder 7. Such relative rotational movement between the piston 10 and the cylinder 7 is ensured by the restricting means including the drive pin 12 and the engaging groove 11. Then, the blade 14 also rotates integrally with the piston 10.

Furthermore, since the blade 14 rotates with its outer peripheral surface 16 in contact with the inner peripheral surface of the cylinder 7, each part of the blade 14 approaches the contact portion between the outer peripheral surface of the piston 10 and the inner peripheral surface of the cylinder 7. It is pushed into the groove 13 and moves in a direction of jumping out of the groove 13 as it is separated from the contact portion. On the other hand, when the compression element 4 is activated, the suction tube 19
A refrigerant gas (not shown) is sucked into the cylinder 7 through the suction hole 18.

The sucked refrigerant gas is shown in FIGS. 6 (a) to 6 (d).
As shown in Figure 3, the crescent-shaped working chamber between the turns of the blade 14
In the state where the piston 10 is closed, the piston 10 is sequentially transferred to the working chamber 17 on the discharge side as the piston 10 rotates. The transferred and compressed refrigerant gas is discharged into the space of the closed case 2 from the discharge hole 20 formed in the discharge side bearing 9, and is further returned to the refrigeration cycle through the discharge tube 24.

When the pressure in the closed case 2 rises, the discharge side bearing 9 is formed in the space between the bottom of the spiral groove 13 and the blade 14.
Through the passage 22 and the pressure introduction passage 21
23 will be introduced. Therefore, the blade 14 is always pressed by the hydraulic pressure in the direction of being pushed out from the groove 13, that is, toward the inner peripheral surface of the cylinder 7.

Therefore, during the operation of the compression element 4, the blade 14 smoothly advances and retreats along the radial direction of the cylinder 7. Therefore,
The outer peripheral surface 16 of the blade 14 is always kept in close contact with the inner peripheral surface of the cylinder 7. Also, from this, the working chamber 15
The blades 14 are securely separated from each other, and the working chamber 17
Gas leakage between them is prevented.

According to the compressor 1 configured as described above, the piston 10
The spiral groove 13 formed in is formed so that the pitch becomes gradually smaller from the suction side to the discharge side of the cylinder 7. In other words, the working chambers 17 ... Partitioned by the blade 14 are formed so that the volume gradually decreases toward the discharge side. Therefore, the refrigerant gas can be compressed while being transferred from the suction side to the discharge side of the cylinder 7. Further, since the refrigerant gas is transferred and compressed while being confined in the working chamber 17, the compressor 1
Even if the check valve is not provided on the discharge side, the gas can be compressed efficiently.

Furthermore, since the check valve can be omitted, the structure of the compressor can be simplified and the number of parts can be reduced. Further, since the rotor 6 of the electric element 3 is supported by the cylinder 7 of the compression element 4, it is not necessary to provide a dedicated rotating shaft or bearing for supporting the rotor 6. Therefore, the structure of the compressor can be further simplified,
It is possible to reduce the number of parts.

Further, since the spiral blade 14 is composed of two materials having different hardness, the blade 14 is unlikely to be deformed during the operation of the compressor, and the piston of the blade 14 is not deformed.
Easy to assemble to 10. That is, the blade 14 is the seventh
As shown by the arrow C ... in the figure, the working chambers 17a, 17b on both sides of it
It receives a force due to the differential pressure Δp. And blade 14
Moves in and out of the spiral groove 13 of the piston 10 with its suction side surface 14a being pressed against the inner wall 25 of the piston 10.

However, since the suction side surface 14a of the blade 14 has a higher hardness than the discharge side surface 14b, the suction side surface 14a is less likely to be worn by the differential pressure Δp. Further, since the hardness on the suction side surface 14a side of the blade 14 is made higher than that on the discharge side surface b side by using different materials, the deformation due to the differential pressure Δp ... Is unlikely to occur. Then, the fall of the blade 14 from the discharge side to the suction side can be prevented. From the above, the durability of the compressor 1 for long-term operation can be improved and high reliability can be secured.

Further, when the blade 14 is harder than necessary, it is difficult for the blade 14 to elastically deform, which makes it difficult to assemble the blade 14 to the piston 10. However, the discharge side 14b of the blade 14
Is made of a material that is softer than the suction side surface 14a, it has high hardness and sufficient elasticity. Therefore, it is easy to wind the blade 14 around the piston 10.

Further, since the blade 14 has sufficient elasticity, the blade 14 operates smoothly even at a portion having a large gradient located at the suction side end of the piston 10. Also, the blade
Since 14 operates smoothly, there is little gas leakage.
Therefore, the operation input of the refrigerant gas can be set small.

During operation of the compressor, hydraulic pressure is supplied to the space between the groove 13 and the blade 14, and the blade 14 is constantly pressed toward the inner peripheral surface of the cylinder 7. Therefore, the blade 14
Rotates with its outer peripheral surface in close contact with the inner peripheral surface of the cylinder 7. Therefore, the adjacent working chambers 17 can be reliably partitioned, and the gas leak between the working chambers 17 can be reliably prevented. Therefore, it is possible to efficiently compress the gas.

Further, since the blade 14 is pressed toward the inner peripheral surface of the cylinder 7, the blade 14 follows the inner surface of the cylinder 7 even if the manufacturing accuracy of parts such as the squareness of the blade 14 is not so high. It smoothly moves in the groove 13 along the radial direction of the cylinder 7. Therefore, it is possible to easily manufacture and assemble the parts.

Further, by introducing high-pressure lubricating oil into the space between the bottom of the groove 13 and the blade 14, the inner surface of the groove 13 and the blade 14 are
It is possible to lubricate the space between and and to seal between them. Furthermore, since the space is formed in a spiral shape along the groove 13, this space acts as a hydraulic pump and can guide the lubricating oil to other sliding parts.

Further, the cylinder 7 and the piston 10 are in contact with each other in a state of being synchronized with each other and rotating in the same direction. For this reason,
The friction between these members is small and they can rotate smoothly, so there is little vibration or noise.

Further, the transfer capacity of the compressor is determined by the first pitch of the blades 14, that is, the working chamber 17 located on the suction end side of the cylinder 7.
Determined by the capacity of. According to this embodiment, the pitch of the blades 14 gradually decreases from the suction side to the discharge side of the cylinder 7. Therefore, the blade 14 can have a larger initial pitch than the one having the same number of turns as the present embodiment and the same pitch over the entire length of the piston 10, and the compressor can be transferred. A large capacity can be taken. In other words, a highly efficient compressor can be realized.

Although the transfer capacity is reduced, as the number of windings of the blade 14 is increased, the pressure difference between the adjacent working chambers is reduced, the gas leak amount between the working chambers is reduced, and the compression efficiency is improved.

In this embodiment, the suction side surface 14a side and the discharge side surface 14b side of the blade 14 are made of different materials, but the present invention is not limited to this, and the blade 14 is For example, it may be molded as shown in FIG. That is, the blade 14 shown in FIG. 8 has a suction side (low stage side).
The part 26 and the discharge side (higher step side) part 27 are made of different kinds of materials. And this blade 14
The part 26 on the suction side of is formed of a material softer than the material used for the part 27 on the discharge side. That is, in the blade 14, the suction side portion 26 where the gradient of the piston 10 in the radial direction is large is more easily elastically deformed than the discharge side portion 27.

Further, since the hardness of the discharge side portion 27 exposed to the high pressure environment is higher than that of the suction side portion 26, the blade 14 is less likely to be deformed or worn and has excellent durability.

Further, the durability of the compressor 1 can be further improved by subjecting the piston 10 to anodizing treatment to form a film. That is, as shown in FIG. 7, the piston 10
In the inner walls 25, 25 of the groove 13 of the two working chambers 17a, 17b adjacent to each other.
The reaction force F, F of the force from the blade 14 that separates is added. For this reason, if the strength of the wall surfaces of the inner walls 25, 25 is insufficient, when the compressor 1 is operated for a long time, the sliding portions of the inner walls 25, 25 with the blades 14 are worn, and this wear progresses. .

However, by forming the anodic oxide coating on the piston 10, the wall surfaces of the inner walls 25, 25 of the groove 13 are hardened and less likely to wear. Therefore, the sliding characteristic between the piston 10 and the blade 14 is improved, the performance is not deteriorated due to the abrasion of the piston 10, and the durability is improved.

The compressor of the present invention is not limited to the refrigeration cycle but can be applied to compressors for other purposes.

[Advantages of the Invention] As described above, the present invention has a hollow cylinder, a rotating body eccentrically arranged in the cylinder, a spiral groove formed on the rotating body and having an unequal pitch, and A blade that is fitted into the groove and defines a plurality of working chambers between the rotating body and the cylinder is formed, and the blade is formed of a plurality of materials having different hardness.

Therefore, the present invention is effective in preventing the wear of the blade and improving the durability and reliability of the fluid compressor.

[Brief description of drawings]

1 to 7 show an embodiment of the present invention.
Fig. 1 is a side sectional view showing the whole fluid compressor, Fig. 2 is a side view of a piston, Fig. 3 is a same side view of a blade, and Fig. 4 is a side sectional view showing a sliding portion between a groove of a piston and a blade. Figure,
FIG. 5 is a side view showing a compression element partially broken away, FIGS. 6 (a) to 6 (d) are side views partially showing the compression process of the refrigerant gas, and FIG. 7 is a piston. FIG. 8 is an explanatory view showing the force acting on the sliding portion between the groove and the blade, and FIG. 8 shows a modification, which is a side view of the blade. 1 ...... Compressor, 2 ...... Sealed case, 3 ...... Electric element (driving means), 7 ...... Cylinder, 10 ...... Piston (rotating body), 13 ......
Spiral groove, 14 …… blade, 17 …… working chamber.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Creator Tetsuo Fukuda 70 Yanagicho, Yanagicho, Saiwai-ku, Kawasaki, Kanagawa Prefecture, Toshiba Yanagimachi Co., Ltd. Within

Claims (1)

[Scope of utility model registration request] 1. A hollow cylinder, a rotating body eccentrically arranged in the cylinder, a spiral groove formed in the rotating body and having an unequal pitch, the rotating body and the rotating body fitted in the groove. A fluid compressor, comprising: a blade for partitioning and forming a plurality of working chambers between the cylinder and the cylinder, the blade being formed of a plurality of materials having different hardness.