JPS6329187Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention provides a mechanism for applying back pressure to the vanes of a sliding vane rotary compressor in order to push the vanes, which are retractably inserted into the rotor, toward the inner wall of the cylinder. More specifically, the lubricating oil stored at the bottom of the separation chamber is fed into the pressure groove formed in the side plate in correspondence with the end surface of the rotor by the discharge pressure in the separation chamber, and the lubricating oil in the pressure groove is The present invention relates to a compressor that is installed to apply back pressure to the vanes by feeding lubricating oil into a back pressure chamber formed at the bottom of the vane groove.

Prior Art In general, a slide vane type rotary compressor has a cylinder chamber in a space formed by a cylinder block formed in a hollow cylindrical shape and front and rear side plates that shield both front and rear end surfaces of the cylinder block. A rotor is provided so as to be freely rotatable, and a plurality of vanes are fitted into the rotor so as to be freely protrusive and retractable in the radial direction, and the vanes are pushed out toward the inner wall of the cylinder, and their tips are slid onto the inner wall surface of the rotor. It is provided so that a compression effect can be obtained by rotating the rotor while in contact with each other. And as a method of applying back pressure to the vane,
A method of sending lubricating oil separated from refrigerant gas and stored at the bottom of the separation chamber into a back pressure chamber formed at the bottom of the vane groove via the discharge pressure of the separation chamber, more specifically, as shown in FIGS. As shown in FIG. 11, pressure grooves 27 are formed in both the front and rear side plates 3F, 3R so as to face the back pressure chamber 7a formed at the bottom of the vane groove 7.
To form the pressure grooves 27F and 27R,
R is a back pressure chamber 7a such that the vane 8 extends continuously from the starting end (opening position of the suction hole) to the terminal end (opening position of the discharge hole) of the cylinder chamber 6.
Generally, a method is used in which the lubricating oil stored at the bottom of the separation chamber 15 is supplied to each back pressure chamber 7a through the pressure grooves 27F and 27R. However, in the same method, excessive back pressure is generated on the vane 8 during the suction stroke (the time when the vane 8 reaches the maximum protrusion position from the opening position of the suction hole), and the compression stroke (when the vane 8 There is a problem in that back pressure is insufficient during the period from the maximum protrusion position to the opening position of the discharge hole. That is, since the pressure grooves 27F and 27R are continuously provided from the suction stroke to the compression stroke, the same discharge pressure is maintained for the pressure grooves 27F and 27R, and the lubricating oil is However, as the volume of the back pressure chamber 7a increases due to the vane 8 being pushed out toward the inner wall of the cylinder chamber 6 during the suction stroke, the lubricating oil on the compression stroke side is Pressure grooves 27F, 27
The pressure immediately flows into the suction stroke side via R, and the pressures in the pressure grooves 27F and 27R are averaged, resulting in a phenomenon in which the pressure on the compression stroke side is substantially lowered. That is, as shown by the chain line B in FIG. 9, a phenomenon occurs in which the back pressure during the compression stroke is lower than the pressure applied to the tip of the vane.

Since the pressure in the pressure grooves 27F and 27R is constantly averaged in this way, the back pressure against the vane 8 becomes excessive during the suction stroke, and the sliding resistance of the tip of the vane 8 against the inner wall of the cylinder chamber 6 increases. As a result, the power loss increases accordingly, causing problems such as increased wear on the tip of the vane 8, and on the other hand, the back pressure against the vane 8 is insufficient during the compression stroke, causing chattering. This results in the following.
In particular, the above-mentioned problems are particularly noticeable when lubricating oil is supplied to the pressurized groove with its pressure reduced through the throttle.

Purpose of the invention The present invention is an attempt to improve the conventional situation as described above.The purpose of the invention is to apply back pressure to the suction stroke and back pressure to the compression stroke in two stages. By making it so that
Prevents excessive back pressure during the suction stroke,
The purpose is to prevent insufficient back pressure during the compression stroke.

Structure of the invention In other words, the invention has a pressure groove carved in an arc shape on the side plate side corresponding to the rotation locus of the back pressure chamber, and a pressure groove on the rear side plate corresponding to the suction stroke and the compression stroke. By dividing it into corresponding parts and making it possible to maintain high back pressure during the compression stroke without the pressure in the pressure groove on the rear side plate side being averaged, can apply a high back pressure to the vane and a lower back pressure during the suction stroke, thereby preventing excessive back pressure from being applied to the vane during the suction stroke, and It is characterized by preventing insufficient back pressure during the compression stroke, and the gist of the present invention is to extend the rotor between the front and rear end surfaces and to engrave it in the radial direction. Pressurizing grooves are formed on the front side plate and rear side plate respectively in correspondence with the rotation locus of the back pressure chamber formed at the bottom of the vane groove, and one of the pressurizing grooves discharges from the opening position of the suction hole. The other pressure groove is provided continuously from the opening position of the suction hole to just before the maximum protrusion position of the vane. The pressure groove is divided into pressure grooves that extend from immediately after the maximum protrusion position to between the opening positions of the discharge holes.

Embodiments Specific embodiments of the present invention will be described below with reference to illustrative drawings. In each of the drawings shown in FIGS. 1 to 4, reference numeral 1 denotes a housing constituting the outer shell of the compressor, and the housing 1 is a rear housing formed into a bottomed cylindrical shape with an opening on the front side. It is formed by joining the front housing 1F to the opening of 1R. A cylinder block 2 is fitted into the rear housing 1R, and a front side plate 3F and a rear side plate 3 are provided on both sides of the cylinder block 2.
R is fitted into the cylinder block 2 so as to sandwich it therebetween. That is, the cylinder block 2 is formed into a hollow cylindrical shape with openings at both front and rear ends.
The inner wall surface of the hollow portion is formed into a vertically elongated ellipse.
Both the front and rear openings of the cylinder block 2 are shielded by the side plates 3F and 3R, and a rotor shaft 4 is horizontally suspended between the side plates 3F and 3R by passing through the hollow part. A rotor 5 is mounted on the shaft 4 in correspondence with the hollow portion of the cylinder block 2. Therefore, the rotor 5 is provided so as to be able to come into sliding contact with the short diameter portion of the inner wall surface formed in a vertically elongated ellipse. A pair of cylinder chambers 6, 6 are formed therein. Further, a plurality of vane grooves 7 are formed in the rotor 5. More specifically, the vane groove 7 is formed so as to extend in the radial direction so that its front and rear ends are open to both the front and rear end surfaces of the rotor 5, and each vane groove 7 has a back pressure chamber 7a at its bottom. 7b, and vanes 8 are inserted and retracted freely.

On the other hand, a discharge chamber 9 is formed at the end of both cylinder chambers 6 by cutting out a part of the cylinder block 2, and a discharge hole 10 is provided to communicate between the discharge chamber 9 and the end of the cylinder chamber 6. It will be done. The discharge hole 10 is covered with a discharge valve 11 so as to be openable and closable. Further, a suction chamber 13 is formed between the front housing 1F and the front side plate 3F, and the suction chamber 13 is formed between the front side plate 3F and the front housing 1F.
The cylinder chamber 6 is provided so as to communicate with the starting end of the cylinder chamber 6 through a suction hole 14 that is open to the cylinder chamber 6 . Furthermore, a lubricating oil separation chamber 15 is formed between the rear side plate 3R and the rear housing 1R. Separation room 1
5 is not shown, but is provided so as to communicate with the discharge chamber 9 via a passage and a filter, and a lubricating oil reservoir 18 is provided at the bottom thereof.

A bearing portion 21R that supports one end of the rotor shaft 4 via a bearing 20R is formed in the center of the rear side plate 3R.
R is one end of rotor shaft 4 and bearing 20R
A bearing cover 22 is attached to cover the rotor shaft 4, and a bearing chamber 23 is formed between the cover 22 and the rotor shaft 4 in communication with the bearing 20R. And also, the same rear side plate 3R
A passage 24 is extended upright from the reservoir 18, and the distal end thereof is provided so as to communicate with an annular groove 25 formed so as to go around the bearing 20R. A passage 26 extends from an arbitrary position from the annular groove 25, and its tip is provided so as to face the bearing chamber 23.

Moreover, pressure grooves 27F and 27R are provided in the front side plate 3F and the rear side plate 3R so as to face both end surfaces of the rotor 5.
More specifically, the pressurizing grooves 27F and 27R are formed in an arc shape along the rotation trajectory of the back pressure chambers 7a and 7b formed at the bottom of the vane groove 7, while the pressurizing groove 27F on the front side plate 3F side is formed in an arc shape. The vane 8 is continuously provided from the starting end (opening position of the suction hole 14) to the terminal end (opening position of the discharge hole 10) of the cylinder chamber 6 (hereinafter referred to as "the third vane").
On the other hand, the pressure groove 27R on the rear side plate 3R side is a first pressure groove formed while the vane 8 extends from the opening position of the suction hole 14 to just before the maximum protrusion position. 27R-1
The pressure groove 27R-2 is divided into a second pressurizing groove 27R-2 that is formed from the position where the vane 8 passes the maximum protrusion position to the opening position of the discharge hole 10.

Next, its effect will be explained. The lubricating oil stored in the reservoir 18 is sent to the bearing chamber 23 via the passage 24, the annular groove 25, and the passage 26 through the discharge pressure in the separation chamber 15, and has the effect of lubricating the bearing 20R and also lubricates the bearing 20R. 2
The lubricating oil that lubed 0R is the rear side plate 3R.
The lubricating oil is fed into the first pressure groove 27R-1 and the second pressure groove 27R-2 through a small gap formed between the rear end surface of the rotor 5 and the rear end surface of the rotor 5. Since the inside of the second pressure groove 27R-2 is substantially close to the discharge pressure, the pressure inside the second pressure groove 27R-2 is substantially close to the discharge pressure. -2, but is directly sent into the first pressurizing groove 27R-1. The lubricating oil sent into the first pressurizing groove 27R-1 accounts for most of the oil volume maintenance as the volume of the back pressure chamber 7a increases by the amount that the vane 8 protrudes toward the cylinder chamber 6 during the suction stroke. At the same time as replenishing the volume, the amount of replenishing oil is made to quickly follow the increasing speed associated with the vane protrusion speed, and a portion of the high pressure lubricating oil pushed out from the back pressure chamber 7b on the compression stroke side flows into the third pressure groove. It is replenished under reduced pressure at 27F-3. Therefore, the pressure in the vane back pressure chamber 7a on the suction stroke side is reduced from the first and third pressurizing grooves 27R-1 and 27F-3 into which the vane 8 flows as the volume of the back pressure chamber 7a expands. The pressure generated by the amount of lubricating oil sent in, that is, the first pressure groove 27R-1 and the third pressure groove 2
7F-3, and the pressure is smaller than the pressure in the vane back pressure chamber 7b on the compression stroke side, making it possible to prevent excessive back pressure from being applied to the vane 8. It is possible to keep the degree of wear of the parts low and also to reduce the driving resistance.

In addition, the back pressure in the back pressure chamber 7b on the compression stroke side decreases as the volume of the back pressure chamber 7b decreases by the amount that the vane 8 is pushed toward the back pressure chamber 7b.
The lubricating oil in the pressure groove 27R-2 is trapped and becomes high pressure, but a part of the lubricating oil in the third pressure groove 27F-3 is pushed out by the force of pushing out the lubricating oil in the back pressure chamber 7b. 1 pressure groove 27R-1 side, and prevents the lubricating oil in the back pressure chamber 7b from being completely trapped,
The pressure inside the back pressure chamber 7b is maintained at a higher pressure than the pressure in the back pressure chamber 7a on the suction stroke side, and as shown by the dashed line A in FIG. 9, the back pressure exceeds the pressure applied to the vane tip in the compression stroke. You can get it. By obtaining the effect of increasing the pressure inside the second pressure groove 27R-2 in this way, the vane 8
It is possible to prevent a lack of back pressure against the vibration, thereby preventing the occurrence of chattering.

The third pressurizing groove 27F-3 extends from the opening position of the suction hole 14 (starting end of the cylinder chamber 6) to the discharge hole 1.
Since the vane 8 is continuously provided all the way to the opening position 0 (the end of the cylinder chamber 6), the vane 8 is connected to the cylinder chamber 6 during the suction stroke.
Due to this, as the volume of the back pressure chamber 7a increases, a portion of the lubricating oil on the compression stroke side flows into the suction stroke side, thereby causing the third pressure groove 27F-3 to flow into the suction stroke side. It has the effect of equalizing the internal pressure. That is, the pressure in the third pressure groove 27F-3 is equal to the pressure in the second pressure groove 27F-3.
The pressure in the pressure groove 27R-2 is not as high as that in the pressure groove 27R-2, and the relationship of second pressure groove 27R-2>third pressure groove 27F-3>first pressure groove 27R-1 is established.

When such a relationship is established, the lubricating oil flows into the second pressure groove 27R-2 due to the pressure difference.
A flow occurs from the back pressure chamber 7b on the compression stroke side → the third pressure groove 27F-3 → the back pressure chamber 7a on the suction stroke side → the first pressure groove 27R-1, and the lubricating oil flows into the back pressure chamber 7a, 7b inside both side plates 3F, 3
By obtaining the effect of flowing across R,
Lubrication between the vane grooves 7 and the vanes 8 can be smoothly performed, and the vanes 8 can slide even more smoothly within each vane groove 7. In addition, as the back pressure P1 of the back pressure chamber 7a in the suction stroke, a pressure state is obtained in which the pressure in the first pressure groove 27R-1 and the pressure in the third pressure groove 27F-3 are averaged, and , the back pressure P2 of the back pressure chamber 7b in the compression stroke is the second pressurizing groove 27R-2.
A pressure state is obtained in which the pressure inside and the pressure inside the third pressure groove 27F-3 are averaged. (However, P1<P2).

On the other hand, in the above embodiment, the first pressure groove 27R
−1 and the second pressure groove 27R-2, the reservoir 18
The lubricating oil supplied to the bearing chamber 23 through the passage 24, the annular groove 25, and the passage 26 is supplied through the gap formed between the rear side plate 3R and the end face of the rotor 5 (that is, through the "throttle"). However, it is also possible to directly supply lubricating oil to the second pressurizing groove 27R-2 without passing through the "throttle" as described above. By directly supplying the second pressure groove 27R-2 in this manner, it is possible to more reliably prevent chattering even when the discharge pressure in the compression stroke is high.

Effects of the invention The invention is constructed as described above.
As mentioned above, among the pressurizing grooves provided on the front side plate and the rear side plate facing the back pressure chamber on the rotor side, the pressurizing groove formed on one of the side plates corresponds to the suction stroke and the compression stroke. Two pressure grooves (first pressure groove and second pressure groove)
The pressure groove (third pressure groove) formed in the other side plate is continuously provided from the starting end to the terminal end of the compression chamber, thereby reducing the compression stroke. It is possible to apply high back pressure, which prevents the occurrence of chattering, and also reduces the back pressure during the suction stroke, which reduces wear on the vane tip and drive resistance. I was able to do this. Moreover, in the case of the present invention, by making it possible to obtain a smooth flow of lubricating oil between the respective pressurizing grooves formed on the front side plate and the rear side plate,
This allows for smooth lubrication between the vanes and the vane grooves, which allows the vanes to move in and out smoothly, and reduces the degree of wear on the sliding parts. By being able to prevent lubricating oil from being trapped in the back pressure chamber, in other words, by allowing some of the lubricating oil in the back pressure chamber to escape into the third pressure groove, abnormal increases in back pressure can be prevented. can be relieved,
This has made it possible to prevent an increase in driving resistance and also to prevent abnormal wear of the vanes.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view of a slide vane rotary compressor, Fig. 2 is a sectional view of the front side plate portion, and Fig. 3 is a sectional view of the rear side plate portion.
Fig. 4 is an enlarged sectional view of the bearing portion of the rear side plate, Fig. 5 is a sectional view of the pressurizing groove portion formed in the front side plate and rear side plate, Fig. 6 is a front view of the same, and Fig. 7 is the conventional structure. 8 is a front view of the same, FIG. 9 is a graph showing a comparison of back pressure with the conventional structure, and 1.
FIG. 0 is a side sectional view of the conventional structure, and FIG. 11 is a sectional view of the rear side plate portion. 1...Housing, 1F...Front housing, 1R...Rear housing, 2...Cylinder block, 3F...Front side plate, 3
R...Rear side plate, 4...Rotor shaft,
5... Rotor, 6... Cylinder chamber, 7... Vane groove, 7a... Back pressure chamber, 8... Vane, 9...
Discharge chamber, 10... Discharge hole, 11... Discharge valve, 13
... Suction chamber, 14 ... Suction hole, 15 ... Separation chamber,
18...Reservoir part, 20F, 20R...Bearing, 21F, 21R...Bearing part, 22...Bearing cover, 23...Bearing chamber, 24...
Passage, 25... Annular groove, 26... Passage, 27F,
27R...pressure groove, 27R-1...first pressure groove,
27R-2...Second pressure groove, 27F-3...Third
Pressure groove.

Claims (1)

[Scope of utility model registration request] Pressurizing grooves are carved in the front side plate and rear side plate in correspondence with the rotation locus of the back pressure chamber formed at the bottom of the vane groove extending in the radial direction between the front and rear end surfaces of the rotor. One pressure groove is provided continuously from the opening position of the suction hole to the opening position of the discharge hole, and the other pressure groove is provided continuously from the opening position of the suction hole to the maximum position of the vane. A slide vane type rotary compression system that is divided into a pressure groove that extends from just before the protrusion position and a pressurization groove that extends from just after the maximum protrusion position of the vane to the opening position of the discharge hole. Back pressure applying mechanism in the machine.