JPS647231B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention provides a rotor having a plurality of retractable vanes arranged eccentrically within a rotating sleeve, and synchronously rotating the rotor and the rotating sleeve. The present invention relates to a rotary compressor with a rotary sleeve that compresses air by sequentially changing the volume of an air chamber partitioned by each vane.

(Prior Art) This type of rotary compressor with a rotary sleeve has a casing constructed by attaching side housings 52 and 53 to both sides of a center housing 51 having a cylindrical inner peripheral surface 51a, as shown in FIG. A cylindrical rotating sleeve 55 is rotatably fitted into the rotating sleeve 50 .
A rotor 58 in which a plate-shaped vane 56 is removably fitted in a slit-shaped vane groove 57 formed in the radial direction is arranged eccentrically within the rotor 58, and the frictional force between the vane and the rotating sleeve 55 is reduced. The rotor 58 and rotating sleeve 55 are rotated synchronously to fluidly change the volume of the air chamber 59 surrounded by the rotating sleeve 55, rotor 58, and vane 56, thereby sucking and compressing air. , is configured to perform a discharging action.

In this case, the compressed air discharge port 54
is usually formed only on one side of the two side housings (the side housing 52 in the case shown in Fig. 3) (if the suction port is also formed on the side housing on the same side as the discharge port) ).

However, if the discharge port 54 is formed only in one side housing 52 of the two side housings, as will be described in detail later, the vane 56 will wear unevenly in a tapered shape in the longitudinal direction, and the rotating sleeve 55 and center housing 51
between each other and the vane 56 and the side housing 52,
Seizing occurs between the vanes 53 and the vanes 56
This causes a problem that pitching occurs.

That is, when the vane 56 moves upward and downward within the vane groove 57 as the rotor 58 rotates, the pump is pumped in the bottom cavity S of the vane groove 57 by the lower surface 56b of the vane 56. action is taken. At this time, pressurized air flows out to the discharge port 54 side due to the pumping action of the vane 56, but the void portion S 2 located far from the discharge port 54 in the vane groove bottom void S ₂ In this case, the pressurized air cannot flow out smoothly, and therefore, in the hollow part _S2 , there is always another hollow part (the hollow part near the discharge port 54).
S ₁ ). That is, there is always P between the air pressure (vane back pressure) P ₁ in the cavity part S ₁ on the side close to the discharge port 54 and the vane back pressure P ₂ in the cavity part S ₂ on the side far from the discharge port 54. The relationship ₁ < P ₂ occurs (unequal vane back pressure). Therefore, due to the unevenness of the vane back pressure, the contact pressure between the vane 56 and the rotating sleeve 55 is higher on the side opposite to the discharge port 56B than on the side opposite to the discharge port 56B.
6A side (uneven contact pressure), and during long-term use, the vane 56 gradually becomes unevenly worn in a tapered shape in the longitudinal direction as shown by the chain line (reference numeral 56').

Therefore, the longitudinal end surface 56c of the vane 56,
56d is lower than that of each side housing 52, 53 than in the normal state where uneven wear has not occurred on the vane 56.
When the vane end faces 56c, 56d come into contact with the side housings 52, 53, seizure occurs between them, and the vane 56 protrudes from the side housings 52, 53 at its protruding corner. A problem arises in that the vane 56 causes pitting due to point contact.

Furthermore, as mentioned above, the fact that the air cannot flow out smoothly in the bottom cavity S of the vane groove means that the retracting movement of the vane 56 is inhibited and the contact pressure of the vane 56 against the rotating sleeve 55 is increased. As a result, as the rotor 58 rotates, the rotating sleeve 55 is gradually pressed from its normal rotational position to the compressed side wall surface of the center housing 51 and comes into strong contact with the wall surface of the center housing 51, causing seizure between the two. become.

Furthermore, although this is generally the case in a rotary compressor configured such that the lower surface 56b of the vane 56 performs a pumping action in the bottom cavity S of the vane groove 57, for example, the pumping action of a specific vane may If pressurized air flows into the suction port side, the suction efficiency of the rotary compressor will be reduced.

In other words, the air pressurized by the pumping action of the vanes is heated by the compression action of the rotary compressor, and then further raised by the pumping action of the vanes, resulting in a considerably high temperature and a large volumetric expansion. . Therefore, when such high-temperature and volume-expanding air flows into the intake port side, the volume expansion of this inflow air itself and
Due to the synergistic effect with the volumetric expansion of the original intake air, which is heated by contact with the incoming air, the intake efficiency as a rotary compressor is substantially reduced. Therefore, when taking countermeasures against the pumping effect of the vanes, it is necessary to fully consider the problem of a decrease in suction efficiency.
The reason why the air pressurized by the pumping action of the vanes in the empty space on the discharge port side easily flows into the air chamber on the suction port side is because the air chamber on the discharge port side has a high internal pressure, but the air chamber on the suction port side has a high internal pressure. The internal pressure of the side air chamber is low, and therefore the pressurized air in the space located on the discharge port side flows into the air chamber on the suction port side more easily than the air chamber on the discharge port side.

(Object of the Invention) In view of the problems pointed out in the above-mentioned section of the prior art, the present invention aims to solve the problem of increasing the back pressure of the vanes moving in and out of the vane grooves of the rotor without causing a decrease in the suction efficiency of the rotary compressor. While suppressing the back pressure, the back pressure is made as equal as possible over the entire length of the vane in the longitudinal direction, thereby preventing seizure and vane pitting between the vane and the side housing and between the rotating sleeve and the center housing. This is intended to improve the durability of the compressor as a whole.

(Means for Achieving the Object) As a means for achieving the above-mentioned object, the present invention provides a buffer that is independently formed in each cavity formed by the vane groove and the lower surface of the rotor and inside the rotor. The pumping volume is increased by the buffer chamber at least on the side opposite to the discharge port, thereby suppressing the rise in vane back pressure itself, and the This also attempts to suppress unevenness in vane back pressure.

(Function) In the present invention, the above means suppresses the increase in vane back pressure itself, and equalizes the vane back pressure as much as possible in the longitudinal direction of the vane regardless of the distance from the discharge port. This prevents tapered uneven wear in the longitudinal direction of the vane, thereby preventing seizure between the vane and the side housing and pitting of the vane, and further reducing the contact pressure between the vane and the rotating sleeve. This also prevents seizure between the rotating sleeve and the center housing since the radial displacement of the rotating sleeve is reduced.

In addition, each buffer chamber is formed independently inside the rotor, and is communicated with each cavity at least on the side opposite to the discharge port, so that air pressurized by the pumping action of the vanes passes through the buffer chamber. This prevents the air from flowing into the air space of another vane located on the suction port side, and from the air space flowing into the air chamber on the suction port side through the gap between the vane and the vane groove. Become.

Furthermore, as described above, each buffer chamber is provided independently inside the rotor and is communicated with each of the corresponding chambers, so that the air pressurized by the pumping action of the vane is transferred to the rotor. When the is located on the suction port side and moves in the protrusion direction from the vane groove, it acts to press the lower surface side of the vane and promote the protrusion movement of the vane, so that when the vane protrudes, the lower surface side of the vane This prevents negative pressure from forming and obstructing the protrusion movement.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described with reference to FIGS. 1 and 2.

(a: Configuration) FIG. 1 shows a rotary compressor Z according to an embodiment of the present invention.
It is shown. This rotary compressor Z is used as a supercharger for an automobile engine, and includes a center housing 2 having a cylindrical inner circumferential surface 2a and a pair of parts fastened to both sides of the center housing 2. side housing, that is, intake ports 21 at appropriate intervals in the circumferential direction (see Fig. 2).
The casing 1 includes a first side housing 3 having a discharge port 22 formed therein, and a second side housing 4 having neither an intake port nor a discharge port.

A cylindrical rotating sleeve 5 and a rotor 6, which will be described later, are fitted into the casing 1.

The rotating sleeve 5 is attached to the center housing 2
It has an outer diameter smaller than the inner diameter dimension by an appropriate dimension, and when it is rotatably fitted concentrically in the casing 1, the inner circumferential surface 2a of the casing 1 and the outer circumferential surface 5a of the rotary sleeve 5 An air bearing chamber 14 of an appropriate size is formed between the two. The air bearing chamber 14 is connected to the first side housing 3 through an air passage 16 consisting of an air hole 16a formed in the center housing 2, an air chamber 16b, and a communication passage 16c formed in the first side housing 3. The rotary sleeve 5 is connected to the exhaust port 22, and the rotary sleeve 5 is rotatably supported in a floating state by pressurized air introduced into the air bearing chamber 14 (air bearing action).

The rotor 6 has a rotor body 11 integrally formed with a hollow cylinder as shown in FIGS. 2 side housing 4
The rotary sleeve 5 is eccentrically disposed within the rotary sleeve 5, with the rotary sleeve 5 being rotatably supported.
The rotor body 11 of the rotor 6 has a vane groove 1 of an appropriate depth extending in the radial direction as shown in FIG.
2, 12... are formed at equal intervals in the circumferential direction. These vane grooves 12, 12... are formed in such a manner that the circumferential wall 11a of the rotor main body 11 is depressed in the radial direction, and the inside of the rotor main body 11 is defined by these vane grooves 12, 12... in the circumferential direction. Buffer room 8,8 consists of four vacant rooms lined up in
It is divided into... Furthermore, this buffer chamber 8, 8...
is the rotor rotational direction (arrow R direction) of the two vane grooves 12, 12 located on both sides, respectively.
Groove wall 1 of vane groove 12 located on the leading side
Two communication holes 23 on the left and right are provided through the holes 2a near both ends in the rotor axial direction and at positions facing the bottom cavity 19 of the vane groove 12 (that is, the portion of the vane groove 12 closer to the groove bottom than the vane bottom surface 7b). , 23 to the bottom cavity 19.

Further, plate-shaped vanes 7, 7, . . . are fitted into the vane grooves 12, 12, . . . so as to be freely retractable. When the rotor 6 rotates, each of the vanes 7, 7, .
1 and 4 air chambers divided in the circumferential direction between 1 and 1.
7A, 17B, 17C, and 17D are formed.

(b: Operation and its effect) Next, to briefly explain the operation and its effect of the rotary compressor Z, when the rotor 6 is rotationally driven by an engine, a motor, etc., each vane groove 12 of the rotor 6, Each vane 7, 7 in 12...
... protrudes outward due to centrifugal force, and their upper surfaces 7a, 7a... contact the inner surface 5b of the rotating sleeve 5, so that the rotating sleeve 5 is moved through the vanes 7, 7... by the frictional force between them. The rotor 6 is rotated synchronously with the rotor 6. By synchronously rotating the rotor 6 and the rotating sleeve 5, which are arranged eccentrically with respect to each other in this way, through the respective vanes 7, 7..., the volume of each air chamber 17A, 17A... is sequentially changed, and the intake port 21 The air sucked in is pressurized and discharged from the discharge port 22. At this time, a part of the discharged air was introduced into the air bearing chamber 14 of the casing 1 through the air passage 16, and the rotating sleeve 5 was maintained in a non-contact state with the inner circumferential surface 2a of the center housing 2 due to the air bearing action. It is forced to rotate at high speed.

On the other hand, as the rotor 6 rotates, each vane 7, 7
... respectively move in and out of the respective vane grooves 12, 12..., and a pumping action occurs on the lower surface side 7b of each of the vanes 7, 7....

However, in this embodiment, the bottom cavities 19, 19 of each vane groove 12, 12... are connected to the corresponding buffer chamber 8 through the two communication ports 23, 23 by applying the present invention. , 8... As described later, in the discharge zone where the vane groove 12 communicates with the discharge port 22 side,
The increase in the back pressure of the vane 7 is suppressed and the back pressure is made as equal as possible in the longitudinal direction, thereby preventing radial displacement of the rotating sleeve 6 and uneven wear of the vane 7. is suction port 2
In the suction zone communicating with side 1, vane 7
The contact pressure with respect to the rotary sleeve 5 is maintained at an appropriate value, and the volumetric efficiency of the rotary compressor Z is improved. That is, in the discharge zone, since the vanes 7 are pushed into the vane grooves 12 as the rotor 6 rotates, the air on the bottom surface 7b side of the vanes 7 is pumped by the vanes 7, and the air that would otherwise be The back pressure on the vane 7 will increase.
However, in this embodiment, the bottom cavity 19 of the vane groove 12 is communicated with the buffer chamber 8 having a relatively large volume through the communication ports 23, 23 by applying the present invention. Since the pumping volume is increased by the buffer chamber 8 and an increase in vane back pressure is suppressed, misalignment of the rotating sleeve 6 is reduced as much as possible, and the discharge port side of the vane groove bottom cavity 19 is Since the side opposite to the discharge port is communicated with each other via the buffer chamber 8, the unevenness of the vane back pressure between the two can be caused by the case where such a buffer chamber 8 is not provided (conventional example)
Therefore, tapered uneven wear in the longitudinal direction of the vane 7 caused by uneven vane back pressure can be reduced as much as possible.

On the other hand, in the suction zone, as the rotor 6 rotates, the vanes 7 are pushed out from the vane groove 12 toward the rotating sleeve 5 side by centrifugal force. Negative pressure is generated in the bottom cavity 19 of the rotary compressor Z, inhibiting the ejecting action of the vane 7, and the lack of contact pressure between the vane 7 and the rotary sleeve 5 impairs the sealing performance between the two, reducing the volumetric efficiency of the rotary compressor Z. will decrease. In addition, such insufficient contact pressure between the vane 7 and the rotating sleeve 5 eventually causes the rotating sleeve 5 to be biased toward the discharge zone side of the center housing 2, causing seizure between the two. .

However, in this embodiment, since the bottom cavity 19 of the vane groove 12 is communicated with the buffer chamber 8 as described above, the pressurized air introduced into the buffer chamber 8 in the discharge zone flows into the suction zone. from the buffer chamber 8 to the bottom cavity 1 of each vane groove 12.
9 and the pressure increase in the bottom cavity 19 maintains the contact pressure of the vane 7 against the rotating sleeve 5 at a proper value. As a result, the volumetric efficiency is maintained well and the deviation of the rotating sleeve 5 toward the center housing 2 side is reduced as much as possible.

In the above embodiment, the buffer chamber 8 and the bottom cavity 19 of the vane groove 12 are made to communicate with each other on both the discharge port side and the side opposite to the discharge port, but the present invention is not limited to this. However, in a case where the discharge port 22 is provided only on one of the pair of side housings, the buffer chamber 8 and the bottom cavity 19 of the vane groove 12 are communicated with each other at least on the side opposite to the discharge port. In this way, even when the buffer chamber 8 and the bottom cavity 19 of the vane groove 12 are communicated only on the side opposite to the discharge port, the same effect as in the above embodiment is applied (although there are differences in degree). The effect of suppressing the increase in vane back pressure and the imbalance of the vane back pressure in the longitudinal direction of the vane can be obtained.

Moreover, since each buffer chamber 8, 8... is formed independently inside the rotor and communicates with each bottom cavity 19, 19... at least on the side opposite to the discharge port, the vane 7 on the discharge port side Air pressurized by the pumping action flows from the bottom cavity 19 through the buffer chamber 8 into the bottom cavity 19 of the vane on the suction port side, and from the bottom cavity 19 flows into the vane 7 and the vane groove 12. This prevents the air from flowing into the air chamber on the suction port side through the gap. Therefore, it is possible to prevent the suction efficiency of the rotary compressor from decreasing due to the volumetric expansion of the inflowing air itself and the volumetric expansion of the normal intake air whose temperature is raised by the temperature of the inflowing air. It is.

(Effects of the Invention) The present invention provides a casing having a center housing having a cylindrical inner peripheral surface and a pair of side housings disposed on both sides of the center housing, and one of the pair of side housings. a discharge port formed in a side housing, a rotating sleeve rotatably fitted in the center housing, a rotor eccentrically disposed within the rotating sleeve, and a plurality of vanes provided in the radial direction of the rotor. In a rotary compressor equipped with a plurality of vanes that are respectively fitted into grooves so as to be freely protrusive and retractable and are in sliding contact with the inner peripheral surface of the rotary sleeve, each cavity formed by the vane groove of the rotor and the lower surface of the vane and the inside of the rotor. The invention is characterized in that the buffer chambers and the buffer chambers formed independently are communicated with each other at least on the side opposite to the discharge port.

Therefore, according to the present invention, since the contact pressure between the vane and the rotating sleeve is properly maintained on both the low pressure side and the high pressure side, it is possible to prevent the rotating sleeve from coming into contact with the center housing due to misalignment of the rotating sleeve. This has the effect of preventing seizure between the rotating sleeve and the center housing.

Furthermore, since tapered uneven wear in the longitudinal direction of the vane is suppressed as much as possible by equalizing the back pressure of the vane, contact between the longitudinal end surface of the vane and the inner surface of the side housing is prevented as much as possible. As a result, seizure between the vane and the side housing and pitting of the vane can be prevented.

In addition, since each independently provided buffer chamber is communicated with a cavity formed on the lower surface side of the corresponding vane, the cavity on the discharge port side is pressurized by the pumping action of the vane. Air does not flow into the air chamber on the suction port side and then into the air chamber on the suction port side, so the suction efficiency of the rotary compressor is maintained well, and the air space on the discharge port side is connected to the suction port. When located on the side, the pushing force of the pressurized air in the space promotes the protrusion of the vane, and the effect of making the contact pressure of the vane against the rotating sleeve as uniform as possible can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the main parts of a rotary compressor according to an embodiment of the present invention, Fig. 2 is a longitudinal sectional view of the main parts of Fig. 1, and Fig. 3 is a longitudinal sectional view of the main parts of a rotary compressor with a conventional structure. be. 1...Casing, 2...Center housing,
3, 4...Side housing, 5...Rotating sleeve,
6... Rotor, 7... Vane, 8, 38... Buffer chamber, 1
0... Rotor shaft, 12... Vane groove, 21... Intake port, 22... Discharge port, 23... Communication hole.

Claims (1)

[Claims] 1. A casing having a center housing having a cylindrical inner circumferential surface and a pair of side housings disposed on both sides of the center housing;
A discharge port formed in one of the pair of side housings;
A rotary sleeve rotatably fitted in the center housing, a rotor eccentrically disposed within the rotary sleeve, and a rotor fitted retractably into a plurality of vane grooves provided in the radial direction of the rotor. A rotary compressor comprising a plurality of vanes slidingly in contact with the inner circumferential surface of the sleeve, each space formed by a vane groove of the rotor and the lower surface of the vane, and each buffer independently formed inside the rotor. A rotary compressor characterized in that the chambers are communicated with each other at least on the side opposite to the discharge port.