JPH0312679B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to the refueling of vane rotary compressors driven by drive sources such as automobile engines that are frequently started and stopped and may be started at low speeds. It is related to the device.

Conventional configuration and its problems As is well known, in vane rotary compressors,
A structure is used in which high-pressure lubricating oil is applied to the rear end of the vane so that as the rotor rotates, the vane always rotates and slides with its tip in contact with the inner wall of the cylinder.

One way to achieve this is to create a passage that communicates between the inside of the high-pressure sealed case and the oil supply groove provided on the side of the rotor, and by supplying oil to the back space of the vane using differential pressure, the rear end of the vane is pressed. The oil supply groove is partially separated to cut off oil supply to the space behind the vane so as to prevent the vane tip from separating from the cylinder inner wall at the boundary between high pressure gas and low pressure gas (axial seal point). Some types have such a structure that the vane tip is always in contact with the inner wall of the cylinder during operation and can rotate and slide.

For example, if we consider the case where the above-mentioned conventional compressor is used in an automobile refrigeration cycle, the compressor is driven by the engine, but since the rotational speed of the engine changes over a wide range (600 rpm to 6000 rpm), the compressor The rotation speed also varies over a wide range. On the other hand, a refrigeration cycle consists of a compressor, a condenser, a liquid receiver, an expansion valve, and an evaporator connected by piping. Due to leakage from a discharge valve provided in a discharge hole opening into the space, the entire refrigeration cycle becomes pressure-equalized over time after the compressor is stopped. In addition, it usually takes about 1 to 2 hours to reach an equal pressure state, so it is possible that the entire interior of the compressor will often reach an equal pressure state under extremely normal usage conditions. state.

However, in the conventional compressor, as mentioned above, oil is supplied to the space behind the vane using the pressure difference inside the compressor, so if the refrigeration cycle is in an equal pressure state 1 to 2 hours after the compressor is stopped, When the compressor is started, the back of the vane is not sufficiently lubricated, and as a result, the vane comes loose from the inner wall of the cylinder and is forced into the vane slot, resulting in poor compression.

Of course, in this case, centrifugal force acts on the vane in the direction of extension depending on its rotational speed, but this effect is extremely small at low rotational speeds (for example, below 1000 rpm), so there is a possibility that the vane will be activated at low rotational speeds. In many compressors for automobile refrigeration cycles, the effect of centrifugal force cannot be expected.

OBJECTS OF THE INVENTION One of the objects of the present invention is to eliminate the drawbacks found in the conventional compressors mentioned above, and to enable stable operation even when starting from an equal pressure state.

Structure of the Invention In order to achieve this object, the present invention provides two vane back spaces that are adjacent to each other with an axial seal point in between, that is, a vane back space of a vane in an extension stroke and a vane back space of a vane in a retraction stroke. A groove is provided to communicate with the

With this configuration, by supplying the oil in the vane back space of the vane in the retraction stroke to the vane back space of the vane in the extension stroke, the compressor can maintain a stable state even when starting from an equal pressure state. It is designed to allow you to drive.

DESCRIPTION OF EMBODIMENTS The present invention will be described below with reference to the accompanying drawings, FIGS. 1 and 2, which show one embodiment of the invention.

In the figure, 1 is a cylinder having a cylindrical inner wall, the center of which is eccentrically located with respect to a drive shaft 2 that transmits power from the outside. 3 is inside the cylinder 1, and part of its outer circumferential surface is always inside the cylinder 1.
The rotor is disposed so as to form a minute gap between the inner wall of the rotor and the axial seal point 4, and is formed integrally with the drive shaft 2. A plurality of vane slots 5, 5a, and 5b are provided in the rotor 3 and are opened in the outer peripheral surface of the rotor 3 in parallel with the axis of the drive shaft 2. 6, 6a, 6b are vane slots 5, 5 respectively
It is a plate-shaped vane that is inserted into and out of the vanes a and 5b, and the rear end and the vane slots 5, 5a and 5b form vane back spaces 20, 20a and 20b. Reference numerals 7 and 8 denote a front side plate and a rear side plate, each of which is provided with a bearing 9 that closes both ends of the cylinder 1 and rotatably supports the drive shaft 2. A space 10 is formed. 11 is a suction hole provided in the rear side plate 8 and opened to the low pressure side of the cylinder inner space 10; 12 is a discharge hole provided in the cylinder 1, with one end opening to the high pressure side of the cylinder inner space 10 and the other end opening to the high pressure chamber 14. It's a hole. 13 is a discharge valve provided in the discharge hole 12. Reference numeral 15 denotes a high-pressure case, the internal space of which communicates with the high-pressure chamber 14 through a passage 16, and has an oil reservoir below.
Reference numeral 17 denotes an oil supply groove provided in the rear side plate 8, which communicates with an oil reservoir in the high pressure case 15 through oil supply passages 18 and 19. The oil supply groove 17 also communicates with the vane back space 20. Reference numeral 21 denotes a groove provided in the rear side plate 8 separate from the oil supply groove 17, which is located in the vane back space 20a of the vane 6a that is in the extension stroke on the advancing side, sandwiching the axial seal point 4, that is, in the process of increasing its volume. Vane back space 20a
At the same time, the vane 6b in the retraction stroke on the lagging side communicates with the vane back space 20b, that is, the vane back space 20b in the middle of volume reduction, and immediately before the vane 6b passes the axial seal point 4, the vane back space 20b is connected to the vane back space 20b. 20b, and is configured to communicate with only two vane back spaces at the same time.

Next, the operation of the vane rotary compressor having the above configuration will be explained.

When the drive shaft 2 receives power from a drive source such as an engine and rotates in the direction of the arrow in FIG. 2, gaseous refrigerant flows into the cylinder 1 from the evaporator (not shown) of the refrigeration cycle through the suction hole 11. . The high-pressure refrigerant compressed as the rotor 3 rotates flows from the discharge hole 12 through the high-pressure chamber 14 into the high-pressure case 15, where lubricating oil is separated and the condenser of the refrigeration cycle (not shown) sent to The lubricating oil separated from the high-pressure refrigerant is stored in an oil reservoir below the high-pressure case 15, and is stored in the oil supply passage 1.
The oil is supplied into the vane back space 20 by differential pressure through the oil supply grooves 17 and 9 , 18 , and exerts a pressing action on the vanes 6 to press the tips of the vanes 6 against the inner wall of the cylinder 1 . Furthermore, vane 6 is at axial seal point 4.
The advantage of the conventional rotary compressor is that the vane back space 20 is made substantially independent just before passing, and the pressure inside the vane back space 20 is increased by retraction of the vane 6, thereby preventing the vane 6 from malfunctioning in a steady operating state. This is similar to the oil supply system.

On the other hand, when starting from an equal pressure state, the vane 6b is pushed into the vane slot 5b in contact with the inner wall of the cylinder 1 due to the rotation of the rotor 3, and at the same time, the refrigerant is discharged from the discharge hole 12 and the oil in the vane back space 20b is is supplied to the vane back space 20a of the advancing vane 6a through the groove 21, exerts a pressing action on the back of the vane 6a, and presses the tip of the vane 6a against the inner wall of the cylinder 1.

Therefore, by sequentially supplying oil to the back spaces of the vanes on the advancing side through the grooves 21, the direction of rotation of the vanes changes. In other words, after passing through the axial seal point 4 where the acceleration is maximum, a sufficient pressing action can be exerted on the vane, so that the amount of refrigerant discharged is small, and the pressure within the high pressure case 15 is not sufficiently increased. Even at startup, when the differential pressure between the pressure in the vane back space 20 and the pressure in the vane back space 20 is extremely small, normal operation of the compressor can be enabled.

Note that immediately after the compressor is stopped, the pressure in the vane back space 20 is higher than the tip of the vane 6, so
The vane 6 is in a state of being pressed against the inner wall of the cylinder 1. Even if the pressure reaches an equalized state after a certain period of time has passed after stopping, the forces that the vane 6 receives are the pressure and gravity at the tip and rear end of the vane 6, so if the number of vanes is two or more, at least one The vane 6 is in a state of being pressed against the inner wall of the cylinder 1.

Note that FIGS. 3 and 4 show other embodiments of the present invention, and in the same figures, parts with the same reference numerals as those in the embodiments shown in FIGS. It shows the same member having the same function as . In the embodiment shown in FIGS. 3 and 4, two separate grooves 21 are provided in the rear side plate 8, and these two grooves 21 are connected by two passages 22 and a groove 23. However, it is clear that the same effects as in the previous embodiment can be obtained.

Furthermore, FIG. 5 shows still another embodiment of the present invention, and in this figure, parts given the same reference numerals as in the previous embodiments are the same parts having the same functions as in the previous embodiments. It shows a member. In another embodiment shown in FIG.
It is provided with two grooves 21 that communicate through the
It is clear that the same effects as in the previous embodiments can be obtained.

Further, it is clear that in each of the embodiments, the same effect can be obtained even if the grooves provided in the rear side plate are provided in the front side plate or both, or even if the number of vanes is different.

Effects of the Invention As is clear from the above embodiments, the vane rotary compressor oil supply device of the present invention communicates the vane back space with one or both of the front side plate and the rear side plate of the compressor body through the rotation of the rotor. A vane rotary compressor is constructed by providing an oil supply groove and communicating the oil supply groove with a high-pressure oil reservoir to apply high pressure to the rear end of the vane so that the vane protrudes. and one or both of the rear side plates, sandwiching the axial seal point to communicate the vane back space of the leading side vane that is in the middle of the extension stroke and the vane back space of the lag side vane that is in the middle of the retracting stroke. This groove is formed separately from the oil supply groove and communicates with only up to two spaces at the back of the vane at the same time, so even when the compressor starts up from an equal pressure state, it will not work properly. Compression action can be started and stable operation can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a vane rotary compressor equipped with an oil supply device showing one embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the - line of FIG. 1, and FIG. A vertical cross-sectional view of a vane rotary compressor equipped with an oil supply device showing an embodiment, FIG. 4 is the same as in FIG.
5 is a longitudinal sectional view of a vane rotary compressor equipped with an oil supply device showing still another embodiment of the present invention. 1... Cylinder, 3... Rotor, 4... Axial seal point, 5, 5a, 5b... Vane slot, 6, 6a, 6b... Vane, 7... Front side plate, 8... Rear side plate, 10 ...Space inside the cylinder,
12...Discharge hole, 15...High pressure case, 17...
Oil supply groove, 18, 19... Oil supply passage, 20, 20
a, 20b... Vane back space, 21... Groove.

Claims (1)

[Claims] 1 A cylinder having a cylindrical inner wall, a rotor disposed within the cylinder such that a part of its outer peripheral surface always forms a minute gap between the inner wall of the cylinder and the axial seal point, and a plurality of rotors provided on the rotor. a plurality of vanes that are inserted into and out of the vane slot so that their tips abut against the inner wall of the cylinder; a front side plate that rotatably supports the rotor and closes both end surfaces of the cylinder to form an internal cylinder space; A compressor main body is constituted by a rear side plate and a high pressure case that communicates with a discharge hole opening into the cylinder interior space and has an oil reservoir section below, and the vane slot and the vane are provided in at least one of the front side plate and the rear side plate. An oil supply groove is provided which communicates with the back space of the vane formed by the rear end of the vane through rotation of the rotor, and this oil supply groove communicates with an oil reservoir below the high pressure case to transfer high pressure from the high pressure case to the rear end of the vane. A refueling passage is provided in addition to the oil supply passageway for causing the vane to protrude, and at least one of the front side plate and the rear side plate is provided with a lubrication passage for the vane of the advancing side vane which is in the middle of the extension stroke of the adjacent one, sandwiching the axial seal point. A groove is provided to communicate the back space with the vane back space of the lagging side vane in the middle of the retracting stroke, and the length of this groove is formed separately from the oil supply groove, and the vane back space is formed in up to two locations. A vane rotary compressor oil supply system with a length that does not communicate at the same time.