JPS61164093A - Vene-type rotary compressor - Google Patents

Abstract

PURPOSE:To make liquid compression in time of starting a compressor preventable, by installing an oil return passage, interconnecting a bottom part and an oil sump of a cylinder chamber, in an opening end part at the oil sump side of a lubricating oil passage as well as installing a block valve, which opens only at a time when discharge pressure in the compressor is low, in the oil return passage. CONSTITUTION:On a bottom part of a cylinder (b) for a vane-type compressor, there is provided with an oil return passage 39 which puts lubricating oil stayed behind inside the cylinder back to an oil sump 34. On the other hand, an opening part at the oil sump side of the oil return passage 39 is installed concentrically with an opening of an oil feed passage 36, and in addition, a block valve 41, which opens only at a time when discharge pressure in the compressor is low, is installed in the opening part of the oil return passage 39. Therefore, when the discharge pressure in the compressor is low as in time of compressor starting, the cylinder chamber (b) and the oil sump 34 are interconnected with each other so that owing to the lubricating oil stayed behind inside the cylinder, no liquid compression occurs there.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a vane-type rotary compressor, and particularly to a vane-type rotary compressor in which back pressure is applied to a vane member using lubricating oil.

<Prior art> In a vane-type rotary compressor, the compression efficiency decreases due to the vane member rising from the cylinder wall surface, or the pressure of the pressurized fluid acting on the vane member changes drastically as the discharge stroke ends. In order to avoid chatter caused by collision between the vane member and the cylinder wall surface, pressurized lubricating oil is introduced into the vane groove to apply back pressure to the vane member. It has been known. Furthermore, lubricating oil is supplied to, for example, a bearing part using the discharge pressure of the compressor, and lubricating oil that has lubricated the bearing is supplied to the bottom of the vane groove from either the front or rear of the rotor, or either of them (III).
II structure is also conventionally known.

According to this type of lubrication structure, the structure for supplying lubricating oil can also be used to apply back pressure to the vane member, and there is an advantage that a separate pump is not required for this purpose. However, when the compressor is stopped, the differential pressure between the residual pressure on the discharge side and the internal pressure in the intermediate compression chamber causes I! l Lubricating oil accumulates in the intermediate compression chamber at the bottom of the cylinder, causing a lack of lubricating oil in various parts when restarting the compressor, resulting in poor lubrication and chattering of the vane members, as well as incompressible lubricating oil. This may cause damage to the vane members and other compressor parts.

JP-A No. 56-129795 discloses a structure in which a check valve is provided at the bottom of the cylinder chamber, but when attempting to provide an oil passage for lubricating the bearing at the front end of the rotor shaft, The structure is complicated, making it difficult to downsize the compressor, and the manufacturing process tends to become complicated.

<Problems to be Solved by the Invention> In view of these drawbacks of the prior art, the main object of the present invention is to prevent lubricating oil from remaining excessively in the intermediate compression chamber even when the compressor is stopped. An object of the present invention is to provide an improved vane type rotary compressor.

<Means for Solving the Problems> According to the present invention, such an object is achieved by: a cylindrical cylinder chamber; a rotor having a vane groove on the outer periphery; In a vane rotary compressor comprising a vane member and a lubricating oil path communicating from an oil reservoir provided on the discharge side to the bottom of the vane groove, an oil return communicating the bottom of the cylinder chamber and the oil reservoir. A passage is provided concentrically with the opening end of the lubricating oil passage on the oil reservoir side, and a blocking valve that opens only when the discharge pressure of the compressor is low is provided in the oil return passage. This is achieved by providing a vane-type rotary compressor characterized by:

In this way, an oil return passage communicating between the bottom of the cylinder chamber and the oil reservoir is provided, and a blockage valve that responds to the discharge pressure is provided in the oil passage, so that the residual pressure of the discharge pressure is removed after the compressor is stopped. If the oil return passage is opened to the oil return passage at the point when the pressure has become so low, the lubricating oil accumulated in the intermediate compression chamber can be appropriately returned to the oil reservoir, and the above-mentioned disadvantages can be solved.

<Example> FIGS. 1 and 2 show a vane type rotary compressor based on the present invention. This rotary compressor includes a cylindrical casing 1 defining a cylindrical cylinder chamber inside, a front plate 2 attached to the front end of the casing 1, and the casing 1.
It has a rear plate 3 attached to the rear end, and a rear casing 4 attached to the rear end of the rear plate, and the casing 1 and the rear casing 4 have mounting holes 1a for mounting bolts, 4a are provided respectively. A rotor 5 is rotatably and eccentrically received within the casing 1 . That is, the rotor shaft 6 of the rotor 5 is rotatably supported by roller bearings 7.8 provided in the front plate 2 and rear plate 3, respectively.

A flange 9 is screwed onto the front end of the rotor @6, and an annular clutch member 11 is attached to the outer periphery of the flange via a leaf spring member 10. On the other hand, a boolide 3 is rotatably attached to the outer circumference of the front plate 2 via a ball bearing 12, and the front surface of the boolide faces the clutch member 11 with a small gap therebetween.

The pulley 13 has an annular recess 13a over the entire circumference of its rear surface.
is recessed, and the electromagnet 14 is fixed to the front plate 2 so as to be located within the recess. This electromagnet 14 is selectively excited by a current supplied from its lead wire 14a, and the clutch member 11 is attached to the front surface of the pulley 13.
The clutch device constitutes a clutch device that selectively engages the pulley 13 and the rotor shaft 6 to connect and disconnect the power transmission between the pulley 13 and the rotor shaft 6.

A mechanical seal structure is provided on the outer periphery of the rotor shaft 6 between the 7 flange 9 and the bearing 7 to prevent lubricating oil for lubricating the bearing 7 from leaking to the outside. This mechanical seal consists of a fixed member 15 fixed to the front plate side, and a rotating part 16 that rotates integrally with the rotor shaft 6 and is biased by a coil spring 17 and slides into liquid-tight contact with the fixed part 15. It has become.

As clearly shown in FIG. 2, vane grooves 18 consisting of three axial grooves are cut at equal intervals in the circumferential direction on the outer periphery of the rotor 5. A member 19 is fitted. These vane members 19 connect the cylinder chamber inside the casing 1 to the suction chamber a.
It is divided into a compression chamber (1) and a discharge chamber (C), and the volume of these chambers increases and decreases with rotation from 0 to 5, thereby pressurizing a working fluid such as a refrigerant.

The fluid to be compressed is introduced from the suction port 20, passes through the filter 21 and the suction path 22, and is introduced into the suction chamber a from the recess 23 formed in the inner peripheral surface of the housing 1. The fluid is further pressurized within the compression chamber, and is discharged from a recess 24 formed in the inner circumferential surface of the housing 1 to a discharge passage 25 via a discharge chamber C. A reed valve 27 is provided between the discharge passage 25 and the discharge chamber 29, and its maximum opening is regulated by a valve holder 26 screwed with a bolt 28.

The pressurized fluid discharged toward the discharge chamber 29 flows through the discharge passage 30
The lubricating oil is introduced into the high pressure chamber 31 defined in the rear casing 4, and the lubricating oil mixed therein is separated by an oil separator (not shown), and then passed through the discharge passage 32 to the discharge port 3.
It will be discharged from 3. The lubricating oil separated by the oil separator is collected in the oil [34] at the bottom of the high pressure chamber 31.

An annular depression 36 is formed in the lower part of the rear surface of the rear plate 3, which is located below the ffl oil level 35 when the oil reservoir 34 is stopped, and an annular protrusion 38 is defined in the center thereof. There is. An oil return passage 39 is defined in the center of the annular protrusion 38 .

A valve retainer 37 is fitted into the opening of the annular recess 36 facing the oil M34 side, and as clearly shown in FIGS. 3 and 4, a filter 40 is installed inside the valve retainer 37. is attached, and the valve body 41 is held in a biased state toward the rear casing by a compression coil spring 42. A notch 41a is provided on the outer periphery of the valve body 41, and the oil reservoir 34 and the annular recess 36 are always communicated with each other regardless of whether the valve body 41 is opened or opened. The filter 40, the valve body 41, the compression coil spring 42, and the valve retainer 37 constitute a 1 m long subassembly, and are fitted into the opening of the annular recess 36 by light press fitting.

In this embodiment, three lubricating oil passages 43 are provided in parallel to each other along the axial direction at positions offset from each other in the bottom of the casing 1 and close to the suction chamber a. These lubricating oil passages 43 are gathered at the front and rear ends of the casing 1 so as to communicate with each other by arc-shaped yts 43b and 43a. The groove 43a communicates with the annular recess 36, and the other groove 43b communicates with the fixed part 15 of the mechanical seal via an oil jet 44 and a lubricating oil passage 45.
It is supplied to the sliding contact portion of the mechanical seal in order to cool the sealing surface between the rotating part 16 and the rotor shaft 6, and also to lubricate the bearing 7 of the rotor shaft 6.

Furthermore, an arc-shaped II recessed in the m oil passage 47 and the front end surface of the rotor! 5a, and is introduced into the vane groove 18 that receives the vane member 19, and applies back pressure to each vane member 19 to urge the vane 19 in the projecting direction. Furthermore, lubricating oil is supplied to the rear end of the rotor shaft 6 from a lubricating oil passage 48 provided in the rear end plate 3 via a vane groove 18 and an arcuate groove 5b provided on the back surface of the rotor 5 similar to that described above. The oil is supplied to the bearing 8 to lubricate it.

The lubricating oil that lubricates and cools these parts is finally discharged into the suction chamber a, which has a particularly low pressure, through the gap between the vane member 19 and the vane groove 18 or the gap between the sliding surfaces at the front and rear ends of the 0-taper 5. The gas is mixed with the pressurized gas and discharged together with the discharged gas into the high pressure chamber 31, and is returned to the oil reservoir 35 by the oil separator as described above.

An oil return passage 39 provided at the center of the annular protrusion 38 opens at the bottom of the compression zb, and the open end of the oil return passage 39 on the high pressure chamber side, that is, the rear end of the annular protrusion 3B, has a slight gap. It faces the valve body 41 at a distance. This is because lubricating oil accumulates in the compression chamber when the rotary compressor stops operating, and when the rotary compressor is started again, there may be a lack of lubricating oil in various parts, or the compressor may become incompressible. This is to avoid damage to the vane members etc. when trying to compress the lubricating oil.

That is, during operation of the compressor, since the pressure in the high pressure chamber 31 is higher than the internal pressure of the compression 'Ib, the valve body 41 is pressed against the open end of the annular protrusion 38 against the spring force of the compression coil spring 32. However, when the operation of the rotary compressor is stopped, the pressure in the high pressure chamber 31 gradually decreases, and the valve body 41 eventually closes the annular protrusion 3 due to the restoring force of the compression coil spring 42.
It separates from the open end of 8. Is there a compression room there? The lubricating oil remaining in the oil reservoir 3 is transported from the oil return passage 39 to the oil sump 3 mainly due to gravity.
4, making it possible to avoid the situation where an attempt is made to pressurize an incompressible fluid as described above.

A valve unit 51 is provided at the center of the back surface of the rear end plate 3 to protrude into the high pressure chamber 31 for promoting the supply of lubricating oil to the vane groove 18 when starting the compressor. This valve unit 51 has a cylindrical casing 52 screwed onto the rear end plate 3 so as to be coaxial with the rotor 5, and a piston 55 slidably received in an inner hole of the casing. The piston 55
The front end of the piston 55 has an enlarged diameter head 55a, which abuts against the shoulder of the casing 52 to prevent the piston 55 from being pulled out rearward. Further, a spring retainer 54 is fixed to the rear end of the piston 55 by a snap ring, and a compression coil spring 53 installed between the spring retainer 54 and a step on the outer periphery of the casing 52 keeps the piston 55 rearward. It is energized towards.

A passage 57 is formed in the intermediate portion of the piston 55 and includes a portion extending in the diametrical direction and a portion extending from the portion toward the front end of the piston 55 and opening toward the cavity 58. This cavity 58 defined at the front end of the piston 55 communicates with the bearing 8, which in turn communicates with the vane groove 18 via the lubricating oil passage 48 and the arcuate groove 5b of the rotor 5. A plurality of labyrinth grooves 56 are provided around the outer periphery of the piston 55 rearward of the passage 57 to enhance the sealing effect.

When the piston 55 is in the rear position shown in the figure due to the biasing force of the compression square coil spring 53, the lubricating oil in the oil reservoir 34 flows into the annular recess 36 provided in the rear end plate 3.
and the piston 5 through the lubricating oil passage 49, the lubricating oil passage 50 provided in a part of the casing 52, and the throttle passage 50a.
The oil is supplied to a lubricating oil passage 57 bored inside the lubricating oil passage 5 . However, when the piston 55 is displaced to the forward position, the communication between the throttle portion 50a and the lubricating oil passage 57 of the piston 55 is cut off, and the oil sump 34 is transferred to the piston 55.
The lubricating oil cannot be supplied to the lubricating oil passage 57 of No. 5.

In the second ill yarn system described above, when starting the compressor, lubricating oil is supplied to the vane groove 18 through the cooling lubricating oil passage 43,
If only the lubricant is supplied from the first lubricant passage including the lubricant passage 45 and the mechanical seal, the supply of back pressure to the vane member 19 at the time of starting the compressor will be insufficient, and the noise caused by chattering by the vane member 19 will be interrupted. It was established in consideration of the current situation. By providing the second lubricating oil passage having the valve unit 51, when the pressure in the high pressure chamber 31 rises to such an extent as the compressor starts, the lubricating oil in the oil sump 34 flows into the lubricating oil passage 49. The oil is supplied to the vane groove 18 relatively quickly through the second lubricating oil passage 50 and the throttle portion 50a, which leads to the lubricating oil passage 57 of the piston 55, the cavity 58, and the bearing 8, where there are relatively few obstacles. It will be done.

When the pressure in the high pressure chamber 31 further increases, the piston 55 moves forward due to the pressure balance between the empty chamber 58 and the high pressure chamber 31, and the supply of lubricating oil to the RAW4 oil passage 57 inside the piston 55 is stopped. Back pressure is supplied to 18 only by lubricating oil supplied from the first lubricating oil passage on the side of the mechanical seal.

As explained above, according to the present invention, even when the operation of the compressor is stopped for a long time, the valve body 41 opens as the residual pressure in the high pressure chamber 31 decreases, and the am Since the oil is collected from the oil return passage 37 into the oil sump, the lubricating oil inside the compressor is absorbed into the intermediate compression chamber. When the compressor is restarted without one station being filled, there will be no shortage of lubricating oil or compressing the lubricating oil, and as the pressure in the high pressure chamber 31 increases slightly, the valve body 41 will close. It closes automatically and does not cause any trouble during normal operation of the compressor.

As described above, according to the present invention, with an extremely simple structure, lubricating oil can be recovered when the compressor is stopped, and the inconvenience caused by excessive lubricating oil remaining in the intermediate compression chamber can be avoided. can be avoided. Moreover, since this is configured as part of the lubricating oil path, the structure is compact and simple, which has the great effect of improving the reliability and performance of the compressor without increasing its manufacturing cost or increasing the size of the device. can be played.

[Brief explanation of the drawing]

FIG. 1 is a vertical view of a rotary compressor according to the invention. FIG. 2 is a sectional view taken along line II--II in FIG. 1. FIG. 3 is an enlarged longitudinal cross-section showing the main part of FIG. 1 in detail. 1... Casing 1a... Mounting hole 2... Front end plate 3... Rear end plate 4... Rear casing 4a... Mounting hole 5... Rotor 5a, 5b... Arc-shaped groove 6 ...Rotor shaft 7.8...Bearing 9...7 Lunge
10... Leaf spring member 11... Clutch member" 12
... Ball bearing 13 ... Pulley 13a ... Annular groove 14 ... Electromagnet 15 ... Fixed part 16
...Rotating part 17...Compression] Illu spring 18.
... Vane groove 19 ... Vane member 20 ... Suction port 21 ... Filter 22 ... Suction path
23.24... Depression 25... Discharge passage 2
6... Single presser 27... Reed valve 28... Screw 29... Discharge chamber 30... Discharge passage 31.
...High pressure chamber 32...Discharge path 33...Discharge port 34...Oil reservoir 35...Lubricating oil level 36
...Annular recess 37...Valve retainer 38...Annular protrusion 39...Return passage 40...Filter 4
1... Valve body 41a... Notch portion 42...
Compression coil spring 43...cooling lubricating oil passages 43a, 43
b...Groove 44...Jet 45...Lubricating oil path
47-50... Lubricating oil path 50a... Squeezing oil path
51... Valve unit 52... Casing
53... Compression coil spring 54... Spring retainer 5
5... Piston 55a... Expanded diameter head 56...
Labyrinth groove 57...Lubricant oil path 58...Vacant patent Applicant: Honda Motor Co., Ltd.
Attorney Patent Attorney Yo Oshima
-2IE2v! !

Claims (1)

[Scope of Claims] A cylindrical cylinder chamber, a rotor having a vane groove on the outer periphery, a vane member received in the vane groove so as to be freely protrusive and retractable, and an oil reservoir provided on the discharge side to the bottom of the vane groove. In the vane rotary compressor, the oil return passage communicating between the bottom of the cylinder chamber and the oil sump is concentric with the opening end of the lubrication oil path on the oil sump side. A vane type rotary compressor, characterized in that the oil return passage is provided with a closing valve that opens only when the discharge pressure of the compressor is low.