JPS63129184A - Gas compressor - Google Patents

Abstract

PURPOSE:To prevent the vane chattering phenomenon by cutting off the communication of the bottom part of a vane in the range where the top edge of the vane obtains a superhigh pressure, to a small hole for feeding the high pressure oil and the groove part for feeding the intermediate pressure oil. CONSTITUTION:Each shape of a small hole 21 for feeding the high pressure oil and the groove parts 19 and 24 formed on a rear side block 3 and a control plate 22 are specified. In the range where a vane 4 reaches the short diameter part of a cylinder chamber from a discharge port 1b, the bottom part of the vane 4 does not communicate to the small hole 21 nor to the groove part 19 at all. Therefore, the high pressure oil can be perfectly confined in the bottom part space of the vane, and the vane chattering can be prevented.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a rotary vane type gas compressor used in car coolers and other relatively small-sized refrigeration equipment.
In particular, the present invention relates to a gas compressor suitable for preventing chattering in a variable capacity gas compressor.

(Prior art) In general, rotary vane type gas compressors are
As shown in the figure, vanes 4 and 4 that can move forward and backward in the radial direction are installed in a cylinder chamber that is composed of a cylinder 1 that has a substantially elliptical inner circumference, and front and rear side blocks 2 and 3 that are attached to both sides of the cylinder 10. A compressor main body 6 is formed by rotatably horizontally suspending a rotor 5, and a space 7 is formed at the rear of the rear side block 3 to house the compressor main body 6. A casing 9 having one end open is provided for storing lubricating oil 8 under the discharge pressure of the gas discharged from the discharge port of the cylinder chamber.

The gas that enters the cylinder chamber from the intake port 11 of the front head 10 through the intake port 1a of the cylinder 1 is compressed at each working position as the vanes 4 advance and retreat as the rotor 5 rotates, and becomes a high-pressure gas. The oil enters the space 7 through the discharge port 1b and the oil separator 12, and is supplied to the outside through the discharge port 13 of the casing 9.

In the rotary vane type gas compressor as described above, the lubricating oil 8 is transferred to the oil distribution path formed in the rear and front side blocks 2 and 3 and the cylinder 1 by the discharge pressure of the gas from the cylinder chamber. 14, 15.16
The lubricant is supplied to the bearing portion of the rotor shaft 5a through the lubricant, and performs a lubricating action. Further, some of the lubricating oil is depressurized in the gap between the front and rear rotor bearings, and is supplied to a slit (not shown) formed in the rotor 5 through communication holes 17 and 18, and is supplied to the back of the vane 4. It is used as pressure. The synergistic effect of this oil pressure and the centrifugal force accompanying the rotation of the rotor 5 causes the vanes to come into contact with the cylinder interior wall, and each vane is pushed up by the same pressure. ing.

However, even after the rotor 5 rotates and discharges compressed gas from the discharge port 1b, the cylinder 1. There is a space separated by the rotor 5 and the vanes 4, so if, for example, oil mist or liquefied refrigerant is mixed in the gas in this space, high pressure will be generated to compress the liquid. Therefore, the vane 4 instantaneously sinks into the rotor 5 against the back pressure of the lubricating oil, and then projects to the inner wall surface of the cylinder 1.

At this time of re-extrusion, a collision sound with the cylinder inner wall surface is generated, causing chattering.

Previously, the applicant proposed a gas compressor that was devised to apply back pressure in accordance with the amount of protrusion of the vanes, and also to apply high back pressure in areas where high pressure is temporarily applied near the discharge port. An application has been filed (see Utility Model Application Publication No. 104381/1981).

As shown in FIG.
, 3, a pair of grooves 19 and 20 are formed on the end surface in contact with the rotor 5, and the grooves 19 and 20 expand in a fan shape at 180° symmetrical positions around the bearing.
A pair of small holes 21 communicating with the high-pressure oil flow paths 14 and 16 are opened at positions facing the 14 and 16, and are made to face the bottom of the vane 4 passing through the small holes 21.

According to this configuration, the fan-shaped grooves 19 and 20 can apply back pressure with a pressure distribution according to the protrusion amount distribution of the vanes, and high-pressure lubricating oil can be applied through the small holes 21 in areas where chattering occurs. Since it acts on the back surface of the vane, it counteracts the force pushing down the vane, and as a result, no chattering phenomenon occurs.

However, in a structure that uses the discharge pressure of lubricating oil to adjust the back pressure of the vane 4, it is difficult to adjust the back pressure.
In capacity-controlled gas compressors, which are now widely used, a control plate is interposed between the rotor and the front side block, which creates a large gap, making it difficult to apply appropriate hydraulic pressure to the bottom of the vane. Therefore, the actual situation is that with the structure described above, the initial effect cannot necessarily be obtained in a variable capacity type gas compressor or the like.

(Problems to be Solved by the Invention) This invention has been made in view of the above-mentioned circumstances, and the problem to be solved by the present invention is to reliably prevent the vane chattering phenomenon of a gas compressor. In particular,
The purpose is to prevent chattering in variable capacity gas compressors where it is difficult to adjust the back pressure of the vanes.

(Means for Solving the Problems) In order to solve the above problems, the present invention comprises a cylinder whose inner circumference is approximately elliptical, and both side blocks attached to both sides of the cylinder. A compressor body is formed by horizontally suspending a rotor having a plurality of vanes that can move forward and backward in the radial direction in a cylinder chamber, and a space is formed at the rear of a rear side block in this compressor body. It is equipped with a sealed casing that stores lubricating oil under discharge pressure and rotatably holds the tip of the rotor shaft of the rotor. On the rotor side contact surface,
A small hole to which high-pressure lubricating oil is supplied and a groove to which medium-pressure lubricating oil is supplied are provided, and the bottom of the vane and these small holes,
In a gas compressor in which the contact pressure of the vanes against the inner wall of the cylinder chamber is obtained by communicating grooves, the small hole is shifted in a direction opposite to the rotational direction of the rotor from the position of the discharge port in the cylinder chamber. position, while the ends of the grooves are set at positions offset from the short diameter part of the cylinder in the rotational direction of the rotor.
In the section from when the tip of the vane passes through the discharge port to the short diameter section, the bottom of the vane is out of communication with the small hole and groove, and high-pressure oil is trapped in the bottom of the vane in this section. It is characterized by the following.

(Function) According to the above configuration, in the section where the tip of the vane is under ultra-high pressure (from immediately after the discharge port to the short diameter portion of the cylinder), the bottom of the vane is connected to the small hole that supplies high-pressure oil and the groove that supplies medium-pressure oil. Both are in a non-communicating state, and even if ultra-high pressure is applied to the vane tip, the high-pressure oil trapped in the bottom space of the vane has nowhere to escape, so this oil pressure and the high pressure applied to the vane tip compete with each other. The vane tip does not separate from the inner surface of the cylinder, and vane chattering can be reliably prevented.

(Description of Embodiment) Hereinafter, one embodiment of the present invention will be described in detail using the drawings.

However, in this embodiment, the same reference numerals will be used for parts that are the same as in the prior art, and only new parts will be explained using different reference numerals.

FIG. 1 is a side sectional view showing an embodiment in which the present invention is applied to a variable capacity gas compressor, and FIGS. 2 and 3 are plan views showing a rear side block of the same gas compressor.

In Figure 1, front side block 2 and rotor 5
A control plate 22 is installed between the rotor shaft 5a and the rotor shaft 5a, and is rotatably supported by the rotor shaft 5a.

For reference, a bypass recess (not shown) is provided at the periphery of the control plate 22, and when the control plate 22 is rotated by a predetermined angle, the bypass recess connects the front 1-side block 2 (also not shown). By communicating with the bypass hole of the cylinder chamber and bypassing the gas in the cylinder chamber to the suction chamber side, the capacity of the working chamber can be made variable.

In this gas compressor, the rear side block 3, cylinder 1, and front side block 2 are provided with high-pressure communication holes 14, 15, and 16 for communicating lubricating oil 8, as in the conventional case.
are formed respectively, and directly from the communication hole 14,
High-pressure oil is supplied to the small holes 21, and medium-pressure oil obtained by reducing the pressure of these high-pressure oils is supplied to the groove 19 of the rear side block 3 via the communication hole 17, and similarly via the communication hole 18. It is supplied to the groove portion 20 of the front side block 2. In addition, in this embodiment, since the control plate 22 is interposed between the rotor 5 and the front side block 2, this control plate 22 is also provided with communication holes 23 and grooves 24.

Next, the positional relationship between the small hole 21 for supplying high-pressure oil and the groove portion 19.24 for supplying medium-pressure oil will be explained.

First, the small hole 21 is provided at a position slightly shifted from the discharge port 1b in the direction opposite to the rotating direction of the rotor 5, and when the tip of the vane 4 passes through the discharge port 1b, the bottom of the vane 4 and the small hole 21 do not communicate with each other.

Roughly speaking, the surface shape of the groove portions 19 provided in the rear side block 3 is a pair of fan-like openings formed at 180° symmetrical positions around the bearing portion of the rotor shaft 5a.
They are located at the center of the pair of small holes 21, respectively. In addition, the end 19a of the groove 19 is set at a position slightly shifted from the short diameter part of the cylinder chamber in the rotating direction of the rotor 5, so that the bottom of the vane 4 does not reach the groove 1 until the vane 4 passes through the short diameter part.
9, and intermediate pressure is applied to the vane 4.

Note that the surface shape of the groove portion 24 formed in the control plate 22 is shown by broken lines in FIGS. 2 and 3.

As described above, in the gas compressor according to the present invention, the setting position of the small hole 21 for supplying high-pressure oil and the shape of the groove portions 19 and 24 provided in the rear side block 3 and the control plate 22 are modified, and as shown in FIG. As shown in FIG. 3, in the section from when the vane 4 is immediately behind the discharge port 1b until the vane 4 reaches the short diameter part of the cylinder chamber as shown in FIG. Since the bottom of the vane 4 does not communicate in this section, the bottom of the vane 4 is completely enclosed in this section.

Therefore, in this section where the chaketering phenomenon occurs, high-pressure oil is trapped at the bottom of the vane, so even if ultra-high pressure is applied to the tip of the vane 4, the same oil pressure will be generated in the space at the bottom of the vane 4. The tip of the vane 4 does not separate from the inner wall surface of the cylinder, and the vane chattering phenomenon can be reliably prevented.

Although the above-described embodiment is applied to a variable capacity gas compressor using the control plate 22, it does not depart from the scope of the present invention even if it is applied to a normal gas compressor.

(Effects of the Invention) As described above in detail in the embodiments, in the gas compression technique according to the present invention, by having the above-described configuration, back pressure is applied according to the amount of protrusion of the vane, and
Corresponding to the area where pressure is particularly applied, that is, the area where high pressure is temporarily applied near the discharge port, the bottom of the vane is made non-communicating with the high pressure supply hole in this area, completely closing the high pressure oil in the space at the bottom of the vane. Since the vane is made smaller, it is possible to reliably prevent chattering in the vicinity of the discharge port even in a capacity control type gas compressor or the like in which hydraulic pressure is not easily applied to the bottom of the vane. With the above configuration, the contact pressure of the vane against the inner wall surface of the cylinder can be controlled to a desired value, which eliminates uneven contact friction between the two, improving wear resistance and, in addition, placing a large load on the prime mover side. It has various effects such as being able to drive without any friction.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing a gas compressor according to the present invention, and FIG.
3 to 3 are plan views of the rear side block of the same gas compressor, FIG. 4 is a side sectional view of the conventional gas compressor, and FIG. 5 is a plan view showing the conventional rear side block. 1...Cylinder 2...Front side block 3...Rear side block 4...Vane 5...Rotor 6...Compressor body 8...Lubricating oil 14.15.16...Oil Distribution route 17, 18...Communication hole 19, 20, 24...Groove 21...High pressure supply hole 22...Control plate and above Patent applicant: Seiko Seiki Co., Ltd. Original"ry-frJ diagram No. 5
figure

Claims (1)

[Claims] (1) A rotor that has a plurality of vanes that can move forward and backward in the radial direction inside the cylinder chamber, which is composed of a cylinder whose inner circumference is approximately elliptical and both side blocks attached to both sides of the cylinder, can be freely rotated. A space is formed at the rear of a horizontally mounted compressor body and a rear side block of the compressor body, and lubricating oil under discharge pressure is stored in this space, and the tip of the rotor shaft of the rotor is rotated. It is equipped with a sealed casing that can be held freely, and the lubricating oil is supplied to each part of the compressor body by discharge pressure.The rotor-side contact surfaces of both side blocks have small holes through which high-pressure lubricating oil is supplied, and A groove portion is provided to which pressure lubricating oil is supplied,
In a gas compressor in which the contact pressure of the vane against the inner wall of the cylinder chamber is obtained by communicating the bottom of the vane with these small holes and grooves, the small hole is located closer to the rotor than the discharge port position in the cylinder chamber. The ends of the grooves are set at positions offset in the direction opposite to the rotational direction of the cylinder, and the ends of the grooves are set at positions offset from the short diameter portion of the cylinder in the rotational direction of the rotor.
In the section from when the tip of the vane passes through the discharge port to the short diameter section, the bottom of the vane is out of communication with the small hole and groove, and high-pressure oil is trapped in the bottom of the vane in this section. A gas compressor characterized by: