JPH0456156B2 - - Google Patents

Description

[Detailed Description of the Invention] <<Industrial Application Field>> The present invention relates to a rotary vane type gas compressor used in car coolers and other relatively small-sized refrigeration equipment, and in particular, the invention relates to a rotary vane type gas compressor used in car coolers and other relatively small-sized refrigeration equipment. The present invention relates to a gas compressor that reduces power consumption and improves vane durability by canceling a prevention mechanism.

<Prior Art> Generally, as shown in FIGS. 5 and 6, a rotary vane type gas compressor includes a cylinder 1 having a substantially elliptical inner circumference, and front and rear side blocks 2 attached to both sides of the cylinder 1. 3;
In addition to accommodating the rear side block 3
A space 7 is formed at the rear of the cylinder chamber, and the space 7 is provided with a casing 9 having one end open for storing lubricating oil 8 under the 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 into high-pressure gas at each working position by the forward and backward movement of each vane 4 as the rotor 5 rotates. , enters the space 7 through the discharge port 1b and the oil separator 12, and enters the casing 9.
It is designed to be supplied to the outside from the discharge port 13 of the.

In the rotary vane type gas compressor as described above, the lubricating oil 8 is transferred to the oil 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. The rotor shaft 5a through the distribution channels 14, 15, 16
It is supplied to the bearings, etc., and performs a lubricating action.

Further, some of the lubricating oil is depressurized by the gap between the front and rear axes, is supplied to a not-shown slit formed in the rotor 5 via communication holes 17 and 18, and is used as back pressure for the vane 4. has been done.

The synergistic effect of this oil pressure and the centrifugal force accompanying the rotation of the rotor 5 allows the vanes to come into contact with the cylinder interior wall, and each vane is pushed up by the same pressure. It's becoming like that.

However, even after the rotor 5 rotates and discharges compressed gas from the discharge port 1b, there is a space partitioned by the cylinder 1, the rotor 5, and the vane 4, so the gas in this space contains, for example, oil. When mist or liquefied refrigerant is mixed in, high pressure is generated to compress the liquid, and this causes the vanes 4 to instantly move into the rotor 5 against the back pressure of the lubricating oil. Immerse yourself in
Next, an action of protruding onto the inner wall surface of the cylinder 1 is performed.

At this time, when the protrusion occurs, 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. 104381/1983).

As shown in FIG. 5, on the outer periphery of the bearing portions of both side blocks 2 and 3, a pair of fan-like openings are provided on the end surfaces in contact with the rotor 5 at positions 180 degrees symmetrical about the bearing portions. Wires 19 and 20 are bored, and a pair of small holes 21 communicating with the high-pressure oil flow path 14 are formed at a position facing the discharge port 1b, and the bottom of the vane 4 passing through these holes faces the bottom. It is something that

According to this configuration, 19,20
This makes it possible to apply appropriate back pressure according to the distribution of the protrusion amount of the vane, and in areas where chattering occurs, high-pressure lubricating oil acts on the back surface of the vane through the small holes 21, creating a force that pushes the vane down. As a result, no chattering phenomenon occurs.

However, although this configuration is very effective in preventing chattering during low-speed operation of the gas compressor, during high-speed operation, the centrifugal force applied to the vanes increases, so the vane sliding torque increases. As power consumption increases,
It has been pointed out that the vane tips are subject to severe wear, which significantly reduces the durability of the vanes.

<Problems to be Solved by the Invention> This invention has been made in view of the above-mentioned circumstances.The problems to be solved by the present invention are to provide an effective chattering prevention mechanism during low-speed operation of a gas compressor. The objective is to cancel this during high-speed operation, thereby reducing power consumption and improving the durability of the vane.

<Means for Solving the Problems> In order to solve the above problems, the present invention includes 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 the rear side block of the compressor body. A sealed casing stores lubricating oil under discharge pressure and rotatably holds the tip of the rotor shaft of the rotor, and supplies the lubricating oil to each part of the compressor body by the discharge pressure, and Front and rear wipers and small holes are provided on the rotor side end face of the block, and the wipers and small holes are communicated with medium-pressure and high-pressure communication paths for lubricating oil, respectively, and normally a constant hydraulic pressure is applied to the vane from the wiper. In addition, in the gas compressor, high-pressure hydraulic pressure is applied only to a certain angular range of the rotor through the small hole to obtain the contact pressure of the vanes against the inner wall of the cylinder chamber. A control plate is supported on the rotor shaft and is rotatably driven according to the operating speed of the compressor during
A front wiper is provided on the bearing part of this plate, and during high-speed operation, the control plate rotates, the front wiper position moves, and high-pressure lubricating oil is supplied to the bottom of the vane within a certain angle range of the rotor. By letting it escape to the front side,
It is characterized by reducing hydraulic pressure.

<<Operation>> According to the above configuration, during low-speed operation of the gas compressor, in the section where the tip of the vane is under ultra-high pressure (from immediately after the discharge port to the short diameter part of the cylinder), the bottom of the vane is either supplied with high pressure oil or Because the high-pressure oil is trapped, the vane tips do not separate from the cylinder inner wall, and vane chattering can be reliably prevented.

During high-speed operation of the gas compressor, the control plate is rotated and the position of the wiper formed on the plate moves accordingly, causing the high-pressure oil supplied to the bottom of the vane to try to escape to this wiper side. During high-speed operation, reduced medium pressure oil is always supplied to the bottom of the vane at all angular positions, reducing the sliding torque of the vane and improving the wear resistance of the vane tip.

<<Example>> Hereinafter, an example of the present invention will be described in detail using the drawings.

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

FIG. 1 is a side sectional view showing an embodiment in which the present invention is applied to a variable capacity gas compressor, FIG.
The figures are cross-sectional views showing the gas compressor during low-speed operation and high-speed operation, respectively, and FIG. 4 is a configuration diagram of a drive mechanism for a control plate used in the gas compressor.

In FIG. 1, a control plate 22 is installed between the front side block 2 and the rotor 5, and is fitted onto the rotor shaft 5a and rotatably supported.

Bypass recesses 23 are provided on the periphery of the control plate 22, facing each other 180 degrees, and are also provided on the bearing portion of the rotor shaft 5a.
A fan-shaped front side wiper 24 is formed 180 degrees opposite to each other.

In this gas compressor, the rear side block 3, the cylinder 1, and the front side block 2 are respectively formed with high-pressure communication holes 14, 15, and 16 for communicating the lubricating oil 8, as in the conventional case. High-pressure oil is directly supplied to the small holes 21 from the small holes 21, and medium-pressure oil obtained by reducing the pressure of these high-pressure oils is supplied to the rear side block 3 via the communication hole 17.
and a front wiper 24 formed in the control plate 22.

Next, the positional relationship between the small hole 21 for supplying high pressure oil and the washers 19 and 24 for supplying medium pressure oil will be explained.

The small hole 21 is provided at a position slightly shifted from the discharge port 1b in the direction opposite to the rotational direction of the rotor 5, and immediately after the tip of the vane 4 passes through the discharge port 1b, the bottom of the vane 4 It is designed so that it does not communicate with the small hole 21.

Furthermore, the surface shape of the rear side wiper 19 provided on the rear side block 3 is a pair of fan-like shapes that are formed at 180 degrees symmetrical positions around the bearing part of the rotor shaft 5a, and have a top, a pair of small They are located at the center of the hole 21, respectively.

In addition, the end of this rear side wiper 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 rear until the vane 4 passes through the short diameter part. side sweep 19
The vane 4 is in communication with the vane 4, so that intermediate pressure is applied to the vane 4 (see Figures 2 and 3).

Next, the surface shape of the front side wiper 24 formed on the control plate 22 is as shown by the solid line in FIGS. 2 and 3. It is expanded into a fan shape.

Next, during low speed operation of the gas compressor according to the present invention,
The operation during high-speed operation will be explained.

That is, FIG. 2 shows the gas compressor of the present application during low-speed operation, and shows the surfaces of the front side wiper 24 of the control plate shown by the solid line in FIG. 2 and the rear side wiper 19 of the rear side block 3 shown by the broken line in the figure. The shapes almost correspond to each other, and when the bottom of the vane 4 passes through this section, medium-pressure oil is supplied to the bottom of the vane 4, and also passes through the small hole 21 and drains 19, 2.
4, that is, after the vane 4 passes the discharge port 1b until it reaches the short diameter part of the cylinder chamber, high-pressure oil is taken into the bottom of the vane 4, so that the tip of the vane 4 Even if an extremely high pressure is applied, the tip of the vane will not separate from the inner wall surface of the cylinder, and the vane chattering phenomenon can be reliably prevented.

Next, during high-speed operation of the gas compressor of the present invention, the drive mechanism of the control plate 22, which will be described later, operates, and the control plate 22 rotates in the direction of the arrow, and the position of the front wiper 24 formed on the control plate 22 changes accordingly. Since the bottom of the vane 4 is in the position shown in FIG.
or the front side wiper 24, medium-pressure oil is always applied to the bottom of the vane 4, and high-pressure oil is not trapped at the bottom of the vane 4.

In other words, when the gas compressor is operating at high speed, the centrifugal force of the vanes 4 increases significantly due to the high speed rotation of the rotor 5, so the hydraulic pressure at the bottom of the vanes 4 is reduced in this application. ing.

Therefore, excessive sliding torque is not applied to the tip of the vane 4, and wear on the tip of the vane 4 can be suppressed as much as possible, reducing power consumption and extending the life of the vane 4. .

In this embodiment, as a chattering prevention mechanism, high-pressure oil is trapped in the bottom of the vane 4 in the section where ultra-high pressure is applied to the tip of the vane 4. By shifting, the bottom of the vane 4 and the small hole 21 may be communicated in a section where ultra-high pressure is applied to the tip of the vane 4 to supply high-pressure oil to the bottom of the vane 4.

Furthermore, the control plate 22 is provided with a bypass recess 23 as described above, and during low-speed operation shown in FIG. However, during high-speed operation, the control plate 22 rotates in the direction of the arrow in the figure, and the bypass recess 23 also moves, allowing the refrigerant in the cylinder chamber to flow through the bypass hole (not shown) formed in the front side block 2. Since the gas is bypassed to the suction chamber side, the capacity of the compression work chamber is kept very small, especially during high-speed operation.In this way, the capacity of the compression work chamber is made variable according to the operating conditions to prevent overcooling. In this embodiment, the control plate 22 is designed to reduce power consumption.
The plate serves both as a plate for adjusting the back pressure of the vane 4 and a plate for controlling the capacity, but it may also be used only for adjusting the back pressure of the vane 4.

Next, for reference, the drive mechanism of the control plate 22 will be briefly explained based on FIG. 4.

That is, the cylinder 25 is connected to the front head 1
The cylinder 25 is disposed so as to be movable forward and backward in a direction orthogonal to the axis of the compressor, with its tip 25a facing into the suction chamber, and its rear end 25b faces outside.

A spring 26 is inserted into the cylinder 25, and the spring 26 has an appropriate spring pressure so as to always urge the cylinder 25 toward the suction chamber.

On the other hand, a drive pin 27 is placed on the surface of the control plate 22.
The drive pin 27 passes through a cam groove 28 formed in an arcuate shape in the front side block 2, and its tip 27a faces the suction chamber side.

The tip 27a of the drive pin 27 is fitted into an engaging portion 29 provided at the tip 25a of the cylinder 25.

Therefore, the cylinder 25 moves forward and backward due to the differential pressure between the spring pressure of the spring 26 and the suction pressure in the suction chamber.

With this forward and backward movement, the drive pin 27 fitted into the engaging portion 29 rotates around the axis of the control plate 22, thereby rotating the control plate 22 by a required angle.

<<Effects>> As described above in detail with reference to the embodiments, the gas compressor according to the present invention is configured as described above, so that during low-speed operation of the gas compressor,
By supplying high-pressure oil to the bottom of the vane or trapping the high-pressure oil in the part where ultra-high pressure is applied to the tip of the vane, it is possible to reliably prevent the chattering phenomenon near the discharge port, and
During high-speed operation of the gas compressor, the control plate is rotated so that the bottom of the vane is always in communication with either the front side or the rear wiper no matter what rotation angle of the rotor, and medium-pressure oil is always applied to the bottom of the vane. This cancels the vane chattering prevention mechanism that supplies or confines high-pressure oil to the bottom of the vane, so it suppresses the sliding torque of the vane during high-speed operation of the gas compressor. As a result, the power consumption can be significantly reduced, and wear of the vanes can also be prevented, which has the advantage of extending the product life of the vanes.

Furthermore, the gas compressor according to the present application adjusts the back pressure of the vanes by changing the sweeping positions provided on both end faces of the rotor, and has a simple configuration, and especially the compression work chamber in the cylinder chamber. Since the present invention also serves as capacity control to make the capacity variable, the power consumption of the gas compressor is further reduced, so the present application has high practical value.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing a gas compressor according to the present invention, and FIGS. 2 and 3 are sectional views taken along line A-A in FIG. 1, showing states during low-speed operation and high-speed operation, respectively. , Fig. 4 is a configuration diagram showing the drive mechanism of the control plate used in the gas compressor, Fig. 5 is a side sectional view of the conventional gas compressor, and Fig. 6 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...
Rear side wiper, 21...Small hole, 22...Control plate, 24...Front side wiper.

Claims (1)

[Scope of Claims] 1. A plurality of vanes that can move forward and backward in the radial direction are provided in a cylinder chamber that is constituted by 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, and a space is formed at the rear of a rear side block in this compressor body, lubricating oil under discharge pressure is stored in this space, and the rotor is The compressor is equipped with a sealed casing that rotatably holds the tip of the rotor shaft, and the lubricating oil is supplied to each part of the compressor body by discharge pressure, and front and rear wipers and small holes are provided on the rotor side end surfaces of both side blocks. The wiper and the small hole are connected to medium-pressure and high-pressure communication paths for lubricating oil, respectively, and normally a constant hydraulic pressure is applied to the vane from the wiper, and high-pressure hydraulic pressure is applied from the small hole to a certain angle range of the rotor. In this gas compressor, the contact pressure of the vanes against the inner wall of the cylinder chamber is obtained by applying only pressure to the inner wall of the cylinder chamber. a control plate supported on the rotor shaft, and
A front wiper is provided on the bearing part of this plate, and during high-speed operation, the control plate rotates, the front wiper position moves, and high-pressure lubricating oil is supplied to the bottom of the vane within a certain angle range of the rotor. By letting it escape to the front side,
A gas compressor characterized by reducing hydraulic pressure.