JPH01224491A - Gas compressor - Google Patents

Abstract

PURPOSE:To economize fuel for a gas compressor and improve its cooling efficiency by arranging a control plate driving mechanism as it touches a spring at its one end, is connected to a control plate and comprises a drive shaft and a hydraulic discharge valve. CONSTITUTION:A driving mechanism 30 for a control plate 10 is arranged as it touches a spring 32 at its one end and is connected to the control plate 10. The control pate 10 is rotated in accordance with the movement of a drive shaft 33 in a slot 31. Arranged on the way of a through hole 37 connected to a mechanical seal room 7a of a rotor shaft 7 is a discharge passage 39 which is connected to an intake-side comprising a hydraulic discharge valve which is composed of an electromagnetic valve 38. Thus, a friction torque is reduced, so that fuel for a gas compressor is economized and its cooling efficiency is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a gas compressor, and particularly to a rotary vane type variable capacity gas compressor used in cartaras and other relatively small-sized refrigeration equipment.

(Summary of the Invention) The present invention supplies hydraulic pressure of a control plate drive mechanism, which maintains low pressure when the rotor rotates at high speed and high pressure when the rotor rotates at low speed, to the vane pressure chamber to increase the vane pressure. It is necessary to have it.

(Prior art) A conventional rotary vane type variable capacity gas compressor has a solid cylindrical rotor equipped with a plurality of vanes that can move forward and backward in the radial direction within a cylinder chamber that has an approximately elliptical inner circumference. It is suspended horizontally so that it can rotate freely.

A compression work chamber is formed in a space with a crescent-shaped cross section surrounded by the cylinder inner wall and the solid cylindrical outer peripheral wall, and when the vane moves within this compression work chamber, gas (refrigerant gas) is sucked into the compression work chamber. The previous vane acts to compress the gas sucked in by the subsequent vane.

At this time, vane pressure is applied to the vanes so that they come into contact with the inner wall of the cylinder at a predetermined pressure in order to prevent the jittering phenomenon during compression work, and this pressure uses hydraulic pressure generated by the discharge gas pressure.

By the way, in a variable capacity compressor, a rotatable control plate is placed on the end face of the rotor, and a part of the gas sucked in through this control plate is bypassed, and the gas compressed by the vanes is The capacity is adjustable.

This type of gas compressor is effective when used as a car cooler. In other words, since the gas compressor is rotationally driven via the engine shaft and V-belt, there is a risk of overcooling when the engine speed becomes high. This is because it is possible to prevent overcooling by adjusting the amount of gas compressed when the air conditioner reaches 100%.

(The problem that the invention seeks to solve).

However, in the above-mentioned gas compressor, since the vane pressure is always maintained high by the hydraulic pressure generated by the discharge gas pressure, there is a drawback that the friction torque at the tip of the vane is large and the driving power is large.

In particular, when the amount of compressed gas is adjusted to be small during high-speed operation, the vane pressure is maintained high even when it is not compressed until the vane tip passes through the bypass hole, resulting in a problem of increased friction torque. there were.

Roughly speaking, as the friction torque increases, the amount of frictional heat increases,
This not only increases the temperature of the discharged gas but also causes severe wear on the vanes.

(Means for Solving the Problems) The present invention has been made to solve the above problems, and includes a cylinder block with a substantially elliptical inner cylindrical shape provided between a pair of side blocks, A rotor horizontally suspended rotatably in a cylinder chamber formed by a cylinder block and both side blocks, a vane installed in a vane groove provided in the rotor so as to be freely retractable, and the rotor and the one side block. It has a control plate that is rotatably provided in between, and a control plate drive mechanism for rotationally driving the control plate, and after adjusting the volume of gas taken in from the intake side with the control plate and compressing it in the cylinder chamber. In a rotary vane type gas compressor that discharges gas, the control plate drive mechanism has one end in contact with a spring and is connected to the control plate, and is located on the intake side and is pressed by the pressure on the intake side and the spring pressure. , the other is located in a chamber to which oil pressure of lubricating oil generated by the discharge gas pressure is supplied, is pressed by the oil pressure, and moves and stops at a position where the two pressing forces are maintained in balance; an oil pressure release valve that is provided in a discharge path that communicates with the intake side and moves the drive shaft so as to lower the oil pressure in the chamber and reduce the amount of compressed gas when the rotor rotates at high speed; and a communication path that communicates the vane groove with the vane groove.

(Function) With the above configuration, the hydraulic pressure that drives the control plate decreases as the rotation speed increases, and the control plate is rotated to reduce the number of compressed gas ports, and the vane pressure is generated by the hydraulic pressure. Therefore, the vane pressure decreases as the oil pressure decreases.

(Description of an embodiment) Hereinafter, an embodiment of a gas compressor according to the present invention will be described using the accompanying drawings. The basic configuration of the gas compressor in this embodiment was previously disclosed in Japanese Patent Application No. 1983-300 by the present applicant.
This was proposed by @3.

FIG. 1 is a longitudinal cross-sectional view of a gas compressor main body according to the present invention, FIG. 2 is a cross-sectional view taken along the line ■-■ in FIG. 1, and FIG. 3 is a cross-sectional view taken along the line ■-■ in FIG. The gas compressor main body 1 includes a casing 2 with one end open, and a front head 3 on the open end surface of the casing 2.

Inside the casing 2, there is a cylinder block 4 having a substantially elliptical inner circumference, and a front side block 5 and a rear side block 6 attached to both sides of the cylinder block 4.
In the cylinder chamber a, which has a substantially elliptical inner circumference formed by these side blocks, there are five flat blocks that are integral with the rotor shaft 7 and that are movable in the radial direction of the rotor shaft 7. A solid cylindrical rotor 9 equipped with plate-shaped vanes 8 is horizontally suspended for free rotation.

The vane 8 is attached to the rotor 9 in a vane groove that extends around the rotor 9 in the direction of its rotation axis, has a cross section slightly larger than the cross section of the vane 8, and has a depth slightly deeper than the height of the vane 8. 9a is provided, and the vane 8 is inserted into this vane groove 9a.

A vane pressure chamber 9b is formed at the bottom of the vane groove 9a, and the cross-sectional area is larger than that at the top, and the lubricating oil in the casing 2 is supplied to this vane pressure chamber 9b. .

That is, the lubricating oil O flows through the oil flow paths 6a, 4a, and 5a formed in the rear side block 6, the cylinder block 4, and the front side block 5, the control plate drive mechanism described later, and the control plate drive mechanism that connects the vane groove 9a. The air is supplied to the vane pressure chamber 9b through the communicating path.

[11
17 and is supported.

The peripheral edge of the control plate 10 has a bypass recess 11, I
The bypass recesses 11 are configured to communicate with the suction ports 12 and the bypass holes 5b provided in the front 1 to the side block 5.

That is, this control plate 10 can be rotated within a predetermined angle by a control plate drive mechanism that will be described later. For example, when the rotor 9 is rotating at a low speed, the control plate 10 is rotated to a position where the intake refrigerant gas is not bypassed. ,
The maximum capacity of the compression work chamber in the cylinder chamber a is ensured.

On the other hand, during high-speed operation, the control plate 1
0 rotates clockwise in Fig. 2, bypass recess 1
1 and the bypass hole 5b provided in the side block 5, a part of the refrigerant gas in the compression chamber is bypassed to the suction side through the bypass hole 5b, and as a result, the capacity of the compression chamber is reduced. It is compressed only by the decrease.

Before explaining this control plate drive mechanism, the flow of refrigerant gas in the variable capacity gas compressor configured in this way will be explained.

First, the refrigerant gas is introduced into the suction chamber 15 from the intake port 14 provided in the front head 3, passes through the intake port 12, and passes through an intake passage formed through the cylinder block 4, as shown by arrow A in FIG. 16, and this intake passage 16
It is sucked into the cylinder chamber a through notches 17a and 17b provided at both ends of the cylinder.

Next, the high pressure gas compressed by the rotation of the vane 8 passes through the discharge port 18a, the discharge valve 18b, and the communication hole 6b provided in the rear side block 6 to the rear side block 6.
The oil is supplied to an oil separator 19 provided at the back of the casing 2, reaches the rear space of the casing 2 as shown by the arrow in FIG. 1, and is discharged from there to the outside through a discharge port 20.

Also, since the lubricating oil O in the rear space is compressed high-pressure gas and is maintained at high pressure (15 to 20 kCJ/cm2) I,;:,M, the cylinder block 4. The oil is supplied to the shaft of the rotor 9 through the oil distribution channels 4a, 5a, and 6a formed in the front side block 5 and the rear side block 6 to perform a lubricating action, and as described above, it is supplied into the vane pressure WQb to lubricate the shaft of the rotor 9. Generates pressure.

The drive mechanism 30 of the control plate 10 is shown in FIG. That is, a long hole 31 having two diameters extending from one end of the outer periphery of the freon 1 to the head 3 to the inner wall of the suction chamber 15 opposite to this end is recessed, and a short diameter portion 31a in this long hole 31 is formed.
A drive shaft 33 is hermetically and slidably housed in the drive shaft 33, and a spring 32 is brought into contact with the tip of the drive shaft 33. Further, the tip of the large diameter portion 31b is sealed with a plug 34 to form a chamber 31C.

A recess 34 is formed at the tip of the drive shaft 33 on the spring 32 side, and a pin 35 provided integrally with the control plate 10 passes through the guide hole 36 formed in the front side block 5. It is loosely fitted. Therefore, when the drive EMI 133 moves within the long hole 31,
The control plate 10 is also rotated accordingly.

In the chamber 31C provided on the large diameter portion 31b side of the long hole 31,
An oil flow path 5a that communicates with the oil flow path 4a provided in the cylinder block 4, a communication hole 37 that communicates with the mechanical seal chamber 7a of the rotor shaft 7, and a hydraulic release valve consisting of a solenoid valve 38 interposed in the middle thereof. A discharge passage 39 communicating with the intake side is opened.

A passage 40 provided in the mechanical seal lock 5 is provided, which passage 40 communicates with the groove 22 of the control plate 10. That is, the groove 22 and the passage 40.

Up to 31G between mechanical seal chamber 7a and communication hole 37
A communication path is configured to communicate between the vane groove 9a and the vane groove 9a. For this reason, each vane pressure 19b... provided at the bottom of each vane la, 9a... 9b... and the discharge side are maintained in communication via the oil flow passages 6a, 4a, 5a and the communication passages.

The solenoid valve 38 is controlled by the engine speed and the rotation speed of the rotor 9.

That is, when the rotation speed exceeds a predetermined value (for example, 4000 rpm or more), the solenoid valve 38 is turned on, and when the rod 38a is protruded and the ball 38b is pushed out, the discharge path 39 is opened, and a part of the hydraulic pressure in the chamber 31C is released. It is released to the intake side via the passage 39, and the oil pressure in the chamber 31C decreases only by the release valve.

Therefore, the pressure on the intake side, that is, the pressure in the suction chamber 15 (
1.5 ~2. One pressure, which is the sum of Okq/crn2) and the repulsive force (spring pressure) of the spring 32, is balanced by the other pressure, which is the oil pressure (15 to 20 kg/Cm?) in the chamber 31C, and it stops. The drive shaft 33 that was The control plate 10 is moved toward the chamber 31C by the amount that the pressure in the chamber 31c has decreased, and the control plate 10 is rotated so as to bypass the refrigerant gas.

At this time, the decreased oil pressure in the communication hole 37 and the mechanical seal 7a. Since the vane pressure is applied to the vane pressure chamber 9b via the communication path formed by the passage 40 and the groove 22, the vane pressure becomes low. Therefore, the friction torque can be reduced and the driving power can be reduced, and the generation of frictional heat is also reduced, making it possible to lower the temperature of the discharged gas.

On the other hand, when the rotational speed of the rotor 9 or the engine is low and the solenoid valve 38 is off, the rod 38a moves backward and the ball 38b opens the discharge path 39. As a result, the hydraulic pressure in the chamber 31C is no longer released and its pressure increases, so the control plate 10 moves against the repulsive force of the spring 32 until the pressure on both sides is balanced, and the control plate 10 is moved in the opposite direction from the above-mentioned high speed rotation. Rotate it.

At this time, the high-pressure oil pressure in the chamber 31C is applied to the vane pressure chamber 9b through the communication path, so that the vane pressure increases and the chillering phenomenon is effectively prevented.

(Effects) As described above, in the gas compressor according to the present invention, the vane pressure is obtained by the hydraulic pressure of the control plate drive mechanism, which is maintained low when the rotor rotational speed is high and high when the rotor rotational speed is low. Therefore, friction torque during high-speed rotation can be reduced.

Therefore, since only a small amount of driving power is required, fuel efficiency can be improved, and since the frictional heat is reduced by 1q, the temperature of the discharged gas can be lowered, so that the cooling effect can be improved.

[Brief explanation of the drawing]

The drawings show an embodiment of a gas compressor according to the present invention, in which FIG. 1 is a longitudinal sectional view thereof, and FIG.
-II line sectional view and FIG. 3 are sectional views taken along ■--■ line in FIG. 1... Gas compressor main body 2... Casing 3... Front head 4... Cylinder block 5・・・・・・
... Freon] Heside block 6...
Rear side block 8... Vane 9... Rotor 9a... Vane groove 9b... - Vane pressure 10... Control plate 15... Intake (intake side) 30... Control plate drive mechanism 31G... Chamber 32... Spring 33... Drive shaft 37. ...Communication hole 38...Solenoid valve 39...Discharge path a...Cylinder chamber or above Patent applicant Seiko Seiki Co., Ltd.

Claims (1)

[Claims] 1. A cylinder block with a substantially elliptical inner circumference provided between a pair of side blocks, a rotor horizontally suspended rotatably in a cylinder chamber formed by the cylinder block and both side blocks, and A vane installed in a vane groove so as to be freely retractable, a control plate rotatably provided between the rotor and the one side block, and a control plate drive mechanism for rotationally driving the control plate. In a rotary vane type gas compressor, which adjusts the volume of gas sucked in from the intake side with a control plate, compresses it in a cylinder chamber, and then discharges it, the control plate drive mechanism has one end in contact with a spring, and the control plate drive mechanism has one end in contact with a spring and controls the control plate. The other is connected to the plate and is located on the intake side and is pressed by the intake side pressure and spring pressure, and the other is located in a chamber to which the oil pressure of lubricating oil generated by the discharge gas pressure is supplied and is pressed by the oil pressure. a drive shaft that moves and stops at a position where the two pressing forces are balanced, and a discharge passage that communicates the chamber with the intake side, and that reduces the hydraulic pressure in the chamber when the rotor rotates at high speed. A gas compressor, comprising: a hydraulic release valve that moves the drive shaft so as to reduce the amount of gas to be compressed; and a communication passage that communicates the chamber with the vane groove.