JPH0320556Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> This invention relates to a variable capacity gas compressor used in car coolers, etc., and in particular to a gas compressor that precisely controls the capacity of the compression chamber. Regarding.

[Prior art and its problems] Gas compressors used for air conditioning in passenger cars are usually installed in parallel with the engine, driven by a V-belt from the engine's crankshaft pulley, and driven by an electromagnetic clutch mounted on the compressor side. It is designed to be connected to the drive side.

Therefore, the capacity of this type of gas compressor increases in proportion to the engine rotation speed,
Conversely, when driving at high speeds, the gas compressor is driven at high speeds, which causes the cabin to become overcooled, and power consumption also increases proportionately. There are drawbacks, and this tendency is particularly noticeable in rotary gas compressors.

As a countermeasure to this problem, the applicant has already proposed various so-called variable capacity gas compressors in which the capacity of the refrigerant gas compression chamber is varied depending on the driving speed of the gas compressor.

To briefly explain a typical example, a control plate is provided on the inner surface of the front side block of the compressor, and a recess (intake port) communicating with the communication hole of the front side block is formed in the control plate. By rotating this control plate by a predetermined angle, the intake capacity taken in from the communication hole in the front side block can be varied.

However, in a gas compressor that uses this type of control plate to vary the capacity of the compression work chamber, the rotor is strongly pressed toward the front side.
It has been pointed out that the control plate moves slightly toward the rotating side due to the high-speed rotation of the rotor, making it impossible to precisely control the volume of the compression chamber.

The reason for this is that the lubricating oil supplied to each part of the compressor body is supplied to the front and rear ends of the rotor, and vane pressure is applied from both sides of the rotor, but in reality, the vane pressure is applied to the front end where the control plate is installed. The internal pressure of the side vane pressure chamber decreases due to leakage of lubricating oil from the sliding portion of the control plate, and becomes lower than the internal pressure of the rear vane pressure chamber where the control plate is not provided. As a result, the rotor is pushed toward the front, which is considered to have an adverse effect on the rotation control of the control plate.

In addition, recently, in order to improve compression efficiency, it is necessary to tightly seal the front end surface of the rotor and the control plate, which makes the control plate more susceptible to the pressing force from the rotor. Precise control of the plate was desired.

《Purpose of the invention》 This invention was made in view of the above-mentioned circumstances, and its purpose is to drive the control plate to rotate and to vary the capacity of the compression chamber according to the operating conditions. An object of the present invention is to provide a capacity-controlled gas compressor that enables precise control of a control plate without exerting an adverse effect on the control plate due to high-speed rotation of a rotor.

<<Structure of the invention>> In order to achieve the above object, the present invention includes a cylinder whose inner periphery is formed into a substantially elliptical shape, front and rear side blocks attached to both sides of this cylinder, and the cylinder and both side blocks. A rotor is rotatably suspended horizontally in a cylinder chamber configured as such, and has a plurality of vanes that are movable in the radial direction. A compressor main body consisting of a control plate and a control plate that accommodates the compressor main body, and a space is formed at the rear of the rear side block, in which lubricating oil under discharge pressure is stored, and the rotor is The lubricating oil is supplied to each part of the compressor body by discharge pressure, and at the same time, a portion of the lubricating oil is transferred to vane pressure chambers formed on both the front and rear sides of the rotor. and the contact pressure of the vane against the inner wall of the cylinder chamber is obtained by this hydraulic pressure,
In a gas compressor in which the control plate is rotationally driven to vary the capacity of the compression work chamber in the cylinder chamber according to high-speed or low-speed operation, the internal pressure in the front vane pressure chamber is lower than that in the rear vane pressure chamber. The rotor is biased toward the rear side by increasing .

<<Description of Embodiments>> Preferred embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a longitudinal cross-sectional view showing a first embodiment of the gas compressor according to the present invention, and FIGS. 2 and 3 are longitudinal cross-sectional views showing the respective states of the gas compressor during high-speed operation and low-speed operation. 4 are longitudinal sectional views showing a second embodiment of the gas compressor according to the present invention.

In FIG. 1, this gas compressor includes a compressor main body 1, a casing 2 with an open end that airtightly surrounds the main body 1, and a front head 3 attached to the open end surface of the casing 2. .

The compressor main body 1 has a cylinder 4 having an elliptical inner circumference, a front side block 5 and a rear side block 6 attached to both sides of the cylinder 4, and a substantially elliptic cylindrical cylinder formed thereby. In the cylinder chamber of the rotor 9, a solid cylindrical rotor 9, which is integrated with the rotor shaft 7 and is equipped with five vanes 8 that can move forward and backward in the radial direction around the rotor shaft 7, is rotatably suspended horizontally.

Further, a substantially disk-shaped control plate 10 is pivotally attached to the inner surface of the front side block 5, and the control plate 10 is configured to be rotatable within a predetermined angle.

A recess 11 (intake port) is formed in the peripheral edge of the control plate 10, and the communication hole 12 of the front side block 5 and the cylinder chamber 13 communicate with each other through the recess 11.

In other words, during high-speed operation, the suction pressure decreases, so by rotating the control plate 10, the concave portion 11 moves, and as a result, the capacity of the compression work chamber becomes small, and the suction pressure attempts to increase (second (see figure).

Conversely, during low-speed operation, the suction pressure increases, so the control plate 10 rotates in the opposite direction to the above-mentioned direction, and the recess 11 moves thereby.
The compression work chamber is configured to maximize its capacity (see Figure 3).

When the rotor 9 is rotationally driven by the output from the engine via an electromagnetic clutch (both not shown), the low-pressure refrigerant gas introduced from the intake port 14 provided in the front head 3 is
As shown by the solid arrow in the figure, the high-pressure gas is sucked into the cylinder chamber 13 through the communication hole 12 formed 180 degrees opposite to the front side block, and then compressed within the cylinder chamber 13.
5 and a discharge valve 16, it is discharged into the gap between the cylinder 4 and the inner periphery of the casing 2, and further through a communication hole provided in the rear side block 6 with a phase difference of approximately 90 degrees from the communication hole 12. , is supplied to the oil separator 18 at the back of the rear side block 6, and the oil is supplied to the casing 2 as shown by the dashed arrow in FIG.
The liquid is discharged from the rear space through the discharge port 19 to the outside.

Furthermore, lubricating oil 2 is provided in the space 20 formed between the rear side block 6 and the sealed casing 2.
1 is stored, and this lubricating oil 21 is delivered by discharge pressure to the bearing part of the rotor shaft 7, the bottom of the vane 8, and the front and rear sides of the rotor through the oil supply path 22 formed in the cylinder 4 and both side blocks 5 and 6. The air is supplied to vane pressure chambers 23 formed in the respective areas.

Next, these vane pressure chambers 2, which are the main part of the present invention,
The configuration of No. 3 will be explained.

First, the front side vane pressure chamber 23a is connected to the rotor 9.
is formed between the front end surface of the control plate 10 and the control plate 10;
Lubricating oil 21 is supplied into this front side vane pressure chamber 23a through the oil supply path 22, and constantly presses the rotor 9 toward the rear side with a pressure of Pa. The rear vane pressure chambers include a rear vane pressure chamber 23b formed in the gap between the rear end surface of the rotor 9 and the rear side block 6, and a rear vane pressure chamber 23c formed in the rear end surface of the rotor shaft 7. Like the front side vane pressure chamber 23a, the oil supply path 22
The lubricating oil 21 flows through the rear vane pressure chamber 23.
b, 23c.

Further, the vane pressure chamber 23c formed on the rear end surface of the rotor shaft 7 communicates with the suction chamber 25 through the communication passage 24, and since the suction chamber 25 has a low pressure, the vane pressure chamber 23c is substantially connected to the rotor shaft 7. The pressing force on the rear end surface is small.

Therefore, the pressure that presses the rotor 9 toward the front side is only the internal pressure Pb of the rear vane pressure chamber 23b. On the other hand, on the front side, the pressing force of the mechanical seal spring 27 acts on the rotor 7 toward the rear side, and furthermore, the internal pressure Pa of the front side vane pressure chamber 23a acts on the rear side, so these rotors If we look at the pressure applied to rotor 9 comprehensively, the pressure that presses rotor 9 toward the rear side is much greater than the pressure that presses it toward the front side, so rotor 9 will be biased toward the rear side. .

Therefore, even when the rotor 9 rotates at high speed, the rotor 9 is always biased toward the rear side, so that the control plate 10 is not adversely affected by the high speed rotation of the rotor 9. The rotational position of the compressor can be controlled correctly, and the capacity of the compression work chamber can always be maintained at an appropriate level.

Next, a second embodiment of the gas compressor according to the present invention will be described based on FIG.

In this embodiment, the front side vane pressure chamber 2
6a is formed to have a large diameter, while rear side vane pressure chambers 26b and 26c are formed in the gap between rotor 9 and rear side block 6 or in the rear end surface of rotor shaft 7, respectively. When the lubricating oil 21 is supplied to these front and rear vane pressure chambers 26a, 26b, and 26c through the oil supply path 22, the internal pressure of the front vane pressure chamber 26a is increased by the pressure inside the rear vane pressure chambers 26b and 26c. The mechanical seal spring 2 applied to the rotor shaft 7
Considering that the pressing force by 7 presses the rotor 9 toward the rear side, the pressure that presses the rotor 9 toward the rear side is greater than the pressure that presses it toward the front side, so the rotor 9 is biased toward the rear side. be done.

Therefore, as in the first embodiment, the rotor 9 is always biased toward the rear in this embodiment, and during high-speed rotation, the rotor 9 exerts an adverse influence on the control plate 10.
The control plate 10 is always controlled to an appropriate rotational position, and the capacity of the compression chamber can be maintained at an appropriate level.

<<Effects of the invention>> As explained above, the gas compressor according to the invention is a so-called variable capacity type gas compressor in which the capacity of the compression work chamber is variable by rotating the control plate. The vane pressure of the vane pressure chambers formed on the front and rear sides that press the rotor with a constant pressure is set so that the front side vane pressure is higher than the rear side vane pressure, so the rotor is always attached to the rear side. The rotational position of the control plate is not adversely affected in any way even by high-speed rotation of the rotor, and the control plate can always be held at the appropriate angular position, so the capacity of the compression work chamber can always be maintained at an appropriate value. In addition to increasing the reliability of the equipment, it also has the additional effects of maximizing the sealing between the rotor and control plate and minimizing compression loss.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a gas compressor showing a first embodiment of the present invention, FIGS. 2 and 3 are cross-sectional views showing the same gas compressor during high-speed operation and low-speed operation, respectively. The figure is a longitudinal sectional view of a gas compressor showing a second embodiment of the present invention. 4...Cylinder, 5...Front side block, 6...Rear side block, 8...Vane,
9...Rotor, 10...Control plate, 11...
Recess (intake port), 12... Communication hole, 13... Cylinder chamber, 14... Intake port, 19... Discharge port, 21
...Lubricating oil, 22...Oil supply route, 23, 26...
Vane pressure chamber, 24... communication path, 25... suction chamber.

Claims (1)

[Claims for Utility Model Registration] (1) A cylinder having a substantially elliptical inner circumference, front and rear side blocks attached to both sides of the cylinder, and a cylinder constituted by the cylinder and both side blocks. A compression compressor consisting of a rotor that is rotatably suspended horizontally in a room and has a plurality of vanes that can move forward and backward in the radial direction, and a control plate that is rotatably attached to the inner surface of the front side block so as to be rotatable within a predetermined angle. In addition to accommodating the machine body and the compressor body, a space is formed at the rear of the rear side block, lubricating oil under discharge pressure is stored in this space, and the tip of the rotor shaft of the rotor is rotatable. The lubricating oil is supplied to each part of the compressor main body by the discharge pressure, and at the same time, a part of the lubricating oil is supplied into the vane pressure chambers formed on both the front and rear sides of the rotor. Therefore, in the gas compressor, the contact pressure of the vanes against the inner wall of the cylinder chamber is obtained, and the capacity of the compression working chamber in the cylinder chamber is varied by rotating the control plate according to high-speed or low-speed operation. A gas compressor, characterized in that the rotor is urged rearward by increasing the internal pressure in the front vane pressure chamber compared to the rear vane pressure chamber. (2) By communicating the rear vane pressure chamber with the suction chamber, the internal pressure of the rear vane pressure chamber is reduced, and the internal pressure of the front vane pressure chamber is increased compared to the rear vane pressure chamber. Claim 1 for utility model registration characterized by:
Gas compressor as described in section. (3) Registration of a utility model characterized in that the internal pressure of the front vane pressure chamber is increased compared to the rear vane pressure chamber by setting the pocket chamber that constitutes the front vane pressure chamber to a large diameter. A gas compressor according to claim 1.