JPH0563635B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a gas compressor used in car coolers and the like, and particularly to a gas compressor in which the capacity of its compression work chamber is variable.

(Prior art) A gas compressor used for air conditioning in passenger cars is usually installed in parallel with the engine, and is driven by a V-belt from the engine's crankshaft pulley. The drive connection is made intermittently.

Therefore, the capacity of this type of gas compressor increases in proportion to the rotational speed of the engine, but this means that when driving at high speed, the gas compressor is driven at high speed. As a result, there is a problem in that the interior of the vehicle tends to be overcooled, and the power consumption increases proportionally, resulting in worsening fuel efficiency.Especially with rotary gas compressors, this problem arises. The trend is remarkable.

As a countermeasure for this, the capacity of the refrigerant gas compression chamber is changed according to the driving speed of the gas compressor.
Various so-called variable capacity gas compressors have been proposed.

For example, there is a variable capacity gas compressor related to an earlier application by the present applicant (patent application filed on November 17, 1985). This gas compressor includes a substantially disk-shaped capacity control plate that can rotate within a predetermined angle,
A bypass recess is formed on the periphery of the capacity control plate, and when the gas compressor is driven at high speed, the capacity control plate rotates and the bypass recess communicates with the bypass hole formed in the front side guide block. , a portion of the refrigerant gas in the compression chamber is bypassed into the chamber to reduce the capacity of the compression chamber. As a result, even if the gas compressor is driven at high speed, it is possible to prevent the interior of the vehicle from becoming overcooled, and it is also possible to prevent power consumption from being reduced and fuel efficiency from deteriorating.

Also, inside the radius of the front side block,
A cylindrical stepped portion is formed whose tip protrudes toward the cylinder side and is close to the end surface of the rotor, and has a groove portion serving as a vane pressure chamber on the inner periphery side, and a rotatable capacity control device is formed on the outer periphery of this cylindrical stepped portion. The plates are configured to fit together. As a result, a large amount of refrigerant gas and lubricating oil leak from between the abutting surfaces (diameter contact surfaces) of the capacity control plate and the front side block and flow into the suction chamber.
Furthermore, this lubricating oil is prevented from flowing into the cylinder and deteriorating the performance of the gas compressor.

(Problems to be Solved by the Invention) However, when such a conventional gas compressor is driven at a low speed, as described above, the compressor is compressed from between the abutting surfaces of the capacity control plate and the front side block. This can effectively prevent a large amount of lubricating oil from leaking into the suction chamber and deteriorating the performance of the gas compressor, but on the other hand, when driven at high speed, lubricating oil leaks into the suction chamber and even into the cylinder. The problem is that too little lubrication occurs in various parts, causing the gas compressor to overheat and the temperature of the discharged gas to rise too high, which can cause the entire gas compressor and car cooler to malfunction or significantly deteriorate in performance. It was hot.

(Means for solving the problems) Therefore, in order to solve the above problems, the present invention has the following steps:
A cylinder whose inner periphery is formed into a substantially elliptical shape, a rear scissor block attached to one end of the cylinder, and a rear scissor block attached to the other end of the cylinder whose tip protrudes radially inward toward the cylinder and extends toward the inner circumference. a front side block formed with a cylindrical step having a vane pressure chamber; a capacity control plate rotatably fitted to the outer periphery of the cylindrical step and facing the other end of the cylinder; A rotor whose both end shafts are rotatably supported by a front side block and a rear side block and housed in a cylinder so as to have a rotational axis coaxial with the cylinder; a plurality of vanes biased radially outward of the rotor by the pressure of the rotor to define a compression chamber between the inner periphery of the cylinder and the outer periphery of the rotor; a front head forming a gas suction chamber, and in which the capacity of the compression work chamber is variable according to operating conditions by rotating the capacity control plate, the cylindrical stepped portion has a radius. a notch is formed in a part of the inner periphery of the capacity control plate, and the passage and the notch are formed only when the capacity control plate rotates in a direction that reduces the capacity of the compression work chamber. The vane pressure chamber and the suction chamber are configured to communicate with each other.

(Function) According to the gas compressor having such a configuration, the front side block attached to the other end of the cylinder has a vane on the inner circumferential side with the tip protruding toward the cylinder side and close to the rotor end surface. By forming a cylindrical stepped portion having a pressure chamber, and by rotatably fitting a capacity control plate to the outer periphery of this cylindrical stepped portion and arranging it to face the other end of the cylinder, gas compression is achieved. When the machine is driven at low speed, it is possible to effectively prevent a large amount of lubricating oil from leaking between the abutting surfaces of the capacity control plate and the front side block, thereby preventing the performance of the gas compressor from deteriorating.

In addition, a passage is formed in the radial direction in the cylindrical stepped portion, and a notch is formed in a part of the inner circumference of the capacity control plate, so that only when the capacity control plate rotates in a direction that reduces the capacity of the compression work chamber, Since the passage and the notch communicate with each other to communicate the vane pressure chamber and the suction chamber, when the gas compressor is driven at high speed, a large amount of lubricating oil is supplied from the vane pressure chamber to the suction chamber, and this Lubricating oil is supplied into the cylinder from the suction chamber to cool each part and lower the temperature of the discharged gas. This prevents overheating of the gas compressor or rise in discharge gas temperature due to insufficient lubrication during high-speed operation of the gas compressor, effectively preventing failure or significant performance deterioration of the gas compressor or car cooler as a whole. be able to.

(Example) Hereinafter, an example of the present invention will be described based on the drawings. 1 to 8 are diagrams showing a first embodiment of a gas compressor according to the present invention.

First, to explain the structure, in Fig. 1, 1 is a casing with an open end on the right side in the figure;
A cylinder 2 is housed within the casing 1, and the inner periphery of the cylinder 2 is formed into a substantially elliptical shape as shown in FIG. A rear side block 3 is attached to one end of the cylinder 2 (the left end in FIG. 1), and a front side block 5 is attached to the other end of the cylinder 2 (the right end in FIG. 1). A cylindrical stepped portion 5a is formed radially inward (center side) of the front side block 5, and the tip of this cylindrical stepped portion 5a is connected to the cylinder 2.
protrudes to the side. A capacity control plate 6 is rotatably fitted to the outer periphery of the cylindrical step portion 5a, and this capacity control plate 6 is arranged to face the other end of the cylinder 2. A thrust bearing 14 is interposed radially inward between the abutting surfaces of the front side block and the capacity control plate 6 so that the capacity control plate 6 rotates smoothly. A rotor shaft 8 protruding from both ends of the rotor 7 is attached to the rear side block 3 and the front side block 5.
a and 8b are rotatably supported, so that the rotor 7 is housed in the cylinder 2 so as to have its axis of rotation coaxially with the cylinder 2. rotor 7
As shown in FIGS. 2 and 3, five grooves 10 are formed at equal intervals in the circumferential direction and extend in the same direction as the axis of the rotor 7.
A vane 11 is supported inside the rotor 7 so as to be movable in the radial direction of the rotor 7. A vane pressure chamber 12 is formed on the inner peripheral side of the cylindrical step portion 5a, as shown in FIG. 1 and FIGS. Back pressure chamber 1
It communicates with 0a. Therefore, the vane pressure of the pane pressure chamber 12 acts on the back pressure chamber 10a, urging the vane 11 outward in the radius of the rotor 7, so that the tip of the vane 11 is always on the inner circumference of the cylinder 2. It rotates together with the rotor 7 while being in contact with each other. In Figures 4 and 5, the vane pressure chamber 12 appears to be separated into two upper and lower chambers, but this is to prevent so-called chattering of the vane 11, and these are communicated by a passage not shown. ing. Then, as shown in Figure 2, two adjacent
The vanes 11 define a compression chamber 13 between the inner circumference of the cylinder 2 and the outer circumference of the rotor 7 . Also,
As shown in the figure, a pair of discharge ports 19 are formed in the cylinder 2, and a discharge valve 23 is provided on the outside of each of the discharge ports 19.

On the opposite side of the front side block 5 from the cylinder 2, there is a suction chamber 1 for refrigerant gas (gas) therein.
A front head 16 forming a front head 5 is attached. As shown in FIG. 7, a pair of communication holes 17 and a pair of bypass holes 18 are opened in the front side block 5, and a pair of communication holes 17 and a pair of bypass holes 18 are formed on the end surface of the cylinder 2 facing the communication holes 17, as shown in FIG. An intake passage 20 extending parallel to the axis is opened. Communication hole 17 of front side block 5
An intake recess 21 having the same shape as the communication hole 17 is formed in the portion of the rear side block 3 facing the rear side block 3.
This intake recess 21 communicates with the intake passage 20 and also with the inside of the cylinder 2. As shown in FIGS. 4, 5, and 7, a pair of recesses 22 are formed in the capacity control plate 6 at symmetrical positions with respect to each other, and these recesses 22 are connected to the intake passage 20 when the capacity control plate 6 does not rotate. and the communication hole 17, and when the capacity control plate 6 rotates as will be described later, the recess 22 communicates with the bypass hole 18, as shown in FIGS. 3 and 8.

An oil separation chamber 24 is defined in the casing 1 on the side opposite to the cylinder 2 with respect to the rear side block 3, and an oil separator 25 is provided on the rear side block 3 side of the oil separation chamber 24. The lubricating oil accumulated below the oil separation chamber 24 passes through the oil supply passage 26 formed in the thick walls of the rear side block 3, cylinder 2, and front side block 5 to the lubricating parts of the rotor shafts 8a and 8b and the vanes. It is adapted to be supplied to the pressure chamber 12.

Inside the suction chamber 15, as shown in FIG. The other end 28b faces the outside of the front head 16. Drive cylinder 28 and front head 1
A spring 30 is interposed between the
This spring 30 always biases one end portion 28a of the drive cylinder 28 in the direction of protruding into the suction chamber 15 by its spring pressure. A drive pin 31 is provided upright on the capacity control plate 6.
1 passes through a guide hole 32 formed in an arc shape in the front side block 5, and the tip of this drive pin 31 is connected to one end 28 of the drive cylinder 28.
It always engages with the engagement recess 34 formed in a.

As shown in Figures 1, 4, 5, and 8, the cylindrical step 5
A has a round hole passage 35 formed in its radial direction, while the capacity control plate 6 has a hole on its inner circumference on the side of the suction chamber 15, as shown in FIGS. A notch 40 is formed in the portion. Furthermore, as shown in FIG. 6, the notch 40 has the same width over its entire length.

Next, the effect will be explained. The low-temperature, low-pressure refrigerant gas sucked into the suction chamber 15 from an evaporator (not shown) is sucked into the cylinder 2 from the communication hole 17 through the intake passage 20 and the intake recess 21, or directly from the communication hole 17, and is then sucked into the cylinder 2 from the communication hole 17. The vane 11 that rotates with the compressor 7 compresses the air in the compression work chamber 13 and becomes high temperature and high pressure, and the discharge port 19 and the discharge valve 2
3 and is discharged into the oil separation chamber 24. At this time, the refrigerant gas is separated from the lubricating oil by the oil separator 25, and the lubricating oil accumulates below the oil separation chamber 24, and the high temperature and high pressure refrigerant gas is sent from the oil separation chamber 24 to a condenser (not shown). .

When the rotor 7 is rotating at a low speed, the capacity control plate 6 is in the position shown in FIG. 2, so the compression chamber 13 compresses the refrigerant gas at its maximum capacity. The lubricating oil in the oil separation chamber 24 is supplied to the lubricating parts of the rotor shafts 8a, 8b and the vane pressure chamber 12 through the oil supply path 26, but when the rotor 7 is rotating at a low speed, the capacity control plate 6 is in the position shown in FIG. 4, so the passage 35 and the notch 40 do not communicate with each other. Therefore, a large amount of lubricating oil in the vane pressure chamber 12 is prevented from leaking from between the abutting surfaces of the capacity control plate 6 and the front side block 5, and the performance of the gas compressor is prevented from deteriorating. It can be effectively prevented.

When the rotor 7 rotates at high speed, the suction pressure in the suction chamber 15 decreases, so the spring pressure of the spring 30 overcomes the suction pressure, and the drive cylinder 28 moves into the suction chamber 15.
The drive pin 31 is rotated within a predetermined angle along the guide hole 32 (proceeding further toward the upper left in FIG. 7). Therefore, the capacity control plate 6
The recess 22 rotates together with the drive pin 31 so that the recess 22 communicates with the bypass hole 18, thereby reducing the capacity of the compression chamber 13 as shown in FIG.
This can prevent the discharge capacity of the gas compressor from becoming small and overcooling the interior of the vehicle during high-speed driving, and can also prevent power consumption from decreasing and fuel efficiency from worsening. can. Furthermore, when the rotor 7 rotates at high speed, the capacity control plate 6 rotates as described above, so the fifth and eighth
As shown in the figure, the passage 35 and the notch 40 communicate with each other, and the lubricating oil in the vane pressure chamber 12 is actively leaked between the combined surfaces of the capacity control plate 6 and the front side block 5, and a large amount is supplied. 8th
It flows into the suction chamber 15 as shown by the arrow in the figure.
The lubricating oil is further supplied into the cylinder 2 from the suction chamber 15 to perform a cooling and sealing action on each part, thereby lowering the temperature of the discharged gas. This prevents overheating of the gas compressor or rise in discharge gas temperature due to lack of lubrication in various parts during high-speed operation, and effectively prevents failure or significant performance deterioration of the gas compressor or car cooler as a whole.

Further, according to this embodiment, the vane pressure chamber 12
By actively leaking the lubricating oil inside to the suction chamber 15 side, the force of the vane pressure difference 12 is slightly lowered, but when the rotor 7 rotates at high speed, centrifugal force acts on the vane 11, so the tip of the vane 11 is pushed into the cylinder. 2
There is no need to worry about the blade separating from the inner periphery of the vane 11. Rather, by using the minimum necessary pressing force, it is possible to prevent unreasonable pressing torque from acting on the tip of the vane 11, thereby reducing power consumption and improving fuel efficiency.

FIG. 9 shows a second embodiment of the present invention.
In the first embodiment, the notch 40 had the same width over its entire length, but in the second embodiment, the width of the notch 40' increases as it rotates. It is structured in such a way that it extends widely.
According to the second embodiment, the notch 40' gradually expands the cross-sectional area of communication with the passage 35.
According to changes in the suction pressure in the suction chamber 15, the required amount of lubricating oil can be supplied when required.

In the above embodiment, the passage 35 is a round hole, but the cross-sectional shape of the passage 35 may be a slit or other shape.
Further, in the above embodiment, the capacity control plate 6
Although the notch 40 is formed to open toward the suction chamber 15 side, the notch 40 may be formed to open toward the rotor 7 side, or may be formed to open to both sides. However, it is easier to supply lubricating oil to the suction chamber 15 with an opening toward the suction chamber 15 as in the above embodiment, and it is considered that this is most suitable for the purpose of the present invention.

(Effects of the Invention) As explained above, according to the present invention, when the gas compressor is driven at low speed, a large amount of lubricating oil leaks from between the abutting surfaces of the capacity control plate and the front side block. It is possible to effectively prevent the performance of the gas compressor from deteriorating, and when the gas compressor is driven at high speed, a large amount of lubricating oil is supplied from the vane pressure chamber to the suction chamber, and the lubricating oil is further absorbed into the suction chamber. The gas is supplied from the chamber into the cylinder to cool each part and lower the temperature of the discharged gas. This prevents overheating of the gas compressor or rise in discharge gas temperature due to insufficient lubrication of various parts during high-speed operation of the gas compressor, effectively preventing failure or significant performance deterioration of the pneumatic compressor or car cooler as a whole. It can be prevented.

In addition, the minimum necessary pressing force is applied to the tip of the vane, preventing unreasonable pressing torque from being applied, thereby reducing power consumption and improving fuel efficiency.

[Brief explanation of the drawing]

1 to 8 are diagrams showing a first embodiment of a gas compressor according to the present invention, and FIG. 1 is a cross-sectional side view thereof;
Figures 2 and 3 are sectional views taken along the - arrow in Figure 1;
Figures 4 and 5 are sectional views taken along the - arrow in Figure 1;
Figure 6 is a sectional view taken along the - arrow in Figure 5;
The figures are a cross-sectional view taken in the direction of the − arrow in FIG. The figure shows the second aspect of the present invention.
It is a partial sectional view showing an example. DESCRIPTION OF SYMBOLS 1... Casing, 2... Cylinder, 3... Rear side block, 5... Front side block, 5a... Cylindrical step, 6... Capacity control plate, 7... Rotor, 8a, 8b... Rotor shaft ,1
0... Groove, 10a... Back pressure chamber, 11... Vane,
12...Vane pressure chamber, 13...Compression work chamber, 1
4... Thrust bearing, 15... Suction chamber, 16...
Front head, 17... Communication hole, 18... Bypass hole, 19... Discharge port, 20... Intake passage, 21... Intake recess, 22... Recess, 23...
Discharge valve, 24... oil separation chamber, 25... oil separator,
26... Oil supply path, 28... Drive cylinder, 28
a...One end, 28b...Other end, 30...Spring, 31...Drive pin, 32...Guide hole,
34... Engaging recess, 35... Passage, 40, 40'
...notch.

Claims (1)

[Claims] 1 A cylinder whose inner periphery is formed into a substantially elliptical shape, a rear side block attached to one end of the cylinder, and a rear side block attached to the other end of the cylinder whose tip protrudes radially inward toward the cylinder and extends toward the inner circumference. a front side block formed with a cylindrical step having a vane pressure chamber; a capacity control plate rotatably fitted to the outer periphery of the cylindrical step and facing the other end of the cylinder; A rotor whose both end shafts are rotatably supported by a front side block and a rear side block and housed in a cylinder so as to have a rotational axis coaxial with the cylinder; a plurality of vanes biased radially outward of the rotor by the pressure of the rotor to define a compression chamber between the inner periphery of the cylinder and the outer periphery of the rotor; and a front head that forms a gas suction chamber, and in which the capacity of the compression work chamber is variable according to the operating state by rotating the capacity control plate, the cylindrical stepped portion has a radial direction. and a notch is formed in a part of the inner periphery of the capacity control plate, and the passage and the notch are formed only when the capacity control plate rotates in a direction that reduces the capacity of the compression work chamber. A gas compressor characterized in that the vane pressure chamber and the suction chamber are communicated with each other.