JPS6248982A - Variable displacement rotary compressor - Google Patents

Abstract

PURPOSE:To vary a discharge securely and continuously with a relatively simple construction by rotatably fitting a rotary blade having a port which serves as an intake passage when overlapped with a part of an intake port, on a housing side plate on which said intake port is provided. CONSTITUTION:When a gear 44 is rotated in the direction of the arrow accompanying the rotation of a motor, a rotary blade 40 which is rotatably fitted to the side plate 20 of a housing, is rotated in the same direction as the rotating direction of a rotor 12. A port 40d provided on the rotary blade 40 forms an intake passage when it is overlapped with a part of an intake port 20d provided on the side plate 20. And, the position of one end of the intake passage which is formed when the intake port 20d is overlapped with the port 40d, is continuously moved from a point A to a point B and to a point C as shown in the figure. Accordingly, connection between the cylinder chamber R and the intake passage is cut off and a position in which a compression stroke is started, is moved in the direction in which the capacity of the chamber R is reduced, to compress and discharge a refrigerant in a small-capacity cylinder chamber R. Thereby, a discharge can be varied securely and continuously with a relatively simple construction.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a variable capacity rotary compressor, and is effective for use as a compressor for compressing refrigerant in, for example, an automobile air conditioner.

[Conventional technology]

In recent years, there has been an increasing need to reduce the driving force of compressors having vanes, and variable capacity compressors that can change the discharge capacity have been proposed. These devices provide a bypass passage that communicates the compression cylinder chamber and the suction chamber, and control the opening and closing of this passage, or control the rotation of a ring having a bypass port device (for example, U.S. Pat. No. 4,137,0
According to a method such as No. 18), the gas once sucked into the cylinder chamber is bypassed to the suction chamber or the like and returned again, thereby controlling the discharge volume to a small value.

However, in conventional systems, there is a limit to the maximum cross-sectional area of the passages, etc., so once the gas is sucked into the cylinder chamber, it is constricted by the passages, etc., making it virtually impossible to efficiently return it to the suction chamber. It was very effective. especially,
In the high rotation range of the compressor, the gas in the cylinder chamber is compressed and discharged without being sufficiently returned to the suction chamber, so that the discharge capacity cannot be reduced. In other words, there is a problem in that the discharge capacity cannot be changed over a wide rotation range.

[Problem that the invention seeks to solve]

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a variable capacity rotary compressor that changes the discharge capacity over a wide rotation range from a low rotation range to a high rotation range.

[Means for solving problems]

Therefore, as a means for solving the above-mentioned problems, the present invention provides a rotary compressor in which a rotatable rotary plate is fitted into the side plate of the housing in which the suction hole is provided, and a part of the suction hole is fitted into a part of the rotary plate. The present invention is characterized in that an opening that overlaps with the rotary plate is provided, and a rotation driving means for controlling the rotation of the rotary plate is provided.

[Effect]

According to the above configuration, by controlling the rotation of the rotary plate, the position where the suction hole and the opening of the rotary plate overlap, that is, the substantial position of the suction path, moves in the rotational direction of the rotor. Therefore, the timing at which the compression stroke of the cylinder chamber starts, that is, the rotation angle of the rotor at which communication between the cylinder chamber and the substantial suction path is cut off, changes, and the discharge capacity of the compressor can be changed.

〔Example〕

A first embodiment of the present invention will be described below based on the drawings.

In FIGS. 1 and 2, 10 is a substantially cylindrical inner wall surface 1.
0a, and 12 is a cylindrical rotor eccentrically disposed within the housing 10. The rotor 12 rotates integrally with a rotating shaft 14 fixed to the University of Technology. Also,
Two slit grooves 16 are provided in the rotor 12 in the radial direction so as to be perpendicular to each other, passing through the center of the rotor 12, and vanes 18 are slidably inserted and held in the slit grooves 16. ing. Further, the image tip of the vane 18 is always in sliding contact with the inner wall surface 10.2. Furthermore, vane 18
are shaped so that their sliding movements in the radial direction do not interfere with each other.

Housing side plates 20 and 22 are fixed to the sides of the housing 10 via seal members (not shown), and the rotating shaft 14
The bearing 24.2 is attached to this housing side plate 20.22.
It is rotatably supported via 5. Therefore, the housing side plate 20, the housing inner wall surface 10a, and the rotor 1
2. A cylinder chamber R is defined by two adjacent vanes 18 and the like. The fluid, such as refrigerant, compressed in this compression cylinder chamber R as the rotor 12 rotates, is transferred to a discharge chamber 30 that communicates with the fluid through a discharge port 26 and a discharge valve 28.
is discharged to.

A front housing 32 is closely fixed to the housing side plate 20, and the housing side plate 20 and the front housing 3
2 is defined as a suction chamber 34.

The suction chamber 34 has a suction passage 36 that introduces the refrigerant.
It communicates with a refrigeration cycle (not shown). Note that 38 is a shaft sealing device that prevents fluid from flowing out.

As shown in FIG. 3, a rotary plate 40 is fitted into the housing side plate 20 so as to rotate smoothly. As shown in FIG. 4, the housing side plate 20 has a ring portion 20a and an annular recess 20b concentrically with the rotating shaft 04) in the center thereof.
A circular recess 20C in which a gear (44) is accommodated is provided adjacent to the recess 20b.

Further, the recess 20b of the housing side plate 20 has a suction chamber (3
4) is provided with a suction hole 20d that is open and communicates with the compression cylinder chamber (R). This suction hole 20d is
It has a crescent shape surrounded by an arcuate surface 20e along the outer peripheral surface of the rotor (2) and an arcuate surface 20f along the inner peripheral surface (10a) of the housing QOI. The position where the suction hole 20d is provided is on the opposite side of the discharge port (26) with respect to the central axis of the rotation axis Oa, and the angle α thereof is set to about 180°. Note that this angle α is substantially equal to the cylinder chamber R.
It is determined by the number of This is a range in which the cylinder chamber (R) does not communicate with the suction hole 20d and the discharge port (26) at the same time in the stroke in which the volume of the cylinder chamber (R) decreases, and the cylinder chamber (R) is spaced four times at equal intervals. In this embodiment, the suction hole 20d is provided within a range of about 270° from the position of the discharge port (26) in the rotational direction of the rotor.

The disk-shaped rotating plate 40 has an opening 4 as shown in FIG.
0a, and a circular hole 40b that fits into the ring portion 20a of the housing side plate 20. The angle β at which the opening 40a is formed is set to be equal to or smaller than the angle α at which the suction hole 20d is formed. Also, the opening 40
A gear 44 is provided on the circumferential surface opposite to the circumference where a is provided.
Interlocking teeth 40C are provided. This opening 40a
A part of the housing side plate 20 is provided so as to overlap the suction hole 20d of the housing side plate 20 to form a suction passage in a normal position.

The rotary plate 40 is fitted into the recess 2Ob of the housing side plate 20 so as to rotate smoothly using the ring portion 20a as a shaft, and the rotary plate 40 is rotated by a gear 44 meshing with teeth 40C on the outer periphery of the rotary plate 40. be done. The gear 44 is a motor 42 fixed coaxially with the rotating shaft 14.
The rotation is controlled in the forward and reverse directions. Although the mounting positions of the motor 42 and gear 44 in FIG. 1 are different from the actual mounting positions, they are actually mounted at the position of the gear 44 shown in FIG. 3.

As shown in FIG. 6, the motor 42 is controlled to rotate forward, stop, and reverse by switching a double-pole, double-throw contact 48 of a thermoswitch (not shown) that operates depending on the refrigerant temperature of the evaporator. For example, if the refrigerant temperature in the evaporative lake is Q'c
When it becomes less than 1, the contact 48 switches to the D2 side, and the motor 42 rotates normally (in the direction of the arrow shown by the gear 44 in FIG. 3). Also, if the refrigerant temperature in the evaporator is 0°C or higher and 2°C
When the contact point 48 is less than N1. Switched to N2, motor 4
2 is stopped and the temperature is above 2°C, the contact 48 is closed to U.
.

Switching to the U2 side, the motor 42 rotates in reverse.

Next, the operation of the variable capacity rotary compressor having the above configuration will be explained.

When the rotating shaft 14 rotates, receiving a driving force from a driving source (not shown) such as an automobile engine, this rotation causes the rotor 1 to rotate.
2 and the vane 18 rotate, and the cylinder chamber R changes its volume. In this process of increasing the volume, the suction chamber 3 is
4, the refrigerant is introduced into the suction hole 2 of the housing side plate 20.
The air is sucked into the cylinder chamber R through a suction path formed by overlapping Od and the opening 40a of the rotary plate 40. Then, this refrigerant is cut off from the suction passage as the rotor 12 etc. rotate, and is then compressed in the compression stroke in which the volume of the compression cylinder chamber R is reduced.Furthermore, in the state where the volume of the cylinder chamber R has been reduced the most, the refrigerant is opened at the discharge port. 26 and is discharged into the discharge chamber 3o via the discharge valve 28.

The refrigerant discharged into the discharge chamber 30 flows out to the oil separator 52 in the rear housing 50 via the discharge communication hole 22a provided in the housing side plate 22, and
After the lubricating oil is separated and removed in step 2, it is discharged through a discharge passage 54 to a condenser of a refrigeration cycle (not shown).

When the compressor is operated in a steady state, the motor 42 is not energized, so the suction hole 20d of the housing side plate 20 and the opening 40a of the rotary plate 40 overlap as shown in FIG. is forming. Therefore, in a steady operating state, after the vane 18 passes point A as the rotor 12 rotates, communication between the cylinder chamber R and the suction path is cut off, and a compression stroke begins, and the suction is sucked into the cylinder chamber R, which has the maximum volume. The same amount of refrigerant is compressed and discharged.

Next, when the compressor's discharge capacity is excessive compared to the requirements of the refrigeration cycle, such as when the engine is running at high speed, or when accelerating or even overheating, the refrigerant temperature in the evaporator, The state is detected by an internal temperature detection sensor, a low-pressure refrigerant pressure signal of the refrigeration cycle, a vehicle speed sensor, an engine speed detection sensor (not shown), an engine cooling water temperature, etc., and the contact 48 is switched to the D+ or Dz side to start the motor 42. Rotate forward. When the gear 44 rotates together with the motor 42 in the direction of the arrow in FIG.
The position of one end of the suction passage formed by the overlapping of the opening 40d and the opening 40d moves continuously from point A to point B to point C, as shown in FIG. Therefore, the position where the communication between the cylinder chamber R and the suction path is cut off and the compression stroke starts moves in the direction in which the volume of the cylinder chamber R decreases, and a small volume of refrigerant in the cylinder chamber R is compressed and discharged. It turns out.

By rotating the rotary plate 40, the starting position of the compression stroke moves continuously from point A to point B to point C, so that the discharge capacity of the compressor is continuously controlled from the maximum to the minimum capacity. .

Further, when the discharge capacity of the compressor is small compared to the requirements of the refrigeration cycle, the contact 48 is switched to the U+ and 'Uz sides, and the motor 42 and rotating plate 40 are reversed in the opposite direction to the above-mentioned direction to increase the discharge capacity. .

Furthermore, when starting the compressor in a stopped state, the motor 42 is controlled so that the discharge capacity of the compressor is minimized. As a result, the starting load for starting the compressor is reduced, and the shock at the time of starting is reduced. Furthermore, this control can prevent liquid compression, that is, a phenomenon in which liquefied refrigerant is compressed and abnormally high pressure is generated.

Incidentally, instead of the rotary plate 40 of the above-described embodiment, a rotary plate having fan-shaped openings 40'a as shown in FIG. 7 may be used. Also, an opening 40a.

A part of 40'a is the suction hole 20 of the housing side plate 20.
It may be of any other shape as long as it overlaps with a to form a suction passage and the position of one end of the suction passage moves as the rotary plate rotates.

In addition, as a rotation means other than the above-mentioned motor that rotationally drives the rotary plate 40, an electromagnetic Kunia solenoid or a piston linearly driven using refrigerant pressure can be used to press the rotary plate from the tangential direction of the rotary plate. It is also possible to rotate. Further, the rotating plate can be rotated forward in one direction by using a rotation drive means, and the rotating plate can be rotated in the reverse direction by using a spring or the like.

〔Effect of the invention〕

In the variable capacity rotary compressor of the present invention described above, a rotary plate having an opening that overlaps a part of the suction hole and forms a suction path is rotatably fitted into the housing side plate provided with the suction hole. , and by rotating this rotary plate, the volume of the cylinder chamber at the beginning of the compression stroke is changed to change the discharge capacity, so some of the fluid sucked into the cylinder chamber is transferred to the suction chamber, unlike conventional methods. Discharge capacity can be changed without bypassing to. Therefore, the present invention solves the conventional problem that in the high rotation range, the fluid in the cylinder chamber once sucked is difficult to bypass to the suction chamber, so the discharge capacity cannot be reduced. The discharge capacity can be varied over a wide range. Furthermore, since the rotary plate with holes is rotatably arranged, it has the excellent effect of being able to reliably and continuously change the discharge volume with a relatively simple structure. .

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical sectional view showing an embodiment of a variable displacement rotary compressor of the present invention, FIG. 2 is a partial cross-sectional view thereof, and FIG. 3 is a configuration diagram showing a shape along Ii in FIG. 1. Figure 4 (al is a front view of the housing side plate, Figure 4 (bl is a sectional view taken along the no-n line of Figure 4 (BL), Figure 5 (a) is a front view of the rotating plate, Figure (bl is Figure 5 (al m-o-m)
6 is a cross-sectional view along the line, and FIG. 6 is a diagram for explaining the rotational operation of the motor. FIG. 6(a) is a diagram showing the relationship between the evaporator temperature and the contact points, and FIG. 6(b) is a diagram showing the motor control. A circuit diagram showing the circuit, FIG. 7 is a front view of another rotary plate.

Claims (2)

[Claims] (1) A cylindrical housing, a housing side plate disposed to cover the open end of the housing, a rotor rotatably disposed within the housing eccentrically from the inner surface of the housing, and a rotor that slides on the rotor. and a plurality of freely held vanes, which sucks fluid through a suction hole provided in the housing side plate by varying the volume of a cylinder chamber formed by the housing, the housing side plate, the rotor, and the vanes. In a rotary compressor that performs compression and then discharges into a discharge chamber, a rotatable rotary plate is fitted into a side plate of the housing in which the suction hole is provided, and a part of the rotary plate has an opening that overlaps a part of the suction hole. A variable capacity rotary compressor, characterized in that a hole is provided and a rotational drive means for rotationally controlling the rotary plate is provided. (2) The variable displacement rotary compressor according to claim 1, wherein the opening has a fan shape centered on the rotation axis of the rotor.