JP2000283062A - Rotary compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure the passage area of a discharge port without extending the diameter of the discharge port to reduce the pressure loss by bringing the discharge port for a compressed fluid into contact with the side surface of a blade oscillated most to a compression chamber side, and arranging it on at least either one of a frame and a cylinder head in a specified position. SOLUTION: A piston 5 revolves along the inner wall of a cylinder chamber in a cylinder 4 so as to oscillate with the central point on the circumferential surface of a guide 28 as a fulcrum through a blade 501, and compress and discharges a fluid through a discharge port 301. The discharge port 301 is arranged in a position where it makes contact with the side surface of the blade 501 in the maximum rocking angle to the compression chamber 402a side, when axially seen, and the inside surface of the cylinder chamber. Namely, the discharge port 301 is arranged in the position where the distance from the center of the cylinder 4 to the center of the discharge port 301 corresponds to the value obtained by subtracting the discharge port radius from the cylinder inside radius. According to this, the discharge port 301 is prevented from being blocked by the blade 501 in the first half of the discharge stroke to reduce the passage area.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary compressor having a piston integrally provided with blades for use in a refrigeration and air conditioning system, and more particularly to a discharge port of the rotary compressor.

[0002]

2. Description of the Related Art FIGS. 7, 8 and 9 show, for example, Japanese Unexamined Patent Publication No. 9-88854.
FIG. 1 is a cross-sectional plan view, a longitudinal side view, and an entire longitudinal side view of the vicinity of a discharge port of a conventional rotary compressor of a blade-integrated piston type disclosed in Japanese Patent Application Laid-Open Publication No. H11-157,026. In the figure, a cylinder having a cylinder chamber 402 in which an inlet port and an outlet port 301, 701 open.
4 and a piston 5 which is formed integrally with a reciprocating and oscillating blade 501 which partitions the inside of the cylinder chamber 402 into a compression chamber 402a and a low-pressure chamber 402b, and which revolves with eccentricity and oscillation in the cylinder chamber 402. A guide 28 rotatably fitted into a cylindrical hole 401 formed on the outer periphery of a cylinder chamber 402 of the cylinder 4 and supporting the blade 501 in a reciprocating and swingable manner. A drive shaft 6 to revolve,
The closed casing 1 is provided with a frame 3 and a cylinder head 7 which are disposed so as to close the openings at both end surfaces of the cylinder chamber 402 and rotatably support the drive shaft 6, and the piston 5 revolves and sucks when the drive shaft 6 rotates. The fluid sucked into the cylinder chamber 402 from the port is compressed and discharged from the discharge ports 301 and 701.

According to the publication, the discharge port is made as close as possible to the compression end position of the piston so as to be openable, thereby delaying the crank angle at which the discharge valve starts discharging to reduce the reactive power of the piston. As shown in FIGS. 7 and 8, at least a part of the discharge ports 301 and 701 of the cylinder 4 facing the outer periphery of the guide 28 on the compression chamber 402a side from the blade 501 and the outer periphery thereof as shown in FIGS. It is provided so as to overlap the part, and guides so that the compression chamber 402a communicates with the discharge ports 301 and 701 at the compression end position of the piston 5.
28 The outer peripheral portion of the guide 28 on the side of the discharge ports 301 and 701 over the overlap portion with the discharge ports 301 and 701 of the outer peripheral portion and the overlap portion with the discharge ports 301 and 701 of the cylinder 4 Notches 404 are provided by notching the four surfaces, respectively.

[0004] In this modification, the overlap portion of the cylinder with the discharge port of the outer peripheral portion of the guide and the overlap portion of the cylinder with the discharge port of the cylinder occupy a larger ratio in the area, and the compression of the piston ends. In the figure, a notch provided so that the compression chamber communicates with the discharge port at the position is formed such that only the cylinder surface of the overlap portion with the discharge port of the cylinder is cut. The discharge port is provided so that at least a part of the discharge port overlaps with the outer peripheral portion of the piston when viewed from the axial direction at the compression end position of the piston. Notched portion is provided by notching the overlap portion of the outer peripheral portion of the piston with the discharge port, and at least a part of the discharge port when viewed from the axial direction is the outer peripheral portion of the guide closer to the compression chamber than the blade and the outer peripheral portion thereof. The piston is provided so as to overlap the outer peripheral portion of the piston at the position of the cylinder opposite to the piston and at the end of compression of the piston, so that the compression chamber communicates with the outlet at the end of compression of the piston. Cut the outer periphery of the guide on the discharge port side and the cylinder surface over both overlapped portions at the overlap portion with the discharge port of the piston and the piston. Notch is also shown that is provided.

[0005]

In the conventional rotary compressor of the blade-integrated piston type shown in FIGS. 7, 8 and 9, or its modified example, the crank angle at which the discharge valve starts discharging is delayed so that An object of the present invention is to enable the discharge port to be opened as close as possible to the compression end position of the piston in order to reduce the reactive power. The intention is to suppress power loss that continues to be caused by the compression of the compression chamber even after the seal point between the piston outer circumference and the cylinder inner circumference passes through the discharge port and the discharge port communicates with the low-pressure chamber side.

However, as the power loss due to the periphery of the discharge port, the discharge pressure loss caused by the discharge resistance immediately after the start of discharge is larger than the loss due to invalid compression at the completion of the compression / discharge process as described above. FIG. 10 shows the so-called P which shows the pressure in the compression chamber in the compression / discharge process on the vertical axis against the volume on the horizontal axis.
It is a diagram schematically showing a V diagram. In the figure, when the pressure in the compression chamber reaches the high pressure Pd of the circuit of the refrigeration cycle at point A, the discharge valve opens and the fluid in the compression chamber starts discharging. A
The point depends on the operating conditions of the circuit.
It is about 70 ゜. At this time, the power required for the pressure in the compression chamber to be higher than Pd due to the resistance of the discharge port becomes a loss called overshoot loss. On the other hand, an invalid compression loss at the time of completion of the compression / discharge process occurs near the point B (crank angle 360 °) where the volume of the compression chamber approaches 0.
In general, in a rotary compressor, including a piston with blade integral piston type, in which the piston is eccentric and revolves in the cylinder chamber, the absolute value of the volume change rate of the compression chamber becomes maximum around 180 ° crank angle and almost zero near 360 °. However, as the flow velocity increases, the loss near point A becomes larger than the loss near point B.

Therefore, in order to prevent the efficiency of the compressor from decreasing, it is more effective to reduce the overshoot loss immediately after the start of discharge than to reduce the invalid compression loss at the completion of the compression / discharge process. To reduce the discharge pressure loss in order to reduce the overshoot loss, it is necessary to secure a flow path area for the discharge port. However, if only the discharge port diameter is increased, the fluid will not be discharged even when the compression is completed. Therefore, it is necessary to secure a flow path area with a minimum required discharge port diameter and avoiding blockage by other components as much as possible.
With the conventional blade-integrated piston type rotary compressor,
The discharge port position determination for securing the discharge port flow area immediately after the pressure in the compression chamber reaches a high pressure and starting the discharge to reduce the pressure loss, taking into account that the blade is integrated,
It was hard to say that it was being done. For this reason, there is a problem that even if the invalid compression loss at the time of completion of the compression / discharge process is reduced, the pressure loss immediately after the start of discharge, which has a larger loss, is not sufficiently reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and takes into account the characteristics of the integral blade, without excessively increasing the diameter of the discharge port. An object of the present invention is to obtain a highly efficient blade-integrated piston type rotary compressor by securing a flow path area and reducing pressure loss.

Although the loss of the ineffective compression at the completion of the compression / discharge process is smaller than the overshoot loss, if the compression chamber immediately before the completion of the compression / discharge becomes an invalid compression space, the lubricating oil mixed in the fluid to be compressed is lost. Therefore, it is necessary that a minimum flow path is secured between the discharge port and the compression chamber until the compression / discharge is completed, without closing the compression chamber.

Therefore, according to the present invention, the compression / compression is performed while the pressure loss is reduced by securing the area of the discharge port flow path immediately after the start of discharge.
It is another object of the present invention to provide a blade-integrated piston type rotary compressor that ensures a minimum flow path until the discharge is completed, reduces overshoot loss, avoids oil compression, and has high efficiency and low noise.

[0011]

In order to achieve the above object, a blade-integrated piston type rotary compressor according to claim 1 of the present invention has a blade provided integrally with a piston. In a rotary compressor, the discharge port is in contact with the side of the blade when it swings most toward the compression chamber when viewed from the axial direction of the frame or cylinder head, and the distance from the cylinder center at the center of the discharge port is determined by the radius inside the cylinder. It is provided at at least one of the frame and the cylinder head at a position not less than the value obtained by subtracting the discharge port radius and not more than the cylinder inner radius.

According to a second aspect of the present invention, there is provided a rotary compressor having a blade provided integrally with a piston, wherein a discharge port is viewed from an axial direction of a frame or a cylinder head. And at least one of the frame and the cylinder head at a position in contact with the side surface of the blade and the inner peripheral surface of the cylinder when the blade swings most toward the compression chamber.

According to a third aspect of the present invention, there is provided the rotary compressor according to the first or second aspect, wherein a compression chamber is provided at the discharge port at the time of completion of compression and discharge when viewed from the axial direction. And a counterbore part which overlaps with.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a rotary compressor of a blade-integrated piston type according to the present invention, and FIG. 2 is a transverse sectional view showing its compression mechanism. 1 and 2, a compression mechanism includes a cylindrical hole 401 into which the guide 28 is rotatably fitted, a blade movement space 403 formed radially outside the cylindrical hole 401, a suction port 405, and a discharge port 301. A cylinder 4 having a cylinder chamber 402 having an opening, a piston 5 oscillating in the cylinder chamber, and an eccentric shaft 601 are rotatably fitted into the inner peripheral surface 502 of the piston 5 to revolve the piston 5. The drive shaft 6 and the cylinder 5 are provided integrally with the piston 5, and the cylinder chamber 402 is divided into a low-pressure chamber 402 b communicating with the suction port 405 and a compression chamber 402 a communicating with the discharge port 301, and the length thereof is equal to the rotation angle of the drive shaft 6. That is, a blade 501 formed such that its tip protrudes radially outward from the guide 28 at the position of the crank angle 180 °,
A guide 28 rotatably fitted into the cylindrical hole portion 401 formed in the cylinder 4 and supporting the blade 501 in a reciprocating and swingable manner, rotatably supporting the drive shaft 6, and closing the openings at both end surfaces of the cylinder chamber 402. And a cylinder head 7.

In the rotary compressor of the blade-integrated piston type configured as described above, the rotation of the drive shaft 6 causes the piston 5 to swing about the center point of the outer peripheral surface of the guide 28 via the blade 501 as a fulcrum. Revolves along the inner wall of the cylinder chamber 402, and the
A compressible fluid such as a refrigerant gas is sucked from a circuit into a cylinder chamber 402 from a suction port 405 via a suction pipe 27 attached to a cylinder 4 from a suction pipe 23 provided in the cylinder 4 and compresses the same. Has become. When the compressed fluid reaches a predetermined high pressure, it pushes up the discharge valve 25 from the discharge port 301 and is once discharged into the space between the back surface of the frame 3 and the cover 9, and passes through the discharge pipe 18 attached to the discharge plate 17. The liquid is discharged from the discharge pipe 21 provided in the closed container 1 to the circuit.

FIGS. 3 and 4 are enlarged views for explaining the position where the above-mentioned discharge port 301 is arranged. FIG. 3 shows the crank angle at which the inclination of the blade 501 becomes the largest, that is, the maximum swing angle (the crank angle). (Around 270 ° angle), Fig. 4 shows piston 5
2 shows the positional relationship at the crank angle at which the compression / discharge stroke ends, that is, at the discharge completion angle (around 360 ° crank angle).

In this embodiment, as shown in FIG. 3, the discharge port 301 is provided at a position in contact with the side surface of the blade 501 and the inner peripheral surface of the cylinder chamber 402 of the cylinder 4 at the maximum swing angle toward the compression chamber when viewed from the axial direction. Have been. That is, the discharge port 301 is provided with the blade 501 at the maximum swing angle toward the compression chamber when viewed from the axial direction.
At a position in contact with the side surface, the discharge port is provided at a position where the distance from the cylinder center to the cylinder center is a value obtained by subtracting the discharge port radius from the cylinder inner radius. By arranging the discharge port 301 at such a position, after the pressure reaches a high pressure and the discharge is started, the discharge port 301 is closed by the blade 501 in the first half of the discharge stroke where the flow rate is large and a pressure loss is likely to occur due to the large flow rate. Can be reduced. Thereby, the overshoot loss can be suppressed and the efficiency of the compressor can be increased.

Further, as shown in FIG. 4, the discharge port 301 is provided with a counterbore 302 for enlarging the entrance of the discharge port 301 so as to include the compression chamber portion at the discharge completion angle when viewed from the axial direction. . As a result, the flow path is secured without interruption of communication between the compression chamber and the discharge port near the discharge completion angle,
It is also possible to avoid invalid compression and oil compression of gas,
Noise of the compressor can be reduced. The shape of the counterbore portion 302 may be any shape that includes the inlet opening of the discharge port 301 and expands the inlet of the discharge port 301 so as to include the compression chamber portion at the discharge completion angle.

Embodiment 2 5 and 6 are enlarged views for explaining an arrangement position of the discharge ports 301 in another embodiment. As in FIG. 3, FIG. 5 shows the maximum swing angle (crank angle) at which the inclination of the blade 501 becomes the largest. FIG. 6 is a diagram corresponding to FIG. 4 showing a positional relationship at a discharge completion angle (around a crank angle of 360 °) at which the compression / discharge stroke by the piston 5 ends.

In this embodiment, as shown in FIG. 5, the discharge port 301 is in contact with the side surface of the blade 501 at the maximum swing angle toward the compression chamber side when viewed from the axial direction, and the center thereof is the cylinder chamber 40 of the cylinder 4.
2 Provided at a position on the inner peripheral surface. That is, the discharge port 30
Reference numeral 1 denotes a position in contact with the side surface of the blade 501 at the maximum swing angle toward the compression chamber when viewed from the axial direction, and is provided at a position where the distance from the center of the discharge port to the center of the cylinder becomes the cylinder radius. Further, as shown in FIG. 6, the discharge port 301 is provided with a counterbore portion 302 for enlarging the entrance of the discharge port 301 so as to include the compression chamber portion at the discharge completion angle when viewed from the axial direction. The shape of the counterbore portion 302 may be any shape that includes the inlet opening of the discharge port 301 and expands the inlet of the discharge port 301 so as to include the compression chamber portion at the discharge completion angle.

By arranging the discharge port 301 at such a position, it is possible to prevent the discharge port 301 from being closed by the blade 501 in the first half of the discharge stroke and reducing the flow path area.
3 and FIG. Since the discharge port 301 is located near the outer periphery of the cylinder 4, the discharge port diameter must be increased by an amount corresponding to the closing of the discharge port 301 by the cylinder 4 and the guide 28, but invalid compression of gas and oil compression are avoided by that much. The counterbore portion 302 for use can be made smaller.

In the above embodiment, the case where the discharge port and the counterbore portion are provided on the frame 3 side has been described.
The same applies to the case where the discharge port and the counterbore are provided on the cylinder head 7 side, or the discharge port and the counterbore are provided on both the frame 3 side and the cylinder head 7 side. When provided on the cylinder head 7 side and on both sides, a discharge path corresponding to that is naturally formed. In particular, when both are provided, the effect of suppressing the overshoot loss is great.

In the first and second embodiments, the position of the discharge port 301 is set such that the discharge port 301 contacts the side surface of the blade 501 at the maximum swing angle toward the compression chamber when viewed from the axial direction, A position where the distance from the center is a value obtained by subtracting the discharge port radius from the cylinder inner radius;
1 is in contact with the side surface of the blade 501 at the maximum swing angle to the compression chamber side when viewed from the axial direction, and the distance from the center of the discharge port to the center of the cylinder is provided at a position corresponding to the radius inside the cylinder.
The distance between the center of the discharge port and the center of the cylinder may be set between them, and the same operation and effect can be obtained.

[0024]

According to the first aspect of the present invention, there is provided a rotary compressor having a blade-integrated piston type, comprising: a rotary compressor having a blade provided integrally with a piston.
The discharge port is in contact with the blade side when it is most swung toward the compression chamber when viewed from the axial direction of the frame or cylinder head, and the distance of the discharge port center from the cylinder center is calculated by subtracting the discharge port radius from the cylinder inner radius. Is provided at at least one of the frame and the cylinder head at a position where the pressure is equal to or larger than the inner radius of the cylinder, so that the discharge port is not blocked by the blade and the discharge pressure with a large discharge flow rate An increase in discharge resistance immediately after the arrival can be suppressed, and a highly efficient rotary compressor with little overshoot loss can be obtained.

According to a second aspect of the present invention, there is provided a rotary compressor having a blade integrally provided with a piston, wherein the discharge port is viewed from an axial direction of a frame or a cylinder head. At the position in contact with the side surface of the blade and the inner peripheral surface of the cylinder when it is most swung to the compression chamber side, so that at least one of the frame and the cylinder head is provided, so that the discharge port is not blocked by the blade, A discharge port having a diameter as small as possible can suppress an increase in discharge resistance immediately after reaching a discharge pressure with a large discharge flow rate, and can provide a highly efficient rotary compressor with little overshoot loss.

According to a third aspect of the present invention, there is provided the rotary compressor according to the first or second aspect, wherein a compression chamber is provided at the discharge port when the compression / discharge is completed as viewed from the axial direction. And a counterbore part that overlaps with
In addition to the effects of claim 1 or claim 2, oil compression or the like near the discharge completion angle is suppressed, and a rotary compressor with high efficiency and low noise can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a blade-integrated piston type rotary compressor according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a compression mechanism of the blade-integrated piston type rotary compressor according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a state near a maximum swing angle near a discharge port according to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a state near a discharge completion angle near a discharge port according to the first embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a state near a maximum swing angle near a discharge port according to a second embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a state near a discharge completion angle near a discharge port according to a second embodiment of the present invention.

FIG. 7 is a cross-sectional view showing the vicinity of a discharge port of a conventional rotary compressor of a blade-integrated piston type.

FIG. 8 is a longitudinal sectional view showing the vicinity of a discharge port of a conventional rotary compressor of a blade-integrated piston type.

FIG. 9 is a longitudinal sectional view showing a conventional blade-integrated piston type rotary compressor.

FIG. 10 is a schematic diagram showing a pressure change with respect to a volume in the rotary compressor.

[Explanation of symbols]

1 closed container, 3 frames, 4 cylinders, 5 pistons, 6 drive shafts, 7 cylinder heads, 28 guides, 301
Discharge port, 302 counterbore, 401 cylindrical hole, 402 cylinder chamber, 402a compression chamber, 402b low pressure chamber, 403 blade movement space, 405 suction port, 501 blade.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Yoshihide Ogawa 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Inside Mitsubishi Electric Corporation (72) Eiji Watanabe 2-3-2 Marunouchi, Chiyoda-ku, Tokyo (72) Inventor Munehisa Korishima 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric Corporation (72) Inventor Masao Tani 2-3-2 Marunouchi, Chiyoda-ku, Tokyo (72) Inventor Minoru Ishii 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric Co., Ltd.

Claims (3)

[Claims] 1. A cylinder having a cylinder chamber and a blade movement space in which a suction port and a discharge port are opened, a piston eccentrically oscillating and revolving in the cylinder chamber, and a cylinder provided integrally with the piston. The blade is divided into a compression chamber and a low-pressure chamber, and reciprocates and swings in the blade movement space. A cylindrical hole formed between the cylinder chamber and the blade movement space of the cylinder is rotatable. A guide inserted into the piston to reciprocate and swingably support the blade; a drive shaft inserted into the inner peripheral surface of the piston to revolve the piston; and a drive shaft arranged to close the openings at both end surfaces of the cylinder chamber. And a frame for rotatably supporting the drive shaft and a cylinder head are provided in a closed container, and the rotation of the drive shaft causes the piston to swing and revolve. In the rotary compressor, which compresses the fluid sucked into the cylinder chamber from the suction port and discharges the fluid from the discharge port, wherein the discharge port is located on the compression chamber side when viewed from the axial direction of the frame or the cylinder head. At a position where the distance from the center of the discharge port center to the cylinder center is equal to or more than the value obtained by subtracting the discharge port radius from the cylinder inner radius and equal to or less than the cylinder internal radius, at least the frame and A rotary compressor provided on either one of a cylinder head. 2. A cylinder having a cylinder chamber in which an intake port and a discharge port are opened and a blade movement space, a piston eccentrically oscillating in the cylinder chamber and revolving, and the cylinder provided integrally with the piston. The blade is divided into a compression chamber and a low-pressure chamber, and reciprocates and swings in the blade movement space. A cylindrical hole formed between the cylinder chamber and the blade movement space of the cylinder is rotatable. A guide inserted into the piston to reciprocate and swingably support the blade; a drive shaft inserted into the inner peripheral surface of the piston to revolve the piston; and a drive shaft arranged to close the openings at both end surfaces of the cylinder chamber. And a frame for rotatably supporting the drive shaft and a cylinder head are provided in a closed container, and the rotation of the drive shaft causes the piston to swing and revolve. In the rotary compressor, the fluid is compressed and discharged from the discharge port by compressing the fluid sucked into the cylinder chamber from the suction port, wherein the discharge port is located on the compression chamber side when viewed from the axial direction of the frame or the cylinder head. A rotary compressor provided at least in one of a frame and a cylinder head at a position in contact with a side surface of a blade and an inner peripheral surface of a cylinder when the blade is most swung. 3. The rotary compressor according to claim 1, wherein the discharge port is provided with a counterbore portion which overlaps with a compression chamber at the time of completion of compression and discharge when viewed from the axial direction. .