JPH04252891A - Rotary compressor - Google Patents

Abstract

PURPOSE:To disuse the conventional reed valve and improve the extent of compression efficiency in preventing any overcompression in a bore from occurring as well as to restrain a valve crack and a valve noise from occurring. CONSTITUTION:A circumferential opening groove 6, which opens a bearing inner surface of each boss part 35 to a discharge space 5 over the discharge angle range of a roller 34, is installed in at least either of the boss parts 35 of front and rear heads 32, 33. In addition, a discharge passage 7, whose one end is opened to a compression stroke end position of the roller 34 in a cylinder bore 30, and the other end is opened to the bearing inner surface of the boss part 35, is formed there, while an interconnecting groove 8 interconnecting an opening side to the bearing inner surface in the opening groove 6 and the boss part 35 of the discharge passage 7 in the discharge angle range of the roller 34, is installed in a driving shaft 4.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary compressor, and more particularly to a discharge structure for compressed gas refrigerant compressed within a bore of a cylinder.

0002

BACKGROUND OF THE INVENTION Conventionally, this type of rotary compressor is described in, for example, Japanese Patent Laid-Open No. 176678/1983, and
As shown in FIG. 10, a motor B is disposed inside a sealed casing A, and a compression element D is rotatably driven by a drive shaft C extending from the motor B.
The compression element D includes a cylinder E having a bore a, front and rear heads F and G having face surfaces that close the bore a, and a cylinder E disposed within the bore a, and a cylinder E having a bore a; It is composed of a roller H into which the eccentric shaft portion b of the drive shaft C is inserted. Further, each of the front and rear heads F and G has a discharge port I that opens into the bore a.
, I are formed, and each of these discharge ports I is provided with a reed valve J, J, respectively. Then, the drive shaft C is rotated by the drive of the motor B, and the roller H is eccentrically rotated within the bore a of the cylinder E by the eccentric shaft portion b of the drive shaft C, so that the gas is sucked into the bore a. When the refrigerant is compressed and the pressure in the compression chamber reaches the set pressure, each reed valve J is opened by the pressure in the compression chamber, and a discharge is formed from each discharge port I to the lower side of the motor B. He is trying to discharge compressed gas refrigerant into space K. In the figure, L indicates a muffler fitted over the front and rear heads F and G.

0003

[Problem to be solved by the invention] However, as mentioned above,
In the configuration in which each reed valve J is provided at each discharge port I, since the responsiveness of each reed valve J is poor, especially when used in a high speed rotation range, as shown in FIG. 11, the compression in the bore a is Overcompression (when the pressure in the room exceeds the specified design pressure)
(shaded area in the same figure), leading to a decrease in compression efficiency,
There have been problems in that valve sounds are generated as the reed valves J open and close, causing noise, and that the reed valves J may crack.

The present invention was made in view of the above-mentioned problems, and its purpose is to eliminate overcompression due to response delay of the reed valve by eliminating the reed valve, and to improve compression efficiency. Another object of the present invention is to provide a rotary compressor that can eliminate valve cracking and valve noise when using a reed valve.

[0005]

Means for Solving the Problems In order to achieve the above object, the present invention includes a cylinder 31 having a bore 30 and a front head 32 having a face that closes the bore 30.
and the rear head 33 and the roller 3 installed in the bore 30.
4 and a drive shaft 4 having an eccentric shaft portion 41 for driving the roller 34, a boss portion 35 of at least one of the front head 32 and the rear head 33 has a discharge angle range of the roller 34. a circumferential opening groove 6 that opens the inner surface of the bearing of the boss portion 35 to the discharge space 5; A discharge passage 7 is formed which opens at the stroke end position and whose other end opens at the inner surface of the bearing of the boss part 35.
A communication groove 8 is provided which communicates the opening side to the inner surface of the bearing in the discharge angle range of the roller 34.

[0006]

[Operation] When the contact point of the roller 34 rotated within the bore 30 of the cylinder 31 passes through the suction port and is in the initial stage of the compression stroke, the communication groove 8 provided in the drive shaft 4 connects to the boss portion 35. is rotated to a non-opening position between the opening groove 6 and the discharge passage 7 on the inner surface of the bearing, and the inside of the bore 30 is held in a closed state without communicating between the opening groove 6 and the discharge passage 7. Compression of the gas refrigerant takes place within the bore 30 . When the pressure in the compression chamber reaches the discharge angle of the roller 34 at which the set pressure is reached, the communication groove 8 is rotated to a position where the opening groove 6 and the discharge passage 7 communicate with the rotation of the drive shaft 4. , these opening grooves 6 and the discharge passage 7 are communicated with each other through the communication groove 8, and the bore 30
Discharge of the gas refrigerant compressed within the discharge space 5 is started. Further, communication between the opening groove 6 and the discharge passage 7 by the communication groove 8 is performed over a discharge angle range from the discharge angle to the completion of discharge, and when this discharge angle range is exceeded, the communication by the communication groove 8 The communication between the opening groove 6 and the discharge passage 7 is cut off, and the discharge stroke of the compression chamber is completed and the suction stroke begins. As described above, the opening groove 6 and the discharge passage 7 are provided on at least one side of the front and rear heads 32 and 33, and the communication groove 8 is provided on the drive shaft 4, without using a conventional reed valve. So, this drive shaft 4
As the communication groove 8 rotates, the opening groove 6 and the discharge passage 7 are connected to each other by the communication groove 8.
The compressed gas refrigerant compressed within the bore 30 can be discharged by communicating and disconnecting the reed valve, and the conventional reed valve can be omitted. As such, compression efficiency can be increased without overcompression occurring due to response delay, and valve cracking and valve noise can also be eliminated.

[0007]

[Embodiment] The rotary compressor shown in FIG. 1 has a motor 2 consisting of a stator 21 and a rotor 22 disposed in the upper inner part of a hermetic casing 1, and a compression element 3 on the lower side of the motor 2. The compression element 3 includes a cylinder 31 having a bore 30 therein, front and rear heads 32 and 33 having faces that close the upper and lower portions of the bore 30, and a cylinder 31 disposed within the bore 30. It is composed of a roller 34 provided therein. Further, a drive shaft 4 having an eccentric shaft portion 41 is connected to the rotor 22 of the motor 2, and the upper and lower portions of the eccentric shaft portion 41 of the drive shaft 4 are connected to the center upper and lower portions of the front and rear heads 32, 33. Bearings are supported by the protruding boss portions 35, 35, and the eccentric shaft portion 41 of the drive shaft 4 is inserted into the roller 34 in the bore 30, and the cylinder 31 is attached to the casing 1. Suction port 36 to which suction pipe 10 is connected
while the suction port 3 in the cylinder 31 is provided.
6, on the front side of the roller 34 in the rotational direction, a vane 37 which is moved forward and backward in constant contact with the roller 34 is disposed, as is clear from FIGS. 2 to 9, which will be described later. The vane 37 and the roller 3 against the inner wall surface of the bore 30
A suction chamber X and a compression chamber Y are respectively defined between the contact points of No. Gas refrigerant sucked into the suction chamber X from the suction port 36 of the cylinder 31 is compressed in the compression chamber Y.

[0008] Therefore, the discharge structure of the compressed gas refrigerant in the rotary compressor is constructed as follows. 2 and 3 show the roller 34 in the bore 30.
When the rotation angle of the vane 3 is 0 degrees, that is, the contact point of the roller 34 with the inner wall of the bore 30 is
4 and 5 show the state when the discharge of the compression chamber Y in the previous stroke is completed at the position opposite to the contact point 7, and FIGS. The state when the point is moved 90 degrees beyond the suction port 36 from the position shown in Figures 2 and 3 is shown below.
Furthermore, FIGS. 6 and 7 show the roller 3 in the bore 30.
4 is 180 degrees, that is, the contact point is moved 180 degrees from the position in FIGS. 2 and 3, and FIGS. 8 and 9 show the rotation of the roller 34 in the bore 30. When the angle is 270 degrees, that is,
2 and 3 respectively show the state when the contact point is moved 270 degrees from the state of FIGS. 2 and 3.

[0009]The front and rear heads 32
, 33 are provided with a discharge angle range (
(approximately 225 degrees to 360 degrees), each boss portion 35
Opening grooves 6, 6 in the circumferential direction are formed to open the inner surface of the bearing to the discharge space 5 formed on the lower side of the motor 2 inside the casing 1, and the axial direction of each opening groove 6 is Inside the walls of the front and rear heads 32, 33, one end of the roller 34 is located in the bore 30.
Discharge passages 7, 7 are formed which are opened at the end position of the compression stroke and whose other ends are opened on the inner surface of the bearing of each boss portion 35. Furthermore, each of the opening grooves 6 and each of the discharge passages 7 is formed on the outer peripheral portion of the boss portion 35 facing the inner surface of the bearing at the upper and lower portions of the eccentric shaft portion 41 of the drive shaft 4.
Communication grooves 8, 8, which are generally fan-shaped in plan view, are formed to communicate the opening side to the inner surface of the bearing in the discharge angle range of the roller 34 (approximately 225 degrees to 360 degrees).

Next, the operation of the above configuration will be explained. First, when the rotation angle of the roller 34 is within the range of 0 degrees (states shown in FIGS. 2 and 3) to 90 degrees (states shown in FIGS. 4 and 5),
That is, in the range where the contact point of the roller 34 with respect to the bore 30 is rotated 90 degrees from the position facing the vane 37 through the suction port 36, the compression of the compression chamber Y is at an initial stage and is in a state where the pressure is lower than the set pressure. and
When within this range, each communication groove 8 of the drive shaft 4 does not communicate with either the opening groove 6 or each discharge passage 7. Therefore, the inside of the compression chamber Y is maintained in a closed state, and the gas refrigerant is compressed within the compression chamber Y. Further, the rotation angle of the roller 34 is in the range of 90 to 180 degrees (see FIG.
7), each of the communication grooves 8 of the drive shaft 4 is located at the open position of each of the opening grooves 6 in each of the boss portions 35, Even if they communicate with each other, the closed surface of the drive shaft 4 is located in each of the discharge passages 7, so that each of the discharge passages 7 is closed.
Each opening groove 6 and each discharge passage 7 do not communicate with each other,
The inside of the compression chamber Y is maintained in a closed state, and the gas refrigerant is compressed. Then, when the pressure in the compression chamber Y reaches a discharge angle (for example, 225 degrees) at which the pressure in the compression chamber Y becomes the set pressure, as shown in FIG.
As shown in 9, as the drive shaft 4 rotates, each of the communication grooves 8 is rotated to an open position where each of the opening grooves 6 and each of the discharge passages 7 are opened, and each of the communication grooves 8 is rotated to the position where each of the opening grooves 6 and each of the discharge passages are opened. 7 are communicated with each other through the communication grooves 8, and the gas refrigerant compressed within the bore 30 is discharged into the discharge space 5. Further, communication between each of the opening grooves 6 and each discharge passage 7 through each of the communication grooves 8 is performed over a discharge angle range from discharge of the roller 34 to completion of discharge, and when this discharge angle range is exceeded, the The communication between each opening groove 6 and each discharge passage 7 through each communication groove 8 is cut off, and the discharge stroke is completed.

Therefore, the gas refrigerant compressed in the compression chamber Y can be discharged within a predetermined discharge angle range without using a reed valve as in the conventional example.
Over-compression can be eliminated and compression efficiency can be improved.

[0012] As an example, the discharge angle is set to 225 degrees at which the pressure in the compression chamber Y reaches the set pressure, but it may be designed so that the compression chamber A communicates with the pressure just before the set pressure is reached. Furthermore, it goes without saying that the discharge angle range will be changed if the set pressure changes.

In the above embodiment, the front and rear heads 32 and 33 have the opening groove 6 and the discharge passage 7, respectively.
In the present invention, the opening groove 6 and the discharge passage 7 are connected to the front and rear heads 32, 3, and 4, respectively. The communication groove 8 may be provided only on one side of the drive shaft 33, or may be formed only on one side of the drive shaft 4 in the vertical direction.

[0014]

As explained above, in the rotary compressor of the present invention, the inner surface of the bearing of the boss portion 35 is provided on the boss portion 35 of at least one of the front and rear heads 32, 33 over the discharge angle range of the roller 34. An opening groove 6 in the circumferential direction opened to the discharge space 5, located on one side of the opening groove 6 in the axial direction, one end opening at the end position of the compression stroke of the roller 34 in the cylinder bore 30, and the other end opening at the end position of the compression stroke of the roller 34 in the cylinder bore 30. A discharge passage 7 that opens to the bearing inner surface of the boss portion 35 is formed, and the opening side of the opening groove 6 and the discharge passage 7 to the bearing inner surface of the boss portion 35 is formed on the drive shaft 4, and the roller 3
Since the communication groove 8 is provided to allow communication in the discharge angle range 4, the conventional reed valve can be eliminated, and the compression chamber can be forcibly opened to the discharge space at a desired discharge angle for discharge. Like when using a valve,
Overcompression can be prevented, compression efficiency can be increased, and valve cracking and valve noise can also be eliminated.

[Brief explanation of the drawing]

FIG. 1 is a partially omitted sectional view of a rotary compressor according to the present invention.

FIG. 2 is a plan cross-sectional view of the main parts of the rotary compressor, illustrating an operating state (rotation angle of 0 degrees).

FIG. 3 is a cross-sectional view taken along line A-A in FIG.

[Figure 4] Operating state of the same rotary compressor (rotation angle 90
FIG.

FIG. 5 is a sectional view taken along line B-B in FIG.

[Figure 6] Operating state of the same rotary compressor (rotation angle 18
0 degree) is a plan sectional view of the main part.

FIG. 7 is a sectional view taken along line C-C in FIG.

[Figure 8] Operating state of the same rotary compressor (rotation angle 27
0 degree) is a plan sectional view of the main part.

9 is a sectional view taken along line D-D in FIG. 8. FIG.

FIG. 10 is a partially omitted cross-sectional view showing a conventional rotary compressor.

FIG. 11 is a diagram illustrating compression characteristics by the rotary compressor.

[Explanation of symbols]

30 Boa 31 Cylinder 32 Front head 33 Rear head 34 Roller 35 Boss part 4 Drive shaft 41　Eccentric shaft part 5 Discharge space 6 Opening groove 7 Discharge passage 8 Communication groove

Claims (1)

[Claims] 1. A cylinder 31 having a bore 30 and a front head 3 having a face that closes the bore 30.
2, a rear head 33, a roller 34 installed in the bore 30, and a drive shaft 4 having an eccentric shaft portion 41 for driving the roller 34. The boss portion 35 has a circumferential opening groove 6 that opens the bearing inner surface of the boss portion 35 to the discharge space 5 over the discharge angle range of the roller 34, and a circumferential opening groove 6 located on one side of the opening groove 6 in the axial direction. , a discharge passage 7 is formed, one end of which opens at the end position of the compression stroke of the roller 34 in the bore 30, and the other end of which opens into the inner surface of the bearing of the boss portion 35; 6 and the boss portion 3 of the discharge passage 7
5. A rotary compressor characterized in that a communication groove 8 is provided which communicates the opening side to the inner surface of the bearing in the discharge angle range of the roller 34.