JPH11223190A - Rotary compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the capacity of a rotary compressor with the remarkably simple structure without changing the eccentric amount of a crankshaft and the size of an outer diameter of a piston by slightly shifting a suction cut-off point in the rotating direction of a rolling piston. SOLUTION: In a rotary compressor, an outer peripheral face of a rolling piston 6 accomodated in a cylinder 7 and eccentrically rotated, is slidably kept into contact with an inner peripheral face of a cylinder 7, and a point of a blade supported by the cylinder 7 in such manner that it can appear and disappear is collided with the outer peripheral face of the rolling piston. By applying this structure, a suction chamber communicated with a suction path 20 is limited at one side of this blade, and simultaneously a compression chamber 14 communicating with a discharge port 22 is limited at the other side. An opening position of the suction path 20 is slightly moved by the distance L along the rotating direction of the rolling piston 6. Whereby the suction cut-off point S is shifted along the rotating direction of the rolling piston 6 by the distance L in comparison with the conventional one to reduce the theoretical displacement amount.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rotary compressor suitable for being incorporated in an air conditioner.

[0002]

2. Description of the Related Art An example of a conventional hermetic rotary compressor is shown in FIGS. Inside the closed casing 1, a rotary compression mechanism 3 and a motor 100 for driving the rotary compression mechanism 3 via a crankshaft 4 are accommodated. motor
The stator 101 is fixed by press-fitting into the casing 1, and the rotor 102 is fixed on the upper part of the crankshaft 4.

The rotary compression mechanism 3 includes a crank shaft 4
A rolling piston 6 rotatably fitted to the crank pin 5, a cylinder block 7 fixed to the casing 1 by plug welding, an upper bearing 8 for closing an upper end opening of the cylinder block 7, and a cylinder block 7
A lower bearing 9 for closing the lower end opening of the blade, a blade 10 supported so as to be able to protrude and retract in a slot 21 formed in the cylinder block 7, and a pressing spring disposed behind the blade 10 to press the blade. Consists of 11 mag. The crank shaft 4 is supported by an upper bearing 8 and a lower bearing 9.

A rolling piston 6 is accommodated in a cylinder chamber 12 defined by a cylinder block 7, an upper bearing 8 and a lower bearing 9, and the tip of a blade 10 is brought into contact with the outer peripheral surface of the rolling piston 6 by this. The suction chamber 13 is limited on one side of the blade 10 and the compression chamber 14 is limited on the other side.

[0005] When the crankshaft 4 is driven to rotate by the motor 100, the rolling piston 6 moves into the cylinder chamber.
The eccentric rotational movement in the direction of the arrow in 12
The gas is drawn into the suction passage 20 from the suction passage 20, and the gas in the compression chamber 14 is compressed.

The compressed gas passes through a discharge port 22 formed in the upper bearing 8, pushes up a discharge valve (not shown), and is restricted by a discharge muffler chamber 27 defined by an upper surface of the upper bearing 8 and a cover 26 covering the upper surface. And the pulsating component is removed. Next, the pulsation component is further removed by entering the first expansion chamber 28 which is limited below the motor 100 through a hole (not shown) formed in the cover 26 and expanding.

Next, a second expansion chamber 15 is located above the motor 100 via an air gap between the stator 101 and the rotor 102 and a gas passage 29 formed between the stator 101 and the casing 1. By entering and expanding, the pulsating component is further removed, and then discharged to the outside via the discharge pipe 16.

A lubricating oil 17 is stored in a bottom portion of the casing 1. The lubricating oil 17 is incorporated in the crankshaft 4, pumped by a centrifugal oil pump 18, and passes through an oil supply passage 19 formed in the crankshaft 4. Oil is supplied to a sliding surface between the crank shaft 4 and the upper bearing 8 and the lower bearing 9, a sliding surface between the crank pin 5 and the rolling piston 6, a sliding surface between the rolling piston 6 and the cylinder 7, and the like.

[0009]

When the refrigerant to be charged into the air conditioner is changed from R-22 to R-410A, the capacity of the cylinder chamber 12 can be reduced if the capacity of the rotary compressor is the same. When a large number of rotary compressors having different values are serialized, the difference between the theoretical displacements for each model becomes small.

Therefore, conventionally, the amount of eccentricity of the crank pin 5 and the outer diameter of the rolling piston 6 have been reduced in order to adjust the theoretical displacement amount, so that the type of parts increases and the cost increases. Was.

[0011]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and its gist is to provide an outer peripheral surface of a rolling piston, which is accommodated in a cylinder and eccentrically rotates. The suction chamber communicates with the suction passage on one side of the blade by sliding the tip of the blade, which is slidably in contact with the inner peripheral surface of the cylinder, and which comes into and out of contact with the outer peripheral surface of the rolling piston. In addition, in the rotary compressor which limits the compression chamber communicating with the discharge port on the other side, the suction cutoff point is slightly shifted in the rotation direction of the rolling piston.

Another feature is that a suction cutoff point is formed by forming a recess in the inner peripheral surface of the cylinder over a slight distance from the opening position of the suction passage along the rotation direction of the rolling piston. It has been shifted.

Still another feature is that the suction cutoff point is shifted by moving the opening position of the suction passage by a small distance along the rotation direction of the rolling piston.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention is shown in FIG. A recess 30 is formed in the inner peripheral surface of the cylinder 7 over a distance L from the opening position of the suction passage 20 along the rotation direction of the rolling piston 6.

Thus, the suction cutoff point S is shifted by a distance L along the direction of rotation of the rolling piston 6 from that of the conventional compressor, so that the theoretical displacement of the rotary compressor is smaller than that of the conventional compressor. Other configurations and operations are the same as those of the conventional one shown in FIGS. 3 and 4, and corresponding members are denoted by the same reference numerals and description thereof will be omitted.

A second embodiment of the present invention is shown in FIG. In the second embodiment, the suction cutoff point S is shifted from the conventional one by moving the opening position of the suction passage 20 by a small distance L along the rotation direction of the rolling piston 6. Other configurations and operations are the same as those of the conventional one shown in FIGS. 3 and 4, and corresponding members are denoted by the same reference numerals and description thereof will be omitted.

[0017]

According to the present invention, since the suction cutoff point is slightly shifted in the rotation direction of the rolling piston, the rotary compressor can be constructed with a very simple structure without changing the eccentricity of the crankshaft or the outer diameter of the rolling piston. The capacity can be reduced.

If a recess is formed on the inner peripheral surface of the cylinder over a slight distance from the opening position of the suction passage along the rotation direction of the rolling piston, a recess can be formed on the inner peripheral surface of the cylinder in a simple and inexpensive manner. The suction cut-off point can be shifted only by a simple operation.

If the opening position of the suction passage is moved by a small distance along the direction of rotation of the rolling piston, the number of machining steps does not increase, so that the suction cutoff point can be shifted more inexpensively.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a rotary compressor according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of a rotary compressor according to a second embodiment of the present invention.

FIG. 3 is a longitudinal sectional view of a conventional rotary compressor.

FIG. 4 is a transverse sectional view taken along the line BB of FIG. 3;

[Explanation of symbols]

 5 Crank pin 7 Cylinder block 6 Rolling piston 10 Blade 11 Holding spring 12 Cylinder chamber 21 Slot 13 Suction chamber 20 Suction passage 14 Compression chamber 22 Discharge port 30 Recess

Claims (3)

[Claims] An outer peripheral surface of a rolling piston, which is accommodated in a cylinder and rotates eccentrically, is brought into sliding contact with an inner peripheral surface of the cylinder, and a tip of a blade supported so as to be able to protrude and retract from the cylinder is connected to an outer periphery of the rolling piston. A rotary compressor that limits the suction chamber that communicates with the suction passage on one side of the blade by contacting the blade with the surface and at the same time limits the compression chamber that communicates with the discharge port on the other side of the blade. A rotary compressor characterized by being slightly shifted in a direction. 2. The suction cutoff point is shifted by forming a recess in the inner peripheral surface of the cylinder over a slight distance from the opening position of the suction passage along the rotation direction of the rolling piston. The rotary compressor according to claim 1, wherein 3. The rotary compressor according to claim 1, wherein the suction cut-off point is shifted by moving the opening position of the suction passage by a small distance along the rotation direction of the rolling piston.