JP2766700B2 - Electric hermetic rotary compressor - Google Patents

Description

The present invention relates to an electric hermetic rotary compressor.

(Prior Art) One example of a conventional electric hermetic rotary compressor is shown in FIGS. 2 and 3. FIG.

A motor 2 and a rotary compression mechanism 3 driven by the motor 2 via a crankshaft 4 are housed inside the closed casing 1.

The stator 2a of the motor 2 is fixed to the casing 1, and the rotor 2b is fixed to the upper part of the crankshaft 4.

The rotary compression mechanism 3 includes a rolling piston 6 fitted to a crank pin 5 of a crankshaft 4, a cylinder block 7 fixed to the casing 1, an upper end plate 8 for closing an upper end opening of the cylinder block 7, and a cylinder. A lower end plate 9 for closing the lower end opening of the block 7, a blade 10 which is inserted and retracted into a slot 24 formed in the cylinder block 7, and is disposed behind the blade 10 to push it. And the like.

The cylinder block 7, the upper end plate 8 and the lower end plate 9 are fastened by bolts 29 to be integrated, and the rolling piston 6 is accommodated in the cylinder chamber 12 which is limited by these.
By bringing the tip of the blade 10 into contact with the outer peripheral surface of the rolling piston 6, the suction chamber 13 is limited on one side of the blade 10 and the compression chamber 14 is limited on the other side.

The crankshaft 4 is supported by a radial bearing 8a formed on the upper end plate 8 and a radial bearing 9a formed on the lower end plate 9, respectively.

When the crankshaft 4 is driven to rotate by the motor 2, the rolling piston 6 eccentrically rotates in the direction indicated by an arrow in the cylinder chamber 12.
Gas is sucked in from 20 and the gas in the compression chamber 14 is compressed.

The compressed gas is supplied to a discharge port formed in the upper end plate 8.
After passing through 22, a discharge valve (not shown) is pushed up to enter the discharge muffler chamber 27 limited by the upper end plate 8 and the cover 26 covering the upper surface thereof, and the pulsating component is removed. Next, the motor 2 is passed through a hole (not shown) formed in the cover 26.
The pulsatile component is further removed by expanding into the first expansion chamber 28 limited below. Next, the air gap between the stator 2a and the rotor 2b and the stator 2a
The pulsation component is further removed by entering into the second expansion chamber 15 limited above the motor 2 via the gas passage 33 formed between the casing 2 and the pulsation component. It is discharged to the outside via the pipe 16.

A lubricating oil 17 is stored in a bottom portion of the casing 1 and the lubricating oil 17 is an oil pump embedded in the crankshaft 4.
The sliding surface between the crankshaft 4 and the radial bearings 8a and 9a, the sliding surface between the crankpin 5 and the rolling piston 6, the sliding surface between the rolling piston 6 and Oil is supplied to the sliding surface with the cylinder 7.

(Problems to be Solved by the Invention) In the above-described conventional electric hermetic rotary compressor, the crankshaft 4 is supported at its lower part by radial bearings 8a and 9a, and the rotor 2a of the motor 2 is cantilevered at the upper part. If the rotor 2a has a slight unbalanced weight, the upper part of the crankshaft 4 whirls as the rotation speed of the motor 2 increases, and in extreme cases, the rotor 2b comes into contact with the stator 2a and rotates. There was a problem that it became impossible.

(Means for Solving the Problems) The present invention was invented to solve the above problems, and the gist of the present invention is to provide a rotary compression mechanism inside a closed casing and a rotary compression mechanism via a crankshaft. An electric hermetic rotary compressor including a motor to be driven, wherein the crankshaft is extended beyond the motor, and its extending end is supported by a radial bearing fixed to the hermetic casing. The other end of the rotary compression mechanism is supported by a radial bearing formed on an end plate that closes a motor side end of a cylinder block of the rotary compression mechanism, and an end plate that closes a counter motor side end of the cylinder block is connected to the crankshaft. An electric hermetic rotary compressor characterized by using a thrust plate that receives only an acting thrust load. It is in.

The extension end of the crankshaft can be supported by a radial bearing fixed to the end plate of the closed casing.

(Operation) In the present invention, the extension end of the crankshaft extending beyond the motor is supported by a radial bearing fixed to a closed casing, and the other end of the crankshaft is the motor end of the cylinder block of the rotary compression mechanism. Is supported by a radial bearing formed on the end plate that closes the end plate.
The thrust load acting on the crankshaft is supported by a thrust plate composed of an end plate that closes the end of the cylinder block opposite the motor.

(Embodiment) FIG. 1 shows one embodiment of the present invention.

The crankshaft 4 extends upward beyond the motor 2, and its extending end is supported by a radial bearing 32 fixed to the upper end plate 1 a of the closed casing 1 above the motor 2, that is, on the side opposite to the compression mechanism. . The lower end of the crankshaft 4 is supported by a radial bearing 8a formed on the upper end plate 8.

The lower end plate 9 is a thrust plate that receives only a thrust load acting on the crankshaft 4.

The other configuration is the same as that of the conventional one shown in FIGS. 2 and 3, and the corresponding members are denoted by the same reference numerals and description thereof will be omitted.

Thus, since the crankshaft 4 is supported on both sides of the motor 2 by the radial bearings 32 and 8a, even if the rotor 2b of the motor 2 has a slight unbalanced weight, it does not wobble, and therefore, the motor 2 Even when the rotation speed increases, the rotor 2b does not contact the stator 2a.

Further, the support structure of the thrust bearing 32 is simplified, and the vertical height of the closed casing 1 can be reduced. Since the lower end surface of the crankshaft 4 abuts on the thrust plate composed of the lower end plate 9, the surface pressure acting on the lower end surface is reduced, so that an oil film is easily formed on the lower end surface. As a result, even if the crankshaft and the rotor 2b of the motor 2 are vibrated up and down due to the fluctuation of the differential pressure due to the phase difference between the pulsation pressure in the first expansion chamber 28 and the pulsation in the second expansion chamber 15, Noise due to collision between the lower end surface of the shaft 4 and the upper surface of the lower end plate 9 can be reduced.

Although the embodiment in which the present invention is applied to the rigid electric hermetic rotary compressor has been described above, it is needless to say that the present invention can be applied to a horizontal electric hermetic rotary compressor.

(Effects of the Invention) In the present invention, a crankshaft is extended beyond a motor, and its extending end is supported by a radial bearing fixed to a closed casing, and the other end of the crankshaft is connected to a cylinder block of a rotary compression mechanism. Since the bearing is supported by the radial bearing formed on the end plate that closes the motor side end, even if the motor rotor has an unbalanced weight, it does not swing around and contact the stator.

Since the end plate that closes the end opposite to the motor of the cylinder block is a thrust plate that receives only the thrust load acting on the crankshaft, the contact area between the lower end surface of the crankshaft and the thrust plate increases, and the contact surface pressure decreases. At the same time, an oil film is easily formed on the contact surface, so that wear of the contact surface can be prevented and noise due to collision between the crankshaft and the thrust plate can be reduced.

If the extending end of the crankshaft is supported by a radial bearing fixed to the end plate of the closed casing,
The structure for supporting the radial bearing that supports the extension end of the crankshaft is simplified, and the closed casing can be shortened.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention. 2 and 3 show an example of a conventional electric hermetic rotary compressor. FIG. 2 is a longitudinal sectional view, and FIG. 3 is a transverse sectional view taken along line IV-IV in FIG. Closed casing ... 1, rotary compression mechanism ... 3, crankshaft ... 4, motor ... 2, cylinder block ... 7, upper end plate ... 8, lower end plate ... 9, radial bearing ... 8a, , 32, mirror plate …… 1a

Claims (2)

(57) [Claims] 1. An electric hermetic rotary compressor in which a rotary compression mechanism and a motor for driving the rotary compression mechanism via a crankshaft are accommodated inside a closed casing, wherein the crankshaft is extended beyond the motor. The extending end is supported by a radial bearing fixed to the closed casing, and the other end of the crankshaft is supported by a radial bearing formed on an end plate for closing a motor-side end of a cylinder block of the rotary compression mechanism. An electric hermetic rotary compressor, wherein an end plate that closes an end opposite to the motor of the cylinder block is a thrust plate that receives only a thrust load acting on the crankshaft. 2. The electric hermetic rotary compressor according to claim 1, wherein an extension end of said crankshaft is supported by a radial bearing fixed to a head plate of said hermetic casing.