JPH0124398Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rotary compressor, in particular, a rotary compressor, which includes an electric motor in the upper part of a casing, a front head, a rear head, and a cylinder in the lower part, and a crankshaft connected to the rotor of the electric motor in the cylinder. The present invention relates to a rotary compressor in which compressor elements are each provided with a roller that fits into a pin portion of the rotary compressor.

Generally, in a rotary compressor configured as described above, when the pin portion and the roller are installed inside the cylinder chamber defined by the cylinder and each head, the axial end surface of the pin portion and each head are A clearance (for example, 0.07 to 2.5 mm) necessary for rotation of the crankshaft is provided between them, and the crankshaft is supported so as to be displaceable in the axial direction with respect to a bearing provided in each head. ing.

The weight of the crankshaft fixed to the rotor varies depending on the capacity of the compressor, but in general capacity it is 2 to 5 kg, and the pin part is constantly subjected to a downward force due to the weight of the crankshaft. is acting, and due to its own weight, the pin part descends and its lower end surface in the axial direction comes into contact with the rear head constituting the cylinder chamber, and the clearance is increased between the pin part and the front head. It will be formed as follows.

On the other hand, the stator of the electric motor is fixed to the upper part of the casing mainly by press-fitting means,
As shown in, for example, Japanese Utility Model Application Publication No. 55-140771, the stator is assembled to the casing so that the axial end face of the stator is the axial end face of the rotor fixed to the crankshaft. As if we were flush with each other,
This is done by setting the height position, but it is difficult to match these height positions accurately in assembly processing, and it is normal to assemble within a tolerance range of 0.5 to 1 mm. .

However, if a height deviation occurs between the stator and the rotor, a magnetic force will be generated in the rotor in the axial direction when the crankshaft is driven, displacing the rotor in the axial direction. be.

In particular, when the stator is displaced upward relative to the rotor, in other words, when the rotor is displaced downward relative to the stator, the magnetic force acts as a force that pulls the rotor upward, and The rotor is pulled up against the weight of the crankshaft, and this force changes due to fluctuations in the voltage acting on the stator.

Therefore, due to the force relationship between the force and the crankshaft's own weight, the crankshaft vibrates up and down by the clearance between the pin part and the front head, and as a result, the axis of the pin part The directional end surfaces alternately collide with the front head and rear head, producing a hitting sound, which is one of the sources of noise.

The present invention focuses on the fact that an axial magnetic force is generated in the rotor due to the height deviation between the stator and the rotor, displacing the rotor in the axial direction, and utilizes the magnetic force. The rotor is configured so that a downward magnetic force is always applied to the rotor in the same direction as the direction in which the weight of the crankshaft acts. This is intended to solve the problem of the above-mentioned hitting noise between the heads of the crankshaft pin section by constantly applying a downward magnetic force to the motor and the compression element. The upper end surface of the rotor in the electric motor is displaced upwardly with respect to the upper end surface of the stator, and the rotor is fixed to the casing so that a downward force due to electromagnetic force always acts on the rotor when the crankshaft is driven, and The lower end surface of the pin portion of the crankshaft in the axial direction is always brought into stable contact with the rear head, so that the crankshaft can be driven without any hammering noise.

Next, an embodiment of the rotary compressor of the present invention will be described based on the drawings.

What is shown in the drawing is a high-pressure dome type rotary compressor, which has a closed casing 1 with a cover plate 1b fixed to the upper part of the body 1a and a bottom plate 1c fixed to the lower part, an electric motor 2 in the upper part, and a compression element 3 in the lower part. Each arrangement is fixed.

The electric motor 2 consists of a stator 21 and a rotor 22, and the stator 21 is fixed to the body 1a mainly by press-fitting means, and the compression element 3 has a front head having an upper bearing sleeve 31a. 31 and a rear head 3 having a lower bearing sleeve 32a.
2 and a cylinder 33, each of the heads 3
1 and 32 and the cylinder 33, a pin portion 41 of the crankshaft 4 whose one end is fixed to the rotor 22 of the electric motor 2, and a roller 35 that fits into the pin portion 41 are provided. It's the interior decoration.

The compression element 3 is arranged in the cylinder 33.
is fixed to the body 1a mainly by press-fitting means, and the crankshaft 4, one end of which is fixed to the rotor 22, can be rotated freely by the bearing sleeves 31a, 32a provided in the heads 31, 32. The weight of the crankshaft 4 and rotor 22 is supported by the rear head 32, and in this supported state,
A clearance a is formed between the axially upper end surface of the pin portion 41 and the lower surface of the front head 31.

In the drawings, reference numeral 5 denotes a suction port in the cylinder 33 that communicates with the cylinder chamber 34, and a suction pipe 6 is connected to the suction port 5. Further, 7 is a discharge port, and a discharge valve 8 is provided, and the discharge port 7 is connected to the casing 1 through a discharge cover 9.
It is designed to be discharged inside.

Further, 10 is an external discharge pipe, 11 is an oil pickup, 12 is a terminal, and 13 is the rotor 2.
This is a balance weight fixed to the second end ring 22a.

However, in the above configuration, the assembly of the electric motor 2 and the compression element 3 to the casing 1 is as follows:
First, the compression element 3 is placed at a desired position on the body 1a.
The cylinder 33 is fixed by press-fitting means, and the crankshaft 4 to which the rotor 22 of the electric motor 2 is fixed is previously assembled to the compression element 3.

After the compression element 3 is assembled in this manner, the stator 21 of the electric motor 2 is fixed to the body 1a by press-fitting means.

The present invention provides a rotary compressor configured as described above and in which the electric motor 2 and the compression element 3 are fixed to the casing 1 as described above. The upper end surface is displaced upward with respect to the upper end surface of the stator 21, and the rotor 22 is fixed to the casing 1 so that a downward magnetic force always acts on the rotor 22 when the crankshaft 4 is driven.

The amount of displacement b by which the rotor 22 is displaced relative to the stator 21 is such that the stator 21 is displaced from the casing 1.
When assembling to the rotor 22, the deviation must be larger than the allowable deviation (usually 0.5 to 1 mm) and within a range that does not affect the motor characteristics, and if the deviation at the time of assembly is the largest. However, it is made so that a displacement a of 0.5 mm can be obtained.

However, in the above configuration, the stator 2
1, the rotor 22 and crankshaft 4 are driven and rotated by the electromagnetic force of the stator 21, and this driving rotation of the crankshaft 4 causes air to flow from the suction pipe 6 through the suction port 5 into the cylinder. The suction gas sucked into the chamber 34 is compressed by the eccentric rotation of the pin portion 41 and the roller 35, and passes from the discharge port 7 through the discharge valve 8 to the discharge cover 9.
From there, it is discharged into the casing 1, and then it is discharged to the outside from the external discharge pipe 10.

At this time, since the upper end surface of the rotor 22 is at a position higher than the upper end surface of the stator 21 by the amount of displacement b, the electromagnetic force by the stator 21 applies rotational torque to the rotor 22, and This acts as a force that pulls the rotor 22 downward.

The rotor 22, together with the crankshaft 4, is originally subjected to a downward force due to its own weight, and the pulling force due to the electromagnetic force is in the same direction as the force due to its own weight, so The pin portion 41 is stably supported while being in contact with the upper surface of the rear head 32 without moving up or down.

Moreover, since the displacement b is set to be larger than the allowable range of assembly misalignment of the stator 21 with respect to the rotor 22, even if assembly misalignment occurs, a downward force is always applied to the rotor 22. Therefore, regardless of the operating conditions, the pin portion 4
1 can be stably positioned on the side of the rear head 32, and no hitting noise will be generated during driving.

As described above, in the present invention, the electric motor 2 and the compression element 3 are arranged such that the upper end surface of the rotor 22 in the electric motor 2 is displaced upward with respect to the upper end surface of the stator 21, and when the crankshaft 4 is driven, The rotor 22
By fixing the crankshaft 4 to the casing 1 so that a downward force due to electromagnetic force is constantly applied to the crankshaft 4, vertical vibration of the crankshaft 4 can be prevented with a simple structure, and the impact of the pin part 41 with the front head 31 and rear head 32 can be prevented. The sound can be definitely eliminated.

[Brief explanation of the drawing]

The drawing is a longitudinal sectional view showing an embodiment of the compressor of the present invention. DESCRIPTION OF SYMBOLS 1... Casing, 2... Electric motor, 3... Compression element, 4... Crankshaft, 21... Stator, 22
...Rotor, 31...Front head, 32...
Rear head, 33... cylinder, 35... roller, 41... pin section.

Claims (1)

[Scope of utility model registration request] The electric motor 2 is placed in the upper part of the casing 1, and the front head 31, rear head 32, and cylinder 3 are placed in the lower part.
3, each of which has a compression element 3 disposed inside the cylinder 33 and having a roller 35 therein which fits into a pin portion 41 of a crankshaft 4 coupled to a rotor 22 of the electric motor 2. 2 and the compression element 3, the upper end surface of the rotor 22 in the electric motor 2 is displaced upward relative to the upper end surface of the stator 21, and when the crankshaft 4 is driven, an electromagnetic force is constantly applied to the rotor 22. A rotary compressor, characterized in that the rotary compressor is fixed to the casing 1 so that a downward force is applied thereto.