JPH05312148A - Closed compressor - Google Patents

Abstract

PURPOSE:To prevent a discharge pipe from receiving large repeated stress by providing a coil spring between a compressor unit and a closed container so that a center line runs approximately in parallel in the direction of large vibration proper to the compressor unit. CONSTITUTION:When a crank shaft 11 is rotated by a motor part 6, a piston 10 connected to a crank eccentric part 11a through a connecting rod 12, is reciprocated in a cylinder 9, and a refrigerant is compressed. A coil spring 22 is provided between a compressor unit 16 and a closed container 4 so that the center line runs approximetry in parallel to the perpendicular line in the direction where the resultant force of the reciprocating inertia force of the piston 10, the reciprocating inertia force as well as the centrifugal force of the connecting rod 12, the centrifugal force of the crank eccentric part 11a, and the centrifugal force of a balance weight 23, becomes of minimum level while a crank is rotated once. Application of large repeated stress to a discharge pipe 19 is thus prevented, while break loss of the discharge pipe 19 due to metallic fatigue is also prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reciprocating hermetic compressor used in a refrigerating machine or the like.

[0002]

2. Description of the Related Art A hermetic compressor used in a refrigerating machine has a compressor unit housed in a hermetically sealed container, which cannot be maintained or repaired.
There is a strong demand for reliable products. Above all, the problem of breakage of the discharge pipe is emphasized because it impairs the compression function which is the original function of the compressor. Generally, a reciprocating hermetic compressor employs a method of elastically supporting the compressor unit in the hermetic container with a spring and a discharge pipe in order to make it difficult to transmit the vibration of the compressor unit to the hermetic container. Therefore,
The breakage of the discharge pipe largely depends on the support system of the spring that supports the compressor unit in the closed container. As a conventional method of elastically supporting the mechanical part in a closed container with a spring, for example,
There is a hermetic compressor as shown in Japanese Utility Model Publication No. 49-18245.

An example of the conventional hermetic compressor described above will be described below with reference to the drawings.

FIG. 4 is a sectional view of a conventional hermetic compressor. In the figure, reference numeral 1 is a hermetic compressor, and a coil spring 7 is provided in a hermetic container 4 composed of an upper shell 2 and a lower shell 3 such that a mechanical section 5 is located above and a motor section 6 is located below.
It is elastically supported by. The mechanical unit 5 includes a cylinder 9 integrally formed with the block 8, a piston 10, a crankshaft 11 having a crank eccentric portion 11a, a connecting rod 12,
The bearing 13 and the like are used.

The motor unit 6 is composed of a rotor 14 and a stator 15. The rotor 14 is shrink-fitted and fixed to the crankshaft 11, and the stator 15 is fixed to the block 8.
The mechanical unit 5 and the motor unit 6 are integrated by being screwed and fixed to the compressor unit 16. Further, a spring mounting plate 18 having a stud 17 is provided at the lower end of the stator 15, and the compressor unit 16 is inserted by inserting the coil spring 7.
I support you. Further, 19 is a discharge pipe, both ends of which are fixed to the mechanical portion 5 and the closed container 4.

The operation of the hermetic compressor constructed as described above will be described below. When the mechanical portion 5 compresses the refrigerant, reciprocation of the piston 10, the connecting rod 12 and the like, unbalanced rotation of the crank eccentric portion 11a of the crankshaft 11 and the like, and vibration of the compressor unit 16 due to the compression work of the refrigerant However, since the motor portion 6 is elastically supported by the coil spring 7 at the lower end portion thereof, the vibration generated by the compressor unit 16 is attenuated by the coil spring 7 when being transmitted to the closed container 4, and the closed container is closed. It suppresses the generation of noise caused by the vibration of 4.

In addition, as the vibration exciting force of the compressor unit 16, the piston 10 and the connecting rod 12 are used.
And the like, and the crank eccentric portion 11a of the crankshaft 11.
Since the unbalanced force of rotation such as is relatively large and the original vibration mode of the compressor unit 16 is restricted by the coil spring 7, the upper portion of the mechanical unit 5 vibrates well. Therefore, vibration is smaller at the lower end of the motor unit 6, and since the compressor unit 16 is supported by the lower end of the motor unit 6 by the coil spring 7,
Since it is supported at a position where vibration is small, the mechanical part 5
It is possible to reduce the vibration transmitted to the closed container 4 as compared with the case where it is supported by the upper part such as.

[0008]

However, in the above-mentioned conventional structure, the vibration of the compressor unit may increase in the piston direction or in the direction perpendicular to the piston direction depending on the balance mode and the design specifications of the mechanical section. Therefore, in that case, the vibration of the compressor unit is great only in a certain direction, and considering the vibration mode, the vibration is particularly large in the upper mechanical section. Therefore, the discharge pipe whose one end is fixed to the mechanical portion is subjected to a large load fluctuation in the direction in which the vibration of the compressor unit is large. Therefore, a large repetitive stress is applied to the discharge pipe, and the discharge pipe is easily broken due to metal fatigue.

The present invention solves the conventional problems, and an object of the present invention is to provide a highly reliable hermetic compressor in which a large repetitive stress is not applied to the discharge pipe and the discharge pipe is not broken.

[0010]

In order to achieve this object, a hermetic compressor of the present invention is a hermetically sealed container that includes a compressor unit including a mechanical portion such as a piston, a connecting rod, a crankshaft having a crank eccentric portion, and a motor portion. Stored inside,
In the hermetic compressor having a balance weight on the crankshaft or the rotor of the motor unit, the reciprocating inertia force of the piston, the reciprocating inertia force and centrifugal force of the connecting rod, the centrifugal force of the crank eccentric portion, and the balance weight The center line is approximately parallel to the direction in which the resultant centrifugal force is perpendicular to the direction in which it is the minimum during one rotation of the crank, but in the reciprocating direction of the piston when the minimum value of the combined force is 0. A coil spring is installed between the compressor unit and the closed container.

[0011]

With the above-described structure, the present invention suppresses the amplitude of vibration by installing the coil spring so that the center line is substantially parallel to the direction in which the original vibration of the compressor unit, which depends on the static balance form, is large. Therefore, it is possible to prevent a large repetitive stress from being applied to the discharge pipe whose both ends are fixed to the compressor unit and the hermetic container, and to provide a highly reliable hermetic compressor in which the discharge pipe is unlikely to be damaged by metal fatigue. ..

[0012]

Embodiments of the hermetic compressor of the present invention will be described below with reference to the drawings. It should be noted that the same components as those of the related art are designated by the same reference numerals and detailed description thereof will be omitted.

1 and 2 show an embodiment of the hermetic compressor of the present invention. In FIGS. 1 and 2, 20 is a spring mounting plate fixed to the upper end of the stator 15, and 21
Is a spring supporting plate fixed to the lower shell 3, and 22 is a coil which elastically supports the compressor unit 16 in the hermetic container 4 by being interposed between the spring mounting plate 20 and the spring supporting plate 21. It is a spring. The coil spring 2
2 is separate from the coil spring 7 that supports the weight of the compressor unit 16, and the center line of the coil spring is substantially parallel to the reciprocating direction of the piston 10 in a plane that passes through the center of gravity of the compressor unit 16 and is parallel to the axis of the crankshaft 11. It is installed as follows.

Reference numeral 23 is a balance weight provided on the crankshaft 11 with a center of gravity that is eccentric from the center of the crankshaft 11.

FIG. 3 is a characteristic diagram showing static balance characteristics in the embodiment shown in FIGS. In FIG. 3, Fa is the reciprocal inertial force of the piston 10, the reciprocal inertial force of the connecting rod 12 and the centrifugal force, and the centrifugal force of the crank eccentric portion 11 a, and the resultant force of the Fa and the centrifugal force Fb of the balance weight 23. The mass of balance weight 23 or the eccentric distance from the center of gravity of balance weight 23 to crankshaft 11 is set so that Fa + Fb is large in the reciprocating direction of piston 10 and small in the direction perpendicular to the reciprocating direction of piston 10. I am adjusting.

The operation of the hermetic compressor constructed as described above will be described below. The crankshaft 11 is rotated by the motor portion 6, and the crank eccentric portion 11a is eccentrically rotated. Therefore, since the piston 10 connected to the crank eccentric portion 11a via the connecting rod 12 is inserted in the cylinder 9, the piston 10 reciprocates in the cylinder 9 to compress the refrigerant. At that time, since the static balance form of the compressor unit 16 is made larger in the reciprocating direction of the piston 10, when the compressor unit 16 has no restraining force, the vibration during operation is
A large vibration mode form is formed in the reciprocating direction of the piston 10 with the center of gravity of 6 as the center. Similar to the conventional example, since the compressor unit 16 is supported by the lower end portion of the motor portion 6 via the coil spring 7, the upper portion of the mechanical portion 5 vibrates well.

At this time, the coil spring 22 is installed such that the center line of the coil spring 22 is substantially parallel to the reciprocating direction of the piston 10 in a plane that passes through the center of gravity of the compressor unit 16 and is parallel to the axis of the crankshaft 11. Therefore, the vibration of the piston 10 of the compressor unit 16 in the reciprocating direction is suppressed by the coil spring 22, and the amplitude thereof becomes small. Therefore, it is possible to prevent a large repetitive stress from being applied to the discharge pipe 19 whose both ends are fixed to the compressor unit 16 and the closed container 4, and to prevent the discharge pipe 19 from being fatigued by metal.
It is possible to obtain a highly reliable hermetic compressor that is hard to break.

The transmission of vibration from the compressor unit 16 to the closed container 4 will be described. Coil spring 22
The center-line direction spring constant of is adjusted so that the amplitude of the mechanical portion 5 is reduced without largely changing the vibration mode of the compressor unit 16. Further, since the center line direction of the coil spring 22 and the vibration direction of the compressor unit 16 are substantially parallel to each other and the coil spring 22 is arranged on the plane passing through the center of gravity, the vibration occurs only in the center line direction of the coil spring 22. Since the vibration is received, the vibration damping amount is large, and the vibration transmitted from the compressor unit 16 to the closed container 4 can be suppressed to be small by the coil spring 22. Also, the coil spring 2
Since the amplitude of the mechanical portion 5 is suppressed to a small value by 2, the amount of vibration transmission from the discharge pipe 19 to the closed container 4 and the amount of vibration transmission from the coil spring 7 to the closed container 4 are smaller than in the conventional case. Therefore, from the compressor unit 16 to the closed container 4
The vibration transmitted to is almost the same as that of the conventional supporting system as a whole, and the addition of the coil spring 22 does not increase the vibration.

As described above, the hermetic compressor of this embodiment is
Piston 10, connecting rod 12, crank eccentric portion 11a
A compressor unit 16 including a mechanical portion 5 such as a crankshaft 11 having a motor and a motor portion 6 is housed in a hermetically sealed container 4, and a balance weight 23 is provided on the crankshaft 11 or the rotor 14 of the motor portion 6. In the compressor 1, the reciprocal inertial force of the piston 10, the reciprocal inertial force of the connecting rod 12, and the centrifugal force, the centrifugal force of the crank eccentric portion 11a, and the centrifugal force of the balance weight 23 are the minimum in one revolution of the crank. Direction perpendicular to the direction where, but if the minimum resultant force is 0, piston 1
Since the coil spring 22 is installed between the compressor unit 16 and the closed container 4 such that the center line thereof is substantially parallel to the reciprocating direction of 0, a large repetitive stress is applied to the discharge pipe 19. Therefore, it is possible to obtain a highly reliable hermetic compressor in which the discharge pipe 19 is less likely to be damaged by metal fatigue.

In this embodiment, the static balance is increased in the reciprocating direction of the piston 10. However, by adjusting the balance weight 23, the static balance is increased in the direction perpendicular to the reciprocating direction of the piston 10. In that case, the coil spring 2 may be so arranged that its center line is substantially parallel to the direction perpendicular to the reciprocating direction of the piston 10.
By installing 2, the same effect as this embodiment can be obtained.

[0021]

As described above, according to the present invention, a compressor unit including a mechanical portion such as a piston, a connecting rod, a crank shaft having a crank eccentric portion, and a motor portion is housed in a closed container, and the crank shaft or In a hermetic compressor having a balance weight in the rotor of the motor section, the reciprocal inertial force of the piston, the reciprocal inertial force of the connecting rod and the centrifugal force, the centrifugal force of the crank eccentric part, and the resultant force of the centrifugal force of the balance weight are , The direction perpendicular to the direction that is the minimum during one rotation of the crank, but when the minimum value of the combined force is 0, the compressor unit and the hermetic seal are such that the center line is substantially parallel to the reciprocating direction of the piston. By installing a coil spring between the container and the container, avoid applying large repeated stress to the discharge pipe and avoid metal fatigue. Extraction pipe can be broken and hardly reliable hermetic compressor.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a hermetic compressor showing an embodiment of the present invention.

FIG. 2 is a plan view of a hermetic compressor showing an embodiment of the present invention.

FIG. 3 is a characteristic diagram showing static balance in FIGS. 1 and 2.

FIG. 4 is a cross-sectional view of a conventional hermetic compressor.

[Explanation of symbols]

 4 Airtight container 5 Mechanical part 6 Motor part 10 Piston 11 Crankshaft 11a Crank eccentric part 12 Connecting rod 14 Rotor 16 Compressor unit 22 Coil spring 23 Balance weight

Claims (1)

[Claims] 1. A compressor unit including a mechanical portion such as a piston, a connecting rod, a crankshaft having an eccentric crank portion, and a motor portion is housed in a hermetically sealed container, and a balance weight is provided on the crankshaft or the rotor of the motor portion. In the hermetic compressor having the reciprocal inertial force of the piston, the reciprocal inertial force of the connecting rod and the centrifugal force, the centrifugal force of the crank eccentric portion, and the centrifugal force of the balance weight, the resultant force is minimum during one revolution of the crank. A coil spring is installed between the compressor unit and the hermetic container so that the center line is substantially parallel to the direction perpendicular to the direction, but the reciprocating direction of the piston when the minimum value of the resultant force is 0. A hermetic compressor.