JPH0336156B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention provides a sealed type in which the shape of the internal discharge pipe that connects the discharge muffler of the compressor main body and the discharge side connecting pipe attached to the sealed case is improved. Regarding compressors.

[Technical background of the invention and its problems]

7 and 8 show the schematic structure of a conventionally known hermetic compressor, in which 1 is a hermetic case, and 2 is a compressor body disposed inside the hermetic case 1. As shown in FIG. The frame 3 of the compressor main body 2 is attached to support brackets 5 of the closed case 1 via a plurality of spring bodies 4. Further, a motor 6 is attached to the lower part of the frame 3 of the compressor main body 2, and a compression mechanism section 7 is attached to the upper part of the frame 3. This compression mechanism section 7 includes a cylinder 8,
It is formed by components such as a piston 9, a suction and discharge valve chamber 10, a suction muffler 11, and a discharge muffler 12. Furthermore, the discharge muffler 1
One end of an internal discharge pipe 13 is connected to 2 by means such as silver brazing. This internal discharge pipe 13
The other end is connected to a discharge side connecting pipe 14 attached to the sealed case 1 by means such as silver brazing. This discharge side connecting pipe 14 is connected, for example, to the high pressure side of the refrigeration cycle. For example, the refrigerant gas introduced into the cylinder 8 from the suction pipe 15 connected to the low pressure side of the refrigeration cycle through the suction muffler 11 and the suction valve chamber side of the suction and discharge valve chambers 10 causes the piston 9 to reciprocate. This compressed refrigerant gas is drawn from the cylinder 8 and guided to the high pressure side of the refrigeration cycle via the discharge valve chamber side in the suction and discharge valve chamber 10, the discharge muffler 12, the internal discharge pipe 13, and the discharge side connecting pipe 14. It is becoming more and more common.

By the way, in the case of the conventional structure, the internal discharge pipe 13 has a curved portion 16 having a relatively large bending radius, which is bent along the shape of the inner peripheral surface of the sealed case 1, as shown in FIGS. 9 to 11. It is formed by a combination of a plurality of straight portions 17 having a relatively large length and a plurality of curved portions 18 having a relatively small bending radius. However, in the case of the conventional structure described above, the natural frequency of the internal discharge pipe 13 is the natural frequency of the sealed case 1 (generally 2KHz to 4KHz).
Since there are a large number of them in a wider range than those in the range of 1, there is a problem that the natural frequency of the closed case 1 and the natural frequency of the internal discharge pipe 13 coincide in large numbers over a wide frequency band. Therefore, there was a problem in that vibrations generated from the compressor main body 2 during operation of the compressor were transmitted to the closed case 1 via the internal discharge pipe 13, causing the closed case 1 to vibrate and generate large noise.

Therefore, in order to reduce the noise of the compressor, measures such as inserting a spring into the internal discharge pipe 13 or holding the internal discharge pipe 13 through an elastic body have been devised to reduce the noise of the compressor while the compressor is in operation. Vibration transmitted from the main body 2 to the sealed case 1 via the internal discharge pipe 13 is damped. However, in this case, since the vibration damping effect is not sufficient, there is a problem that the noise of the compressor cannot be effectively reduced.

In addition, attempts have been made to reduce the vibration of the sealed case 1 and the compressor main body 2 by increasing the rigidity of the sealed case 1 and the compressor main body 2, but in this case, the cost increases significantly. There was a problem.

[Purpose of the invention]

This invention can reduce the number of natural frequencies of the internal discharge pipe that match the natural frequencies of the closed case, and effectively damp the vibrations transmitted from the compressor body to the closed case through the internal discharge pipe. It is an object of the present invention to provide a hermetic compressor which can suppress the generation of noise and also suppress an increase in cost.

[Summary of the invention]

The present invention provides a hermetic compressor having an internal support structure in which a compressor body housed inside a hermetic case is supported by the hermetic case via a spring body, in which a discharge muffler of the compressor body and a discharge muffler of the compressor body are connected to the hermetic case. An internal discharge pipe that connects the attached discharge side connecting pipe is formed by a straight part and a curved part, where E is the longitudinal elastic modulus (Kgf/cm ² ) of the internal discharge pipe, and I is the internal discharge pipe. The second moment of inertia of the area (cm ⁴ ), γ is the weight of the unit volume of the internal discharge pipe (Kgf/cm ³ ), A is the cross-sectional area of the internal discharge pipe (cm ² ), and g is the gravitational acceleration (≒981 cm/s). ² ), the length dimension L (cm) of the straight part of the internal discharge pipe is L<0.02 (E・I・g/γ・A) ^1/4 The radius R of the curved part of the internal discharge pipe ( cm) is set to R<0.07 (E・I・g/γ・A) ^1/4 .

[Embodiments of the invention]

1 to 6 show an embodiment of the present invention. Note that the same parts in FIGS. 1 to 6 as in FIGS. 7 to 11 are given the same reference numerals, and their explanations will be omitted. That is, the present invention provides a hermetic compressor having an internal support structure in which a compressor main body 2 housed inside a hermetic case 1 is supported by the hermetic case 1 via a spring body 4. 12 and the discharge side connecting pipe 14 attached to the sealed case 1 is formed by a plurality of straight parts 22... and a plurality of curved parts 23... where I is the longitudinal elastic modulus of the pipe 21 (Kgf/cm ² ), I is the moment of inertia of the internal discharge pipe 21 (cm ⁴ ), γ is the weight of unit volume of the internal discharge pipe 21 (Kgf/cm ³ ), and A is the When the cross-sectional area (cm ² ) of the internal discharge pipe 21 and g are the gravitational acceleration (≒981 cm/s ² ), the length l of each straight section 22 of the internal discharge pipe 21 is
(cm) L<0.02 (E・I・g/γ・A) Radius R of each curved part 23 of ^1/4 internal discharge pipe 21 (cm)
It is characterized by setting R<0.07 (E・I・g/γ・A) ^1/4 .

Therefore, in the case of the above structure, the internal discharge pipe 21 has a plurality of straight sections 22... and a plurality of curved sections 23...
Each straight section 2 of the internal discharge pipe 21 is formed by
The length dimension L (cm) of 2 is L<0.02 (E・I・g/γ・A) Radius R (cm) of each curved part 23 of the ^1/4 internal discharge pipe 21
Since R<0.07 (E・I・g/γ・A) is set to ^1/4 , 4000 Hz is generated from the individual vibration modes of all the straight parts 22 and curved parts 23 that form the internal discharge pipe 21. The following vibration modes can be removed, and the vibration transmission characteristics of the entire internal discharge pipe 21 can be improved. In addition, FIG. 6 shows the internal discharge pipe 21 and the discharge muffler 12 of the compressor main body 2.
When the silver soldered part 24 between the internal discharge pipe 21 and the discharge side connecting pipe 14 attached to the sealed case 1 is vibrated with a force F, the response of the silver soldered part 25 between the internal discharge pipe 21 and the discharge side connecting pipe 14 attached to the sealed case 1 (acceleration A ), in which the solid line characteristic curve X represents the internal discharge pipe 21 configured according to the present invention.
is used, the characteristic curve Y indicated by the dashed dot line indicates the transfer function when the internal discharge pipe 13 of the conventional configuration (shown in FIGS. 7 to 11) is used, respectively.
Furthermore, the hatched areas indicate areas where vibration is reduced. Therefore, as is clear from FIG. 6, the reduction in vibration is particularly remarkable in the 2KHz to 4KHz range, which is the general natural frequency band of the sealed case 1. Therefore, 2KHz is transmitted from the compressor body 2 to the sealed case 1 via the internal discharge pipe 21.
~4KHz vibration can be significantly reduced compared to conventional models, effectively damping the vibrations transmitted from the compressor body 2 to the sealed case 1 via the internal discharge pipe 21 and suppressing noise generation. be able to. Further, unlike in the past, there is no need to insert a spring into the internal discharge pipe 21 or to hold the internal discharge pipe 21 through an elastic body, so the number of parts can be reduced. ,
Since there is no need to particularly increase the rigidity of the sealed case 1, the compressor main body 2, etc., an increase in cost can also be suppressed. Furthermore, since the radius R (cm) of each curved portion 23 of the internal discharge pipe 21 is set to be sufficiently smaller than the radius of the inner peripheral surface of the sealed case 1,
The internal discharge pipe 21 can be designed with the radius R of all the curved parts 23 having a common dimension, and the internal discharge pipe 21 can be manufactured easily.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

[Effects of the Invention] According to the present invention, in a hermetic compressor having an internal support structure in which a compressor body housed inside a hermetic case is supported by the hermetic case via a spring body, the discharge of the compressor body is An internal discharge pipe connecting the muffler and the discharge side connecting pipe attached to the sealed case is formed by a straight part and a curved part,
is the longitudinal elastic modulus of the internal discharge pipe (Kgf/cm ² ), I is the moment of inertia of the internal discharge pipe (cm ⁴ ), γ is the weight of unit volume of the internal discharge pipe (Kgf/cm ³ ), and A is the The cross-sectional area of the internal discharge pipe (cm ² ), g is the gravitational acceleration (≒981
cm/s ² ), then the length L (cm) of the straight part of the internal discharge pipe is L<0.02 (E・I・g/γ・A) ^1/4 of the curved part of the internal discharge pipe Since the radius R (cm) is set to R<0.07 (E・I・g/γ・A) ^1/4 , it is possible to reduce the number of natural frequencies of the internal discharge pipe that match the natural frequencies of the sealed case. This makes it possible to effectively attenuate vibrations transmitted from the compressor body to the sealed case via the internal discharge pipe, suppressing noise generation, and also suppressing increases in cost.

[Brief explanation of drawings]

1 to 6 show one embodiment of the present invention, in which FIG. 1 is a cross-sectional view showing a schematic configuration of the entire hermetic compressor, FIG. 2 is a plan view showing an internal discharge pipe, and FIG. Figure 3 is the same front view, Figure 4 is the same side view, and Figure 5 is the same front view.
The figure is a side view showing the internal discharge pipe viewed from the direction of arrow A in Figure 2. Figure 6 shows vibrations transmitted from the compressor body to the sealed case via the internal discharge pipe during compressor operation. 7 to 11 show conventional examples, and FIG.
The figure is a cross-sectional view of the same, Figure 9 is a plan view showing the internal discharge pipe, Figure 10 is a front view of the same, and Figure 11 is a side view of the internal discharge pipe as seen from the direction of arrow A in Figure 9. It is a diagram. 1... sealed case, 2... compressor body, 4...
Spring body, 12...Discharge muffler, 14...Discharge side connection pipe, 21...Internal discharge pipe, 22...Straight section, 2
3...Curved section.

Claims (1)

[Scope of Claims] 1. A hermetic compressor having an internal support structure in which a compressor main body housed inside a hermetic case is supported by the hermetic case via a spring body, wherein a discharge muffler of the compressor main body and a An internal discharge pipe that connects the discharge side connecting pipe attached to the sealed case is formed by a straight part and a curved part, and E is the longitudinal elastic modulus (Kgf/cm ² ) of the internal discharge pipe, and I is the moment of inertia of the internal discharge pipe (cm ⁴ ), γ is the weight of unit volume of the internal discharge pipe (Kgf/cm ³ ), A is the cross-sectional area of the internal discharge pipe (cm ² ), and g is the gravitational acceleration ( ≒981cm/s ² ), the length dimension L (cm) of the straight part of the internal discharge pipe is L<0.02 (E・I・g/γ・A) ^1/4 The curved part of the internal discharge pipe A hermetic compressor characterized in that the radius R (cm) of is set to R<0.07 (E・I・g/γ・A) ^1/4 .