JPH029989A - Vibration damping equipment for rotary compressor - Google Patents

Abstract

PURPOSE:To secure a vibration damping effect and prevent a dynamic vibration reducer from being broken down as well as to aim at stable vibration abatement by installing a coiled spring fixed to a closed case or a compressive element part at its one end and an inertial body fixed to the other end of the spring respectively. CONSTITUTION:There are provided with a coiled spring 16 fixed to a closed case 2 in which a motor part and a compressive element part are fixed and housed or this compressive element part at its one end, and an inertial body 15 fixed to the other end of this spring 16. With suchlike constitution, vibration to be generated at time of operation of a rotary compressor 1 is damped by feeding this rotary compressor 1 with reaction torque when a beam dynamic vibration reducer 14 fixed to a rotary compressor body is vibrated in opposite phase against vibration of the rotary compressor 1. Then, a connection between the closed case 2 and the inertial body 15 is formed into the coiled spring 16, whereby stress due to any deformation being produced by a vibration and an impact in an end of the spring being fixed to the closed case 2 is thus relieved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a vibration damping device for a rotary compressor used in a refrigeration system or the like.

BACKGROUND OF THE INVENTION In recent years, compressors used in refrigeration equipment, etc. have shifted from reciprocating types to rotary types from the viewpoint of energy and space saving, and beam type dynamic absorbers have been used as vibration damping devices for the rotary type compressors. It is being As for the conventional technology,
As shown in Japanese Patent No. 5486, there is a vibration damping structure for a rotary hermetic electric compressor.

Hereinafter, an example of the vibration damping structure of the conventional rotary compressor mentioned above will be explained with reference to the drawings.

FIG. 2 is a partial cross-section of a conventional rotary compressor. In the figure, 1 is a rotary compressor, and 2 is a closed case. 3 is a stator of the motor, which is fixed to the sealed case 2 by shrink fitting. 4 is the rotor of the motor, and the crankshaft 5
It is connected and fixed with a shrink fit. A piston 6 is rotatably fixed to the eccentric portion of the crankshaft 5. 7 is a cylinder with lower bearings 8 at both ends. An upper bearing 9 is provided, and the outer peripheral portion is welded and fixed to the sealed case 2. Reference numeral 10 denotes a discharge cover, which is press-fitted and fixed to the upper bearing 9. Reference numeral 11 denotes a double-beam vibration absorber, which includes an inertial body 12 and a shaft-shaped connecting portion 1 with this inertial body 12 provided at an end 13-a.
3, and is fixed perpendicularly to the wall surface of the sealed case 2 by welding the other end 13b of the connecting portion 13. Moreover, the beam vibration absorber 11 is connected to the rotary compressor 1.
The maximum damping frequency generated by achieving the natural vibration of the support system of the rotary compressor 1 itself by supporting and fixing the rotary compressor 1 and the first-order natural vibration of the beam vibration absorber 11 is the maximum damping frequency of the rotary compressor 1. Inertial body 1 so as to almost match the rotational frequency
The weight and shape of 2, the length of the connecting portion 13, and the diameter of the cross section are adjusted.

The operation of the vibration damping device for a rotary compressor configured as described above will be described below.

When compressing the refrigerant in the cylinder 7, the pressure in the cylinder 7 fluctuates greatly during one revolution of the crankshaft, which causes fluctuations in the angular velocity of the rotation of the crankshaft 5, and as a reaction, forces are exerted on the cylinder 7, etc. receive. Therefore, the rotational direction of the crankshaft 5 is captured around the axis of the crankshaft 5, and the sealed case 2 is moved to a large extent. However, the inertia body 12 of the beam vibrator 11 installed in the sealed case 2 is adjusted so that the maximum attenuation frequency almost matches the rotational frequency of the rotary compressor 1.
By vibrating in the opposite phase to the imaging of the beam vibration absorber 1
1 transfers the reaction torque to the sealed case 2 through the connection part 13 of the beam vibration absorber 11 at the location where it is installed in the sealed case 2.
It is used to dampen vibrations.

Problems to be Solved by the Invention However, in the above configuration, the beam type dynamic suction device 11
Since the peak of the natural frequency (Q value) is sharp, the peak of the maximum damping frequency (Q value) caused by the combination with the natural vibration of the support system of the rotary compression ial itself also becomes sharp. Therefore, when the maximum damping frequency and the rotational frequency of the rotary compressor 1 match, the damping effect is extremely large. The maximum damping frequency caused by the natural vibration of the support system of the rotary compressor 1 itself changes due to a change in the natural frequency due to manufacturing variations, etc. When the frequency difference from the rotational frequency becomes large, the imaging damping effect becomes insufficient.

Furthermore, stress is concentrated on the end portion 13b of the connecting portion 13 due to the deformation of the connecting portion 13, so that it may break due to fatigue caused by vibration or impact.

In view of the above-mentioned problems, the present invention prevents a decrease in the vibration damping effect due to fluctuations in the rotational frequency of the rotary compressor 1, manufacturing variations, etc. This is to prevent destruction.

Means for Solving the Problems In order to solve the above problems, the vibration damping device for a rotary compressor of the present invention has one end fixed to a closed case in which a motor part and a compression element part are fixedly housed, or to a compression element part. It includes a coil-shaped connecting portion and an inertial body fixed to the other end of the connecting portion.

Effect of the present invention With the above-described configuration, the beam vibration absorber fixed to the rotary compressor main body vibrates in a phase opposite to the vibration of the rotary compressor to absorb the vibrations generated during operation of the rotary compressor. By supplying a reaction torque to the rotary compressor, the rotary compressor is damped, and by making the connection between the hermetic case and the inertial body coil-shaped, it is possible to photograph the end of the connection that is fixed to the hermetic case. Reduces stress caused by deformation caused by motion or impact.

EXAMPLE An example of the present invention will be described below with reference to the drawings. Incidentally, in order to avoid duplication of explanation, the same parts as in the conventional example are given the same reference numerals and the explanation will be omitted.

FIG. 1 shows an embodiment of a dynamic damping device for a rotary compressor according to the present invention. In the figure, 14 is installed perpendicularly to the shaft 5, and its end 16a is fitted into and fixed to a screw 17 fixed to the sealed case 2, and the other end 16b is fixed to a screw (not shown) fixed to the inertial body 14. ) is fitted and fixed.

Furthermore, the dynamic vibration absorber 14 is designed to have a shape of the groove #1b and an inertial body so that the natural vibration frequency of the support system of the rotary compressor almost matches the transposition wave number of the natural frequency of the dynamic vibration absorber 14. The weight and shape of 15 were adjusted.

The operation of the vibration damping device for a rotary compressor configured as described above will be described below.

When compressing the refrigerant in the cylinder 7, the pressure inside the cylinder 7 fluctuates greatly during one revolution of the crankshaft 5, causing fluctuations in the angular velocity of the rotation of the crankshaft 5, and as a reaction, the pressure inside the cylinder 7 changes greatly. Receive power. Therefore, vibrations occur in the rotational direction around the axis of the crankshaft 5, and the sealed case 2 vibrates greatly. At this time, the maximum damping frequency generated by achieving the natural vibration of the dynamic vibration absorber 14 installed in the sealed case 2 and the natural vibration of the support system of the rotary compressor 1 itself is set to approximately match the rotational frequency of the rotary compressor 1. Since the inertial body 15 of the dynamic vibration absorber 14 is rubbed by the closed case, a damping effect is obtained, and the width of the peak of the natural frequency of the dynamic vibration absorber 14 becomes wider (the Q value becomes larger). . Therefore, the width of the peak of the maximum damping frequency caused by achieving the natural vibration of the dynamic vibration reducer 14 and the natural vibration of the support system of the rotary compressor 1 becomes wider (because the Q value becomes thicker, it can be applied to a wider frequency band). A vibration damping effect can be obtained, and changes in the rotational frequency due to changes in the operating conditions of the rotary compressor 1 and changes in the maximum damping frequency caused by variations in the natural frequency during mass production of beam-type dynamic absorbers can be avoided. A sufficient vibration damping effect can be obtained.

Also, the screw 17 is made by making the crystal 16 into a coil shape.
The reliability of the dynamic vibration absorber 14 can be improved by hermetically sealing the reaction torque. Note that the same effect can be obtained by similarly fixing the end portion 16a of the crystal 16 to the compression element portion instead of the closed case 2.

Effects of the Invention As described above, the present invention provides a sealed case in which a motor section and a compression element section are fixedly housed, or a coil-shaped connection section having one end fixed to the compression element section, and a coil-shaped connection section at the other end of the connection section. By equipping the rotary compressor with a fixed inertial body, it damps the vibration that occurs during operation of the rotary compressor, and gives a damping effect to the dynamic vibration absorber, which can be used to prevent changes in the operating conditions of the rotary compressor or during manufacturing. A sufficient perturbation damping effect can be obtained even if there are variations in the dynamic vibration absorber, and furthermore, it is possible to prevent the dynamic vibration absorber from being destroyed due to vibration or impact, and stable vibration reduction of the rotary compressor can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a vibration damping device for a rotary compressor showing an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional vibration damping device for a rotary compressor. Figure 1? -Closing case 16- Spring

Claims (1)

[Claims] A rotary compression device comprising a sealed case that fixedly houses an electric motor section and a compression element section, or a coil-shaped connection section that has one end fixed to the compression element section, and an inertial body fixed to the other end of this connection section. Machine vibration damping device.