JPH02248663A - Vibration damping device of rotary compressor - Google Patents

Abstract

PURPOSE:To obtain a sufficient vibration damping effect even if the rotating frequency is changed by fixing one end part of a tension coil having arm parts extending at right angles to the winding central axis from the both end parts of the winding to the fixture of a sealed case having a compressing element part and an electric motor part contained therein, and the other end part to an inertial body. CONSTITUTION:A sealed case 2 is vibrated by the operation of a compressor, but by vibrating the inertial body 15 of a dynamic vibration reducer 14 in the opposite phase to the vibration of the sealed case 2, the vibration of the sealed case 2 is damped. A connecting part 16 is formed of a tension coil spring having initial tension and arm parts 16b, 16d. When a space is formed between windings, bending rigidity is changed and the peak width of the natural vibration of the dynamic vibration reducer 14 is widened, causing damping effect. Therefore, the peak width of the maximum damping frequency is widened, and vibration damping effect can be obtained in a wide frequency band. Notch parts 17b, 15b are provided on the top ends of the projection part 17a and protruding part 15a of a fixture 17 and the inertial body 15, respectively, whereby the natural frequency of the dynamic vibration reducer 14 can be stabilized.

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 refrigeration equipment and the like.

BACKGROUND OF THE INVENTION In recent years, compressors used in refrigeration equipment, etc. have shifted from reciprocating type to rotary type from the viewpoint of energy and space saving, and beam vibration absorbers have been used as vibration damping devices for rotary type compressors. It is used. As conventional technology, for example,
As shown in Japanese Patent Publication No. 5B-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. 7 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 with a shrink fit. Reference numeral 4 denotes a motor rotor, which is connected and fixed to the crankshaft 5 by shrink fitting. 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 1o denotes a discharge cover, which is press-fitted and fixed to the upper bearing 9. Reference numeral 11 designates a dynamic vibration absorber, which includes an inertial body 12 and a shaft-shaped connecting portion 1 with this inertial body 12 provided at an end 13a.
3, and the other end 13b of the connecting portion 13 is fixed perpendicularly to the wall surface of the sealed case 2 by resistance welding. Further, the dynamic vibration absorber 11 is a rotary compressor 1.
The maximum damping frequency generated by achieving the natural vibration of the support system of the rotary compressor 1 itself and the first-order natural vibration of the dynamic vibration absorber 11 due to the support and fixation of the rotary compressor 1 is the rotation of the rotary compressor 1. Inertial body 12 so as to almost match the frequency.
weight, shape, and length of the connecting portion 13.

Adjusting the diameter of the cross section.

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, causing a fluctuation in angular velocity during 50 revolutions of the crankshaft, and as a reaction, force is applied to the cylinder 7, etc. . Therefore, vibrations occur in the rotational direction around the axis of the crankshaft 5, and the sealed case 2 vibrates greatly. However, by adjusting the natural frequency so that the maximum damping frequency almost matches the rotational frequency of the rotary compressor 1, the inertial body 12 of the dynamic vibration absorber 11 installed in the sealed case 2 causes vibrations opposite to the vibration of the sealed case 2. By vibrating in phase, the dynamic vibration absorber 11 supplies a reaction torque to the sealed case 2 via the connection part 13 of the dynamic vibration absorber 11 at the location where it is installed in the sealed case 2, thereby damping vibrations. .

Problems to be Solved by the Invention However, in the above configuration, the peak (Q value) of the natural vibration of the dynamic vibration absorber 11 is sharp, and this occurs due to coupling with the natural vibration of the support system of the rotary compressor 1 itself. The peak of the maximum attenuation frequency (Q value) also becomes sharper. Therefore, when the maximum damping frequency and the rotational frequency of the rotary compressor 1 match, the damping effect is extremely large.
Due to variations in the natural vibration due to manufacturing variations, etc., the maximum damping frequency caused by the natural vibration of the support system of the rotary compressor 1 itself changes, and the maximum damping frequency and the rotation of the rotary compressor 1 change. When the frequency difference between the two frequencies becomes large, the vibration 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 the vibration damping effect from decreasing due to fluctuations in the rotational frequency of a rotary compressor, manufacturing variations, etc., and prevents damage to the dynamic vibration absorber due to fatigue caused by vibration or impact. It is.

Means for Solving the Problems In order to solve the above problems, a vibration damping device for a rotary compressor according to the present invention provides a vibration damping device for a rotary compressor, which has arms extending from both ends of the winding in a direction substantially perpendicular to the winding central axis. It has a connecting part made of a coil spring, a cylindrical protrusion with a notched tip that is inserted and fixed into one end of the winding of this connecting part, and an arm extending from one end of the winding of this connecting part. A fixing tool that is fixed and attached to a sealed case in which the compression element part or the compression element part and the electric motor part are fixedly housed, and a cylinder that is inserted and fixed to the other end of the winding of the connecting part and has a notched tip. It has a protrusion of the shape of a shape, and further includes an inertial body to which an arm extending from the end of the winding is fixed.

Effect: With the above-described configuration, the present invention absorbs vibrations generated during operation of a rotary compressor by causing a dynamic vibration absorber fixed to the rotary compressor main body to vibrate in an opposite phase to the vibrations of the rotary compressor. By supplying a reaction torque to the mold compressor and attenuating it, and by using a tension coil spring as the connection between the sealed case and the inertial body, vibrations and shocks at the end of the connection that is fixed to the sealed case are damped. In addition to reducing the stress caused by the deformation that occurs, the connecting part is a tension coil spring and has an initial tension, so the bending properties of the connecting part vary depending on the amount of deformation of the connecting part, and it has damping and action against vibration. By inserting and fixing the cylindrical projections provided on the fixture and the cylindrical projections provided on the inertial body at both ends of the connection part, the winding can be tightly attached even at the ends of the connection part. Stable bending rigidity of the connecting part can be obtained, and by notching the tips of the protruding part of the fixture and the protruding part of the inertial body,
The connecting part and the protruding part of the winding or the separation part from the protruding part can be fixed in a fixed position, and the connecting part and the connecting part can be fixed by fixing the arms provided at both ends of the connecting part to the fixture and the inertial body. The tool and the inertial body can be firmly fixed.

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.

1 to 7 show an embodiment of a vibration damping device for a rotary compressor according to the present invention.

In the figure, reference numeral 14 denotes a dynamic vibration absorber, which is composed of a connecting part 16 and a fixture 17, which are made of a tight tension coil spring having an initial tension of 15 degrees on an inertial body.

15a is a cylindrical protrusion provided on the inertial body 15;
5b is a notch at the tip of the protrusion 15a. 17a is a cylindrical protrusion provided on the fixture 17, and 17b is a notch at the tip of the protrusion 17a. The fixture 17 is fixed to the sealed case 2 by welding.

The protrusion 17a of the fixture 17 is press-fitted into the end 16a of the connecting portion 16, and a hook-shaped arm 16b extending from the end 16a in a direction substantially perpendicular to the winding center axis 16e is inserted and fixed with a bolt 18. Thus, it is fixed to the fixture 17.

Furthermore, the inertia body 16 is attached to the other end 16c of the connecting portion 16.
It is fixed to the fixture 17 by press-fitting the protrusion 15a and further inserting and fixing the hook-shaped arm 16d extending from the end 16c in a direction substantially perpendicular to the winding center axis 16e with the bottle 19.

1ef is a separation part between the connecting part 16 and the protruding part 17a of the fixture 17, and preg is the separating part between the connecting part 16 and the protruding part 1 of the inertial body 15.
This is the separation part from 5a. Winding center axis 16e of connecting portion 16
is perpendicular to the rotation axis 20.

In addition, the dynamic vibration reducer 14 is configured such that the maximum damping frequency caused by the coupling of the natural vibration of the support system of the rotary compressor and the natural vibration of the dynamic vibration absorber 14 almost matches the rotational frequency of the compressor 1. The shape of 16 and the weight and shape of inertial body 160 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 cylinder 7, crank shirt)
As the pressure inside the cylinder T fluctuates greatly during one rotation of the crankshaft 6a, the angular velocity of the rotation of the crankshaft 6a fluctuates, and as a reaction, a force is applied to the cylinder 7 and the like. Therefore, vibration occurs in the rotational direction around the axis of the crank shirt 6a, causing the sealed case 2 to vibrate greatly. At this time, the maximum damping frequency caused by the coupling of 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 approximately equal to the rotational frequency of the rotary compressor 1. Therefore, the inertial body 15 of the dynamic vibration absorber 14 vibrates in the opposite phase to the vibration of the sealed case 2. Therefore, a reaction torque is supplied to the sealed case 2 via the connecting portion 16 of the dynamic vibration absorber 14 and the fixture 17 fixed to the sealed case 2, thereby damping the vibration of the sealed case 2.

Furthermore, by using a tension coil spring as the connecting portion 16, the stress at the fixed end 16d for the same displacement is smaller than that of a beam made of the same material and the same wire diameter, and fatigue due to vibration and stress due to impact can be reduced. Breakage of the fixed end 1ed due to vibration or impact can be prevented, and the reliability of the dynamic vibration absorber 14 can be improved.

Moreover, by making the connecting portion 16 a tension coil spring with initial tension, the amount of deformation in the bending direction of the connecting portion 16 increases during one cycle of vibration, and when a gap occurs between the windings, the bending rigidity decreases. The bending rigidity changes during one cycle, and the peak width of the natural vibration of the dynamic vibration absorber 14 becomes wider (the Q value becomes larger), resulting in a so-called damping effect. Therefore, the peak width of the maximum damping frequency caused by the rapid formation of the natural vibration of the dynamic vibration absorber 14 and the natural vibration of the support system of the rotary compressor 1 becomes wider, and a vibration reduction effect can be obtained in a wide frequency band.

Furthermore, fixtures 17 are attached to both ends 16a and 16c of the connecting portion 16.
By inserting and fixing the protruding part 17a of the inertial body 15 and the protruding part 1f5M of the inertial body 15, the end part 16a.

16c, the windings can be brought into close contact with each other, and the connection part 1
In addition to obtaining stable bending rigidity of 6, notches 17b are provided at the tips of the protrusion 17a and the protrusion 15a.

By providing the protrusion 16b, the protrusion 17a and the protrusion 1
The separation parts 16f and 16g between the connecting part 5a and the connecting part 16 can be fixed in position, and the natural frequency of the dynamic vibration absorber 14 can be stabilized. Furthermore, the connecting portion 160 both ends 1
By fixing hook-shaped arm parts 1eb and 1ed provided on 6a and 16c to the fixture 17 and the inertial body 16 with bolts 1918, the connecting part 1e and the fixture 17 and the inertial body 16 can be firmly fixed. can.

In addition, inertia body 16. Connecting portion 16. A similar effect can be obtained by fixing the fixture 17.

Effects of the Invention As described above, the present invention provides a connecting part made of a tension coil spring having arms extending from both ends of the winding in a direction substantially perpendicular to the winding central axis, and one end of the winding of the connecting part. It has a cylindrical protruding part with a notched tip, which is inserted into and fixed to the connecting part, and further fixes an arm part extending from one end of the winding of this connecting part, and connects the compression element part or the compression element part and the electric motor part. A fixture is attached and fixed to a sealed case that is fixedly stored, and a cylindrical protrusion with a notched tip is inserted and fixed to the other end of the winding of the connecting part, and the end of the winding is By having a more extended arm and a fixed inertial body, a dynamic absorption structure is formed, which damps the vibrations that occur during operation of the rotary compressor, and the damping effect reduces vibration in a wide frequency band. As a result, even if the rotational frequency changes due to changes in the operating conditions of the rotary compressor, a sufficient vibration reduction effect can be obtained, and the dynamic vibration absorber can be prevented from being damaged due to vibration or impact. A stable vibration reduction effect can be obtained.

[Brief explanation of drawings]

Fig. 1 is a side view of a vibration damping device for a rotary compressor showing an embodiment of the present invention, Fig. 2 is a side view of a connecting part of the vibration damping device, and Fig. 3 is a fixture of the vibration damping device. side view, 4th
The figure is a front view of the fixture, Figure 6 is a side view of the inertial body of the vibration damping device, Figure 6 is a front view of the inertial body, and Figure 7 is a rotary compressor equipped with the vibration damping device. FIG. 8 is a cross-sectional view of a rotary compressor equipped with a conventional vibration damping device. 2... Sealed case, 14... Dynamic vibration absorber, 16... Inertia body, 16... Connection part,
17... Fixture. Name of agent: Patent attorney Shigetaka Awano and 1 other person
Figure 1411ffi Figure 5 Figure 6 Figure 15α Compiled diagram

Claims (1)

[Scope of Claims] A connecting part made of a tension coil spring having arms extending from both ends of the winding in a direction substantially perpendicular to the winding central axis; and a connecting part that is inserted and fixed to one end of the winding, A sealed case that has a cylindrical protrusion with a notched tip, further fixes an arm extending from one end of the winding of this connection, and securely houses the compression element or the compression element and the electric motor. a fixing device attached and fixed to the connecting portion; and an arm portion that is inserted and fixed to the other end of the winding of the connecting portion, has a cylindrical protrusion with a notched tip, and further extends from the end of the winding. A vibration damping device for a rotary compressor, which is equipped with a fixed inertial body.