JPS6343587B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an elastic support device for elastically housing an electric compressor in a closed container.

[Conventional technology]

As shown in Figure 2 of Utility Model Application Publication No. 54-177487, the conventional device uses a second spring (inner spring) wound at equal pitches with a gap between the upper spring support and the tapered lower spring support. ) is screwed and fixed inside the upper spring support,
A first spring (outer spring) is screwed and fixed to the upper spring support around its outer periphery, and this first spring is wound at an even pitch with gaps, and the lower end is an open end to prevent vertical and lateral vibrations during operation. , it is absorbed by the second spring (inner spring),
The structure is such that the first spring (outer spring) collides with the lower holder to absorb vibrations that are large in the vertical direction. In addition, in addition to the second spring, the lower end of the first spring comes into contact with the tapered portion of the second spring and the lower spring support to suppress large vibrations in the lateral direction.

[Problem to be solved by the invention]

In the conventional support device configured as described above,
If the displacement due to the lateral load that acts when the compressor starts and stops is large, the inner and outer springs may be pulled and damaged, or the compressor body may hit the closed container, causing impact noise.
There were also problems such as large distortions and damage to the refrigerant piping connecting the compressor body and the closed container. If the rigidity of the outer spring is increased in order to prevent this, the impact force at the time of a collision will increase, causing problems such as generation of knocking noise and damage to the support device. Furthermore, during lateral displacement, the lower end of the outer spring gets stuck between the inner springs, causing the inner springs to be pushed up and come out of the lower spring support.

The present invention was invented in view of the above, and an object of the present invention is to provide a highly reliable elastic support device that has both an elastic support function and a stopper function.

[Means to solve the problem]

In order to achieve the above object, the present invention includes an outer spring threaded part at the lower part of the support wall protruding from the frame of an electric compressor, and a cylindrical or truncated conical inner spring insertion part at the lower part of the outer spring threaded part. An upper spring seat forming a stopper is provided protrudingly on the upper part of the mounting wall of the airtight container, and an inner spring tightly fitting part is provided above the inner spring tightly fitting part, and the inner spring has a diameter smaller than the inner diameter of the inner spring and longer than the upper stopper. A lower spring seat with a pin-shaped lower stopper is provided protrudingly, and an inner spring with a tightly wound tightly wound part is interposed between the upper stopper and the inner spring tightly fitted part to elastically support the electric compressor. , the inner diameter is larger than the inner spring outer diameter, the wire diameter is thicker than the inner spring, the rigidity against lateral loads is greater than the inner spring, the length is long, and the tightly wound outer spring is fixed to the threaded part of the upper spring seat. The free lower end of the outer spring is located on the outer periphery of the closely wound tightly fitted part of the inner spring, and the gap between the free lower end of the outer spring and the mounting wall is larger than the gap between the upper and lower stoppers. This is achieved by forming the

[Function] With the above configuration, the inner spring has a vibration-proof support function.
The tightly wound outer spring has a lateral stopper function, and in response to relatively small lateral displacements (vibrations), the inner springs are used to reduce the lateral spring constant and absorb vibrations, and when large lateral displacements (vibrations) occur, For displacement, an outer spring is used to change the effective length of the spring according to the amount of displacement, increasing the spring constant. When the stopper is activated by this outer spring, the effective length of the outer spring is from the screwed lower end to the open lower end, and the open lower end of the outer spring, which is long and has relatively low lateral rigidity, becomes the inner spring. Contact and suppress vibration. When the stopper operates, the impact and impact noise are small, and the impact load applied to the support device is also small. Further, the outer spring does not enter the gap between the inner springs, and the inner spring does not come off from the lower spring seat. Furthermore, in response to a large displacement in the lateral direction, the intermediate portion of the outer spring comes into contact with the upper end of the lower stopper, reducing the effective spring length and suppressing the lateral displacement while increasing the lateral spring constant.

〔Example〕

An embodiment of the present invention will be described based on the drawings.
Figures 1 and 2 show the overall structure of a hermetic electric compressor. Inside a hermetically sealed container 1, there are a plurality of electric compressors 2 (three in the figure) each having a compression element at the bottom and an electric element at the top. ) is elastically housed via a support device 3. Further, although not shown, a pipe for guiding working gas is connected between the compression element and the closed container. A plurality of the support devices 3 are disposed between a support wall 2' projecting laterally from the frame of the compressor and a mounting wall 1' formed at the bottom of the closed container 1. Figure 3 shows details of the support device;
An inner spring 6 and an outer spring 7 are arranged between an upper spring seat 4 fixed to the lower surface of the support wall 2' and a lower spring seat 5 fixed to the upper part of the mounting wall 1' formed at the bottom of the closed container 1. The electric compressor 2 is elastically supported within the closed container 1. The upper spring seat 4 has a threaded part 4a on its upper part for screwing and fixing the outer spring 7, and an upper stopper 4b is formed at the lower part of the threaded part 4a for inserting and positioning the inner spring 6, and its shape is as follows. The inner spring 6 is shaped like a conical trapezoid so that the spring can be easily inserted and the inner spring 6 can be easily displaced laterally. The lower spring seat 5 is
The inner spring is fixed by inserting the lower part of the inner spring 6 into the upper part of the fixing part 5a, which has a cylindrical shape with an outer diameter that changes in three steps and has a smaller diameter toward the top, and has approximately the same diameter as the outer diameter of the inner spring 6. A fixed fitting part 5b is formed, and a pin-shaped lower stopper 5c having a smaller diameter and longer length than the inner diameter of the inner spring is protruded from the upper part of the fixed fitting part 5b. The tightly wound portion of the lower part of the inner spring 6 is tightly fitted into the inner spring tight fitting portion 5b of the lower spring seat 5, and the upper end of the spring 6 is inserted into the upper stopper 4b to elastically support the electric compressor 2. A tightly wound outer spring 7 is screwed onto the threaded part 4a of the upper spring seat 4, and the lower end of this outer spring 7 is an open end, and is located at a height opposite to the outer periphery of the tightly wound tightly fitted part of the inner spring. are doing. Further, the length of the lower stopper 5c is longer than the upper stopper 4b, and the tip surface of the lower stopper enters into the middle position of the outer spring 7, and from the lower end of the outer spring 7 to the position opposite to the tip surface of the lower stopper 5b. The outer spring length l ₁ is set to be longer than approximately the same length as the inner winding diameter of the outer spring 7 .

In addition, the spring constant of the inner spring 6 with respect to lateral displacement is
A spring considerably lower than the outer spring 7 is used. The inner spring 6 and the outer spring 7 have an appropriate winding diameter difference, an appropriate gap is formed in the radial direction between both springs 6 and 7, and a lower end of the outer spring and a mounting wall are formed between the upper and lower stoppers 4b and 5c. A gap narrower than the gap 1' is formed.
The upper spring seat 4 is laterally displaced as shown in FIGS. 4 and 5 due to a lateral load acting on the upper part of the support device 3 when the electric compressor 2 is started and stopped and during transportation. FIG. 4 shows the initial stage of lateral displacement, and FIG. 5 shows its final state. In the initial displacement shown in FIG. 4, only the inner spring 6 is displaced laterally. The inner spring 6 is connected to the inner spring tight fitting part 5
It is continuously displaced from the top of b to the top tip.
The spring constant in the lateral direction is small, and it exhibits large displacements with small loads. If this is expressed in terms of the relationship between displacement and load, it will be in the state between AB in FIG. 6, where a small load causes a large displacement, absorbs the load, and reaches point B. The state of this point B is shown in FIG. The vicinity of the center of the inner spring 6 is in contact with the upper end of the lower stopper 5c, and the open lower end of the outer spring 7 is in contact with the tightly wound tightly fitted portion of the lower part of the inner spring 6. In this state, the effective length of the outer spring is from the screwed lower end to the open lower end, and the lateral rigidity of the outer spring is relatively small, and the impact force is small because the open lower end of the substitute spring comes into elastic contact. .

Both the outer spring 7 and the inner spring 6 are tightly wound at the contact portion at the lower end, so that the outer spring 7 does not enter between the lines of the inner spring 6. When the lateral displacement further increases, lateral displacement occurs between the lower end contact part of the outer spring 7 and the lower end of the threaded part 4a, so the rigidity of the outer spring increases against the lateral load, and the lateral spring The constant increases slightly. Expressing this in terms of the relationship between displacement and load, the sixth
The state will be between B and C in the figure. This section is outer spring 7
Point C represents a state in which the contact portion of the inner spring 6 moves from the lower part to the center as the load increases, and as shown in FIG. This shows a state in which the outer spring 7 is in contact with the outer spring 7 interposed therebetween. If the lateral load increases further, the outer spring 7
The displacement is suppressed by the spring length l ₂ between the contact part P facing the upper end surface 5c' of the lower stopper 5c and the lower end of the outer spring threaded part 4a, and its lateral spring constant increases greatly and suppresses lateral displacement. If this is expressed in terms of the relationship between displacement and load, it will be between CD and C in Figure 6, which can absorb a large load with a small displacement and acts as a lateral stopper. In order to increase the inclination between CD and D (reduce the displacement relative to the load), the wire diameter of the outer spring 7 may be increased, or the stopper spring length _l2 may be shortened. Since the outer spring 7 is tightly wound, the outer spring 7 reliably hits the upper end of the lower stopper 5c through the inner spring 6 due to lateral displacement, and a stable and high vibration damping effect is performed.

In this state, the inner spring 6 has almost no effect in suppressing displacement, so the taper provided on the inner spring insertion part 4b of the upper spring seat 4 makes it easier to slide, releases the load acting on the inner spring 6, and reduces the load. By reducing this, damage to the inner spring 6 is prevented.

The vibration during operation is determined by the horizontal spring constant and the vertical spring constant of the inner spring 6 in FIG. By doing so, and by using a taper or the like in the upper stopper 4b of the upper spring seat 6, a sufficient length of the non-contact portion of the inner spring 6 is ensured, thereby reducing the spring constant and reducing operational vibration. There is.

Further, the downward movement of the electric compressor during transportation is braked by contact between the lower end of the upper stopper 4b and the upper end of the lower stopper 5c.

〔Effect of the invention〕

As explained above, according to the present invention, the lateral and vertical spring constants are small for relatively small displacement vibrations during normal operation, and the vibrations during operation are reliably buffered and absorbed. In response to large vibrations, first, the effective length of the outer spring is the length from the screwed lower end to the open lower end, and the open lower end of the outer spring, which has relatively low lateral rigidity, becomes the tightly fitted part of the inner spring. Because of the contact, the impact at the time of contact is reduced, the contact noise is reduced, the impact load is reduced, and the reliability of the support device is increased.In addition, the effective length of the spring is reduced as the displacement increases, increasing the lateral rigidity. becomes larger, the spring constant increases, and it is possible to reliably buffer and absorb vibrations and suppress product displacement.

Furthermore, the lower end of the outer spring does not enter between the lines of the inner spring in response to displacement in the lateral direction, and the inner spring does not come off.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a hermetic compressor equipped with a support device showing an embodiment of the present invention, FIG. 2 is a plan view of the hermetic compressor shown in FIG. 1 viewed from below, and FIG. FIGS. 4 and 5 are enlarged sectional views showing an embodiment of the support device of the present invention, FIGS. 4 and 5 are enlarged sectional views showing the support device of FIG. It is a spring characteristic diagram with respect to lateral vibration. 1...Airtight container, 1'...Mounting wall, 2...Electric compressor,
2'...Support wall, 3...Support device, 4...Upper spring seat, 4
a...Outer spring screw fitting part, 4b...Upper stopper, 5...Lower spring seat, 5a...Fixing part, 5b...Inner spring tight fitting part, 5c
...lower stopper, 6...inner spring, 7...outer spring.

Claims (1)

[Claims] 1. A support device for a hermetic compressor that elastically supports an electric compressor within a hermetic container by providing a plurality of support devices between a support wall protruding from the frame of the electric compressor and a mounting wall of a hermetic container. At the lower part of the support wall, an outer spring threaded part and an upper spring seat in which an upper stopper is formed by a cylindrical or truncated conical inner spring insertion part are protruded from the lower part of the outer spring threaded part, and the above-mentioned mounting is carried out. Protruding from the upper part of the wall is an inner spring tight fitting part, and a lower spring seat having a pin-shaped lower stopper formed above the inner spring tight fitting part and having a smaller diameter than the inner spring inner diameter and longer than the upper stopper; An inner spring with a tightly wound tightly wound part is interposed between the upper stopper and the inner spring tightly fitted part to elastically support the electric compressor, and has an inner diameter larger than the inner spring outer diameter and a wire diameter smaller than the inner spring A tightly wound outer spring that is thicker, has greater rigidity against lateral loads than the inner spring, and has a longer length is fixed to the threaded part of the upper spring seat and placed around the outer periphery of the inner spring, and the open lower end of the outer spring is located on the outer periphery of the tightly wound tightly fitted part of the inner spring, and is formed so that the gap between the open lower end of the outer spring and the mounting wall is larger than the gap between the upper and lower stoppers. support device.