JPS59200088A - Rotary compressor - Google Patents

Abstract

PURPOSE:In a compression chamber having volume variable synchronously, to avoid vibration of piping by differing the position of delivery holes therby making the delivery pulsation irregular without increasing the manufacturing cost. CONSTITUTION:A delivery hole 48A communicating to the first chamber 28 at the inside of cylinder 2 is positioned while shifting by the angle theta in the reverse rotary direction of rotor 24 from the position symmetrical against the center line of the rotor 24 and a delivery hole 48B communicating to the second chamber 30. Consequently the starting timing of delivery of said holes 48A, 48B will be shifted and when the refrigerant gas delivered from both delivery hole is combined in an oil separation chamber (not shown), the pulsations at both delivery holes 48A, 48B are never overlapped as it is but overlapped while shifting to produce irregular pulsation of refrigerant gas. Consequently the maximum pressure variation is also reduced resulting in prevension of vibration of piping without increase of manufacturing cost.

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a rotary compressor equipped with a plurality of compression chambers whose volume changes synchronously with the rotation of a rotor, and particularly relates to an improvement in the discharge characteristics thereof. be.

Some conventional rotary compressors such as vane compressors are equipped with a plurality of compression chambers whose volumes change synchronously, and these compression chambers discharge at the same time.

For example, in a cylinder whose inner peripheral surface has an oval cross-sectional shape,
A rotor having a circular cross-sectional shape is disposed at two diametrically separated locations in close proximity to the inner peripheral surface of the cylinder,
A vane compressor in which four vanes are arranged at equal angular intervals on a rotor is used for compressing refrigerant gas in a cooling device. Conventionally, in this compressor, the same number of discharge holes are provided at axially symmetrical positions with the rotation center line of the rotor as the axis of symmetry, and refrigerant gas is simultaneously discharged from both discharge holes as the rotor rotates. It was supposed to be done. Therefore, the discharge pressure fluctuation of this compressor, that is, the discharge pulsation, is close to the discharge pulsation of a 4-cylinder reciprocating compressor.
The discharge pulsation was relatively large and sinusoidal. This relatively large and sinusoidal discharge pulsation tends to induce vibrations in the piping of the cooling system connected to the compressor, and this problem is caused by multiple pipes whose volumes change synchronously. It was common to all rotary compressors equipped with a compression chamber.

Purpose of the Invention In view of the above circumstances, the present invention aims to reduce pipe vibration by making discharge pulsation as irregular as possible without complicating the structure of the compressor or increasing manufacturing costs. This was done with the aim of avoiding the occurrence of

Structure of the Invention In order to achieve the above-mentioned object, the first invention provides a rotary compressor equipped with a plurality of compression chambers whose volume changes synchronously as the rotor rotates. The compression chamber is characterized in that at least one of the factors of the position, area, and number of the discharge holes and the opening pressure of the discharge valve provided at the outlet of the discharge hole are made different among the plurality of compression chambers. be. In addition, it would be even better if the areas of the plurality of discharge holes provided corresponding to one of the plurality of compression chambers or the opening pressures of the discharge valves provided in the discharge holes were made different from each other. Good results can be obtained, and this is a feature of the second invention.

Effects of the Invention It seems strange that in a plurality of compression chambers whose volumes change synchronously as described above, the discharge pulsation can be made irregular by varying the positions of the discharge holes, etc. This fact has been confirmed by experiments.

Moreover, the reason why such a phenomenon occurs is assumed to be as follows. In a normal compressor, gas is sucked and compressed in an extremely short time of, for example, 10 to 3' Q m sec. , m &
Yo wow. Wow, great fluidity. , □) The pressure inside the compression chamber becomes uneven. Therefore, when the valve opening pressure is kept constant, discharge does not always start at the same time in multiple discharge holes as considered in a static state (Pascal's principle), but the discharge hole position, area, 2 number, etc. By changing the amount, the gas discharge conditions can be changed. Therefore, by making the positions of the discharge holes of multiple compression chambers whose volumes change synchronously different, the discharge pulsations of the same waveform in those compression chambers overlap, and the discharge pulsation of the entire compressor becomes large and sinusoidal. This can be avoided.

In addition, if the opening pressure of the discharge valve is made different in multiple compression chambers, the discharge start timing from those compression chambers will be different, and the discharge pulsation of the entire compressor where these overlap will become irregular, causing compression. This reduces the possibility of inducing vibrations in the piping connected to the machine.

EXAMPLE Hereinafter, an example in which the present invention is applied to a refrigerant gas compressor used in an automobile as a near-conditioning device in a mold room will be described with reference to the drawings.

In FIG. 1, 2 is a cylinder, and both openings of the cylinder 2 are closed by a front side plate 4 and a rear side plate 6, respectively. A front housing 8 is provided on the front side of the front side plate 4 to form a suction chamber 10, and refrigerant gas such as Freon gas returned from the external circulation circuit is guided to the suction chamber 1° through the suction port 12. It is sucked into the cylinder 2. On the other hand, the rear housing 14 is connected to the front housing 8 while holding the cylinder 2 and both front and rear side plates 4.6 inside, and discharge chambers 16A and 16B (Fig. 2) are formed outside the cylinder 2. , and an oil separation chamber 18 is formed behind each of the rear side plays 1-6. Each of the above members is shown in Figure 2)20
are fastened together to form the housing of the entire compressor.

The cylinder 2 has an elliptical inner peripheral surface 22, and a cylindrical rotor 24 is housed inside the cylinder 2.

The outer peripheral surface 26 of the rotor 24 is an elliptical inner peripheral surface 22 of the cylinder.
The poles are located at two positions on the short axis of the cylinder (close to each other), and perform a sealing action to divide the space inside the cylinder 2 into a first chamber 28 and a second chamber 30.

Four radial vane grooves 32 are formed at equal angular intervals in the rotor 24, and a vane 34 is slidably inserted into each vane groove 32. The vane 34 is capable of sliding on the rotor inner circumferential surface 22 at its tip, and
．． Both front and rear side plates 4 and 6. Rotor 24. and four compression chambers 36A by four vanes 34.

36B, 36C and 36D are formed.

As shown in FIG. 1, the rotor 24 includes shafts 38 and 40 protruding from both end faces, which are rotatably supported by the rear side plate 6 and front side plate 4 via bearings 42, and 40 projects outside of the fluorocarbon 1-housing 8 while being sealed by a shaft sealing device 44, and can be connected to a drive source at this projecting end. That is, when the rotor 24 is rotated clockwise in FIG. 2 via this shaft 40, the volume of each compression chamber 36A increases once and then decreases.

The cylinder 2, which serves as a stationary wall surrounding the compression chambers 36A to 36A, is provided with suction holes 46A and 46B at positions that allow communication with the compression chambers 3EiA to 3EiA when the volume is in the process of increasing. The discharge holes 48A and 48. B is provided. The suction holes 46A and 4.6B are formed at axially symmetrical positions with respect to the center line of the rotor 24, but the discharge holes 48A and 48B are formed at positions asymmetrical with respect to the rotor center line. That is, both ridge holes 48A, 48B
are both formed near the position where the rotor outer circumferential surface 26 and the cylinder inner circumferential surface 22 are closest to each other;
8B and the rotor 24 from a symmetrical position with respect to the rotor center line.
It is located at a position deviated by an angle θ in the direction opposite to the direction of rotation of □). Discharge hole 4
8A (same as the discharge holes 48B), as shown in FIG.
A reed-type discharge valve 50A is provided corresponding to each of the discharge valves 50A, and the lift amount of each discharge valve 50A is regulated by a valve plate 52.

The refrigerant gas discharged from the discharge holes 48A, 48B to the discharge chambers 16A, 16B passes through the communication hole 54 formed in the reazide plate 6 to the oil separation chamber 18, as shown in FIG.
When the lubricating oil flows into the rear housing 14, the lubricating oil is separated by a filter 55 and is discharged from a discharge port 56 provided in the rear housing 14 to an external circulation circuit. Further, the lubricating oil separated from the refrigerant gas is stored in the lower part of the oil separation chamber 18.

In the compressor configured as described above, when the rotor 24 is rotated, refrigerant gas flows from the external circulation circuit to the suction port 12. The air is sucked into the compression chamber 36A through the suction chamber 10 and the suction holes 46A and 46B. Since this suction takes place over a very short period of time, a strong flow of refrigerant gas occurs within the compression chamber.

If the rotor 24 rotates further, the refrigerant gas will be compressed as the volume of the compression chambers 36A to 36A decreases, but the refrigerant gas continues to flow intensely as described above while being compressed, causing pressure to rise in each compression chamber. causing non-uniformity. Therefore, for example, in FIG. 2, the compression chamber 36B and the compression chamber 36D, which is located symmetrically with respect to the rotor center line, are arranged synchronously with the rotation of the rotor 24, that is, at the same time and from the same volume. The volume is reduced at a volume reduction rate, but the discharge start timings are different between the discharge holes 48A and 48B.
48B, the pressure inside them is equal to the pressure inside the discharge chamber 16A.
Discharge starts when the pressure in the compression chamber becomes higher than the pressure in the IJB by the opening pressure of the discharge valves 50A and 50B, but as mentioned above, the pressure in the compression chamber is uneven depending on the location. The discharge start timings of the discharge holes 48A and 48B, which are communicated with different parts, are different from each other. Therefore, when the refrigerant gas discharged from the discharge hole 48A and the discharge hole 48B is combined in the oil separation chamber 18, the pulsations in both the ridge holes 48Δ and 4.8B are not superimposed as they are, and the discharge Since the peaks of the pulsations are shifted and overlapped, the pulsation waveform of the refrigerant gas discharged from the discharge port 56 becomes irregular, and the maximum fluctuation width of the pressure also becomes small, which may induce vibrations in the piping of the external circulation circuit. It becomes less.

Furthermore, if the discharge conditions of the two compression chambers located symmetrically with respect to the rotor center line are different, the average pressure within the compression chambers will reach its peak at different times, and depending on the average pressure, the pressure will be applied to the rotor 24 via the vane 34. The peak times of the applied load torques are shifted from each other as shown in FIG. In FIG. 3, the curves indicated by the thin line and the dashed-dotted line indicate that the refrigerant gas in the compression chambers located symmetrically to the rotor 2
The load torque of the entire loaf 24, which is the sum of these, or the drive torque required to drive the rotor 24, is shown by the solid line in FIG. The maximum value is smaller than the drive torque indicated by the broken line, which indicates the case where the peak timings of the load torques from the two compression chambers coincide.

As mentioned above, the discharge pulsation becomes irregular (far from a simple sine wave), the pressure fluctuation range becomes smaller, and the drive torque fluctuation range also becomes smaller, thereby reducing the operating noise of the compressor. . Also, vibrations in the piping connected to the compressor are reduced.

In the embodiment described above, by making the positions of the discharge holes 48A and 48B different from each other in the rotor rotation direction, the discharge timing of the compression chamber, which is located symmetrically with respect to the rotor center line and whose volume is changed synchronously, can be controlled. However, a similar effect can also be obtained by making the cross-sectional area and number of one outlet hole different from the other outlet hole, as shown in FIG. In the embodiment shown in FIG. 4, one of the discharge holes 58A is the discharge hole 48 in the previous embodiment.
Although it is said to be the same as A, the cross-sectional area of the other discharge hole 58B is made smaller and the number thereof is increased to 61 holes. By doing so, the discharge start timings of the discharge hole 58A and the discharge hole 58B can be made different,
The same effects as in the embodiment described above can be obtained. I tend to
When the number of discharge holes is increased, the waveform of the discharge pulsation becomes more complex and contains more high frequency components than when the number of discharge holes is small.
This contributes to making the discharge pulsation of the entire compressor irregular and reducing the width of pressure fluctuation when the discharged refrigerant gases from 58B and 58B are combined.

Since the other parts are the same as those in the previous embodiment, corresponding parts are given the same reference numerals and detailed explanations will be omitted.

Furthermore, it is also possible to make the three discharge holes 58C among the six discharge holes 58B in the above embodiment small in cross-sectional area as shown in FIG.
Their position as shown in the figure.

By arbitrarily changing the cross-sectional area, number, etc., depending on the situation, it is possible to enjoy the effects of the present invention more effectively.

Further, as shown in FIG. 9, by making the lengths of the discharge valves 60, 62, 64 corresponding to the plurality of discharge holes 59 different from each other, the opening pressures of the discharge valves are made different, thereby making it possible to It is also possible to make the discharge pulsation waveform of the compression chamber itself irregular and different from the discharge pulsation waveform of other compression chambers. Further, similar effects can be obtained by varying the material and thickness of the discharge valve.

Furthermore, as shown in FIG. 10, by making the cross-sectional areas of the discharge holes 7o and 72 that correspond to a plurality of discharge valves 66.68 of the same size and shape different from each other, the opening timing of the discharge valves 66.68 can be shifted. A similar effect can be obtained.

In addition, in the embodiment shown in FIG. 11, one compression chamber has a discharge hole 74 and a discharge valve 76 similar to those in the other compression chamber. A discharge hole 78 and a discharge valve 80 are also added to the compression chamber, and by doing so, the discharge start timings of both compression chambers can be staggered.

In addition, although all of the above have shown examples in which the present invention is applied to a vane compressor equipped with a cylinder having an elliptical inner surface J and l', the type of the compressor is not limited to this. However, the present invention can be similarly applied to any rotary compressor equipped with a plurality of compression chambers in which compression work is performed synchronously with the rotation of the rotor; Various modifications based on the knowledge of those skilled in the art without making any changes.

It goes without saying that the invention may be practiced in modified forms.

[Brief explanation of the drawing]

FIG. 1 is a front view (IT sectional view in FIG. 2) of a vane compressor that is an embodiment of the present invention, and FIG.
It is a sectional view taken along ■-■ in the figure. FIG. 3 is a graph showing the variation of load torque in the compressor shown in FIGS. 1 and 2 in comparison with that of a conventional compressor. Fourth
This figure is a diagram corresponding to FIG. 2 in another embodiment of the present invention. FIGS. 5 to 8 are plan views showing the arrangement of discharge holes in other embodiments of the present invention. FIGS. 9 to 11 are partial views showing the arrangement of discharge valves in other embodiments of the present invention. 2 cylinders 16A, 16B: Discharge chamber 24:
Rotor 34: Vane 36A, 36B, 36C, 361): Compression chamber 46A',
46B: Suction hole 48A, 48B, 58A, 58B, 58C, 59°70
．． 72, 74, 78: Discharge hole 50A, 50B, 60, 62, 64, 66.68°76
．． 80: Discharge valve applicant Toyoda Automatic Loom Works Co., Ltd. is also one company 2 Figure ■ Kutodo Figure 5 t36 Figure +,, 4 @ 528-

Claims (2)

[Claims] (1) In a rotary compressor equipped with a plurality of compression chambers whose volume changes synchronously as the rotor rotates, the position of a discharge hole provided in a stationary wall surrounding the compression chambers. A low-pressure compressor characterized in that at least one of the factors of the number of areas and the opening pressure of the discharge valve provided at the outlet of the discharge hole is made different among the plurality of compression chambers. (2) In a rotor compressor equipped with a plurality of compression chambers whose volume changes synchronously with the rotation of the rotor, the position of the discharge hole provided in the stationary wall surrounding the compression chambers. At least one of the factors of the number of areas and the opening pressure of the discharge valve provided at the outlet of the discharge hole is made to differ among the plurality of compression chambers, and the compression chamber corresponds to at least one of the plurality of compression chambers. A rotary compressor characterized in that a plurality of discharge holes provided therein have different areas or opening pressures.