JP2800355B2 - Compressor discharge valve device - Google Patents

Description

The present invention relates to a discharge valve device for a compressor, and more particularly, to a discharge valve device having a noise reduction structure.

[Prior Art] In the positive displacement compressor used for refrigeration shown in FIG. 9, a discharge hole 14 communicating with the compression chamber 10 is formed through a valve plate 12 for closing a cylinder bore (compression chamber) 10. On the valve seat surface 16 located on the discharge chamber 22 side of the valve plate 12, a flexible discharge valve 18 for periodically opening and closing the opening of the discharge hole 14 is provided. Same discharge valve
Numeral 18 is provided independently for each discharge hole 14 or mounted in a form in which valve functions for opening and closing the openings of the plurality of discharge holes 14 are integrally connected. Regulated by The valve seat surface 16 is provided with a discharge valve 18
In general, it is necessary to ensure the sealing property with the head member joined to the extending surface in addition to the close contact with the head member, so that the surface roughness is generally 2-3.
It is finished to an extremely smooth state of about μmRz.

[Problems to be Solved by the Invention] Fine lubricating oil particles are mixed in the refrigerant gas flowing in the compressor, and the valve seat surface 16 is disposed in an environment where the lubricating oil particles adhere to both the discharge valve 18 and the discharge valve 18. I'm left. As described above, since the valve seat surface 16 is extremely smooth, when the discharge valve 18 is opened, the discharge valve 18 discharges mainly due to the surface tension of the lubricating oil interposed in the closed area around the opening. valve
18 is made to adhere to the valve seat surface 16 quite strongly. Therefore, the discharge valve 18 resists opening until the pressure in the compression chamber 10 overcomes the surface tension of the lubricating oil added to the predetermined valve opening pressure. Is discharged to As a result, the instantaneous pressure wave of the discharged refrigerant gas accompanied by over-compression and the shock vibration wave of the discharge valve 18 colliding with the retainer 20 induce noise, and the compression wave particularly used for vehicle air conditioning is generated. In fact, such noise has been regarded as a problem in the airplane as an impediment to the operation environment.

An object of the present invention is to provide a discharge valve device capable of effectively reducing noise.

Means for Solving the Problems In order to solve the above problems, the present invention is directed to a valve seat surface having an opening of a discharge hole connected to a compression chamber, wherein a discharge valve has an opening in a closed area around the opening. A configuration is adopted in which the outer peripheral region excluding the annular boundary region having a width of 0.5 to 1.3 mm including the edge is roughened to 10 to 30 μmRz.

The roughening of the closed area for reducing the valve opening resistance of the discharge valve is particularly effective on the tip side in the opening / closing axis direction from the moment applied to the discharge valve. Therefore, it is desirable that the width of the annular boundary area excluding the roughening is also set as small as possible on the front end side, and that the substantial roughening is performed in the outer peripheral area surrounding the annular boundary area. It is also possible to apply only to a substantially half area located on the distal side.

In forming the roughened area, the higher the surface roughness is, the higher the elevation value of the top of the rough surface with respect to the annular boundary surface is. Therefore, the elevation value is kept at about 5 μm according to the surface roughness. It is preferable to gouge the roughened area or perform preliminary processing so as to expand the annular boundary area.

[Operation] In the discharge valve device of the present invention, the outer peripheral region excluding the annular boundary region having the specific width including the opening edge of the discharge hole is roughened, which causes a reduction in the microscopic contact area. The rise in valve opening resistance due to surface tension is suppressed, and the pressure receiving area of the discharge valve is substantially enlarged by the compressed refrigerant gas entering the roughened area.

Therefore, the discharge valve operates smoothly at the predetermined valve opening pressure, and the pressure wave of the discharged refrigerant gas accompanied by overcompression and the vibration wave colliding with the retainer are skillfully attenuated. In addition, the discharge valve in a no-load state causes a minute gap between the discharge valve and the annular region due to the formation of the roughened region. And is tightly contacted with the opening edge of the discharge hole, so that the sealing property is sufficiently ensured. In addition, the influence of leakage through the minute gap during the discharge stroke is described above. It can be more effectively stopped by adjusting the gap value.

[Example] Hereinafter, an example of the present invention will be specifically described with reference to the drawings.

FIGS. 1 and 2 show the displacement type compressor illustrated in FIG. 9, in particular, a portion of the valve plate 12 having the discharge hole 14 penetrated therethrough and the valve plate 12 disposed on the valve seat surface 16 of the valve plate 12. Only the discharge valve 18 that periodically opens and closes the opening of the discharge hole 14 is shown.

Since the valve seat surface 16 is tightly connected to the discharge valve 18 and a head member that separates the discharge chamber 22 and the suction chamber (not shown) is coupled to the extending surface thereof, sufficient sealing performance is taken into consideration. The surface roughness is about 2 to 3 μm Rz, which is an extremely smooth state. The valve seat surface 16 has an annular boundary area having a width of 0.5 to 1.3 mm including the opening edge 14a in a closed area around the opening by the discharge valve 18 (an annular area indicated by a diameter D in FIG. 2). Only P is left as it is in the above-mentioned smooth state, and its outer peripheral area (depicted to slightly exceed the diameter D in the figure) Q
Has been roughened to 10 to 30 μmRz.Surface roughening can be performed by using a processing method such as shot blasting, grinding, or knurling.For example, in the case of shot blasting, it can be performed by masking unnecessary portions. .

As described above, in the present embodiment, the outer peripheral area Q of the sealing area on the valve seat surface 16 by the discharge valve 18 excluding the annular boundary area P having a width of 0.5 to 1.3 mm including the opening edge 14a is roughened. Therefore, the decrease in the microscopic contact area generated between the discharge valve 18 and the discharge valve 18 effectively lowers the surface tension of the lubricating oil interposed in the sealing area, that is, the valve opening resistance, as compared with a conventional smooth surface. Further, when the refrigerant gas pressure in the compression chamber rises to near the valve opening pressure, the compressed refrigerant gas that enters the roughened area Q from the minute gap in the annular boundary area P including the opening edge 14a causes the pressure receiving area of the discharge valve 18 to be increased. Is substantially increased, the effect of the surface tension is almost eliminated, and the discharge valve 18 operates smoothly at a predetermined valve opening pressure.

Therefore, an instantaneous pressure wave of the discharged refrigerant gas accompanied by over-compression and a collision vibration wave with the retainer are skillfully attenuated, and the noise is satisfactorily suppressed. On the contrary, the formation of the roughened area Q causes difficulty in the sealing property of the discharge valve 18, and particularly, gas leakage during the suction stroke tends to be a problem. Since it is bent by the differential pressure between the discharge chamber and the compression chamber and comes into close contact with the opening edge 14a, its sealing property is sufficiently ensured (FIG. 3). Needless to say, in order to achieve more secure intimate contact with the opening edge 14a, the width of the annular region P and the surface roughness of the roughened region Q are set to be related within a specified numerical value range. Is more effective. In addition, as the surface roughness of the roughened area Q is set to be larger, the elevation value of the top of the roughened surface with respect to the annular boundary area P (the gap formed with the discharge valve 18) becomes larger. As shown in FIGS. 4 and 5, in order to adjust the diameter to about 5 μm, which does not affect the gas leakage, the roughened area Q is previously gouged 30 according to the surface roughness, or the annular boundary area is adjusted. It can also be processed so that the P portion bulges 40.

Although the above-described roughened area Q has been described as a configuration covering the entire outer peripheral area of the annular boundary area P, the roughened area Q is set to a substantially half surface area located on the tip side in the opening / closing axis XX direction of the discharge valve 18. Even if it is localized, its roughened area Q is the discharge valve
Acting very effectively from the moment applied to 18, the valve opening resistance can be reduced accordingly. Further, the repetitive abutting force of the discharge valve 18 against the roughened area Q due to the moment is larger toward the distal end side, and this tends to reduce the surface roughness of the roughened area Q. It is desirable that the width of the excluded annular boundary area P is also set to a minimum of about 0.5 mm on the front end side h so as to secure a wider effective roughened area Q (FIG. 6).

FIG. 7 shows the measurement results of the noise level using several samples in which the surface roughness of the roughened area Q was set to about 15 μm Rz and only the width of the annular area P was different. The rotation speed of 1000 rpm and the compression ratio (discharge pressure / suction pressure) were 15/2. As can be understood from the figure, the smaller the width of the annular field area P, that is, the larger the roughened area Q is, the more effective the noise reduction is. However, when the width of the annular field area P is set to 1.3 mm or less, It was confirmed that the noise level was excellently reduced by 4 to 5 decibels and the effect tended to be saturated in comparison with the conventional apparatus having no roughened area Q (marked with △ in the figure).

FIG. 8 shows the result of measuring the relationship between the width of the annular boundary area P and the volumetric efficiency, which is the result of the measurement performed under the same sample and under the same conditions as in the case of the noise measurement. That is, in the case of this embodiment, the conventional device having no roughened area Q (（
), And an improvement of more than 3% in performance was observed in comparison with a sample in which the entire surface of the sealed area was roughened. As a reference example, the entire area of the sealed area was 30
In the sample roughened to μmRz (marked by x in the figure), an extreme decrease in performance was clearly confirmed.

[Effects of the Invention] As described in detail above, the present invention has the configuration described in the claims, so that the valve opening resistance of the lubricating oil interposed in the sealing area of the discharge valve is substantially reduced. The noise caused by the transient pressure wave of the discharged refrigerant gas with disappearance and over-compression and the shock vibration wave of the discharge valve colliding with the retainer is well attenuated, and the volume generated by the roughening of the valve seat surface The effect of the efficiency can be suppressed to a level that does not cause any problem in practical use.

[Brief description of the drawings]

FIG. 1 is a sectional view of an essential part showing one embodiment of a discharge valve device according to the present invention, FIG. 2 is an explanatory view showing a roughened area of a valve seat surface, and FIG.
FIG. 4 is a sectional view of a principal part similar to FIG. 1 showing a bent state of a discharge valve during a suction stroke, and FIGS. 4 and 5 show preliminary processing for adjusting a gap between the discharge valve and an annular boundary area. FIG. 6, FIG. 6 is an explanatory diagram showing an annular zone having an unequal width, FIG. 7 is a diagram showing the relationship between the width of the annular zone and noise, and FIG. 8 is a diagram showing the width and volumetric efficiency of the annular zone. FIG. 9 is a sectional view of a main part of a conventional discharge valve device. 10: Compression chamber, 12: Valve plate 14: Discharge hole, 14a: Opening edge 16: Valve seat surface, 18: Discharge valve P: Annular boundary area, Q: Roughened area

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naoto Kawamura 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture Inside Toyota Industries Corporation (56) References JP-A-2-218875 (JP, A) JP-A 2-130279 (JP, A) JP-A-3-96666 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F04B 39/10

Claims (1)

(57) [Claims] 1. A valve seat surface having an opening of a discharge hole connected to a compression chamber, wherein an annular boundary area having a width of 0.5 to 1.3 mm including an opening edge is included in a sealing area around the opening by the discharge valve. A discharge valve device for a compressor, wherein an outer peripheral region excluding the surface is roughened to 10 to 30 μmRz.