JPS5960096A - Delivery valve device for refrigerant compressor - Google Patents

Abstract

PURPOSE:To decrease the peak value of a pressure in a compression chamber, make the grinding work unnecessary and reduce a cost by a method wherein the surface roughness of the internal surface of a hole, into which the delivery valve is attached, is worked into the roughness of 10-50mRmax, which is more rough than the surface roughness of a conventional hole. CONSTITUTION:The internal surface of the hole, into which the delivery valve is attached, is worked so as to have the surface roughness of 10-50mumRmax, which is larger than the same of 0.3-3mumTmax of the conventional hole, and thereby reducing the adhering force of the hole and the valve due to oil and decreasing the peak value of the internal pressure Pc of the compression chamber. The diagram (a broken line shows a conventional example and a full line shows the practical example of this invention) shows the comparison of the case of the example of the surfae roughness 25mumRmax under the viscosity 90 CST of oil and the example of surface roughness 0.3mumRmax finished by the conventional work under the viscosity 90 CST of oil. As shown in the diagram, the peak value of the pressure Pc is reduced, the movement of the valve upon opening becomes smooth, the durability of the valve is improved, the grinding work becomes unnecessary and the cost may be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cylindrical discharge valve device for a refrigerant compressor, and particularly relates to a reduction in peak pressure in a compression chamber that occurs near the start of discharge.

Conventionally, this type of cylindrical discharge valve device for a refrigerant compressor has a first
It is configured as shown in the figure.

That is, when the gas compressed by the compressor (1) reaches a pressure slightly higher than the discharge pressure, the discharge valve device releases the pressure P from the discharge port (2). Due to the adhesion force N (5) due to the oil (11) between the hole (4) of the valve (3), the balance between the spring force F of the valve, and the discharge pressure Pd, the compression chamber pressure P. When it reaches a certain level, The valve (3) opens and gas is discharged.The displacement of this valve is regulated by the valve stopper (6).In order to improve the sealing performance of this discharge valve, conventionally the surface roughness of the hole has been increased. I used to do this often, but the surface roughness of the hole is, for example, 0.3 to 3μ771Rmax
If the pressure is improved to a certain degree, the adhesive force N between the hole and the valve will become even stronger, and as a result, the pressure inside the compression chamber will increase. The peak value of was increased.

The present invention has been made with this point in mind.

Compression chamber pressure P. In order to reduce the peak value of pressure P in the compression chamber, the inner surface of the hole is processed to become rougher due to the adhesive force between the hole and the valve oil. This has the effect of lowering the peak value of.

Note that if the roughness of the two surfaces is too rough, gas will leak into the compression chamber from the valve and hole seat surfaces, so it cannot be processed to be rougher than necessary.

FIG. 4 shows a comparison of pressure waveforms and valve movements between the two embodiments of the present invention and a conventional device. In this comparative example, the surface roughness is 2.
5μ7HRmax, X oil viscosity 900ST and surface roughness by conventional processing 03μm Rmax oil viscosity 90C8T
This is a comparison in the case of

In FIG. 1, the broken line represents the conventional example, and the solid line represents the product according to the present invention.

As can be seen from this example, the peak value of Po is.

3.2 [af] is reduced, the movement when opening the valve is smoother, and the durability of the valve is also improved. As a result, the compressor drive input was also reduced due to the reduction in compression work, and the effect of reducing noise during discharge was also confirmed through experiments.

Note that the appropriate surface roughness is determined by the oil α viscosity.

As described above, the present invention lowers the peak value of the pressure in the compression chamber by roughening the surface roughness of the hole by a predetermined amount, and the effect on performance is significant. Further, in processing, grinding is not required, and costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part of a discharge valve device of a refrigerant compressor. Figure 2 is a sectional view of only the cylinder in Figure 1, and Figure 3 is a cross-sectional view of the cylinder in Figure 1.
FIG. 4 is an enlarged sectional view of the main part of the figure, and a comparative characteristic diagram of the example of the present invention and the conventional example. In the figure, (1) is the compression chamber, (2) is the discharge bow), (31 is the discharge valve, (4) is the hole, and (6) is the stopper. Agent Makoto Kazuno -

Claims (1)

[Claims] A discharge port that communicates with the compression chamber, a cylindrical discharge valve that operates to open and close the discharge port by high pressure gas in the compression chamber, and a cylindrical valve stopper that restricts movement of the discharge valve.
In a discharge valve device configured with a hole in which a discharge valve is installed, the surface roughness of the inner surface of the hole in which the discharge valve is installed is 10 to 10.
A discharge valve device for a refrigerant compressor, characterized in that it is processed to 50μ@Rmax.