Suction Valve For Rotary Compressor

Abstract

A rotary compressor comprising a cylindrical wall member and an end plate forming a compression chamber has a channel in one end of the cylindrical member which with the end plate forms a V-shaped inlet chamber or recess opening into the compression chamber. The cylindrical member includes a suction port opening into this recess. A flexible V-shaped valve means for the port is anchored in the recess and includes one arm valving the port and another arm engaging the end plate to bias the valving arm into operative position relative to the port.

Description

BACKGROUND OF THE INVENTION

A well-known type of rotary compressor comprises a cylindrical wall member and end plates defining a compression chamber or cylinder, a rotor eccentrically mounted within the cylinder and a vane slidably mounted within the cylindrical wall for engagement with the periphery of the motor to divide the chamber into a high-pressure side and low-pressure side. In the operation of such a compressor, rotation of the rotor draws gas into the low pressure side and discharges the compressed gas through a discharge port communicating with the high-pressure side of the chamber on the opposite side of the vane from the low-pressure port. When such compressor operates intermittently, as for example when it forms part of a hermetic refrigeration system, valve means are provided in the discharge port for preventing high-pressure refrigerant from reverse flowing into the compressor chamber during periods when the compressor is not operating. For maximum efficiency, it also is desirable to prevent reverse flow through the suction port which may take place for example due to the leakage of high-pressure pressure gas between the rotor and the cylinder walls to the low pressure side and then to the low side of the system when the compressor is stopped. In known rotary compressor including suction port valving, the valve has normally been positioned in the suction passage at a point somewhat remote from the compression chamber and has frequently taken the form of a simple ball or check valve in the suction passage.

SUMMARY OF THE INVENTION

The present invention is directed particularly to the provision of an improved suction valve for a rotary compressor which is positioned relatively close to the compression chamber, which is of simple and low cost construction and which is maintained in operative position relative to the suction port by the cylindrical wall and end plate members of the compressor.

In accordance with the illustrated embodiment of the invention, there is provided a rotary compressor including a cylindrical wall member and end plate members defining a compression chamber or cylinder, a rotor eccentrically rotatable within the chamber and a vane slideably mounted into the cylindrical wall between the inlet and outlet ports and engaging the motor to divide the cylinder into high- and low-pressure sides. The cylindrical wall member is provided with a channel in a surface portion thereof overlapping an end plate member and the slanting bottom wall of this channel forms with the opposed surface portion of the end plate member a V-shaped recess or inlet chamber opening into the compression chamber. An inlet passage in the cylindrical member terminates in an inlet port in the slanting bottom wall of the channel. A generally V-shaped suction valve member for preventing reverse flow through the inlet port comprises a flexible arm generally overlying the slanting bottom wall of the channel with the free end thereof valving the port and base portion including a flange extending into a slot or groove in the slanting channel bottom wall for positioning the vale member within the recess. The valve is biased into operating engagement with the port by means of a pair of arms extending at an angle from the base into engagement with the opposed surface of the end plate member.

BRIEF DESCRIPTION OF THE DRAWING

In the accompanying drawing:

FIG. 1 is an elevational view, partly in cross section, of hermetic refrigerant compressor incorporating the present invention;

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1; and

FIG. 3 is an enlarged sectional view taken generally along line 3-of FIG. 2; and

FIG. 4 is a perspective view of a portion of the inlet port and valve portion of the present invention; and

FIG. 5 is a schematic view of a refrigeration system including the compressor of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

With reference to FIGS. 1 and 2 of the drawing, there is illustrated a hermetic compressor casing 1 in which there is disposed a rotary compressor unit 2 connected by means of a drive shaft 3 to a motor 4.

The compressor includes a cylindrical wall member or block 6 having an inner cylindrical surface which, in combination with upper and lower end plate members 8 and 9 respectively overlapping the upper and lower ends of the cylindrical wall member, define an annular compressor chamber 10. The rotor 11 is driven by an eccentric 12 formed on the shaft 3 within the cylinder 10. A vane 14 slidably disposed within a radial slot extending through the cylinder wall 6 continuously engages the periphery of the rotor to divide the cylinder 10 into a high-pressure side 16 and a low-pressure side 17.

Such hermetic compressors are particularly adapted to be connected into a refrigeration system such as that shown in FIG. 5 of the drawing so as to withdraw low-pressure or gaseous refrigerant from an evaporator 18 through a suction line 19 discharge high-pressure refrigerant through a discharge line 20 to a condenser 21. More specifically, low-pressure refrigerant is conducted to the low-pressure side 17 of the cylinder through an inlet passage 22 while high-pressure refrigerant from the high-pressure side 16 is discharged through a discharge port 24 in the upper end plate member 8 and a discharge valve (not shown) into the interior of the case 1 from which it flows into the discharge line 20.

The construction of the suction port and valve means of the present invention is illustrated in greater detail in FIGS. 3 and 4 of the drawing. A surface portion 26 of the cylindrical wall member 6 which is an overlapping relationship with a surface portion 27 of the lower end plate 9 includes a channel or recess 28 having a slanting bottom wall 29 and opposed sidewalls 30. This channel forms with the opposed surface portion 27 of the end plate member 9, a V-shpaed recess 31 opening into the compression chamber 10 or more specifically into the low side 17. The inlet or port end 32 of the inlet passage 22 opens into or through the slanting bottom wall 29.

A unitary or one piece vale means 34 formed of sheet metal is of a generally V-shape. It comprises, as shown particularly in FIG. 4 of the drawing, a base portion 35 forming one end of the vale means and including a flange 36 adapted to be received in groove 33 provided at the rear or outer end of the slanting wall 29 for positioning the valve in the recess 31. A flexible arm portion 37 of the valve, forming the main boy thereof extends from the base portion 35 along the channel wall 29 and terminates the annular valve member 38 overlying the port 32.

At least one arm, and preferably a pair of spaced arms, 39 struck from the body portion extend form the base portion 35 at an angle to and on opposite sides of the flexible arm 37. The primary function of the arms 39 is to bias the valve member 38 into operative or port closing position with reference to the port 32 by bearing against the surface portion 37 of the end plate 9. When two arms 39 are employed, the valve means may be of a width such that these arms also engage the opposed sidewalls 30 of the channel to aid in aligning the valve means within the channel.

In assemblying the compressor, the valve means 34 is positioned in the channel 28 with the flange 36 inserted into groove 33. End plate 9 is then placed on the cylindrical member 6 and fastened thereto by bolts 40. Thus no means other then the clamping of the valve 34 between the end plate 9 and the cylindrical wall member 6 is required to secure the vale means. During operation of the compressor, the flexible arm 37 of the vale means flexes between the port opening and closing positions and is biased to the port closing position by arms 39. Opening movement of the valve is limited by the surface portion 27 of the end plate opposite the port 32 or in other words the end plate functions as a valve backer or backing member.

While there has been shown and described a specific embodiment of the present invention it will be understood that it is not limited thereto and it is intended by the impended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.

Claims

I claim:

1. A rotary compressor comprising means including a cylindrical wall member and an end plate member defining an annular compression chamber;

said members including opposed surfaces defining a V-shaped recess opening into said chamber;

a suction port opening into one of said surfaces;

a V-shaped valve means for said port comprising a flexible arm overlying said one surface and having an end section forming a valve member for said port and a second arm engaging the other of said surfaces to maintain said valve member in operative engagement with said port; and

means for positioning said valve means in said recess including a groove in said one surface and a flange on said valve means extending into said groove.

2. A rotary compressor comprising means including a cylindrical wall member and an end plate member secured to said cylindrical wall member defining an annular compression chamber;

said members including overlapping surface portions;

the surface portion of said cylindrical wall member including a channel having a slanting bottom wall forming with the surface portion of said end plate a V-shaped recess having its wider front end opening into said chamber;

said channel including a groove therein adjacent the rear end of said recess;

said cylindrical member including an inlet passage therein terminating in an inlet portion in said slanting bottom wall; and

a unitary valve means disposed in said channel including a base portion having a flange thereon extending into said groove for positioning said valve means in said recess and a flexible arm extending from said base portion along said bottom wall and terminating in a valve member overlying said port;

said valve means including at least one arm extending from said base portion into engagement with said surface portion of said end plate member for maintaining said valve member in operative position relative to said port.

3. The compressor of claim 2 in which said valve means includes a pair of spaced arms engaging said end plate member.