JPH05215088A - Rotary compressor - Google Patents

Abstract

PURPOSE: To ensure airtight sealing between a valve member and a valve seat even there exists manufacture deviation by offsetting the valve seat slightly upstream of pads on which the valve assembly rests and biasing the valve member and seat with a valve spring. CONSTITUTION: A valve seat 40 is positioned slightly upstream of mounting pads 42 and 44 with respect to a duct of gas coolant flowing out from a compression chamber. A backer support 54 distributes the pressure from a bolt 56 uniformly to end portions of members in alignment with the pad 42. When the pressure of the gas coolant at high-pressure side of the compression chamber is increased to a predetermined level, a seal 62 of a valve member 48 is bent upward against the force of a spring 50 so that gas passes between the seal 62 and the valve seat 40. At that time, the center of the valve seat 40 and the center of the seal 62 are disposed such that an end edge 74 and the region of engagement of a tip 70 of a spring backer 52 with a tip 60 of the valve member 48 come substantially to the center. Thus, the seal 62 can move at right angle to the valve seat in an ensured way when it is opened and closed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary compressor, and more particularly to a rotary compressor having an improved span type discharge valve assembly.

[0002]

2. Description of the Related Art A typical rotary compressor includes an airtight outer casing, in which a refrigerant or other gas compressor unit is provided. The compressor unit includes a cylindrical side wall defining a cylindrical compression chamber and a pair of end plates. A roller is arranged in the compression chamber, and the roller is driven by an eccentric wheel formed on a motor-driven drive shaft. A vane is mounted on the cylindrical wall and strikes a roller to divide the compression chamber into a low pressure side and a high pressure side. A discharge passage extends through one of the end plates and connects the high pressure side to the inside of the casing outside the compressor unit. A valve seat is provided on the outer surface of the end plate so as to surround the end of the discharge passage. A flapper valve mechanism is mounted on one side of the valve seat and straddles the valve seat. The valve mechanism opens when the pressure of the refrigerant reaches a predetermined high level, allowing high pressure gas to exit the compression chamber into the space within the casing. The valve opens and closes very quickly, eg, at a rate of about 4/1000 seconds or less.
Further, it is desirable that the valve action is light and there is no flutter (irregular vibration). Rather than opening or closing the flapper valve at a right angle to the valve seat, the flapper valve tends to open from the side opposite its mount and close to the opposite. Further, the flapper valve oscillates from one side to the other and from end to end,
It tends to exhibit a reed action of twisting about its longitudinal axis. All of these features impair the optimal operation of the valve assembly.

[0003]

An object of the present invention is to provide a rotary compressor having an improved discharge valve mechanism. Another object of the present invention is to provide a rotary compressor whose discharge valve operates quickly and reliably. Another object of the present invention is to provide a rotary compressor having a span valve type discharge valve.

[0004]

SUMMARY OF THE INVENTION A rotary compressor in one form of the invention includes a cylindrical sidewall defining a compression chamber having a low pressure side and a high pressure side and a pair of end plates. A discharge passage extends through one end plate, and a valve seat is provided on the outer surface of the end plate to surround the discharge passage. A pair of mounting pads are formed on both sides of the valve seat. An elongated valve member, the ends of which are located on these pads, straddles the valve seat and seals the valve seat during normal times and away from the valve seat when a predetermined pressure is in the compression chamber. An elongate spring backing overlies the valve member, with the tips of the spring backing respectively located on the tip of the valve member. By passing the bolt through the end plate, one tip of the valve member and the spring backing is fixed to the corresponding pad. The other tip of the spring backing allows the other tip of the valve member to slide longitudinally as the valve member opens and closes, but the tip of the valve member is separated from other pads. Press (bias) the contact relationship.

[0005]

[Specific Structure] Here, US Pat. No. 46053 of GE Sturgeon et al. Assigned to the present applicant.
No. 62 (issued on August 12, 1986) is incorporated as a prior application. In the rotary compressor disclosed in this patent, the rotary compressor unit is mounted in a hermetically sealed outer casing. The flapper valve mounted on one end plate controls the discharge of high-pressure refrigerant from the compressor unit to the airtight casing outside the unit.

The present invention will be described below with reference to the drawings. 1 and 2 are an exploded view and a top plan view of a compressor unit of an airtight refrigeration compressor according to an embodiment of the present invention. The rotary compressor unit 10 has an annular compression chamber 12, which is defined in a cylindrical side wall 14 and is surrounded by end plates 16 and 18. The roller 20 is rotatably arranged in the compression chamber 12, and is driven by an eccentric wheel 22 formed integrally with a drive shaft 24. Shaft 24 is supported by suitable bearings on both end plates and is rotated by a suitable electric motor (not shown) as is well known in the art.

The cylinder 14 is provided with a slot 26 extending in the radial direction, and a vane 28 is slidably accommodated in the slot 26. A spring 30 (see FIG. 2) presses (biases) the vane 28 into contact with the outer surface of the roller 20 and divides the compression chamber 12 into a low pressure side and a high pressure side. The shaft 24 rotates the roller 20 in the compression chamber 12 counterclockwise (as viewed in FIG. 1), sucks low-pressure refrigerant gas into the compression chamber 12 through the inlet passage 32, and discharges high-pressure compressed refrigerant gas through the channel 34. Spit out. 3 and 4
As is clear from the above, the discharge passage 36 provided in the end plate 16 communicates with the discharge channel 34, and the high-pressure gas flows out of the compression chamber 12 into the space inside the airtight casing outside the compressor unit 10. go. A muffler 38 (see FIG. 1) is arranged on the end plate 16 to reduce the transmission of noise generated by the refrigerant flowing out.

A circular or ring-shaped valve seat 40 is provided at the outer end or outlet end of the passage 36. As is apparent from FIG. 1, the valve seat 40 is arranged in a shallow recess on the outer surface of the end plate 16. A pair of mounting pads 42 and 44 are formed on the outer surface of the end plate 16 and are arranged at intervals so as to come to both sides of the valve seat 40. As can be seen in FIGS. 3 and 4, the outer edge of the valve seat 40 is slightly lower than the substantially coplanar mounting pads 42 and 44. In this way, the valve seat 40 is positioned slightly upstream of the mounting pads 42 and 44 with respect to the passage of the refrigerant gas exiting the compression chamber 12.

The valve assembly 46 includes a valve member 48, a valve spring 50, a spring backing 52, a backing support 54, and bolts 56. The valve member 48 straddles the valve seat 40 and includes spaced apart tips 58 and 60 located on the pads 42 and 44, respectively. Valve member 4
A generally circular seal portion 62 is provided at the center of 8, and the seal portion 62 is aligned with the valve seat 40 and is large enough to completely cover the valve seat. Valve spring 50
Includes a first end 64 located on the tip 58 of the valve member 48 and a circular end 66 engaging the circular seal 62 of the valve member 48. The spring backing 52 has a first end 68 located on the end 64 of the valve spring 50.
And a second end 70 that engages the tip 60 of the valve member 48. The middle portion 72 of the spring backing 52 is curved and draws an arc in a direction away from the valve seat 40,
It provides clearance for operation of the valve assembly as described below. The backing support 54 is located on the first end 68 of the spring backing 52 and includes an edge 74 that is generally perpendicular to the longitudinal axis of the valve assembly 46. These parts of the valve assembly 46 are
6 on the end plate 16 by means of bolts 56, which are arranged in the above-mentioned shape, through the holes of the various parts of the assembly and screwed into the threaded openings 76 of the end plate 16.
Held in. The backing support 54 evenly distributes the pressure from the bolt 56 to the end of the member that is aligned with the pad 42, and the edge 74 of the backing support 54 provides a baseline through which the valve member 48 and the valve spring 50 bend during operation. Stipulates.

In normal times, the valve assembly 46 assumes the configuration shown in FIG. That is, the circular end 66 of the spring 50 biases the center of the valve member 48 downward, and the seal 62 forms an airtight seal with the valve seat 40. When the pressure of the refrigerant gas on the high pressure side of the compression chamber 12 increases to a predetermined level, the seal portion 62 of the valve member 48 warps upward against the force of the valve spring 50 to the position shown in FIG. 4, and the gas is sealed. Part 62
And the valve seat 40. When the pressure in the compression chamber 12 is sufficiently reduced, the valve assembly 46 returns to the arrangement shown in FIG. As the valve member 48 and valve spring 50 move between open and closed positions, the valve member 48 and valve spring 50 bend about a baseline defined by an edge 74 of the backing support 54. The length and position of the various parts are such that the center of the valve seat 40 and the center of the seal 62 are
The edge 74 and the tip portion 70 of the spring backing 52 are attached to the valve member 48.
Are approximately centered between the tip 60 and the area of engagement. By doing so, it is possible to ensure that the seal portion 62 moves substantially perpendicularly to the valve seat 40 when opening and closing the seal portion 62. The pressure applied by the tip portion 70 to the tip portion 60 is such that the valve member 48 causes the pad 44 to move when the valve is opened and closed.
While allowing it to slide up, the tip 60 of the valve member 48
The tip 6 to prevent the
Press 0 (bias). Rounding the edges of the tip 60 to prevent the edges from biting into the surface of the pad 44 facilitates such operation. Further, the above-described shape of the span valve assembly 46 minimizes flutter on the valve member 48. In one example of a valve assembly, the valve member is constructed from 6 mil high carbon spring steel, the valve spring is constructed from 8 mil high carbon spring steel, and the spring backing is constructed from 20 mil high carbon spring steel. The padding support was constructed from 20 mil low carbon steel.

In the embodiment of FIGS. 1-4, the valve seat 40 is offset slightly upstream of the pad on which the valve assembly is mounted and the valve spring biases the valve member toward the valve seat. This ensures an airtight seal between the valve member and the valve seat, despite variations due to the manufacturing method. If time and expense are incurred during the manufacturing process to ensure extremely close tolerances, a simple assembly as shown in FIGS. 5-7 is preferred. Since the structure is similar to that shown in FIGS. 1-4, the same parts are designated with the same reference numerals. In this example,
The valve seat 40 is substantially flush with the pads 42 and 44. The seal portion 62 of the valve member 48 is seated on the valve seat 40 without requiring a force from the outside, so the valve spring is omitted. In other respects, this embodiment has the same structure and operation as the embodiment of FIGS.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a compressor unit of an airtight refrigeration compressor incorporating an embodiment of the present invention.

2 is a top plan view of the compressor unit of FIG. 1. FIG.

FIG. 3 is a partial cross-sectional view taken along line 3-3 of FIG. 2, showing the span valve mechanism in the closed position.

FIG. 4 is a partial cross-sectional view similar to FIG. 3, showing the span valve in the open position.

5 is a partially exploded perspective view similar to FIG. 1 incorporating another span valve assembly.

6 is a partial cross-sectional view similar to FIG. 3, showing the span valve assembly of FIG. 5 in a closed position.

7 is a partial cross-sectional view similar to FIG. 6, showing the span valve assembly of FIG. 5 in an open position.

[Explanation of symbols]

 10 compressor unit 12 compression chamber 14 side wall 16, 18 end plate 20 roller 28 vane 32 inlet passage 36 discharge passage 40 valve seat 42, 44 pad 46 valve assembly 48 valve member 50 valve spring 52 spring backing 54 backing support 56 Bolt 58, 60 Valve member tip portion 62 Seal portion 68 Spring backing first end portion 70 Spring backing second end portion

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor James Floyd Gordon No. 527, Leicester Circle, Lewisville, Kentucky, USA

Claims (7)

[Claims] 1. A cylindrical side wall defining a compression chamber having a low pressure side and a high pressure side and a pair of end plates, and penetrating the first end plate from the high pressure side of the compression chamber. A single high pressure discharge passage, a valve seat provided on the outer surface of the first end plate so as to surround the passage, and formed on both sides of the valve seat on the outer surface of the first end plate. First and second pads, and a first tip portion supported from the first pad,
A second tip portion supported from the second pad;
A unit that overlaps the valve seat, seals the valve seat in normal times, and has an intermediate portion that is separated from the valve seat when a predetermined high pressure is on the high pressure side of the compression chamber. An elongated valve member, the valve member overlapping the first and second valve members;
A spring backing including first and second ends respectively engaged with the tip of the valve, and securing the first end of each of the valve member and the spring backing to a corresponding pad. The second end of the spring backing is configured such that when the intermediate portion of the valve member moves away from the valve seat, the second tip portion of the valve member has the second end. A rotary compressor that allows movement in the longitudinal direction of the pad, but presses the second tip of the valve member away from the second pad. 2. An elongated valve spring having a first end secured to the first pad between the valve member and the spring backing, the valve spring comprising: The rotary compressor according to claim 1, wherein the intermediate portion of the valve member is engaged with the intermediate portion so as to elastically press the intermediate portion with the valve seat. 3. The rotary compressor according to claim 1, wherein the pad and the valve seat are all substantially in the same plane. 4. The rotary compressor according to claim 2, wherein the pad is substantially in the same plane, and the valve seat is upstream of the outlet passage with respect to the pad. 5. Further comprising a backing support secured to the first end of the spring backing opposite the valve member, the backing support extending along the spring backing. The spring backing and the second end of the spring backing and the valve member between the spring backing and the end of the backing support. The rotary compressor according to claim 1, wherein the rotary compressor is formed as an arc protruding from the engagement member in a direction away from the valve member. 6. The rotary compressor according to claim 5, wherein the valve seat is located substantially in the center between the end portion of the backing support and the engagement portion of the spring backing and the valve member. .. 7. The valve seat is generally circular in cross section, and the intermediate portion of the valve member includes a generally circular portion disposed in an aligned relationship with the valve seat and having a larger diameter than the valve seat. The rotary compressor according to claim 1, wherein: