JPH09137778A - Refrigerant compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To set valve stress of an intake reed valve in a proper magnitude by arranging a step part corresponding to a discharging hole on the opening circumferential rim of the discharging hole formed on a valve seat plate installed on the end part of a cylinder, and to improve volume efficiency of a compressor by minimizing volume increase due to the discharging hole. SOLUTION: The compressing element of a refrigerant compressor used for a refrigerator and the like is provided with a piston which is performed reciprocating operation by eccentric rotation of a crank pin, and a cylinder head is installed through a valve seat plate 15 on the end surface of the cylinder. In the valve seat plate 15, an intake hole 16 and a discharging hole 17 are formed. A step part 19 is arranged integratedly with the valve seat plate 15 on the opening circumferential rim of the discharging hole 17, and a valve plate 20 is interposed between the valve seat plate 15 and the cylinder. The step part 19 is formed so as to coincide with the discharging hole 23 when the valve plate 20 and the valve seat plate 15 are superposed on each other, and the step part 19 is inserted in the discharging hole 23 so as to improve a volume efficiency by reducing a top clearance volume.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerant compressor used in a refrigerator or the like, and more particularly to an improved valve device in a reciprocating refrigerant compressor.

[0002]

2. Description of the Related Art A conventional reciprocating type refrigerant compressor is disclosed in, for example, Japanese Patent Laid-Open No. 5-149256. In this compressor, a compression element that sucks and compresses a refrigerant from an external refrigerant circuit and an electric element that drives a piston thereof are housed in a closed container. The compression element is constructed by mounting a valve seat plate having suction holes and discharge holes at the end of the cylinder and further mounting a cylinder head. A suction reed valve is provided on the cylinder side of the valve seat plate, and a discharge reed valve is provided on the opposite side. The suction reed valve and the discharge reed valve open and close the openings of the suction hole and the discharge hole of the valve seat plate, respectively, according to the reciprocating movement of the piston in the cylinder.

As shown in FIG. 5, a suction reed valve 30 is formed by providing a reed valve-shaped slit 32 on a valve plate 31 made of a thin metal plate. Inhalation reed valve 30 arm 30
A discharge hole 33 is formed near the fulcrum 30B of C. The suction reed valve 30 faces the suction hole 35 and the discharge hole 36 formed in the valve seat plate 34 shown in FIG.
0A and a discharge hole 33 are provided. The valve plate 31 and the valve seat plate 34 are arranged in this order in the lid portion 3 of the suction reed valve 30.
0A and the discharge hole 33, the suction hole 35 of the valve seat plate 34, respectively.
The discharge holes 36 face each other and are attached to the cylinder end portion with bolts through the through holes 37. When attached to the end of the cylinder, the discharge hole 33 formed in the suction reed valve 30 becomes a top clearance volume in the cylinder as shown in the cross-sectional view of the main part near the discharge hole shown in FIG. Reduces the volumetric efficiency of the compressor. Therefore, the discharge hole 33 formed in the suction reed valve 30 is preferably the same size as the discharge hole 36 of the valve seat plate 34.

[0004]

However, since the discharge hole is located in the arm portion between the lid portion and the fulcrum of the suction reed valve, the valve stress of the suction reed valve depends on its shape and size. In order to eliminate the top clearance volume, the discharge hole has the smallest size (same size as the discharge hole).
If so, the valve stress increases, which makes it difficult to open the intake reed valve, which causes a delay in valve opening. In order to avoid this, if the shape of the discharge hole is made larger than the discharge hole, for example, an elliptical shape with the long axis facing the central axis direction of the suction reed valve to reduce valve stress, the top clearance volume becomes large as described above. The problem arises.

An object of the present invention is to solve this problem and to provide a refrigerant compressor having improved volumetric efficiency.

[0006]

SUMMARY OF THE INVENTION The present invention is directed to an electric element provided in a closed container, a compression element having a cylinder provided in the closed container and having a piston reciprocally driven by the electric element, and a suction element. A valve seat plate having a hole and a discharge hole and attached to the end of the cylinder; and a suction reed valve having a discharge hole larger than the discharge hole at a position corresponding to the lid and the discharge hole for opening and closing the opening of the suction hole. The provided refrigerant compressor is characterized in that a step portion corresponding to the discharge hole of the suction reed valve is provided on the opening peripheral edge of the discharge hole. In the compression stroke, the step portion enters the discharge hole with the intake reed valve closed, and the top clearance volume decreases.

The step portion is formed to have a height substantially equal to the plate thickness of the suction reed valve so as to minimize the volume increase due to the discharge hole without protruding into the cylinder.

The discharge hole can be formed in an elliptical shape whose major axis is oriented in the direction of the central axis of the suction reed valve, so that the valve stress can have an appropriate size without causing a valve opening delay.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of a refrigerant compressor of the present invention. In the figure, reference numeral 1 is a closed container composed of an upper container and a lower container, which are frame bodies 2 and 3 composed of two parts, a compression element 4 arranged above the frame bodies 2 and 3, and a lower part. The electric element 5 arranged on the side is housed. The compression element 4 and the electric element 5 are elastically attached to the inner wall of the closed container 1 via a support device 6.

The electric element 5 includes a stator 8 having a winding 7 wound therein, and a rotor 9 arranged inside the stator 8.
The rotor 9 is attached to the center of the rotor 9 and is constituted by a rotating shaft 11 rotatably supported by a bearing 10 of the frame body 2.

The compression element 4 includes a cylinder 12 and a rotary shaft 11.
The piston 14 that reciprocates in the cylinder 12 by the eccentric rotation of the crank pin 13, the valve seat plate 15 provided on the end surface of the cylinder 12, and the cylinder head attached to the cylinder 12 via the valve seat plate 15. 16 and 16.

The valve seat plate 15 is made of sintered metal and has a suction hole 16 and a discharge hole 17 as shown in the plan view of the cylinder shown in FIG. The refrigerant gas is sucked into the cylinder 12 from the external refrigeration circuit through the suction hole 16 according to the reciprocating movement of the piston 4, and is discharged to the outside of the cylinder 12 through the discharge hole 17. The groove 1 is formed around the opening of the suction hole 16.
A valve seat 18 is provided by 8A. A step portion 19 is provided integrally with the valve seat plate 15 at the peripheral edge of the opening of the discharge hole 17.

A space between the valve seat plate 15 and the cylinder 12 is shown in FIG.
The valve plate 20 shown in FIG. The valve plate 20 is the valve seat plate 1
5 is made of a metal thin plate having the same outer shape as that of 5, and the suction reed valve 22 is formed by the slit 21. The suction reed valve 22 has a lid portion 22A that opens and closes the opening of the suction hole 16 of the valve seat plate 15, and the discharge hole of the valve seat plate 15 is located near the fulcrum 22B of the arm portion 22C that connects the lid portion 22A to the fulcrum 22B. A discharge hole 23 is formed corresponding to 17. Discharge hole 23
Has a shape of an ellipse whose major axis is directed to the central axis of the suction reed valve 22, and its size is larger than that of the discharge hole 17 of the valve seat plate 15. The width of the arm portion 22C of the suction reed valve 22 can be made narrower as the discharge hole 23 is made larger.
The narrow portion can be lengthened by lengthening it in the direction of the central axis 2. As a result, the valve stress of the suction reed valve 22 can be reduced and the valve reed valve 22 can be made to have an appropriate size without causing a valve opening delay.

The valve plate 20 includes a lid portion 22 of the suction reed valve 22.
A closes the opening of the suction hole 16 of the valve seat plate 15,
The discharge holes 17 are overlapped so as to face the discharge holes 23 of the suction reed valve 22, and are attached to the end portion of the cylinder 12. The step portion 19 provided on the valve seat plate 15 is formed so as to match the discharge hole 23 when the valve plate 20 and the valve seat plate 15 are superposed, and as shown in the sectional view of FIG. The step portion 19 enters the discharge hole 23 to reduce the top clearance volume. The height of the step portion 19 is set to the same dimension as the plate thickness of the suction reed valve 22.

[0016]

As described above, in the refrigerant compressor of the present invention, the valve seat plate is provided with the step portion corresponding to the discharge hole of the suction reed valve, so that the valve stress of the suction reed valve can be appropriately adjusted. Therefore, even if the size of the discharge hole is increased, this step portion enters the discharge hole of the suction reed valve, and the volume increase due to the discharge hole is minimized to improve the volumetric efficiency of the compressor. You can

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a refrigerant compressor of the present invention.

FIG. 2 is a plan view showing a valve seat plate of the refrigerant compressor of the present invention.

FIG. 3 is a plan view showing a suction reed valve of the refrigerant compressor of the present invention.

FIG. 4 is a cross-sectional view of essential parts near a discharge hole of the refrigerant compressor of the present invention.

FIG. 5 is a plan view showing a suction reed valve of a conventional refrigerant compressor.

FIG. 6 is a plan view showing a valve seat plate of a conventional refrigerant compressor.

FIG. 7 is a cross-sectional view of essential parts near a discharge hole of a conventional refrigerant compressor.

[Explanation of symbols]

 1 Airtight Container 4 Compression Element 5 Electric Element 12 Cylinder 14 Piston 15 Valve Seat Plate 16 Suction Hole 17 Discharge Hole 19 Step 22 Suction Reed Valve 23 Discharge Hole

Claims (3)

[Claims] 1. A compression element having an electric element provided in a closed container, and a compression element having a cylinder provided in the closed container and having a piston reciprocally driven by the electric element.
A valve seat plate having suction and discharge holes formed therein and attached to the end of the cylinder, a lid portion for opening and closing the opening of the suction hole, and a discharge hole larger than the discharge hole at a position corresponding to the discharge hole. A refrigerant compressor provided with an intake reed valve, wherein a step portion corresponding to the discharge hole is provided at an opening peripheral edge of the discharge hole. 2. The refrigerant compressor according to claim 1, wherein the stepped portion has a height substantially equal to a plate thickness of the suction reed valve. 3. The refrigerant compressor according to claim 1, wherein the discharge hole is formed in an elliptical shape whose major axis is oriented in the central axis direction of the suction reed valve.