JP2000291558A - Hermetic compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce noise and vibration in the intake valve of a hermetic compressor. SOLUTION: This compressor is equipped with a piston, a cylinder, a cylinder head, a valve plate 24 having an intake hole 9, a valve seat groove 22 formed around the circumference of the intake hole 9 at the cylinder side of the valve plate 24, an intake valve 23 interposed between the valve plate 24 and the cylinder, and a curved part for projecting the tip end of the intake valve 23 to the cylinder side. Noise can be reduced, and reliability can be made high, while cooling performance is being maintained as is by preventing the valve 23 from being brought into contact with the piston, when it is opened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic compressor used for a refrigerator or the like.

[0002]

2. Description of the Related Art In recent years, hermetic compressors (hereinafter referred to as compressors) have been required to have high energy efficiency. Therefore, valve devices such as suction valves and discharge valves have been improved. For example, Japanese Patent Application Laid-Open No.
No. 45781.

An example of the above-described conventional valve device will be described below with reference to the drawings.

FIG. 12 is a longitudinal sectional view of a conventional compressor.
13 is a sectional view of a main part of a compression unit of the conventional compressor, FIG. 14 is a sectional view of a main part of a suction valve and a valve plate of the conventional compressor, and FIG. 15 is a suction valve of the conventional compressor. Is a front view from the cylinder head side,
FIG. 16 is a front view of a valve plate of a conventional compressor as viewed from a cylinder head side. Reference numeral 1 denotes an airtight container, 2 denotes a mechanical portion elastically supported in the airtight container 1, 3 denotes a motor portion disposed above the mechanical portion 2, and 4 denotes a cylinder head constituting the mechanical portion 2. A muffler 5 is inserted into the cylinder head 4. 6 is a cylinder, 7 is a piston. Reference numeral 8 denotes a valve plate having a suction hole 9 and a discharge hole 10. Reference numeral 11 denotes a suction valve which is installed from the cylinder 6 side of the valve plate 8. Reference numeral 12 denotes a plate gasket provided between the suction valve 11 and the cylinder 6. Reference numeral 13 denotes a head gasket provided between the cylinder head 4 and the plate gasket 12. 1
4 is a discharge valve, a discharge lead 15 and a spring lead 1.
6 and two rivets 17 are formed by a lead stopper 18 fixed to the valve plate 8. Further, a discharge chamber 19 and a suction chamber 20 are formed by the cylinder head 4 and the valve plate 8. Also, 2
1 is a valve seat provided around the suction hole 9 on the cylinder 6 side of the valve plate 8, and 22 is a valve seat groove provided around the valve seat 21.

[0005] Regarding the compressor configured as described above,
The operation will be described below.

[0006] The motor unit 3 drives the piston 7 and the like of the mechanical unit 2, and in the suction stroke, the refrigerant is sucked into the muffler 5 from a suction path (not shown) and passes through a suction chamber 20 in the cylinder head 4. It is sucked into the cylinder 6 intermittently. Further, in the discharge stroke, the liquid is discharged from the cylinder 6 through the discharge chamber 19 in the cylinder head 4.

A series of refrigerant flows from the suction to the discharge stroke in the cylinder 6 will now be described in detail. When the piston 7 moves toward the bottom dead center, the pressure in the cylinder 6 decreases and the pressure in the cylinder head 4 decreases. Since the difference from the pressure becomes large, the discharge lead 15 closes and the suction valve 11 opens, so that the refrigerant is drawn into the cylinder 6 from the suction chamber 20 of the cylinder head 4 through the suction hole 9. Further, when the piston 7 reaches the bottom dead center and the suction stroke is completed, the piston 7 starts to move to the top dead center side, the pressure in the cylinder 6 starts to rise, and the discharge chamber 19 of the cylinder head 4 starts.
The suction valve 11 is closed, the discharge lead 15 is opened, and the compressed refrigerant gas in the cylinder 6 passes through the discharge hole 10 of the valve plate 8 and the discharge chamber 19 Is discharged. The suction valve 11 and the discharge valve 14 have a structure that opens and closes quickly when a small pressure difference occurs between the front and rear refrigerant passages, so that the suction efficiency of the refrigerant gas during the suction stroke is good, and Since the leakage of the refrigerant gas from the suction holes 9 during the discharge stroke is relatively small, a stable refrigerant circulation amount is obtained, and the refrigeration capacity is maintained at a relatively high level. by the way,
The opening and closing movement of the suction valve is determined by physical properties such as a natural frequency and a spring constant determined by the thickness and shape of the suction valve.

[0008]

However, in the above-described conventional configuration, when the piston is started under a condition where the low pressure is relatively high, such as when the high and low pressures are balanced before the start, the piston in the initial stage of the suction stroke is not operated. At the stage near the top dead center, the opening and closing speed of the suction valve 11 is faster than the traveling speed of the piston 7, so that the suction valve 1 having the maximum displacement amount
There was a possibility that one tip portion caused local metal contact with the upper end surface of the piston 7 and generated excessive noise and vibration. In addition, there is a disadvantage that an excessive impact force may be generated in the suction valve 11 that comes into contact with the metal to cause fatigue failure.

SUMMARY OF THE INVENTION The present invention solves the conventional problems, and eliminates the contact with the piston 7 when the suction valve 11 opens while maintaining the cooling performance, thereby achieving a hermetic compression system capable of low noise and high reliability. The purpose is to provide a machine.

Another object of the present invention is to reduce noise and vibration by maintaining the cooling performance and reducing the impact force caused by the contact between the suction valve 11 and the piston 7 when the suction valve 11 is opened during the suction stroke. At the same time as the suction valve 1
It is an object of the present invention to provide a hermetic compressor capable of preventing fatigue fracture of item 1.

Further, in the above-described conventional configuration, the suction valve 11 vibrates several times during the suction stroke, so that the cylinder 6
Due to a decrease in the amount of refrigerant gas sucked into the cylinder or a delay in closing the suction valve 11 during the compression stroke, the amount of refrigerant flowing backward from the cylinder 6 to the suction hole 9 increases, and the volume efficiency and efficiency decrease. There was a drawback that there was a possibility.

Another object of the present invention is to control the opening / closing behavior of the suction valve 11 to increase the amount of refrigerant gas sucked and to minimize the reverse flow from the cylinder 6 to the suction hole 9 side. It is an object of the present invention to provide a hermetic compressor capable of improving the refrigerating capacity and efficiency.

In the above-described conventional configuration, the suction valve 1
No. 1 has a disadvantage that the cooling performance is high only at a certain specific operating frequency, and when a plurality of operating frequencies such as an inverter operation are used, the cooling performance may be extremely lowered in other frequency ranges.

Another object of the present invention is to arrange a plurality of movable parts of the suction valve 11 and control the suction valve 11 corresponding to a plurality of operating frequencies such as an inverter operation so that a plurality of operating frequencies can be used. It is an object of the present invention to provide a hermetic compressor capable of improving the refrigerating capacity and efficiency.

[0015]

SUMMARY OF THE INVENTION In order to solve this problem, the present invention comprises a piston, a cylinder, a cylinder head, a valve plate having a suction hole, and a valve plate around a cylinder-side suction hole of the valve plate. And a suction valve disposed between the valve plate and the cylinder. The suction valve has a characteristic that has a curved portion in which the tip of the suction valve is convex toward the cylinder.

[0016] This eliminates contact with the piston when the suction valve opens while maintaining the cooling performance, thereby enabling low noise and high reliability.

Further, the present invention provides a structure including a piston, a cylinder, a cushioning material provided on an end face of the piston, a cylinder head, a valve plate, and a suction valve installed between the valve plate and the cylinder. It was.

Thus, while maintaining the cooling performance, when the suction valve is opened during the suction stroke, the impact force due to the contact between the suction valve and the piston is reduced to reduce noise and vibration, and at the same time, to reduce the fatigue of the suction valve. Prevent destruction,
High reliability is obtained.

The present invention also provides a piston, a cylinder, a cylinder head, a valve plate, a suction valve installed between the valve plate and the cylinder, an electromagnet provided near the top dead center of the cylinder, The configuration includes an energization control device that detects the behavior of the piston and energizes the electromagnet.

By controlling the opening and closing behavior of the suction valve, the amount of refrigerant gas suctioned is increased, and the reverse flow from the inside of the cylinder to the suction hole side is minimized, thereby improving the refrigeration capacity and efficiency. Is obtained.

Further, the present invention provides a piston, a cylinder, a cylinder head, a valve plate having a plurality of suction holes, a switching valve for switching the plurality of suction holes, an electromagnet for driving the switching valve, The configuration includes a suction valve having a plurality of movable parts disposed between a valve plate and a cylinder, and a valve opening / closing control device that detects an operation frequency and supplies a current to an electromagnet.

Thus, by arranging a plurality of movable portions of the suction valve and controlling the use of the suction valve 11 corresponding to a plurality of operating frequencies such as an inverter operation, the refrigerating capacity and efficiency can be improved at a plurality of operating frequencies. Is obtained.

[0023]

DETAILED DESCRIPTION OF THE INVENTION According to the first aspect of the present invention, a piston, a cylinder, a cylinder head,
A valve plate provided with a suction hole, a valve seat groove formed around the suction hole on the cylinder side of the valve plate, and a suction valve installed between the valve plate and the cylinder; The tip of the valve has a curved portion that is convex toward the cylinder side, and when the suction valve starts to open, the opening amount of the suction valve increases when the low pressure is high, such as at the beginning of startup, The tip of the suction valve is curved and does not contact the piston. As a result, the reliability of the suction valve can be improved, and noise can be reduced. Also, since the shape of the suction valve is the same as the conventional one only by bending the tip,
By maintaining the physical properties of the suction valve at about the same level as before, it has the effect of maintaining the cooling performance.

According to a second aspect of the present invention, a piston, a cylinder, a cushioning material provided on an end surface of the piston, a cylinder head, a valve plate, and a valve plate are provided between the valve plate and the cylinder. When the suction valve starts to open, when the low pressure is high, such as at the beginning of startup, the opening amount of the suction valve increases, and the piston contacts the top dead center. In this contact, the suction valve comes into contact with the cushioning material of the piston, so that the impact force of the valve due to the contact is reduced, thereby reducing valve fatigue and improving reliability. Further, noise and vibration can be prevented.

Further, since the shape of the suction valve is the same as that of the related art, it has an effect of maintaining the cooling performance by maintaining the physical properties of the suction valve at the same level as the related art.

According to a third aspect of the present invention, a piston, a cylinder, a cylinder head, a valve plate,
A suction valve installed between the valve plate and the cylinder, an electromagnet provided near the top dead center of the cylinder, and an energization control device that detects the behavior of the piston and energizes the electromagnet, Ideal suction valve behavior is obtained by minimizing the number of vibrations from opening to closing of the suction valve and increasing the maximum displacement of the valve, maximizing the refrigerant gas suction amount and compressing Since the reverse flow rate of the refrigerant gas from the inside of the cylinder to the suction hole side due to the delay of closing the suction valve in the stroke can be suppressed to a minimum, the effect of improving the refrigeration capacity and efficiency can be obtained.

According to a fourth aspect of the present invention, a piston, a cylinder, a cylinder head, a valve plate having a plurality of suction holes, a switching valve for switching between the plurality of suction holes, and the switching valve are provided. An electromagnet to be driven, a suction valve having a plurality of movable parts disposed between the valve plate and the cylinder, and a valve opening / closing control device that detects an operating frequency and energizes the electromagnet; By using a valve opening / closing control mechanism provided on the valve plate to enable selection of the intake valve in response to a plurality of specific operating frequencies such as inverter motion, a wide range of operating frequencies can be supported. It has the effect of improving the refrigeration capacity and efficiency.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a hermetic compressor according to the present invention will be described below with reference to the drawings. The same components as those of the related art are denoted by the same reference numerals, and detailed description is omitted.

(Embodiment 1) FIG. 1 is a sectional view of a main part of a compression unit of a hermetic compressor according to Embodiment 1 of the present invention.
FIG. 2 is a sectional view of a main part of the suction valve and the valve plate when the suction valve of the hermetic compressor of the embodiment is opened and closed.

In FIGS. 1 and 2, reference numeral 23 denotes a suction valve installed between a valve plate and a cylinder. 23
a is a curved portion where the tip of the suction valve is convex to the cylinder. Reference numeral 24 denotes a valve plate having the suction hole 9 and having a valve seat groove formed around the suction hole 9.

The operation of the hermetic compressor constructed as described above will be described below.

When the suction valve 23 is closed, the curved portion 23a of the suction valve 23 is in a state of fitting into the valve seat groove 22, and when the suction stroke is started, the piston 7 is moved from the top dead center to the bottom dead center. Moving to the point, the pressure drop in cylinder 6 begins. Then, at the same time as a certain pressure difference is created between the refrigerant pressure in the cylinder 6 and the refrigerant pressure in the cylinder head 4, the suction valve 23 starts to open. At this time, if the low pressure is high, such as at the beginning of startup, the opening amount of the suction valve 23 increases, but the tip of the suction valve 23 is curved and does not contact the piston 7. Thereby, the suction valve 2
3 can be improved, and noise can be reduced. Also,
Since the shape of the suction valve 23 is the same as the conventional one only by bending the tip, the cooling performance can be maintained by maintaining the physical properties of the suction valve 23 at the same level as the conventional one.

As described above, the hermetic compressor according to the present embodiment includes the piston 7, the cylinder 6, the cylinder head 4, the valve plate 24 having the suction hole 9, and the valve plate 24 on the cylinder 6 side. Valve seat groove 22 formed around suction hole 9, valve plate 24 and cylinder 6
And a curved portion 23a in which the tip of the suction valve 23 is convex toward the cylinder 6 side.
With this configuration, contact with the piston 7 when the suction valve 23 opens while maintaining the cooling performance is eliminated, thereby enabling low noise and high reliability.

(Embodiment 2) FIG. 3 is a sectional view of a main part of a compression unit of a hermetic compressor according to Embodiment 2 of the present invention.
FIG. 4 is a cross-sectional view of main parts of the suction valve, the valve plate, and the piston when the suction valve of the hermetic compressor of the embodiment is opened.

3 and 4, reference numeral 25 denotes a piston. 26 is a cushioning material provided on the end face of the piston 25. 27 is a suction valve provided between the cylinder and the valve plate.

The operation of the hermetic compressor constructed as described above will be described below.

The piston 25 moves from the top dead center to the bottom dead center, and the pressure in the cylinder 6 starts to decrease. Then, at the same time as the pressure difference between the refrigerant gas in the cylinder 6 and the refrigerant gas in the cylinder head 4 increases, the suction valve 27 starts to open. At this time,
When the low pressure is high, such as at the beginning of startup, the opening amount of the suction valve 27 increases, and the piston 25 comes into contact with the top dead center. In this contact, the suction valve 27 comes into contact with the cushioning material 26 of the piston 25, so that the impact force of the valve due to the contact can be reduced, thereby reducing the valve fatigue and improving the reliability.
Further, noise and vibration can be prevented.

Since the shape of the suction valve 27 is the same as the conventional one, the cooling performance can be maintained by maintaining the physical properties of the suction valve 27 at the same level as the conventional one.

As a condition for the contact between the suction valve 27 and the piston 25, there is a sudden liquid return during the start-up operation. In this case, the same effect can be obtained.

As described above, the hermetic compressor according to the present embodiment includes the piston 25, the cylinder 6, the cushioning material 26 provided on the end face of the piston 25, and the cylinder head 4.
, A valve plate 8, and a suction valve 27 installed between the valve plate 8 and the cylinder 6. During the suction stroke, the inside of the cylinder 6 and the cylinder head 4 is maintained while maintaining the same high cooling performance as before. When the suction valve 27 opens due to the pressure difference of the refrigerant gas, the suction force of the suction valve 27 contacting the piston 25
And the noise and vibration are reduced, and at the same time, the intake valve 27 is prevented from being broken due to metal contact, and high reliability is obtained.

(Embodiment 3) FIG. 5 is a sectional view of a main part of a compression unit when a suction valve of a hermetic compressor according to Embodiment 3 of the present invention is closed, and FIG. FIG. 2 is a sectional view of a main part of a compression unit when a suction valve of the compressor is open. FIG. 7 is a graph showing displacement characteristics of the suction valve and the piston with respect to the crank angle of the hermetic compressor of the embodiment.

In FIGS. 5, 6, and 7, reference numeral 28 denotes a suction valve provided between the valve plate and the cylinder, 29 denotes an electromagnet provided near the top dead center of the cylinder, and 30 denotes a piston. Is an energization control device that detects the behavior of the electromagnet and energizes the electromagnet.

The operation of the hermetic compressor configured as described above will be described below.

As shown in FIG. 7, the conventional suction valve enters the suction stroke, the suction valve 28 is opened, and the valve is closed at about 220 ° by repeating three valve oscillations. Here, it is known from our investigation that when the suction valve closes at around a crank angle of 200 °, the amount of refrigerant gas leaking from the inside of the cylinder 6 to the suction hole 9 side is extremely small, and the refrigeration capacity and efficiency are high. By controlling the suction valve 28 by the power supply control device 30, the suction valve 2 shown in FIG.
When the piston 7 moves to the bottom dead center side from the closed state of 8 and the opening movement of the suction valve 28 starts, at the same time, the energization of the electromagnet 29 from the energization control device 30 that has detected the crank angle starts, and A maximum displacement of 28 is obtained. Next, the suction valve 28 starts to close and the crank angle becomes 2
Since control is performed such that the valve closes at 00 ° and the valve opening / closing operation is performed only once to prevent a decrease in the refrigerant circulation amount due to the valve displacement amount oscillating, ideal suction valve behavior is obtained. Refrigeration capacity and efficiency are increased because the volume is improved and leakage losses during the discharge stroke are minimized.

As described above, the hermetic compressor according to the present embodiment includes the piston 7, the cylinder 6, the cylinder head 4, the valve plate 8, and the suction valve provided between the valve plate 8 and the cylinder 6. 28, an electromagnet 29 provided near the top dead center of the cylinder 6, and an energization control device 30 for detecting the behavior of the piston 7 and energizing the electromagnet 29. The number of vibrations is minimized and the suction valve 2
By increasing the maximum displacement of 8, the suction amount of the refrigerant gas is maximized. Further, the reverse flow rate of the refrigerant gas from the cylinder 6 to the suction hole 9 in the compression stroke can be minimized, so that the refrigerating capacity and efficiency can be improved.

(Embodiment 4) FIG. 8 is a sectional view of a main part of a compression unit of a hermetic compressor according to Embodiment 4 of the present invention.
FIG. 9 is a front view of a suction valve of the hermetic compressor of the embodiment. FIG. 10 is a front view of a valve plate of the hermetic compressor of the embodiment. FIG. 11 is a flowchart showing the operation of the control device of the hermetic compressor of the embodiment.

In FIGS. 8, 9, 10 and 11, 3
1 is a valve plate. Reference numeral 32 denotes a suction valve provided between the valve plate and the cylinder. 32a is a movable part of the suction valve. 33 is a valve plate 31
Are a plurality of suction holes. A switching valve 34 switches between a plurality of suction holes. An electromagnet 35 drives the switching valve 34.

Numeral 36 denotes a valve opening / closing control device for detecting the operating frequency and energizing the electromagnet.

The operation of the hermetic compressor configured as described above will be described below.

For example, at the time of the 50/60 Hz combined operation, the movable portions 32a of the two intake valves 32 having the optimum physical values at 50/60 Hz as shown in FIG. By the control device 36, at the time of 50 Hz operation, the operating frequency is sensed and electromagnetically transmitted to one of the electromagnets 35 to draw the switching valve 34, and the other electromagnet 35 is degassed.
When one of the suction holes 33 is closed and the other is opened, 5
Since the movable portion 32a of the suction valve 32 dedicated to 0 Hz can be used, the refrigeration capacity and efficiency are improved. In addition, at the time of 60 Hz operation, the refrigerating capacity and efficiency are improved by using the other suction valve 32 in the same manner.

Although the number of the movable portions 32a of the suction valve 32 is two in this case, the movable portions 32a, the suction holes 33, and the electromagnets 35 of the plurality of suction valves 32 are changed according to a plurality of operating frequencies.
The same effect can be obtained by providing the switching valve 34.

As described above, the hermetic compressor of this embodiment is
Piston 7, cylinder 6, cylinder head 4
A valve plate 31 having a plurality of suction holes 33;
Switching valve 34 for switching a plurality of suction holes 33
And an electromagnet 35 for driving a switching valve 34, a suction valve 32 having a plurality of movable parts 32a installed between the valve plate 31 and the cylinder 6, and a valve opening / closing control for detecting an operating frequency and energizing the electromagnet 35 And a plurality of suction valves 32.
By using a valve opening / closing control mechanism 36 provided on the valve plate 31 so that the suction valve 32 can be selected according to a plurality of specific operating frequencies such as an inverter operation, the refrigeration capacity and efficiency corresponding to a plurality of operating frequencies are provided. Is obtained.

[0053]

As described above, the first aspect of the present invention comprises a piston, a cylinder, a cylinder head, a valve plate provided with a suction hole, and a valve plate provided around a cylinder-side suction hole. Valve seat groove, and a suction valve installed between the valve plate and the cylinder.The suction valve has a curved portion with the tip of the suction valve protruding toward the cylinder. Eliminating contact with the piston when the valve opens, enabling low noise and high reliability.

According to a second aspect of the present invention, there is provided a piston, a cylinder, a cushioning material provided on an end face of the piston, a cylinder head, a valve plate, and a suction member provided between the valve plate and the cylinder. Consisting of a valve, while maintaining the same high cooling performance as before, the impact force that the suction valve contacts the piston when the suction valve opens due to the pressure difference between the cylinder and the refrigerant bus in the cylinder head during the suction stroke Is reduced by the cushioning material of the piston, so that noise and vibration are reduced, and at the same time, fatigue fracture due to metal contact of the suction valve is prevented, and high reliability is obtained.

According to the third aspect of the present invention, a piston, a cylinder, a cylinder head, a valve plate, a suction valve installed between the valve plate and the cylinder, and a cylinder near the top dead center are provided. And the energization control device that detects the behavior of the piston and energizes the electromagnet, minimizes the number of vibrations from opening to closing of the suction valve, and increases the maximum displacement of the suction valve. By doing so, the suction amount of the refrigerant gas is maximized. Further, the reverse flow rate of the refrigerant gas from the cylinder to the suction hole side during the compression stroke can be suppressed to a minimum, so that the effect of improving the refrigerating capacity and efficiency can be obtained.

According to a fourth aspect of the present invention, a piston, a cylinder, a cylinder head, a valve plate having a plurality of suction holes, a switching valve for switching a plurality of suction holes, and a switching valve are provided. It comprises an electromagnet to be driven, a suction valve having a plurality of movable parts installed between a valve plate and a cylinder, and a valve opening / closing control device that detects an operating frequency and energizes the electromagnet,
A plurality of intake valves are configured, and by using a valve opening / closing control mechanism provided on a valve plate so that the intake valve can be selected according to a plurality of specific operation frequencies such as an inverter operation, a plurality of intake frequencies can be set. Corresponding refrigeration capacity and efficiency improvement effects can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a compression unit of a hermetic compressor according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a main part of the suction valve and the valve plate when the suction valve of the hermetic compressor of the embodiment is opened and closed.

FIG. 3 is a sectional view of a main part of a compression unit of a second embodiment of the open / close type compressor according to the present invention;

FIG. 4 is a cross-sectional view of main parts of the suction valve, the valve plate, and the piston when the suction valve of the hermetic compressor of the embodiment is opened.

FIG. 5 is a sectional view of a main part of a compression unit when a suction valve is closed according to a third embodiment of the hermetic compressor according to the present invention;

FIG. 6 is a sectional view of a main part of the compression unit when the suction valve of the hermetic compressor of the embodiment is open.

FIG. 7 is a characteristic diagram showing displacement amounts of a suction valve and a piston with respect to a crank angle of the hermetic compressor of the embodiment.

FIG. 8 is a sectional view of a main part of a compression unit of a hermetic compressor according to a fourth embodiment of the present invention.

FIG. 9 is a front view of a suction valve of the hermetic compressor of the embodiment.

FIG. 10 is a front view of a valve plate of the hermetic compressor of the embodiment.

FIG. 11 is a flowchart showing the operation of the control device for the hermetic compressor of the embodiment.

FIG. 12 is a longitudinal sectional view of a conventional compressor.

FIG. 13 is a sectional view of a main part of a compression unit of a conventional compressor.

FIG. 14 is a sectional view of a main part of a suction valve and a valve plate of a conventional compressor.

FIG. 15 is a front view of a suction valve of a conventional compressor viewed from a cylinder head side.

FIG. 16 is a front view of a valve plate of a conventional compressor viewed from a cylinder head side.

[Explanation of symbols]

 Reference Signs List 4 cylinder head 6 cylinder 7, 25 piston 9, 33 suction hole 22 valve seat groove 23, 27, 28, 32 suction valve 23a curved portion 24, 31 valve plate 26 buffer material 29, 35 electromagnet 30 conductive control device 32a movable portion 34 Switching valve 36 Valve open / close control device

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akio Yagi 4-2-2-5 Takaida Hondori, Higashiosaka-shi, Osaka Matsushita Refrigeration Machinery Co., Ltd. F-term (reference) 3H003 AA02 AB04 AC03 CC04 CC11

Claims (4)

[Claims] A valve plate provided with a piston, a cylinder, a cylinder head, a suction hole, a valve seat groove formed around the suction hole on the cylinder side of the valve plate, the valve plate and the valve plate; A hermetic compressor comprising a suction valve disposed between cylinders, wherein the suction valve has a curved portion in which a tip of the suction valve is convex toward the cylinder. 2. A piston, a cylinder, a cushioning member provided on an end face of the piston, a cylinder head,
A hermetic compressor comprising a valve plate and a suction valve installed between the valve plate and the cylinder. 3. A piston, a cylinder, a cylinder head, a valve plate, a suction valve installed between the valve plate and the cylinder, an electromagnet provided near a top dead center of the cylinder, An energization control device for detecting the behavior of a piston and energizing the electromagnet. 4. A valve plate having a piston, a cylinder, a cylinder head, a plurality of suction holes, a switching valve for switching between the plurality of suction holes, an electromagnet for driving the switching valve, and the valve. A hermetic compressor comprising: a suction valve having a plurality of movable parts disposed between a plate and the cylinder; and a valve opening / closing control device for detecting an operation frequency and supplying electricity to the electromagnet.