JPH0121188Y2 - - Google Patents

Description

[Detailed description of the invention] [Purpose of the invention] (Field of industrial application) The present invention relates to a reciprocating compressor used in the refrigeration cycle of an air conditioner, etc. Regarding the improvement of the internal structure of.

(Prior Art) It is known that compressors used in refrigeration cycles such as air conditioners include rotary type compressors and reciprocating type compressors. Furthermore, recently, the refrigeration cycle is provided with an injection circuit in order to improve air conditioning efficiency.

In this circuit, as shown in FIG. 6, the refrigerant discharged from the compressor 20 is guided to the pseudo-condenser 21 for heat exchange, and then transferred from the gas-liquid separator 22 to the injection extraction circuit 23 to complete the compression stroke of the compressor 20. It is designed to inject into the cylinder chamber inside. In addition, 2
4 is a pressure reducing device, and 25 is an evaporator.

However, the rotary type has a relatively simple structure and can easily perform the injection action, but the reciprocating type has the compression and suction strokes performed alternately during one reciprocation of the piston, so the injection action cannot be compressed. In order to operate only during the process, a complicated structure as shown in FIG. 7 was required.

A piston 28 is reciprocatably housed inside a cylinder wall 27 forming a cylinder 26 in FIG. A valve seat 31 equipped with a suction valve 29 and a discharge valve 30 is provided on the upper surface of the cylinder 26.
is placed on the upper surface of the cylinder 26, and further above the valve cover 36, which forms a suction chamber 33 communicating with the suction pipe 32 and a discharge chamber 35 communicating with the discharge pipe 34, is arranged.

The injection mechanism of this reciprocating compressor supplies the refrigerant from the gas-liquid separator to the piston 2 through the refrigerant supply hole 37 formed in the cylinder wall 27.
The liquid refrigerant filled in the communication hole 38 is then injected into the cylinder through a refrigerant injection hole 39 formed in the cylinder wall 27.

However, the injection mechanism of such a reciprocating compressor has a complicated structure;
High precision is also required for the communication process between the communication hole 38, refrigerant supply hole 37, and refrigerant injection hole 39, and if the positions of the holes are misaligned, the injection timing cannot be adjusted, which may affect the reliability of the compressor. There was a problem.

(Problem to be solved by the invention) This invention was made in view of the above circumstances.
The object of the present invention is to provide a reciprocating compressor having a simple structure and a highly reliable injection mechanism.

[Structure of the idea]

(Means for Solving the Problems) In other words, in order to achieve the above object, the present invention provides a cylinder liner having a cylinder chamber, a valve seat provided at the upper end of this cylinder liner, this valve seat and the above-mentioned cylinder liner. a recess configured with a cylinder liner, a suction valve displaceably housed in the recess, a suction hole provided in the valve seat and opened and closed by the suction valve, and a suction hole provided in the cylinder liner to be compressed. an injection passage for injecting a part of machine fluid into a cylinder chamber during a compression stroke, and an opening on the cylinder chamber side of the injection passage is provided in the recess at a position opposite to the suction hole with the suction valve in between. We provide compressors that are

(Function) According to such a configuration, the suction valve contacts the valve seat surface so as to close the suction hole due to the discharge pressure, and the recessed portion of the cylinder liner so as to close the opening of the injection passage passage due to the suction pressure. The injection action is performed only during the compression stroke.

(Example) An example of the present invention will be described below based on the drawings. In FIG. 1, 1 is a cylinder liner which is the main part of the compressor. A valve cover 2 is provided at the upper end of the cylinder liner 1 . A valve seat 5 having a suction hole 3 and a discharge hole 4 is supported inside the valve cover 2 .

The suction hole 3 is opened and closed by a suction valve 6, which will be described later, and the discharge hole 4 is opened and closed by a discharge valve 7. This discharge valve 7 is pressed 8
As a result, the discharge hole 4 is elastically pressed and urged to close. A cylinder chamber 9 is provided inside the cylinder liner 1, and a piston 10 connected to a crankshaft (not shown) is reciprocatably housed therein.

The suction valve 6, as shown in FIG. 2, is a ring-shaped plate valve, and protrusions 6a, 6a are integrally provided at symmetrical positions on the outer circumference. A suction valve retainer 11 is positioned around the outer periphery of the suction valve 6 with a narrow gap therebetween to prevent the suction valve 6 from shifting.

As shown in FIG. 1, the suction valve 6 formed in this manner includes a suction valve retainer 11, a cylinder liner 1, and a valve cover 2 provided at its upper end.
It is housed in a recess 12 formed by.

Further, an opening 13 is provided on the cylinder liner 1 side of the recess 12, and an injection passage 14 that is diagonally bored from a part of the outer circumferential wall of the cylinder liner 1 communicates with the opening 13. A check valve 15 is provided in the injection passage 14, and communicates with an injection extraction circuit 16 of the refrigeration cycle.

As the piston 10 reciprocates, the suction valve 6 and the discharge valve 7 alternately open and close the suction hole 3 and the protrusion hole 4, respectively. Therefore, refrigerant gas is sucked into the cylinder chamber 9, compressed, and then discharged. In addition, the suction valve 6 closes the suction hole 3 during the compression stroke, as shown in FIG.
A gap 8 is formed between the opening 13 of 2 and the gap 8 is opened. At this time, the internal pressure Po of the cylinder chamber 9 is smaller than the injection pressure Pi, and therefore, the refrigerant is injected into the cylinder chamber 9 via the injection passage. Note that even during the compression stroke, when Po>Pi, the refrigerant in the cylinder chamber 9 leaks into the injection passage 14, but this is prevented by the check valve 15. Furthermore, as shown in FIG. 3B, during the suction stroke, the suction valve 6
The protruding portion 6 a closes the opening 13 while opening the suction hole 3 by contacting the two surfaces. Since the area of the opening 13 is extremely small compared to the area of the suction hole 3, the force of pushing up the suction valve 6 due to the injection pressure Pi is ignored without any influence.
That is, during the suction stroke, the injection passage 14 is closed by the suction valve 6. In this way, the suction valve 6 in the suction stroke and the compression stroke
By this displacement, the injection passageway 14 is reliably opened and closed.

In the above embodiment, the suction valve 6 was explained as a simple plate valve, but it is not limited to this. For example, as shown in FIG.
A hemispherical seal ball 17 may be provided protrudingly at a position facing 3. This seal ball 17 is not required at all during the injection stroke during the compression stroke shown in FIG. 5A, but the seal ball 17 fits into the opening 13 during the suction stroke shown in FIG. 5B.

At this time, the suction valve 6 comes into contact with the recess 12 and is bent and deformed as shown in the figure, so that the suction valve 6 does not contact the recess 12 uniformly. However, the seal ball 17 closes the opening 13 and no leakage of refrigerant from the injection passage 14 to the cylinder chamber 9 occurs. (Except for the injection ball 17, the shape is slightly different from that of the above embodiment, but since the function is completely the same, the same number will be assigned and the explanation will be omitted.) [Effect of the invention] As explained above, this invention According to the idea, although it is a reciprocating type compressor, it does not require complicated processing and can obtain reliable and reliable injection action with a very simple structure, which has a negative impact on processing costs. This has the effect of improving compression efficiency without causing any damage.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view of the main parts of a compressor showing an embodiment of the present invention, Fig. 2 is a plan view of the suction valve, Figs. 3 A and B are explanatory diagrams of the suction valve in different states, and Fig. 4
The figure is a vertical cross-sectional view of the main parts of a compressor showing another embodiment of the present invention, Figures 5A and B are explanatory diagrams of different states of the suction valve, and Figure 6 is a refrigeration cycle showing the connection state of the injection and extraction circuit. 7 are longitudinal sectional views of the main parts of a conventional compressor. 1... Cylinder liner, 3... Suction hole, 5...
Valve seat, 6... Suction valve, 9... Cylinder chamber, 12... Recess, 13... Opening, 14... Injection passage.

Claims (1)

[Scope of utility model registration request] A cylinder liner having a cylinder chamber, a valve seat provided at the upper end of the cylinder liner, a recess formed by the valve seat and the cylinder liner, and a suction valve displaceably housed in the recess. , comprising a suction hole provided in the valve seat and opened and closed by the suction valve, and an injection passage provided in the cylinder liner for injecting a part of the fluid to be compressed into a cylinder undergoing a compression stroke; A compressor characterized in that an opening on the cylinder chamber side is provided in the recess at a position opposite to the suction hole with the suction valve in between.