KR19980026399A - Compressor Unloading Valve - Google Patents

Abstract

The present invention discloses an improved unloading valve of a compressor for driving an air conditioner.

Conventionally, since the unloading valve is normally closed, at the time of short circuit, the air conditioner can only be driven at half the capacity of the compressor.

In the present invention, the piston for opening and closing the refrigerant inlet hole of the crankcase, the body movably coupled to the inside of the liner, and the head and body and the head extending from the bottom of the body to close the bottom of the liner by contacting from the outside The neck is formed in a predetermined length and has a neck having an outer diameter smaller than the inner diameter of the liner. The unloading valve is normally opened so that the air conditioner can be driven with the full capacity of the compressor even during a short circuit.

Description

Compressor Unloading Valve

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to air conditioners, and more particularly, to an unloading valve that regulates the amount of refrigerant flowing into a compressor.

An air conditioner that cools the room using a cooling cycle liquefies a refrigerant gas compressed at a high pressure in a compressor in a condenser and then in an evaporator through an expansion valve. As an air conditioner that performs cooling by vaporization heat of a refrigerant by vaporizing, it is widely used throughout society.

For example, even in automobiles, it is used for comfortable environment in summer. Passenger cars have a relatively small space to cool, and a small cooling system is enough, but a bus has a lot of space to cool down. Therefore, a large cooling system is adopted. As a result, a bus air conditioner also requires a large capacity compressor for driving the cooling cycle. A multi-cylinder compressor is generally used.

On the other hand, the air conditioner is equipped with a temperature control device for properly controlling the temperature of the room, the temperature control method is to turn on the clutch of the compressor based on the room temperature at the time according to the selected temperature of the temperature controller provided in the air conditioner The method of controlling the drive of a compressor by turning it ON / OFF is mainly used.

However, the temperature control method is not smooth in the temperature control operation, the pressure pulsation of the refrigerant is severe, not only reduce the durability of the refrigerant moving pipe, etc., but also momentarily overload the engine (engin) that drives the driving performance and This will adversely affect the durability of the engine.

Accordingly, in recent years, the compressor is always driven, and by appropriately adjusting the amount of refrigerant introduced therein, for example, in the case of a four-cylinder compressor, for example, two cylinders selectively drive two cylinders according to a selected temperature. The driving method to control the cooling performance of the has emerged.

Figure 1 schematically shows an example of a conventional unloading valve for this. This means that if no power is applied to the coil 6, the plunger 7 is elastically biased downward by the spring 8 to bypass the flow path 1b of the valve body 1b. ) Will be closed. Accordingly, the high pressure portion (H) of the crank case (C) acts on the piston (3) through the operating flow path (1a) of the valve body (1), so that the piston (3) is a liner (2). Move downward to close the refrigerant inlet hole (R) of the crankcase (C). Then, the compressor is always closed because the two cylinders do not flow the refrigerant outputs only half of the total capacity. In this state, when power is applied to the coil 6 of the unloading valve, the magnetic force thereof causes the plunger 7 to rise while compressing the spring 8 to open the bypass passage 1b of the valve body 1. do. Then, the high pressure portion of the crankcase C is discharged to the low pressure portion L through the bypass passage 1b, whereby the piston 3 is moved to the upper portion of the liner 2 by the compression spring 4. By returning, the refrigerant inlet hole R of the crankcase C is opened. Thus, the refrigerant flows through all the cylinders of the compressor, so the compressor outputs all of its capacity. The remaining symbols P1 and P2 are the high and low pressure flow paths of the crankcase C, and 5 is the coil housing.

However, since the conventional unloading valve is always closed, it is necessary to turn on the power to the coil 6 to open the piston 3 when the full capacity is used, so that the coil 6 is normally operated in the air conditioner. Power should always be applied to the piston, and only closes the piston (3) selectively when excessive cooling. Accordingly, the power consumption is excessive, the risk of short circuit of the coil (6) is very high, in this case there is a problem that the cooling efficiency is lowered because only the capacity of half of the compressor can drive the air conditioner. Therefore, the conventional unloading valve could not guarantee the stability and reliability of the operation of the air conditioner.

Disclosure of Invention An object of the present invention is to provide an unloading valve of a compressor capable of stably driving an air conditioner at a full capacity of a compressor without significantly affecting a short circuit of a coil in view of the above-described conventional problems and greatly reducing power consumption. .

In order to achieve the above object, an unloading valve of a compressor according to the present invention includes a liner having a coolant flow path hole coaxially installed between the high pressure portion and the low pressure portion of the crankcase and having a coolant flow path hole on the main surface thereof, A valve body having a piston capable of being coupled and elastically biased to the open side of the refrigerant inlet hole, a working flow path fixed to the crankcase and guiding the high pressure part into the liner, and a bypass flow path leading the high pressure part to the low pressure part; The compressor is mounted on the main body and includes a housing in which a coil is selectively applied, and an elastic biased to close the bypass flow path in the housing, and a plunger selectively opening the bypass flow path by the magnetic force of the coil. In the loading valve, the piston is movably coupled to the inside of the liner Is a neck extending from the bottom of the body and having a head for contacting and closing the bottom of the liner from the outside thereof, and a neck having a predetermined length between the body and the head and having an outer diameter smaller than the inner diameter of the liner. Characterized in that consists of.

According to one preferred feature of the present invention, the lower surface of the body and the upper surface of the head are configured to be inclined by a predetermined angle, respectively, to form an approximately V-shape with each other.

In the present invention, the piston selectively shuts off the refrigerant inlet of the crankcase at all times, thereby allowing the compressor to drive the air conditioner at a full capacity regardless of the short circuit of the coil. It will have a great effect on reliability improvement.

1 is a cross-sectional view showing a conventional unloading valve,

Figure 2 is an open state cross-sectional view showing an unloading valve according to the present invention,

3 is a closed cross-sectional view thereof.

* Description of the symbols for the main parts of the drawings *

11: valve body 11a: operating flow path (of valve body)

11b: Bypass Euro (of valve body)

15: liner 16: flange (of liner)

17: piston 18: body

19: (piston) head 20: (piston) neck

21 guide 22 cover plate

23: compression spring 25: coil

26: plunger

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 and 3, the unloading valve of the compressor according to the present invention is provided in the refrigerant passage through which the refrigerant flows into the compressor, for example, between the high pressure portion (H) and the low pressure portion (L) of the crankcase (C). The liner 15 communicating with the coolant inlet R is coaxially installed in the coolant channel S of the same. A plurality of flow path holes 15a communicating with the refrigerant flow path S of the crankcase C are formed at the main surface of the liner 15, preferably at a position biased toward the refrigerant inflow hole R side.

The outer surface of the crankcase (C) is provided with a valve body 11, which preferably consists of the upper and lower bodies 13, 12 coupled to each other. On the outer surface of the lower body 12, a support bolt 14 positioned inside the liner 15 extends to an appropriate length, and a cylindrical guide 21 is screwed to the support bolt 14.

Inside the liner 15, a refrigerant inlet hole R of the crankcase C, that is, a piston 17 that opens and closes the lower end of the liner 15 is movably inserted. The piston 17 has a cylinder-shaped body 18 movably inserted into the liner 15 in accordance with a feature of the present invention, and extends from the bottom of the body 18 to the bottom of the liner 15. It consists of a head 19 in contact with the outside and the neck 20 connecting the head 19 and the body 18. Thus, in order for the head 19 of the piston 17 to contact the lower end of the liner 15 from the outside, the diameter of the head 19 may be configured to be larger than the inner diameter of the liner 15, but preferably the piston 17 The diameter of the head 19 of the c) is the same as that of the body 18, and the flange 19 protrudes at an appropriate height on the inner circumference of the lower end of the liner 15.

The neck 20 of the piston 17 is configured to have an outer diameter smaller than the inner diameter of the flange 16 of the liner 15 so that the refrigerant can flow, the difference in diameter is appropriately set in consideration of the smooth flow of the refrigerant. In addition, the lower surface of the body 18 and the upper surface of the head 19 of the piston 17 is also preferably configured to be inclined at an appropriate angle to form a substantially V-shape each other as shown for smooth flow of the refrigerant.

On the other hand, a cover plate 22 defining a stroke of the piston 17 is provided at the open upper end of the body of the piston 17, and the cover plate 22 and the guide are provided. A compression spring 23 is interposed between the flanges 21a of the 21 to elastically bias the piston 17 to the upper side of the liner 15 so as to close the refrigerant inlet hole R. As shown in FIG. To this end, the outer periphery of the guide 21 is formed to be stepped as much as the stroke of the cover plate 22, preferably the stroke is the lower surface of the body 18 in the state where the piston 17 is lowered to the lowermost liner 15 It is set in the range which does not contact on the flange 16 of ().

On the other hand, the lower body 12 of the valve body 11 communicates with the working flow passage 11a for inducing high pressure of the crankcase C to the inside of the liner 15 and the working flow passage 11a and the crankcase C. A bypass flow path 11b is formed to guide the high pressure of the lower pressure part L, and a slot communicating with each of the flow paths 11a and 11b of the lower body 12 is formed at the center of the upper body 13. : 13a) is formed.

On the upper body 13 of the valve body 11 is installed a coil housing 24 incorporating a coil 25 to which power is selectively supplied, and a slot of the upper body 13 in the center of the coil housing 24. A plunger 26 for selectively opening and closing the bypass passage 11b through 13a is movably installed and elastically biased to close the bypass passage 11b by the spring 27. The remaining symbols P1 and P2 are the high and low pressure flow paths of the crankcase C.

Looking at the operation of the unloading valve of the compressor according to the present invention configured as described above are as follows.

In the unloading valve of the present invention, power is not applied to the coil 25 during the normal driving of the air conditioner. Accordingly, as shown in FIG. 2, the plunger 26 is elastically biased downward by the spring 27 so that the bypass flow path 11b of the valve body 11 is always at the high pressure part H of the crankcase C. Will be blocked. Therefore, the pressure of the high pressure portion (H) is the inside of the liner 15, that is, the cover plate 22 of the piston 17 through the high pressure flow path P1 of the crankcase C and the working flow path 11a of the valve body 11. By acting only on), the piston 17 is pushed downward by the stroke.

Then, the head 19 of the piston 17 is dropped from the lower end of the liner 15, and the neck 20 is positioned at the flange 16 of the liner 15 so that the refrigerant flows into the crankcase C. After flowing into the liner 15 through the hole R, the refrigerant flows into the refrigerant path S through the flow path hole 15a thereof. Therefore, during normal operation of the air conditioner, the compressor drives the air conditioner at the full capacity, so that even if a short circuit occurs in the unloading valve, the air conditioner can be stably driven at the full capacity without a decrease in the capacity of the conventional compressor.

On the other hand, when adjusting the temperature of the room according to the selected temperature of the temperature controller as shown in Figure 3 power is applied to the coil 25, according to the magnetic force of the coil 25 is the plunger 26 spring 27 ) Is moved upward while compressing. Then, the bypass passage 11b of the valve body 11 is opened to communicate with the high pressure passage P1 of the crankcase C, whereby the high pressure in the crankcase C is bypassed by the valve body 11. Through the flow path 11b and the low pressure flow path P2, the low pressure part L exits.

Therefore, the high pressure of the crankcase C is not applied to the inside of the liner 15 so that the piston 17 is returned to the upper portion of the liner 15 by the compression spring 23. Then, the head 19 of the piston 17 moves upward to close the lower end of the liner 15 to close the refrigerant passage S. Accordingly, the compressor controls the temperature of the room by driving the air conditioner with only half its capacity.

As described above, according to the present invention, since the unloading valve is always open, the air conditioner can be driven at a full capacity without a decrease in the capacity of the compressor as in the case of the short circuit. In addition, during normal driving, power is not applied to the coil, but only when the room temperature is adjusted according to the selected temperature of the temperature controller. Therefore, power consumption is minimized to extend the life of the battery as much as possible.

Therefore, the present invention has a very excellent effect of greatly improving the cooling efficiency and stability and reliability of the air conditioner, as well as the reliability of the automobile employing the same.

Claims (2)

A liner disposed coaxially with the refrigerant inlet hole between the high pressure portion and the low pressure portion of the crankcase and having a refrigerant passage hole on a main surface thereof, a piston movably coupled in the liner to elastically bias toward the open side of the refrigerant inlet hole, and A housing having a valve body fixed to the crankcase and having a working flow path leading the high pressure part into the liner and a bypass flow path leading the high pressure part to the low pressure part, and a coil installed on the valve body and selectively supplied with power. And a plunger elastically biased to close the bypass flow passage in the housing and selectively opening the bypass flow passage by a magnetic force of the coil, wherein the unloading valve of the compressor comprises: The piston 17 is A body 18 movably coupled to the inside of the liner 15, A head 19 extending from the lower end of the body 18 and closing the lower end of the liner 15 in contact with the outside thereof; The unloading valve of the compressor, characterized in that the neck (18) formed of a predetermined length between the body (18) and the head (19) having an outer diameter smaller than the inner diameter of the liner (15). The method of claim 1, The unloading valve of the compressor, characterized in that the lower surface of the body (18) and the upper surface of the head (19) are configured to be inclined by a predetermined angle, respectively, so as to form a substantially V-shape each other.