KR101984509B1 - Device for measuring amount of refrigerant flow in compressor - Google Patents

Abstract

It is possible to detect the discharge flow rate more accurately from the detection of the magnetic flux density for the spool valve which changes in accordance with the discharge flow rate of the refrigerant in the bypass path and the bypass flow branched from the main discharge path of the compressor refrigerant, Disclosed is a refrigerant discharge flow rate measuring device for a compressor capable of controlling an intermediate torque in an optimum state and thereby minimizing a loss of unnecessary driving force.
The refrigerant discharge flow rate measuring apparatus described above includes a main discharge passage 300 communicating with the discharge chamber 262 of the compressor 100 and a main discharge passage 300 branched from the main discharge passage 300 and joined to the main discharge passage 300. [ A spool valve 330 for variably controlling the displacement according to the flow rate of the refrigerant installed and bypassed in the chamber 320; A magnetic body 340 provided on the spool valve 330 and a magnetic sensor 350 for detecting a change in the magnetic flux density which is accompanied by the displacement of the magnetic body 340.

Description

Technical Field [0001] The present invention relates to a device for measuring a refrigerant flow in a compressor,

[0001] The present invention relates to a refrigerant discharge flow rate measuring apparatus for a compressor, and more particularly, to a refrigerant discharge flow rate measuring apparatus for a compressor, which comprises a bypass path branching from a main discharge path of a compressor refrigerant, And more particularly, to a refrigerant discharge flow rate measuring device for a compressor capable of contributing to minimizing loss of unnecessary driving force by controlling an optimal state.

2. Description of the Related Art Generally, compressors for compressing refrigerant in a vehicle cooling system have been developed in various forms. In such compressors, there are a reciprocating type in which a refrigerant is compressed and a reciprocating type in which a refrigerant is compressed, There is a rotary type.

The reciprocating compressor includes a crank type in which a driving force of a drive source is transmitted to a plurality of pistons using a crank, a swash plate type in which the swash plate is transmitted through a swash plate rotary shaft, and a wobble plate type in which a wobble plate is used. A vane rotary type using a rotary shaft and a vane, and a scroll type using a revolving scroll and a fixed scroll.

On the other hand, as the swash plate type compressor, there are a fixed displacement type in which the installation angle of the swash plate is fixed and a variable displacement type in which the discharge displacement can be changed by changing the inclination angle of the swash plate.

FIG. 1 shows the construction of a general variable capacity swash plate type compressor. Hereinafter, a schematic configuration of the variable displacement swash plate type compressor will be described with reference to FIG.

A variable capacity swash plate type compressor 10 is provided with a cylinder block 20 forming a part of an outer appearance and a skeleton of the compressor 10. At this time, a center bore 21 is formed through the center of the cylinder block 20, and a rotation shaft 60 is rotatably installed in the center bore 21. [

A plurality of cylinder bores 22 are formed through the cylinder block 20 so as to radially surround the center bore 21. A piston 70 is installed in the cylinder bore 22 so as to reciprocate linearly. At this time, the piston 70 is formed in a cylindrical shape, and the cylinder bore 22 is a cylindrical space corresponding to the cylinder bore 22. The refrigerant in the cylinder bore 22 is compressed by the reciprocating motion of the piston 70.

The front housing 30 is coupled to the front of the cylinder block 20. The front housing 30 faces the cylinder block 20 to form a crank chamber 31 together with the cylinder block 20. [

A pulley 32 connected to an external power source such as an engine is rotatably mounted on the front of the front housing 30 so that the rotary shaft 60 rotates in conjunction with the rotation of the pulley 32.

A rear housing (40) is coupled to the rear of the cylinder block (20). A discharge chamber 41 is formed in the rear housing 40 along a position adjacent to the outer circumferential edge of the rear housing 40 so as to selectively communicate with the cylinder bore 22. The discharge chamber 41 is formed in a radial direction of the discharge chamber 41 A suction chamber 42 is formed at the center of the rear housing 40.

A valve plate 50 is interposed between the cylinder block 20 and the rear housing 40 and the discharge chamber 41 is connected to the cylinder bore 22 through the discharge port 51 formed in the valve plate 50. [ And the suction chamber 42 communicates with the cylinder bore 22 through the suction port 52 of the valve plate 50. [

The swash plate 61 is provided on the rotary shaft 60. The swash plate 61 is connected to the respective pistons 70 by a shoe 62 provided along the rim of the swash plate 61. By the rotation of the swash plate 61, (70) reciprocates linearly in the cylinder bore (22).

The angle of the swash plate 61 relative to the rotary shaft 60 is variable so that the refrigerant discharge amount of the compressor 10 can be adjusted. To this end, the discharge chamber 41 and the crank chamber 31 are communicated with each other Is controlled by a pressure control valve (not shown).

On the other hand, in the case of the variable displacement swash plate type compressor, since the compression load variation of the compressor is related to the engine load fluctuation, it is necessary to detect the torque fluctuation of the compressor and to control the engine speed in consideration of the detection torque fluctuation. Fig. 2 shows a flow rate detecting apparatus disclosed in Japanese Patent Laid-Open No. 2007-303416 (Patent Document 1) for detecting the torque fluctuation of the compressor.

The flow rate detecting device shown in Fig. 2 is provided in a discharge flange 2 serving as a flange member joined to the outside of the cylinder block 1, and includes a movable portion 3 accommodated in the discharge flange 2, A coil spring 4 for resiliently supporting the movable body 3 and a magnetic sensor 5 as a detection sensor fixed to the surface of the discharge flange 2. The coil spring 4 has a body 3,

At this time, in the process of moving the movable body 3 up and down by the pressure difference between the high pressure chamber 6a and the low pressure chamber 6b, the magnetic flux density change of the magnet 3a is detected by the magnetic sensor 5, It is to be appreciated that the amplifier 7 which receives the detection value from the magnetic sensor 5 via the connection line 7a calculates the discharge capacity of the compressor on the basis of the flow rate data and performs the feedback control of the pressure regulating valve, As shown in FIG.

However, in the conventional flow rate detecting device as described above, since a separate throttling portion must be formed between the high-pressure chamber 6a and the low-pressure chamber 6b for installing the movable body, the pressure loss is accompanied thereby, There is a problem in that the accuracy of the measured value is low at a low flow rate when the throttle portion is of a fixed size.

Further, since the flow rate detecting apparatus of the conventional compressor is a system for estimating the discharge flow rate through the differential pressure detected between the high-pressure chamber 6a and the low-pressure chamber 6b, the level of the differential pressure detected when the discharge flow rate is small is also low The measurement of the flow rate can not be performed. Particularly, since the flow rate detecting apparatus of the conventional compressor calculates the discharge flow rate of the refrigerant by the differential pressure which is a pressure difference before and after the movable body 3, it is essential to ideally maintain the differential pressure before and after the function of the movable body 3, The leakage of the refrigerant gas between the movable body 3 and the surrounding portion of the movable body 3 is inevitably caused due to the structure in which the movable body 3 is moved according to the degree of the differential pressure generated by the flow of the refrigerant gas, This results in a failure to measure the exact flow rate.

Patent Document 1: Japanese Unexamined Patent Application Publication No. 2007-303416 (published on November 22, 2007)

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a refrigeration system for a refrigeration cycle, The present invention provides a refrigerant discharge flow rate measuring device for a compressor which can control the torque of the compressor in an optimum state by minimizing the loss of unnecessary driving force by enabling more accurate detection of the discharge flow rate .

According to another aspect of the present invention, there is provided a measuring apparatus for detecting a flow rate of a refrigerant discharged to the outside through a discharge chamber of a compressor, the apparatus comprising: a main discharge passage communicating with the discharge chamber; A bypass passage formed to join with the main discharge passage, a chamber formed in the bypass passage, a spool valve for variably controlling a displacement in accordance with a flow rate of a refrigerant installed and bypassed in the chamber, And a magnetic sensor for detecting a change in the magnetic flux density which is accompanied by the displacement of the magnetic body.

In the present invention, the bypass passage includes an inlet of a bypass passage formed to introduce refrigerant into the chamber, and an outlet of a bypass passage formed to discharge the refrigerant from the inside of the chamber to the main discharge passage Respectively.

In the spool valve according to the present invention, the spool valve may be a non-magnetic material, and may include a first land that always keeps the inlet of the bypass passage in an open state, and a second land that keeps the opening of the bypass passage at a position spaced from the first land, A second land for adjusting the operation of the compressor in conjunction with operation of the compressor, and a groove for allowing the flow of the refrigerant between the first land and the second land.

In the present invention, the hydraulic pressure area of the first land is set to be smaller than the hydraulic pressure area of the second land.

In the present invention, the spool valve may further include a first return spring for providing an elastic force so as to close the outlet of the bypass passage at the time of the ratio of the compressor, and the first return spring, So as to press the free end portion of the first land in the direction toward the first land.

In the present invention, the spool valve may include a first return spring that provides an elastic force so as to close the outlet of the bypass passage at the same time as the ratio of the compressor is closed, and a second return spring that urges the outlet of the bypass passage Wherein the first return spring is installed to urge the free end of the second land in the chamber toward the first land, and the second return spring is arranged to press the free land of the second land toward the first land, Wherein the resilient force of the first return spring and the second return spring is such that the elastic force of the first return spring and the second return spring causes the opening of the bypass passage to open And the spool valve is set to a position for closing the outlet of the bypass passage.

According to the present invention, the chamber is provided with a drain hole communicable with the outside from at least one of the first land and the second land so as to discharge the refrigerant leaked, and the refrigerant leaking through the drain hole And is set to communicate with the suction chamber of the compressor.

In the present invention, the magnetic body is installed in the groove of the spool valve. Further, the magnetic body is installed in the first land and the second land of the spool valve, respectively. Further, the magnetic sensor is installed at a position covering the entire displacement section of the magnetic body at the side of the chamber.

The apparatus for measuring the refrigerant discharge flow rate of the compressor according to the present invention is provided with a bypass path branched from the main discharge path of the refrigerant and reconnected to the main discharge path, It is possible to more precisely measure the discharge flow rate by detecting a change in the magnetic flux density from the displacement of the spool valve which varies depending on the degree of the displacement of the spool valve. Therefore, the torque required for the operation of the compressor can be controlled in an optimal state, It is possible to minimize the unnecessary loss of the driving force required for operation and to improve the energy consumption efficiency.

That is, according to the present invention, a chamber for permitting installation and displacement of a spool valve is formed in a bypass path branching from a main discharge path of a compressor refrigerant and reconnected, It is possible to precisely calculate the total discharge flow rate of the refrigerant by measuring the magnetic flux density from the displacement. Therefore, unnecessary loss of the driving force can be prevented by optimally controlling the torque required for operating the compressor, and energy efficiency can be improved.

In particular, since the present invention eliminates the need for forming a throttle portion in comparison with a refrigerant flow rate measuring apparatus of the conventional compressor, it is easy to manufacture equipment, and in particular, when the differential pressure between the high- It is possible to solve the problem that the accurate measurement of the flow rate can not be performed and to solve the problem of the leakage accompanying the displacement at the region where the flow rate of the refrigerant is measured.

1 is a cross-sectional view schematically showing the overall configuration of a general variable capacity swash plate type compressor.
2 is a diagram showing a configuration of an apparatus for detecting a discharge flow rate of a conventional compressor.
3 is a cross-sectional view schematically showing the overall configuration of a compressor equipped with a refrigerant discharge flow rate measuring apparatus according to an embodiment of the present invention.
FIG. 4 is an enlarged view of only the configuration of the refrigerant discharge flow rate measuring apparatus shown in FIG. 3, and shows the state of the compressor at the same time.
FIG. 5 is an enlarged view of only the configuration of the refrigerant discharge flow rate measuring apparatus shown in FIG. 3, and shows a state when the compressor is in operation.
FIG. 6 and FIG. 7 are views showing a discharge flow rate measuring apparatus for a refrigerant according to another embodiment of the present invention, wherein FIG. 6 shows a non-moving state of the compressor and FIG. 7 shows a moving state of the compressor, respectively.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, preferred embodiments of a refrigerant discharge flow rate measuring apparatus for a compressor according to the present invention will be described in detail with reference to the accompanying drawings. In this process, the thicknesses of the lines and the sizes of the components shown in the drawings may be exaggerated for clarity and convenience of explanation.

Further, the terms to be described below are defined in consideration of the functions of the present invention, which may vary according to the intention or custom of the user, the operator. Therefore, definitions of these terms should be made based on the contents throughout this specification.

In addition, the following embodiments are not intended to limit the scope of the present invention, but merely as exemplifications of the constituent elements set forth in the claims of the present invention, and are included in technical ideas throughout the specification of the present invention, Embodiments that include components replaceable as equivalents in the elements may be included within the scope of the present invention.

Example

The apparatus for measuring a refrigerant discharge flow rate of a compressor according to an embodiment of the present invention includes a fixed capacity type in which the installation angle of the swash plate is fixed and a variable capacity type in which the discharge capacity can be changed by changing the inclination angle of the swash plate, The present invention is applied to a variable displacement swash plate type compressor.

3 is a cross-sectional view schematically showing the overall configuration of a compressor equipped with a refrigerant discharge flow rate measuring apparatus according to an embodiment of the present invention. 3, a swash plate type compressor 100 according to an embodiment of the present invention includes a cylinder block 120 forming a part of an outer appearance and a skeleton of the compressor 100, A center bore 122 formed through the center of the cylinder block 120, a rotation shaft 140 rotatably installed on a central portion of the center bore 122, A plurality of cylinder bores 160 disposed in the cylinder bore 160 and a piston 180 installed in the cylinder bore 160 so as to reciprocate linearly in the cylinder bore 160; And a swash plate 200 for providing a moving force of the swash plate 200.

The front housing 220 is coupled to the front portion of the cylinder block 120. The front housing 220 faces the cylinder block 120 to form a crank chamber 222 together with the cylinder block 120. A pulley 240 connected to an external power source (not shown) such as an engine is rotatably installed at the front of the front housing 220 and the rotation shaft 140 rotates in conjunction with rotation of the pulley 240 .

The rear housing 260 is coupled to the rear portion of the cylinder block 120. The rear housing 260 is formed with a discharge chamber 262 along a position adjacent to the outer circumferential edge of the rear housing 260 so as to selectively communicate with the cylinder bore 160. The discharge chamber 262 has a radius A suction chamber 264 is formed at a central portion of the rear housing 260. As shown in FIG.

A valve plate 280 is interposed between the cylinder block 120 and the rear housing 260. The discharge chamber 262 is connected to the cylinder bore 282 through a discharge port 282 formed in the valve plate 280, And the suction chamber 264 communicates with the cylinder bore 160 through an inlet port 284 of the valve plate 280. [

The swash plate 200 installed on the rotary shaft 140 is connected to the respective pistons 180 by a shoe 202 provided along the rim of the swash plate 200. The piston 180 is rotated by the rotation of the swash plate 200, And the cylinder bore 160 is reciprocated linearly. The angle of the swash plate 200 relative to the rotation axis 140 may be varied so that the amount of refrigerant discharged from the compressor 100 may be adjusted. For this purpose, the discharge chamber 262, The opening degree of the flow passage communicating with the pressure regulating valve 222 is adjusted by a pressure control valve (not shown).

FIG. 4 is an enlarged view of only the configuration of the refrigerant discharge flow rate measuring apparatus shown in FIG. 3, and shows the state of the compressor at the same time. 3 and 4, the rear housing 260 includes a main discharge passage 300 for discharging the refrigerant to the outside through an internal discharge chamber 262, and the main discharge passage 300, The bypass passage 310 is branched from the branch passage 310 to define a separate flow path and then joins with the main discharge passage 300 to form a bypass passage 310 for allowing refrigerant to flow out, A chamber 320 of a predetermined volume is formed in the flow path of the refrigerant.

The bypass passage 310 includes an inlet 312 for introducing the refrigerant into the chamber 320 and an outlet 312 for discharging the refrigerant from the chamber 320 to the main discharge passage 300. [ And the bypass passage 310 is formed through the inlet 312 of the bypass passage and the outlet 314 of the bypass passage, And is connected to the connection terminal 300 in a branched manner.

The chamber 320 is provided with a spool valve 330 that adjusts the displacement in accordance with the flow rate of the refrigerant flowing from the main discharge passage 300 through the bypass passage 310.

The spool valve 330 is a non-magnetic material and includes a first land 331 movably installed in the chamber 320 in a hermetic state so as to keep the inlet 312 of the bypass passage always open, The control unit controls the opening and closing of the bypass passage to the outlet 314 at a position spaced from the first land 331 in cooperation with the operation of the compressor 100, And a second land 332 that is set so as to have a smaller cross sectional area than the land portions 331 and 332 to allow the flow of the coolant between the first land 331 and the second land 332, (333).

In this case, the hydraulic pressure area of the first land 331 is set to be smaller than the hydraulic pressure area of the second land 332. Accordingly, when the compressor 100 is operated, if the refrigerant flows into the chamber 320 through the inlet 312 of the bypass passage, the spool valve 330 moves upward The bypass passage 310 is changed to a state as shown in FIG. 5, so that the bypass passage 310 is opened.

The spool valve 330 may further include a first return spring 334 that provides an elastic force to keep the outlet 314 of the bypass passage closed when the compressor 100 is in operation, The first return spring 334 is installed to urge the free end of the second land 332 in the chamber 320 toward the first land 331.

In this case, the spool valve 330 keeps the bottom surface of the first land 331 in contact with the chamber 320 while the compressor 100 is being driven. That is, the chamber 320 is formed so that the ratio of the compressor 100 can be in contact with the bottom surface of the first land 331 of the spool valve 330 at the same time.

The spool valve 330 includes a first land 331 and a second land 332 having different pressure receiving areas due to the pressure of the refrigerant introduced into the chamber 320 when the compressor 100 is operated, 5 by the force balance relationship between the bypass passage 310 and the bypass passage 310. As shown in FIG.

In addition, the chamber 320 may form a drain hole (not shown) communicable with the outside from at least one of the first land 331 and the second land 332 to discharge the refrigerant leaked The bar, in particular, the drain hole is set to communicate with the suction chamber of the compressor 100, and serves to re-supply the refrigerant leaked.

FIG. 6 and FIG. 7 are views showing a discharge flow rate measuring apparatus for a refrigerant according to another embodiment of the present invention, wherein FIG. 6 shows a non-moving state of the compressor and FIG. 7 shows a moving state of the compressor, respectively.

Referring to FIGS. 6 and 7, in another embodiment of the present invention, the spool valve 330 includes, in addition to the components shown in FIGS. 4 and 5, A first return spring 334 for providing an elastic force to keep the outlet 314 of the bypass passage 314 in a closed state and a second return spring 334 for providing an elastic force to switch the outlet 314 of the bypass passage to the open state when the compressor 100 is operated The first return spring 334 is arranged to move the free end of the second land 332 in the chamber 320 toward the first land 331 And the second return spring 335 is installed in the chamber 320 so as to press the free end of the first land 331 in the direction toward the second land 332.

At this time, the elastic force of the first return spring 334 and the second return spring 335 causes the inlet 312 of the bypass passage to be opened simultaneously with the ratio of the compressor 100, The spool valve 330 is set at a position where the spool valve 314 is closed so that when the compressor 100 is operated, the pressure of the refrigerant flowing into the chamber 320 is increased, 7, due to the force equilibrium relationship between the first land 331 and the second land 332 and the force balance relationship accompanied by the difference in elastic force between the first return spring 334 and the second return spring 335, And moves to the illustrated state to open the bypass passage 310.

In this case, the chamber 320 may form a drain hole (not shown) communicable with the outside from at least one of the first land 331 and the second land 332 to discharge the refrigerant leaked In particular, the drain hole is set to communicate with the suction chamber of the compressor 100, so that the refrigerant can be supplied again.

5 to 8, the spool valve 330 is provided with a magnetic body 340 therein, and the magnetic body 340 is displaced in accordance with the flow rate of the refrigerant flowing through the bypass passage 310 Moves with the spool valve 330 which is different.

The magnetic sensor 350 performs a function of detecting a change in the magnetic flux density which is accompanied by the displacement of the magnetic body 340. Particularly, the magnetic body 340 is installed in the groove 333 of the spool valve 330 and is connected to the spool valve 330 by the flow of the refrigerant through the bypass passage 310 when the compressor 100 is operated. Thereby allowing the magnetic sensor 350 to detect the magnetic flux density to be changed.

Alternatively, the magnetic body 340 may be installed on the first land 331 of the spool valve 330 shown in Figs. 4 and 5, or may be provided on the spool valve 330 shown in Figs. 6 and 7 The first land 331 and the second land 332 are provided in the first land 331 and the second land 332, respectively, so that a change in magnetic flux density that can be measured by the magnetic sensor 350 can be detected more precisely. In this case, it is needless to say that the magnetic sensor 350 is installed at a position covering the entire displacement section of the magnetic body 340 from the side of the chamber 320.

The refrigerant discharge flow rate measuring apparatus of the compressor according to the present invention includes a bypass passage 310 which is branched from the main discharge passage 300 in communication with the refrigerant discharge chamber 262 and is connected to the main discharge passage 300 again, And a spool valve 330 for generating a dependent displacement in response to the discharge flow rate of the refrigerant flowing in the bypass passage 310 during the operation of the compressor 100. The spool valve 330 moves together with the spool valve 330 The amount of the refrigerant discharged through the main discharge passage 300 can be reduced by providing a magnetic body 340 and a magnetic sensor 350 for detecting a change in magnetic flux density from the displacement of the magnetic body 340 on the outside, As shown in FIG.

In this case, the total amount of the refrigerant discharged through the main discharge passage 300 is different from the amount of the refrigerant flowing through the bypass passage 310, but the flow cross sectional area of the main discharge passage 300 and the bypass passage 310 The total flow amount of the refrigerant can be easily calculated from the flow amount of the refrigerant detected from the displacement of the spool valve 330 using the bypass passage 310. [

That is, the present invention measures the change of the magnetic flux density based on the displacement of the spool valve interlocked with the discharge flow rate of the refrigerant in the bypass path branching from the main discharge path, rather than measuring the discharge flow rate by the differential pressure as in the prior art, Since the discharge flow rate is calculated, more accurate measurement of the discharge flow rate is made possible.

As a result, the present invention can optimally control the torque required to operate the compressor 100 by accurately measuring the amount of refrigerant discharged during operation of the compressor 100, thereby reducing unnecessary loss of the engine driving force Can be minimized and energy efficiency can be improved.

Further, since the present invention does not require the formation of a throttling portion as compared with a refrigerant flow rate measuring apparatus of the conventional compressor, it is easy to manufacture equipment, and in particular, when the differential pressure between the high-pressure chamber and the low- The problem that the accurate measurement of the flow rate can not be performed can be solved.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limited to the particular details of the embodiments set forth herein. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.

100-compressor 120-cylinder block
122-center bore 140-rotation axis
160-cylinder bore 180-piston
200-swash plate
300-main discharge passage 310-bypass passage
320-chamber 330-spool valve
340-magnetic body 350-magnetic sensor

Claims (12)

A measuring device for detecting a flow rate of a refrigerant discharged to the outside through a discharge chamber (262) of a compressor (100)
A main discharge passage (300) in communication with the discharge chamber (262);
A bypass passage 310 branched from the main discharge passage 300 and merging with the main discharge passage 300;
A chamber 320 formed in the bypass passage 310;
A spool valve (330) for variably controlling displacement according to a flow rate of a refrigerant installed and bypassed in the chamber (320);
A magnetic body 340 installed on the spool valve 330; And
And a magnetic sensor (350) for detecting a change in magnetic flux density accompanied by a displacement of the magnetic body (340). The method according to claim 1,
The bypass passage 310 includes an inlet 312 for introducing a refrigerant into the chamber 320 and an inlet 312 for introducing refrigerant from the inside of the chamber 320 to the main discharge passage 300. [ And an outlet (314) of the bypass passage formed to discharge the refrigerant discharged from the compressor. The method of claim 2,
The spool valve 330 is a non-magnetic material, and includes a first land 331 for keeping the inlet 312 of the bypass passage in an open state;
A second land (332) for adjusting opening and closing of the bypass passage (314) at a position spaced apart from the first land (331) in conjunction with operation of the compressor (100); And
And a groove (333) for allowing the flow of the refrigerant between the first land (331) and the second land (332). The method of claim 3,
Wherein the pressure area of the first land (331) is set to be smaller than the pressure area of the second land (332). The method of claim 3,
Wherein the spool valve (330) further comprises a first return spring (334) for providing an elastic force so as to close the outlet (314) of the bypass passage at the expense of the compressor (100) Flow measurement device. The method of claim 5,
Wherein the first return spring (334) is installed to press the second land (332) in the chamber (320) in the direction toward the first land (331) . The method of claim 3,
The spool valve 330 includes a first return spring 334 that provides an elastic force to close the outlet 314 of the bypass passage when the compressor 100 is in operation, Further comprising a second return spring (335) for providing an elastic force to open the outlet (314) of the pass passage. The method of claim 7,
The first return spring 334 is installed to urge the second land 332 in the chamber 320 in the direction toward the first land 331 and the second return spring 335 is disposed in the chamber 320 The elastic force of the first return spring 334 and the second return spring 335 is set so as to press the first land 331 in the direction toward the second land 332 in the chamber 320, The spool valve 330 is set to be positioned at a position that opens the inlet 312 of the bypass passage and closes the outlet 314 of the bypass passage at the same time as the ratio of the compressor 100 is exceeded Wherein the refrigerant discharge flow rate measuring device of the compressor. The method of claim 3,
Wherein the chamber 320 forms a drain hole communicating with the suction chamber 264 of the compressor 100 on the back surface of at least one of the first land 331 and the second land 332 Refrigerant discharge flow rate measuring device for a compressor. The method of claim 3,
Wherein the magnetic body (340) is installed in a groove (333) of the spool valve (330). The method of claim 3,
Wherein the magnetic body (340) is installed in each of the first land (331) and the second land (332) of the spool valve (330). The method according to claim 1,
Wherein the magnetic sensor (350) is installed at a position covering the entire displacement section of the magnetic body (340) at the side of the chamber (320).

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