JPH08296930A - Detecting device of abnormality of refrigerant compressor - Google Patents

Abstract

PURPOSE: To lower a pressure loss of refrigerating equipment, to ensure high reliability and also to reduce the number of fitting processes and cost. CONSTITUTION: A detecting device of abnormality has a refrigerant flow detecting means 4 which is equipped with a reed switch 16, a slide valve 15 disposed displaceably inside a refrigerant passage 26, a first permanent magnet 19 shaped like a ring practically and retained in the slide valve 15 and a second permanent magnet 20 shaped like a ring practically and provided at a prescribed position of the refrigerant passage 26. The first and second permanent magnets 19 and 20 are disposed in the direction wherein they attract each other and the reed switch 16 is so disposed as to pierce a through part 28 of the slide valve 15 and the second permanent magnet 20. When a flow of refrigerant ceases, the first permanent magnet 19 is displaced by the attraction generated between the first and second permanent magnets 19 and 20, the reed switch 16 is made to operate and abnormality in a movable state of a refrigerant compressor is detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerant compressor abnormality detection device.

[0002]

2. Description of the Related Art Generally, in a vehicle air conditioner, a refrigerant compressor used in a refrigeration cycle is driven by a vehicle running engine via an electromagnetic clutch. The rotational output of the engine is transmitted to the electromagnetic clutch via a belt, but since many auxiliary machines other than the refrigerant compressor are mounted on the vehicle, the belt that is shared by the refrigerant compressor and a plurality of auxiliary machines is used. The engine is driven through. Therefore, when an abnormality occurs in each auxiliary machine including the refrigerant compressor, it is necessary to immediately detect the abnormality, protect the belt, and take measures to secure the driving force to the other auxiliary machines.

In view of this, Japanese Patent Laid-Open No. 58-141860 proposes a lock detecting device for determining an abnormal state (lock state) of the refrigerant compressor based on the presence or absence of the flow of the refrigerant. This lock detecting device is composed of a slide valve arranged in the refrigerant pipe, a position detecting means for detecting the position of the slide valve, a spring for urging the slide valve to an initial position, and the like. When the refrigerant flows, that is, when the refrigerant flows by the operation of the refrigerant compressor, the slide valve is displaced against the biasing force of the spring. Therefore, it is possible to determine that the refrigerant compressor is in the locked state when the position detecting means detects that the slide valve is in the initial position, despite the operation signal of the refrigerant compressor being output. .

[0004]

However, in the above lock detecting device, since the spring is used as a means for urging the slide valve to the initial position, the spring constant is set to reduce the low pressure loss of the refrigeration cycle. Need to lower. Further, in order to secure the reliability of the lock detecting device, it is necessary to enhance the durability of the spring. In this way, in order to reduce the pressure loss of the refrigeration cycle and enhance the durability of the lock detecting device, it is necessary to use a spring made of a special material, resulting in an extremely high cost.

Further, the conventional lock detecting device is constituted by a component separate from the refrigerating cycle and is connected to the refrigerant pipe by a pipe joint. Therefore, an increase in the number of joints for piping causes an increase in cost and a problem that the number of assembly steps of the refrigeration cycle increases. The present invention has been made to solve the above-mentioned problems, and the first
It is an object of the present invention to provide a refrigerant compressor abnormality detection device that can reduce the pressure loss of the refrigeration system and ensure high reliability at low cost. A second object is to provide an abnormality detecting device for a refrigerant compressor, which can be assembled in a refrigeration cycle without increasing the number of piping joints, thereby reducing the assembly man-hour and cost. Especially.

[0006]

In order to achieve the above object, in the invention described in claims 1 to 5, the refrigerant pipe (1
In 3), the displacing member (1) is displaceable between an initial position set in the passage direction and a displacement position downstream of the initial position.
5) is arranged, and the displacement member (15) is connected to the refrigerant pipe (1).
3) When the refrigerant flows in the inside, it receives the flow of the refrigerant, is displaced to the above-mentioned displacement position, and has a penetrating portion (28).

The penetrating portion (2) of the displacement member (15)
8) Integral with the displacement member (15) so as to enclose the first
A permanent magnet (19) is provided, and an attractive force or repulsive force is generated between the permanent magnet (19) and the first permanent magnet (19).
A substantially hollow polygonal or substantially annular second permanent magnet (2
0) is arranged at a predetermined position in the refrigerant pipe (13),
When there is no flow of the refrigerant in the refrigerant pipe (13), the displacing member (15) is urged to the initial position by the attractive force or the repulsive force.

The penetrating portion (2) of the displacement member (15)
8) and the magnetic detecting means (16) is arranged so as to penetrate through the central portion of the second permanent magnet (20). The change in magnetism due to the displacement of the permanent magnet (19) is detected. Therefore, when there is no refrigerant flow in the refrigerant pipe (13) due to the deactivation of the compressor (1), the repulsive force generated between the first permanent magnet (19) and the second permanent magnet (20). Alternatively, the displacing member (15) is biased to the initial position by the attractive force. On the other hand, when the refrigerant flows through the refrigerant pipe (13) by the operation of the compressor (1), the first permanent magnet (19)
The displacement member (15) is displaced to the displacement position against the repulsive force or attractive force generated between the second permanent magnet (20) and the second permanent magnet (20).
The first permanent magnet (19) is also displaced along with the displacement of the displacement member (15) due to the presence or absence of the flow of the refrigerant in the refrigerant pipe (13). The presence or absence of the flow of the refrigerant in the refrigerant pipe (13) can be detected by detecting the change in the magnetic field due to the displacement of the first permanent magnet (19) by the magnetic detection means (16).

Further, since the displacement member (15) is biased to the initial position by the repulsive force or attractive force generated between the first permanent magnet (19) and the second permanent magnet (20), it has been conventionally used. Since it is easier to obtain a small biasing force as compared with the case where the displacement member (15) is biased to the initial position by the spring, the low pressure loss of the refrigeration system can be achieved. In addition, high reliability can be obtained by using a permanent magnet having excellent durability. As a result, it is not necessary to use a spring made of a special material, and the cost can be reduced.

Further, the penetrating portion (2) of the displacement member (15)
8) The first permanent magnet (19) that surrounds the circumference of
By providing, the magnetic flux of the first permanent magnet (19) becomes the strongest at the penetrating portion (28). On the other hand, since the shape of the second permanent magnet (20) is a substantially hollow polygonal shape or a substantially annular shape, the magnetic flux of the second permanent magnet (20) is strongest in the central portion. And magnetic detection means (16)
By arranging the magnetic fluxes of the two permanent magnets at the strongest magnetic fluxes, such as the through portion (28) of the displacement member (15) and the central portion of the second permanent magnet (20). The change in magnetism due to the displacement of 19) can be detected more reliably and sensitively by the magnetism detecting means (16).

Further, in claim 2, when there is no flow of the refrigerant in the refrigerant pipe (13), the displacement member (1
Since 5) is biased to the initial position, the displacement member (15) is moved to the initial position by utilizing the attractive force generated between the first permanent magnet (19) and the second permanent magnet (20). By biasing the displacement member (15), the displacement member (15) can be stopped only at the initial position or the displacement position, and chattering of the magnetic detection means (16) due to fluctuations in the amount of refrigerant can be prevented. Therefore, it is possible to provide a more stable refrigerant compressor abnormality detection device.

Further, in claim 3, the magnetic detection means (1
6) is the first when the displacing member (15) is in the initial position based on the magnetic action of the first permanent magnet (19).
When the displacement member (15) is in the above-mentioned displacement position, the second operation state is established. And a compressor determination means (5) for determining whether the refrigerant compressor (1) is in an operating state or a stopped state,
Further, the compressor determination means (5) is used for the refrigerant compressor (1).
When it is determined that the magnetic field is operating, the magnetic detection means (1
When the state signal indicating the first operating state is input from 6) for a certain period of time, the compressor abnormal state determination means (5) for determining that the refrigerant compressor (1) is in an abnormal state is provided. It has a feature.

Therefore, it is determined that the refrigerant compressor (1) is in the locked state when the magnetism detecting means (16) is in the first operating state even when the refrigerant compressor (1) is in the operating state. can do. Therefore, when the compressor determination means (5) determines that the refrigerant compressor (1) is in the operating state,
When the state signal indicating the first operating state is input from the magnetic detection means (16) for a certain period of time, it can be determined that the refrigerant compressor (1) is in an abnormal state.

Further, in claim 4, the refrigerant flow detecting means (4) is a pipe joint (2) for connecting the refrigerant pipes (13) to each other.
4 and 25), it is possible to increase the number of pipe joints (24, 25) used in the refrigeration cycle without increasing
The refrigerant flow detection means (4) can be made compact. Further, this makes it possible to prevent an increase in cost associated with an increase in the number of pipe joints (24, 25) and prevent an increase in the number of assembly steps of the refrigeration cycle.

Further, in the invention according to claim 5, the attractive force is applied to the attractive surface (20a, 19a) of at least one of the first permanent magnet (19) and the second permanent magnet (20). Protrusions (20b, 20c,
19b) is partly provided and this protrusion (20
b, 20c, 19b) are provided so as not to interfere with the movement of the displacement member (15) between the initial position and the displacement position.

Here, in general, the magnetic force of the permanent magnet is lowered when the temperature is environmentally high, and when the compressor oil is present, the displacement of the displacement member (15) is hindered by the viscosity of this oil. , Especially the displacement member (1
When 5) moves from the displaced position to the initial position, the attractive force between the first and second permanent magnets (19, 20) tends to be insufficient.

On the other hand, according to the invention described in claim 5, when the displacement member (15) is at the displacement position, the first
The shortest distance between the permanent magnet (19) and the second permanent magnet (20) is shorter than that in the case where the protrusions (20b, 20c, 19b) are not provided. Therefore, the attractive force generated between the first permanent magnet (19) and the second permanent magnet (20) can be increased, and the valve return when moving the displacement member (15) from the transition position to the initial position. The power can be increased. Therefore, when the refrigerant stops flowing from the state where the refrigerant is flowing, the displacement member (15) can be more reliably
The displacement position can be moved to the initial position.

Also, the protrusions (20b, 20c, 19b)
Is provided so as not to hinder the movement of the displacement member (15), and does not shorten the moving distance of the displacement member (15). Therefore, the moving distance of the first permanent magnet (19) provided integrally with the displacement member (15) is not shortened, and the amount of change in magnetism due to the first permanent magnet (19) is also reduced. Absent. Therefore, the protrusions (20b, 20c,
By providing 19b), the detection of the change in magnetism by the magnetism detection means (16) is not hindered.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) The abnormality detection device 2 of the refrigerant compressor 1 is
A refrigerant flow detecting means 4 for detecting the locked state of the refrigerant compressor 1 used in the refrigeration cycle 3 of the vehicle air conditioner, and a refrigerant flow detecting means 4 for detecting the presence or absence of the flow of the refrigerant, and the refrigerant flow detecting means 4
The control means 5 is provided to control the operation of the refrigerant compressor 1 based on the detection signal.

As shown in FIG. 2, the refrigeration cycle 3 includes a refrigerant compressor 1 driven by a vehicle running engine (not shown) via an electromagnetic clutch 6, and a high temperature compressed by the refrigerant compressor 1. Cooling fan 7 for high pressure refrigerant
Refrigerant condenser 8 which condenses and liquefies by receiving the blown air, receiver 9 which temporarily stores the refrigerant guided by this refrigerant condenser 8 and flows only the liquid refrigerant, and an expansion valve which decompresses and expands the liquid refrigerant guided by this receiver 9. 10, a refrigerant evaporator 12 for evaporating the refrigerant whose pressure has been reduced by the expansion valve 10 by receiving air from a fan 11
And each of them is connected in an annular shape by a refrigerant pipe 13.

The electromagnetic clutch 6 is controlled based on a control signal output from the control means 5 via the clutch drive circuit 14, and is connected by energizing a built-in exciting coil (not shown). Then, the rotational output of the traveling engine transmitted via the belt is transmitted to the refrigerant compressor 1. When the energization of the exciting coil is cut off, the transmission of the rotation output to the refrigerant compressor 1 is cut off due to the open state.

The refrigerant pipe 13a on the refrigerant compressor 1 side and the refrigerant pipe 13b on the refrigerant condenser 8 side are connected to each other by connecting a pipe joint 24 and a pipe joint 25 which are pipe joints. In addition, these pipe joints 2
4, 25 and the refrigerant pipes 13a, 13b are made of a corrosion resistant metal material, for example, an aluminum alloy. In the abnormality detection device 2 of the refrigerant compressor 1 according to the present embodiment, the refrigerant flow detection means 4 (see FIG. 1) for detecting the presence or absence of the flow of the refrigerant is integrally formed with the pipe joint 24.

As shown in FIG. 1, the piping joint 24 has a coolant passage 26 formed therein, and the coolant passage 2
A pipe connection port 24a to which the refrigerant pipe 13a on the refrigerant compressor 1 side is connected by welding, brazing, or the like is provided on one end side (upstream side) of 6. On the other hand, the other end side (downstream side) of the refrigerant flow path 26 is provided with a joint connection port 24b into which a pipe joint 25 to which the refrigerant pipe 13b on the refrigerant condenser 8 side is connected is fitted. The refrigerant flow path 26 is formed by bending 90 degrees between the pipe connection port 24a and the joint connection port 24b.

The refrigerant flow detecting means 4 has a reed switch 16 which is a magnetic detecting means and the inside of the refrigerant flow path 26.
A slide valve (displacement member) 15 arranged to be displaceable between an initial position and a displacement position, and a slide valve 15 by applying an urging force to the slide valve 15 against the flow of the refrigerant.
Is provided with a first permanent magnet 19 and a second permanent magnet 20 (which will be described later) which are displacement member stopping means for stopping the initial position.

The reed switch 16 has a pair of magnetic tongues 16a whose tips are contacts, and both tongues 16a in a magnetic field.
When a is attracted to each other and the contacts come into contact with each other, a closed state (first operating state) is obtained. Outside the magnetic field, the contacts are separated due to the elasticity of the tongue pieces 16a to be in the open state (second operating state). This reed switch 16 is a slide valve 1
It is housed inside the cover 17 so that the contact point of the reed switch 16 is located on the radially inner circumference of the first permanent magnet 19 when 5 is in the displaced position. The lead wires 16a, 16a of the reed switch 16 are connected to the connector 1
It is resin-molded by 6b, and this connector 16b is integrally fixed to the cover 17.

The lead wires 16a, 16a are electrically connected to the control means 5, and the reed switch 16
When the contact is closed, an ON signal indicating the closed state is output to the control means 5 via the lead wires 16a and 16a, and when the contact is opened, an OFF signal indicating the open state is output to the control means 5. . The cover 17 has a cylindrical projecting portion 18 at the center of its axis, and the diameter of the projecting portion 18 is smaller than that of the refrigerant passage 26. The protruding end of the protruding portion 18 is closed, but the other end is open, and the reed switch 16 is housed inside the protruding portion 18. Further, the periphery of the protruding portion 18 is a groove-shaped portion 17a.

The cover 17 is fixed to the opposite side of the joint connection port 24b in such a direction that the projecting portion 18 thereof is on the inner side of the refrigerant flow path 26 and hermetically closes the refrigerant flow path 26. The second permanent magnet 20 has a substantially annular shape, and its size is such that it can be arranged in a groove-shaped portion 17 a formed around the protruding portion 18 of the cover 17. Further, the inner circumference thereof is substantially equal to the outer circumference of the protruding portion 18 of the cover 17.

The second permanent magnet 20 is held by the holding member 27 in such a direction that an attractive force acts between the second permanent magnet 20 and the first permanent magnet 19, which will be described later, when the second permanent magnet 20 is placed. As shown in FIG. 4, the holding member 27 is a substantially disc-shaped member having a crank-shaped cross section, and has a protruding annular portion at its axial center. This annular portion penetrates through, and its size is such that the protruding portion 18 of the cover 17 can slide. The second permanent magnet 20 is held on the disk surface of the holding member 27 on the side having the annular portion.

A holding member 2 holding the second permanent magnet 20.
7 is arranged so that the protruding portion 18 of the cover 17 penetrates the central portion of the substantially annular second permanent magnet 20.
It is fixed to the bottom surface of the groove-shaped portion 17a of No. 7 by a method such as adhesion or press fitting. The slide valve 15 has a substantially cylindrical shape as shown in FIG. 3, and flanges 15a and 15d are provided at both ends thereof (upper and lower ends in FIG. 3). The flanges 15a and 15d are provided at the center of the shaft with the protrusion 18 of the cover 17
Has a through hole for forming a through portion 28 for passing through. The diameter of the penetrating portion 28 is such that the protrusion 18 can slide on the penetrating portion 28.

The upper portion of the flange 15a has a substantially annular first portion.
Of the permanent magnet 19 of the flange 15 forming the penetration 28.
The through hole of a and the central portion of the first permanent magnet 19 are held so as to overlap with each other. By holding the first permanent magnet 19 in this manner, a through portion 28 is formed by the central portion of the first permanent magnet 19 and the through holes of the flanges 15a and 15d, and the first permanent magnet 19 has a through portion. It is provided so as to accommodate 28. The first permanent magnet 19 has a flange 15a.
Since it is held on the upper part of the slide valve, it is displaced integrally with the slide valve 15.

Between the flange 15a and the flange 15d, three plate-shaped members 15b are provided in a portion from the peripheral edge of the through portion 28 to the outer periphery of the flange 15a. A refrigerant passage 15c is formed between the plate-shaped members 15b so that the refrigerant can pass from the circumferential direction of the slide valve 15 to the penetrating portion 28. The slide valve 15 is arranged so that the flange 15a faces the groove-shaped portion 17a. Therefore, the flange 15a (upper end portion in FIG. 3) is attached to the groove-like portion 17a of the cover 17 by the flange 15a.
d is in sliding contact with the inner circumference of the refrigerant flow path 26. Further, the protruding portion 18 of the cover 17 penetrates the penetrating portion 28 and is arranged so as to be slidable. The slide valve 15 is
An initial position where the refrigerant passage 15c is located on the outer periphery of the protruding portion 18 of the cover 17 (a position where the slide valve 15 is in the closed state; the position shown in FIG. 1) and a flange 15d are provided on the inner periphery of the joint connection port 24b. Displacement position in contact with the stepped portion 24c (position where the slide valve 15 is in the open state;
(Position shown in FIG. 5).

Then, the first and second permanent magnets 19 and 20
Are arranged such that the magnetizing directions of the two permanent magnets 19 and 20 are parallel to the displacement direction of the slide valve 15, and the first permanent magnet 19 and the second permanent magnet 20 are The different magnetic poles are arranged so as to face each other. As a result, attractive force acts between the first permanent magnet 19 and the second permanent magnet 20 in a direction parallel to the displacement direction of the slide valve 15. Therefore, when the refrigerant compressor 1 is stopped and there is no refrigerant flow in the refrigerant pipe 13, the slide valve 15 is urged to the initial position by the attractive force generated between the first permanent magnet 19 and the second permanent magnet 20. Will be done.

However, when the discharge pressure of the refrigerant compressor 1 becomes larger than the attractive force generated between the first permanent magnet 19 and the second permanent magnet 20, the slide valve 15 is displaced by the discharge pressure of the refrigerant compressor 1. Is displaced to. That is, even when the slide valve 15 is biased to the initial position by the attractive force when the refrigerant compressor 1 is stopped, when the refrigerant compressor 1 is operated and the refrigerant is discharged, the refrigerant flow is received. The slide valve 15 is displaced to the displacement position.

The compressor control device 5 is, as shown in FIG.
Input / output interface 5a, ROM5b, RAM5
c, a microcomputer having a CPU 5d built therein. By turning on the air conditioner switch 22 while the ignition switch 21 of the running engine is on, the energization control of the electromagnetic clutch 6 via the clutch drive circuit 14 is performed. The refrigeration cycle 3 is started by performing.

The control means 5 has a compressor judging function for judging whether the refrigerant compressor 1 is in an operating state or a stopped state, and it is judged by this compressor judging function that the refrigerant compressor 1 is in an operating state. When the refrigerant compressor 1 is in the locked state, the compressor abnormal state determination function that determines whether the refrigerant compressor 1 is in the locked state, and when the refrigerant abnormality determination function determines that the refrigerant compressor 1 is in the locked state It has a control function in case of abnormality. The abnormal condition control is a lock warning device 23 for informing an occupant that the refrigerant compressor 1 is in a locked state.
(For example, a warning light, a warning buzzer, etc.) are operated, and the electromagnetic clutch 6 is turned off to stop the operation of the refrigerant compressor 1.

Next, the operation of this embodiment will be described. When the operation of the refrigerant compressor 1 is stopped and the refrigerant flow in the refrigerant pipe 13 disappears, as shown in FIG.
By the attractive force acting between the second permanent magnet 20 and
The slide valve 15 moves to the initial position. Slide valve 15
When is moved to the initial position, the refrigerant cannot pass through the refrigerant passage 15c, and the slide valve 15 is closed. At this time, the first permanent magnet 19 is displaced together with the slide valve 15 and is in a state of approaching the reed switch 16. Therefore, the reed switch 16 is in the closed state (first operating state), and the ON signal indicating the closed state is output to the control means 5.

On the other hand, when a refrigerant flow occurs in the refrigerant pipe 13 due to the operation of the refrigerant compressor 1, as shown in FIG.
The slide valve 15 is displaced in the refrigerant flow direction (downward in FIG. 8) by the differential pressure across the slide valve 15, and moves to the displacement position. When the slide valve 15 moves to the displaced position, the refrigerant can pass through the refrigerant passage 15c, and the slide valve 15 is in an open state. At this time, the first permanent magnet 19
Is displaced together with the slide valve 15, and the reed switch 16
It becomes a state away from. Therefore, the reed switch 1
6 is in an open state (second operating state), and an off signal indicating the open state is output to the control means 5.

FIG. 7 is a flow chart showing the operation of this embodiment. When the ignition switch 21 and the air conditioner switch 22 are turned on (when the determination results of step S1 and step S2 are both on), it is determined whether or not the electromagnetic clutch 6 is in the connected state (step S3, compressor). Judgment function). If the determination result of step S3 is YES (electromagnetic clutch 6: engaged state),
The open / closed state of the Lee 1 switch 16 is determined (step S4).

When the electromagnetic clutch 6 is in the engaged state in step S3, the rotational output of the engine is transmitted to the refrigerant compressor 1 and the refrigerant compressor 1 operates, so that the refrigerant flows in the refrigerant pipe 13. . As a result, the refrigerant pipe 13
The slide valve 15 disposed inside is displaced to the displacement position by receiving the flow of the refrigerant, and is displaced together with the slide valve 15.
The reed switch 16 is closed by receiving the magnetism of the permanent magnet 19 of FIG. Therefore, in step S4, the electromagnetic clutch 6
If the reed switch 16 is in the closed state despite the connection state, the refrigerant does not flow in the refrigerant pipe 13. That is, whether the refrigerant compressor 1 is in the locked state can be determined by the open / closed state of the reed switch 16.

Therefore, in step S4, the reed switch 1
When it is determined that 6 is in the open state, it is determined whether the duration t _{OFF of the} open state is a fixed time t _o (for example, 3 seconds) or more (step S5). This step S5
When the determination result of is YES (t _OFF ≧ t _O ), it is determined that the refrigerant compressor 1 is in the locked state (step S6 / compressor abnormal state determination function), the lock warning device 23 is activated, and The energization of the electromagnetic clutch 6 is stopped to protect the refrigerant compressor 1 (steps S7 and S8).
・ Abnormal control function).

As described above, in this embodiment, the presence or absence of the flow of the refrigerant can be judged by utilizing the attractive force generated between the first permanent magnet 19 and the second permanent magnet 20, and the refrigerant compression An abnormal operation of the machine 1 can be detected. Also,
The attractive force generated between the two permanent magnets 19 and 20 changes in a quadratic curve as shown in FIG. 8 according to the displacement amount of the slide valve 15 (distance between the two permanent magnets 19 and 20). (The reaction force characteristic of the spring is shown by the broken line graph). Therefore, a small reaction force is obtained as compared with the case where a conventional spring is used (that is, the urging force that urges the slide valve 15 when the slide valve 15 is in the initial position is small), so that the low pressure of the refrigeration cycle 3 is low. It is possible to make a loss. Further, since the use of the two permanent magnets 19 and 20 makes it difficult for the vibrations associated with the displacement of the slide valve 15 to occur and has excellent durability, the reliability upon repeated use becomes extremely high.

In the above embodiment, the first permanent magnet 19 and the second permanent magnet 2 which are the displacement member stopping means.
0 has a substantially annular shape, and the central portion thereof has a structure in which the reed switch 16 which is the magnetic detection means penetrates. In the case of a substantially annular permanent magnet, the magnetic flux at the center thereof is the strongest. Therefore, by arranging the reed switch 16 at the strongest magnetic flux portion as in the present embodiment, the slide valve can be more reliably and sensitively. A change in the magnetic field due to the displacement of 15 can be detected.

Further, in this embodiment, the refrigerant flow detecting means 4
Since it is configured integrally with the pipe joint 24,
The refrigerant flow detection means 4 can be assembled to the refrigeration cycle 3 without increasing the number of piping joints used in the refrigeration cycle 3. Further, the refrigerant flow detection means 4 can be configured more compactly than when it is configured as a separate component from the pipe joint 24. Further, since the outer circumferences of the first permanent magnet 19 and the second permanent magnet 20 are held by the slide valve 15 and the holding member 27, respectively, the entire magnets are not exposed to the flow of the refrigerant. . As a result, it is possible to protect from foreign matter contained in the refrigerant, so that it is possible to improve operation reliability.

(Second Embodiment) Next, an embodiment in which the slide valve 15 is stopped at the initial position by a repulsive force will be described. In the above embodiment, the slide valve 1 is utilized by using the attractive force generated between the first permanent magnet 19 and the second permanent magnet 20.
Although the example in which 5 is biased to the initial position side is shown, the first permanent magnet 19 and the second permanent magnet 20 are biased to the initial position side by utilizing the repulsive force generated between them. You may provide so that it may be energized.

FIG. 9 is a diagram showing the second embodiment.
The slide valve 15 has substantially the same shape as that of the first embodiment, but a plate-shaped member 15b provided between the flange 15a and the flange 15d is provided along the penetrating portion 28. However, a space is provided between the plate-shaped members 15b, and a refrigerant passage 15c is formed so that the refrigerant can pass from the circumferential direction of the slide valve 15 to the penetrating portion 28. Further, as in the first embodiment, the first permanent magnet 19 is provided on the upper portion of the flange 15a.
However, it is held so that a repulsive force is generated between the second permanent magnet 20 and the second permanent magnet 20 which will be described later.

On the other hand, the second permanent magnet 20 has a holding member 27.
It is fixed to the groove-shaped portion 17a of the cover 17, but is fixed to the downstream side of the refrigerant from the first permanent magnet 19, that is, the joint connection port 24b side. In addition, the second permanent magnet 20 is arranged so that a repulsive force is generated between the second permanent magnet 20 and the first permanent magnet 19. The slide valve 15 can be displaced between the initial position and the displacement position as in the first embodiment. The rest of the configuration is similar to that of the first embodiment described above, and the description thereof is omitted.

Next, the operation of this embodiment will be described.
When the operation of the refrigerant compressor 1 is stopped and there is no refrigerant flow in the refrigerant pipe 13, as shown in FIG. 9, a repulsive force acting between the first permanent magnet 19 and the second permanent magnet 20. The slide valve 15 returns to the initial position. At this time, the reed switch 16 is closed by the magnetic force of the first permanent magnet 19.

On the other hand, when a refrigerant flow occurs in the refrigerant pipe 13 due to the operation of the refrigerant compressor 1, the slide valve 15 causes the slide valve 15 to flow in the refrigerant flow direction (see the lower part of FIG. 9) due to the pressure difference before and after the slide valve 15. Direction) and move to the displacement position. At this time, the reed switch 16 is opened by the approach of the first permanent magnet 19. The other operations are the same as those in the first embodiment, and the description thereof will be omitted.

As an embodiment, the first permanent magnet 19
An example in which the slide valve 15 is biased toward the initial position side by using the attractive force and the repulsive force generated between the second permanent magnet 1 and the second permanent magnet 20 has been shown.
The arrangement method of 9 and 20 is preferably such that an attractive force is generated between them. Due to the force generated between the first permanent magnet 19 and the second permanent magnet 20, the slide valve 15 receives a force to displace it to the initial position (hereinafter referred to as a valve return force). The valve return force changes in a quadratic curve according to the opening area of the slide valve 15. FIG. 10 shows the opening area of the slide valve 15 when the attractive force and the repulsive force generated between the first permanent magnet 19 and the second permanent magnet 20 are used (first and second embodiments). Changes in the valve return force are shown (solid lines AB and DE in FIG. 10).

In the case of the abnormality detecting device utilizing the attractive force, when the slide valve 15 is closed, that is, when the opening area of the slide valve 15 is minimized, the two permanent magnets 19 and 20 are used.
Are in contact with each other and the force generated between the two permanent magnets 19 and 20 is large, so that the valve return force is large (state of point A). On the other hand, the slide valve 15 opens and the slide valve 15
When the opening area of the two becomes large, the two permanent magnets 19, 20
The distance between them increases and the valve return force decreases (point B state). That is, in the case of using the attractive force, the quadratic curve is rising upward (solid line AB).

On the other hand, in the case of the abnormality detecting device utilizing repulsive force, when the slide valve 15 is closed, that is, when the opening area of the slide valve 15 is minimized, the distance between the two permanent magnets becomes large, and Since the force generated between the two permanent magnets is small, the valve return force is small (state at point E). On the other hand, when the slide valve 15 opens and the opening area of the slide valve 15 increases, the distance between the two permanent magnets 19 and 20 decreases, and the valve return force increases (points C and D). In other words, in the case of using repulsive force,
It changes like a quadratic curve rising to the left (solid line DE).

By the way, the slide valve 15 receives a force from the refrigerant which is a fluid. This force (hereinafter, referred to as slide valve actuating force) becomes smaller as the refrigerant passes through the slide valve 15 as the opening area of the slide valve 15 becomes larger. Therefore, in FIG. 10, the slide valve actuating force shown by the broken line changes to the right upward as in the case of the abnormality detecting device utilizing the attractive force (the one-dot chain line in FIG. 10). When the flow rate of the refrigerant increases, this line shifts to the upper left (two-dot chain line in FIG. 10).

By the way, the force that the slide valve 15 receives from the refrigerant, that is, the slide valve operating force, and the two permanent magnets 19,
The position of the slide valve 15 is determined at a point where the force generated by 20 to displace the slide valve 15 to the initial position, that is, the valve return force is balanced. In FIG. 10, in the case of the abnormality detection device using the attractive force, the valve return force 15
10 does not intersect with the change curve (solid line AB in FIG. 10) and the change curve of the slide valve operating force (one-dot chain line and two-dot chain line in FIG. 10). Therefore, the slide valve 15 stands still at the point A or the point B depending on the presence or absence of the refrigerant flow rate regardless of the refrigerant flow rate. Therefore, unnecessary chattering of the reed switch 16 can be prevented, and a more stable abnormality detecting device can be provided. On the other hand, in the case of an abnormality detecting device utilizing repulsive force, a change curve of the valve return force (solid line in FIG. 10). DE) and the change curve of the slide valve actuation force (one-dot chain line and two-dot chain line in FIG. 10). That is, since the slide valve actuating force and the valve returning force are balanced with each other, the slide valve 15 becomes stationary between the points C and D depending on the amount of refrigerant. When vibration occurs due to the disturbance of the flow of the refrigerant, chattering of the reed switch 16, which is the magnetic detection means, may be caused when the slide valve 15 is stationary in this way. Moreover, chattering of the reed switch is likely to occur due to vibrations received from the outside, and malfunctions are likely to occur.

For the reasons described above, it can be said that the two permanent magnets are preferably arranged such that an attractive force is generated between them. (Third Embodiment) As shown in FIGS. 10 and 11,
In this embodiment, as in the first embodiment, the first and second permanent magnets 19 and 20 are arranged so that attractive force acts between the first permanent magnet 19 and the second permanent magnet 20. It is arranged. The second permanent magnet 20 in the first embodiment is characterized in that the annular protrusion 20b is integrally provided.

Specifically, the first permanent magnet 20 of the first permanent magnet 20
On the surface 20a of the permanent magnet 19 side, an annular protruding portion 20b that annularly protrudes toward the first permanent magnet 19 side is formed integrally with the second permanent magnet 20 at the outer peripheral edge portion of the surface 20a. The second permanent magnet 20 is fixed to the groove-shaped portion 17a of the cover 17 with an adhesive. Since the inner diameter of the annular protrusion 20b is slightly larger than the outer diameter of the second permanent magnet 20, the annular protrusion 20b is located between the initial position and the displacement position of the slide valve 15. Does not hinder the movement of.

As a result, while maintaining the moving distance of the slide valve 15 from the transition position to the initial position as in the first embodiment, when the slide valve 15 is in the transition position shown in FIG. Permanent magnet 19 and second permanent magnet 20
The shortest distance between and can be shortened as compared with the first embodiment. Therefore, when the slide valve 15 is in the transition position, the first permanent magnet 19 and the second permanent magnet 20 are
It is possible to increase the attractive force generated between the slide valve 1 and the initial position shown in FIG. 11 from the transition position shown in FIG.
The valve return force when moving 5 can be increased. Therefore, the slide valve 15 can be moved more reliably when the flow of the refrigerant stops flowing.

Further, since the moving distance of the slide valve 15 from the transition position to the initial position is maintained in the same manner as in the first embodiment, by providing the annular protrusion 20b, the magnetic change by the reed switch 16 can be prevented. It does not interfere with the detection. When the slide valve 15 is at the initial position shown in FIG. 11, the attractive force generated between the first permanent magnet 19 and the second permanent magnet 20 is mainly in the direction parallel to the displacement direction of the slide valve 15. The valve return force when moving the slide valve 15 from the state in the initial position shown in FIG. 11 to the transition position shown in FIG. 12 does not increase so much because it does not work much in the direction perpendicular to the displacement direction. That is, the provision of the annular protrusion 20b does not hinder the movement of the slide valve 15 when the refrigerant starts to flow.

In this embodiment, the reed switch 1
6 is arranged below the first embodiment in the figure. Therefore, when there is no refrigerant flow, the first permanent magnet 1
9 is separated from the reed switch 16, the reed switch 16 is in an open state (second operating state), and when there is a flow of the refrigerant, the first permanent magnet 19 is in a state of being close to the reed switch 16. Reed switch 16
Is in the closed state (first operating state).

(Fourth to Sixth Embodiments) In the third embodiment, the first permanent magnet 19 and the second permanent magnet 20 are used.
The shape may be a shape as shown in FIGS. Specifically, in the fourth embodiment shown in FIG. 13 (a), in the surface 19a of the first permanent magnet 19 on the second permanent magnet 20 side, the second permanent magnet 19 is formed on the inner peripheral edge of the surface 19a.
Of the second permanent magnet 20 is integrally formed, and an annular protrusion 20b protruding toward the first permanent magnet 19 is formed at the outer peripheral edge of the surface 20a of the second permanent magnet 20. Is formed. The outer diameter of the annular protrusion 19b of the first permanent magnet 19 is smaller than the inner diameter of the annular protrusion 20b of the second permanent magnet 20.

Further, in the fifth embodiment shown in FIG. 13B, the surface 19a of the first permanent magnet 19 has a tapered shape which rises from the outer peripheral side to the inner peripheral side,
The surface 20a of the second permanent magnet 20 is tapered so as to rise from the inner peripheral side to the outer peripheral side. The surface 19a of the first permanent magnet 19 has a shape corresponding to the surface 20a of the second permanent magnet 20.

In the sixth embodiment shown in FIG. 13C, the annular plate member 20c is fixed to the surface 20a of the second permanent magnet 20, and the outer peripheral edge portion of the annular plate member 20c is fixed. A protruding portion 20d corresponding to the annular protruding portion 20b of the third embodiment is integrally formed therewith. And
The outer diameter of the first permanent magnet 19 is smaller than the inner diameter of the protrusion 20d.

According to the fourth to sixth embodiments, the same effect as that of the third embodiment can be obtained. (Other Embodiments) In the above embodiment, the reed switch is used as the magnetic detection means, but other means such as a Hall element may be used.

Further, in the above embodiment, the refrigerant flow detecting means is formed integrally with the male piping joint, but it may be formed integrally with the female piping joint. Alternatively, the refrigerant flow detecting means may be provided in a state in which the male and female piping joints are connected. In the above embodiment, the outer peripheral surface of the slide valve 15 and the cover 1
The fitting gap with the inner peripheral surface of 7 may be made small, and the outer peripheral surface of the slide valve 15 or the inner peripheral surface of the cover 17 may be coated with a lubricating resin. As a result, the slide valve 15 can make smoother sliding contact with the groove-shaped portion 17a of the cover 17.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a refrigerant flow detection unit according to a first embodiment.

FIG. 2 is a diagram showing a refrigeration cycle according to the first embodiment.

FIG. 3 is a perspective view of a slide valve according to the first embodiment.

FIG. 4 is a perspective view of a holding member according to the first embodiment.

FIG. 5 is a block diagram relating to control of the first embodiment.

FIG. 6 is a diagram for explaining the operation of the refrigerant flow detection means in the first embodiment.

FIG. 7 is a flowchart showing the operation of the first embodiment.

FIG. 8 is a graph showing reaction force characteristics of a permanent magnet and a spring.

FIG. 9 is a cross-sectional view of a refrigerant flow detection unit according to the second embodiment.

FIG. 10 is a diagram showing a relationship between a valve return force and an opening area of a slide valve.

FIG. 11 is a cross-sectional view of a refrigerant flow detection unit in a state in which there is no refrigerant flow according to the third embodiment.

FIG. 12 is a cross-sectional view of a refrigerant flow detection unit in a state where there is a refrigerant flow in the third embodiment.

13A to 13C are partial cross-sectional views of the first and second permanent magnets showing the fourth to sixth embodiments.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Refrigerant compressor, 2 ... Abnormality detection device, 4 ... Refrigerant flow detection means, 13 ... Refrigerant piping, 15 ... Slide valve (displacement member),
16 ... Reed switch (magnetic detection means), 19 ... First permanent magnet, 20 ... Second permanent magnet, 28 ... Penetration part.

Claims (5)

[Claims] 1. Displaceable between an initial position set in the passage direction and a displacement position downstream of the initial position in a refrigerant pipe (13) in which the refrigerant discharged from the refrigerant compressor (1) flows. Displacement member having a penetrating portion (28), which is arranged and which, when the refrigerant flows through the refrigerant pipe (13) by the operation of the refrigerant compressor (1), receives the flow of the refrigerant and displaces to the displacement position. (15) and the penetrating part (2) of the displacement member (15) that is integrally displaced with the displacement member (15) in the refrigerant pipe (13).
8) The first permanent magnet (1
9) and a second substantially hollow polygonal shape or a substantially circular ring shape, which is arranged at a predetermined position in the refrigerant pipe (13) and generates an attractive force or a repulsive force with the first permanent magnet (19). The refrigerant pipe (13) is composed of a permanent magnet (20).
Displacement member stopping means for urging the displacement member (15) to the initial position by the attractive force or repulsive force when there is no refrigerant flow therein; the penetrating part (28) of the displacement member (15);
Of the first permanent magnet (1) which is disposed so as to penetrate through the central part of the permanent magnet (20) of the first permanent magnet (1).
An abnormality detecting device for a refrigerant compressor, comprising: a refrigerant flow detecting means (4) for detecting the presence / absence of a refrigerant flow, the magnetic detecting means (16) for detecting a change in magnetism due to the displacement of 9). 2. The displacement member stopping means comprises a first permanent magnet (19) and a second permanent magnet (20) for generating an attractive force between the first permanent magnet (19) and the first permanent magnet (19). The refrigerant compressor abnormality detection device according to claim 1, wherein the displacement member (15) is biased to the initial position by the attractive force when there is no refrigerant flow in the refrigerant pipe (13). . 3. The magnetic detection means (16) comprises:
On the basis of the magnetic action of the permanent magnet (19), when the displacement member (15) is in the initial position, it is in the first operation state, and when the displacement member (15) is in the displacement position, it is in the second operation state. A compression determination unit (5) that determines whether the refrigerant compressor (1) is in an operating state or a stopped state when the state is brought into a state, and the refrigerant compressor (1) by the compressor determination unit (5). When the state signal indicating the first operating state is input from the magnetic detection means (16) for a certain period of time when it is determined that the refrigerant compressor (1) is in an operating state, the refrigerant compressor (1) is in an abnormal state. An abnormality detection device for a refrigerant compressor according to claim 1 or 2, further comprising: compressor abnormal state determination means (5) for determining that there is. 4. The refrigerant flow detection means (4) is integrally formed with a pipe joint (24, 25) for connecting the refrigerant pipes (13) to each other. The refrigerant compressor abnormality detection device according to one. 5. The permanent magnet of at least one of the first permanent magnet (19) and the second permanent magnet (20), wherein the attractive surface (20a, 19a) projects in the attractive direction. Protrusions (20b, 20c,
19b) is partially provided, and the protrusions (20b, 20c, 19b) are provided so as not to interfere with the movement of the displacement member (15) between the initial position and the displacement position. The abnormality detecting device for a refrigerant compressor according to any one of claims 2 to 4, wherein: