JPH053864U - Refrigerant condition detector - Google Patents

Abstract

(57) [Abstract] [Purpose] Even when a refrigerant leak occurs, when the cooling efficiency does not decrease, it is prevented from being detected as a refrigerant shortage, and when the cooling efficiency decreases, it is possible to reliably detect the refrigerant shortage. To [Structure] The casing body 22 and the bottom plate 23 form a casing, and a bypass passage 25 including an inflow side bypass passage portion 25A, a bypass passage portion 25C, and an outflow side bypass passage portion 25B is formed in the casing. Then, the light emitting portion and the light receiving portion are arranged via the sight glass 26 so as to sandwich the bypass passage portion 25C. When the amount of refrigerant leakage increases, the refrigerant contained in the bubbles flows into the bypass passage 25, and the bubbles block the light from the light emitting unit.
The light receiving unit can detect the shortage of the refrigerant.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

  The present invention is provided, for example, in an air conditioner for automobiles, etc. The present invention relates to a refrigerant state detection device that is suitable for use in detecting whether or not a refrigerant is present.

[0002]

[Prior art]

  The present applicant previously mentioned in Japanese Patent Application No. 2-411494 (hereinafter referred to as prior art). And proposed an air conditioner equipped with an optical refrigerant state detection device.

[0003]   Therefore, FIGS. 9 to 11 show an optical refrigerant state detecting device according to the prior art of this type. 1 shows an air conditioner equipped with a unit.

[0004]   In the figure, 1 indicates a cooling cycle, and the cooling cycle 1 is ammonia, freon gas. A pipe 2 which forms a refrigerant flow path in which the refrigerant F such as a refrigerant circulates, and the refrigerant F in the middle of the pipe 2. 3, the compressor 3, which is installed in sequence along the circulation direction (direction A in the figure) The evaporator 5 includes an evaporator 4 and an evaporator 5. The evaporator 5 has an endothermic surface in an operator's cab (not shown). It is supposed to face inside. Then, the refrigerant F is compressed by the compressor 3. After being compressed, while passing through the condenser 4 and the evaporator 5, high pressure gas → high pressure liquid → low pressure A phase transition to gas and a phase transition from liquid to gas occur in the evaporator 5. First, heat is taken from the driver's cab to cool the driver's cab.

[0005]   6 is provided between the condenser 4 and the evaporator 5 and is provided in the middle of the pipe 2, and is in a liquid state. Is a receiver tank that temporarily stores the refrigerant F that has become A window 6A is provided so that the liquefaction status of the refrigerant F can be visually checked through the viewing window 6A. ing.

[0006]   7 is provided between the receiver tank 6 and the evaporator 5 and is provided in the middle of the pipe 2. An expansion valve is shown, and the expansion valve 7 is composed of a pressure reducing valve or the like, The refrigerant F, which is discharged in the liquid phase state, is decompressed to a predetermined pressure and flows in the direction of arrow A. Pass through. While the refrigerant F decompressed by the expansion valve 7 flows through the evaporator 5, It evaporates and becomes a gas phase state, and is compressed again by the compressor 3.

[0007]   8 is provided between the receiver tank 6 and the expansion valve 7 and provided in the middle of the pipe 2. A refrigerant sensor as an optical refrigerant state detecting device is shown, and the refrigerant sensor 8 is shown in FIG. As shown in FIG. 3, a cylindrical casing connected in the middle of the pipe 2 and forming a part of the refrigerant flow path. Casing 9 and a light emitting element 13 and a light receiving element 14 described later, and the like. A pair of cylindrical mounting portions 9A, 9A facing each other in the radial direction project outward in the radial direction. It is set up. Further, the casing 9 is located at the bottom of each mounting portion 9A, Diameter that is coaxial with the attachment portion 9A and smaller than the attachment portions 9A so as to communicate with the inside of the refrigerant passage. Through holes 9B, 9B in the direction and on the bottom side of each mounting portion 9A coaxially with each through hole 9B. The formed annular seal grooves 9C and 9C are provided.

[0008]   Reference numerals 10 and 10 denote O-rings 1 as seal members in the respective mounting portions 9A of the casing 9. 1 shows a sight glass arranged via 1, 11 and each sight glass 10 is transparent. Is formed into a thick disk shape with the glass material of FIG. It is sandwiched between the end surface on the end side and the casing 9 via each O-ring 11. That Then, each sight glass 10 closes one end side of each element holder 12, and the casing 9 The refrigerant F inside is prevented from entering the inside of each element holder 12 through each O-ring 11. It has become so.

[0009]   The O-rings 11 are installed in the seal grooves 9C of the casing 9, By sealing the space between the thing 9 and each sight glass 10, inside the casing 9 To prevent the refrigerant F flowing in the direction of arrow A from leaking from the through holes 9B to the outside. There is.

[0010]   12, 12, one end side is screwed to each mounting portion 9A of the casing 9, and the other end side is a case. The element holders that protrude radially from the single 9 are shown, and each element holder 12 is made of a metal material. A male screw part formed in a tubular shape by a material and screwed into the mounting part 9A on the outer circumference at one end side thereof. 12A is formed. The elements are provided on the inner circumference of the protruding end side of each element holder 12. An annular step 12C having a diameter larger than that of the insertion hole 12B is formed, and each step 12C is formed. Positions the light emitting element 13 and the light receiving element 14 in each element holder 12. ing.

[0011]   13 and 14 are inserted into the respective element holders 12, and the cylindrical holders are inserted into the respective element holders 12. The light emitting element and the light receiving element fixed via the mounting bolts 15 and 15 are shown. The optical element 13 and the light receiving element 14 are annular collar portions 13A and 14A and a pair of terminal pins 1. 3B and 14B, and the collar portions 13A and 14A are provided on the inner circumference of the protruding end side of each element holder 12. By screwing each mounting bolt 15, the tip surface of each mounting bolt 15 and each element It is sandwiched between the step portion 12C of the holder 12. Then, the light emitting element 13 and The light receiving element 14 is attached to each attachment portion 9A of the casing 9 via each element holder 12. Are arranged opposite to each other in the radial direction of the casing 9 with each sight glass 10 interposed therebetween. It

[0012]   Thus, the refrigerant sensor 8 allows the light receiving element 14 to receive the light from the light emitting element 13. As a result, the detection signal corresponding to the state of the refrigerant F flowing in the casing 9 in the direction of the arrow A is detected. The detection voltage V as a signal is output.

[0013]   In the prior art configured as described above, for example, a cooling cycle 1 is mounted on an automobile. At this stage, the refrigerant F such as Freon gas containing lubricating oil is filled in the pipe 2 to Turning on a switch (not shown) causes the compressor 3 to output rotational output from the engine. Driven by the compressor 3 and compressing the refrigerant F in the pipe 2 by the compressor 3, the arrow A direction Distribute it to others.

[0014]   Then, this refrigerant F is condensed while flowing through the condenser 4 and becomes a gas-liquid mixed state. After the gas and liquid are separated in the receiver tank 6, the refrigerant F in the liquid phase state moves the expansion valve 7 Through the inside of the evaporator 5, and while being evaporated (vaporized) in the evaporator 5, By taking heat away, the inside of the cab is cooled, and a vapor phase state is restored to the compressor 3 again. More compressed.

[0015]   Here, in the refrigerant sensor 8, the refrigerant F flowing in the direction of the arrow A in the pipe 2 is normally in a liquid phase. The light from the light emitting element 13 is disposed between the receiver tank 6 and the expansion valve 7, which are in the state of When the light receiving element 14 receives the light via the refrigerant F, the inside of the casing 9 is indicated by the arrow A. The detection signal corresponding to the state of the refrigerant F flowing in the direction is used as the detection voltage V in the control circuit (illustration Output).

[0016]   When the refrigerant F in the pipe 2 leaks to the outside and becomes insufficient, , The refrigerant F flowing through the casing 9 becomes a gas-liquid mixed state, and bubbles are generated to emit light. Is the light from the element 13 blocked by the air bubbles and the amount of light received by the light receiving element 14 decreases? As shown in FIG. 11, the detected voltage V from the refrigerant sensor 8 is lower than the predetermined voltage Vi. Down. As a result, the control circuit determines that the refrigerant F in the pipe 2 is insufficient, When an alarm device, such as an alarm lamp, is activated, a refrigerant shortage may occur due to refrigerant leakage. The driver etc. are informed of the presence.

[0017]

[Problems to be solved by the device]

  By the way, in the above-mentioned prior art, the refrigerant flow in the casing 9 formed in a substantially cylindrical shape. The light emitting element 13 and the light receiving element 14 are arranged so as to face the road in the radial direction. From the time when the refrigerant F in the refrigerant channel is properly filled, for example, about 7 to 13% to the outside. When leaking, this causes a relatively large amount of air bubbles to be generated in the refrigerant passage in the casing 9. When the light is emitted, the light from the light emitting element 13 is blocked by the bubbles and is received by the light receiving element 14. The amount of light is greatly reduced.

[0018]   Therefore, in the prior art, the amount of refrigerant leakage is about 7 to 13% compared to the time of proper filling. Then, the detected voltage V from the refrigerant sensor 8 becomes lower than the predetermined voltage Vi shown in FIG. Becomes low, and the control circuit determines that the refrigerant is insufficient at an early stage. However, the cooling cycle In Rule 1, if the refrigerant leakage rate is about 7% to 13%, the cooling efficiency will decrease. Is not always connected, and the refrigerant sensor 8 cannot detect the original lack of refrigerant. There's a problem.

[0019]   The present invention has been made in view of the above-mentioned problems of the prior art. Prevents early determination of refrigerant shortage when the ratio becomes 7 to 13% It is possible to detect the original lack of refrigerant when, for example, the refrigerant leakage rate becomes about 20%. It is an object of the present invention to provide a refrigerant state detection device capable of operating.

[0020]

[Means for Solving the Problems]

  In order to solve the above-mentioned problems, the configuration adopted by the first device is And a casing located below the refrigerant flow path of the casing. A bypass passage for bypassing the refrigerant passage of, and provided in the middle of the bypass passage, A refrigerant state detector for detecting the state of the refrigerant flowing in the bypass passage, The refrigerant state detector is composed of a light emitting unit and a light receiving unit which face each other across the bypass passage. I have configured it.

[0021]   Further, the configuration adopted by the second invention is such that the casing forming a part of the refrigerant flow path, It is located below the refrigerant flow path of the casing and forms a stagnation area in the refrigerant flow path of the casing. A stagnation part formed and a refrigerant provided in the stagnation part for detecting the state of the refrigerant in the stagnation part The refrigerant state detector includes a state detector, and the refrigerant state detector faces the light emitting portion with the stagnation portion interposed therebetween. And a light receiving section.

[0022]

[Action]

  Due to the above configuration, air generated in the initial state of refrigerant leakage (refrigerant leakage rate of around 10%) The refrigerant containing bubbles only flows in the refrigerant flow path, and does not flow into the lower bypass passage or stagnation. Not distributed to the department. Then, for example, the leakage of the refrigerant progresses to about 20%, and bubbles are generated. When the amount increases, the refrigerant containing bubbles flows into the bypass passage or the stagnation part, and the light emitting part The light from is blocked by the bubbles, and the amount of light received at the light receiving unit is reduced.

[0023]

【Example】

  An embodiment of the present invention will be described below with reference to FIGS. 1 and 8. In addition, in the example Are denoted by the same reference numerals as those of the above-mentioned prior art, and the description thereof will be omitted. I shall.

[0024]   First, FIGS. 1 to 4 show a first embodiment.

[0025]   In the figure, reference numeral 21 denotes a refrigerant sensor as a refrigerant state detecting device of the present embodiment. The sensor 21 is installed in a casing body 22 described below and below the casing body 22. The scraped bottom plate 23 and the bypass plate formed by the bottom plate 23 and the casing body 22. Provided so as to sandwich the bypass passage 25 and the bypass passage portion 25C of the bypass passage 25. The light emitting portion 27 and the light receiving portion 28 are generally configured.

[0026]   Reference numeral 22 denotes a casing body that constitutes a casing of the refrigerant sensor 21 together with the bottom plate 23. The outer shape of the casing body 22 is formed in a rectangular parallelepiped shape, and the upper side thereof has A refrigerant passage 22A forming a part of a refrigerant passage formed in the left-right direction in FIG. Provided with pipe mounting portions 22B, 22B formed at both end side openings of the refrigerant passage 22A. Has been. In addition, on the lower side of the casing main body 22, a lower surface is formed in the longitudinal middle portion. Is formed from the side to form a bypass passage portion 25C of the bypass passage 25. The concave portion 22C whose bottom side is closed by the bottom plate 23 and the concave portion 22C in the front-rear direction A penetrating hole that penetrates and forms an optical path between the light emitting unit 27 and the light receiving unit 28. The holes 22D, 22D and the through holes 22D on the outer side in the front-rear direction than the through holes 22D. The light emitting portion 27 and the light receiving portion 28 are formed through the large-diameter step portions 22E1 and 22E1. The mounting holes 22E and 22E are respectively configured to be mounted. That The pipes 2 and 2 are connected to the pipe mounting portions 22B by means such as welding. There is.

[0027]   Reference numeral 23 denotes a casing so that the recess 22C is closed below the casing body 22. A bottom plate liquid-tightly fixed to the lower surface of the main body 22 by screws 24, 24, 24, ... The bottom plate 23 is a thin plate-shaped mounting portion 23 fixed to the bottom of the casing body 22. A and a concave portion 22 of the casing body 22 which is provided so as to protrude from the central portion of the mounting portion 23A. It is composed of a fitting convex portion 23B inserted into C.

[0028]   25 is a casing book by attaching the bottom plate 23 to the casing body 22. 2 shows a bypass passage formed in the body 22, the bypass passage 25 being the case Formed on the main body 22, the lower end side communicates with both end sides of the recess 22C, and the upper end side Inflow side bypass passage section 25A communicating with the refrigerant passage 22A and outflow side bypass The passage portion 25B and the fitting convex portion 23B and the concave portion 22C. A bypass connecting the inlet side bypass passage portion 25A and the outlet side bypass passage 25B. It is composed of a passage portion 25C.

[0029]   Reference numerals 26 and 26 denote disc-shaped sight glasses, and each sight glass 26 is It is inserted into the step portion 22E1 of each mounting hole 22E of the single body 22.

[0030]   27 indicates a light emitting portion, and the light emitting portion 27 is one mounting hole of the casing body 22. A cylindrical element holder 27A screwed to 22E and having a step portion 27A1 on the inner peripheral side; The collar portion 27B1 is brought into contact with the step portion 27A1 of the element holder 27A, and the cylindrical mounting bolt And a light emitting element 27B mounted in the element holder 27A by means of Has been.

[0031]   Reference numeral 28 denotes a light receiving portion, which is the other mounting hole of the casing body 22. A tubular element holder 28A screwed to 22E and having a step portion 28A1 on the inner peripheral side; The collar portion 28B1 is brought into contact with the step portion 28A1 of the element holder 28A, and the cylindrical mounting bolt And a light receiving element 28B mounted in the element holder 28A by a switch 28C. Has been. The light receiving section 28 and the light emitting section 27 constitute a refrigerant state detector. The light emitting element 27B and the light receiving element 28B are controlled by a control circuit (not shown) as in the prior art. Connected to the road.

[0032]   Then, the light emitting unit 27 and the light receiving unit 28 are bypassed via each sight glass 26. The light emitting element 2 is arranged so as to face each other with the bypass passage portion 25C of the passage 25 interposed therebetween. The light from 7B is bypassed through one sight glass 26 and the through hole 22D. The refrigerant F in the passage portion 25C is transmitted therethrough, and the other through hole 22D and the sight glass 26 are provided. The light is received by the light receiving element 28B via the The detection voltage V is output.

[0033]   The refrigerant sensor 21 according to the present embodiment has the above-described configuration, and its basic There is no particular difference in operation from the prior art. Therefore, according to this embodiment The action of the bypass passage 25, which is a feature of the refrigerant sensor 21, will be described.

[0034]   That is, when the refrigerant F in the pipe 2 runs short due to refrigerant leakage or the like, the refrigerant F in the pipe 2 becomes A gas-liquid mixture occurs and bubbles are generated. Then, these bubbles are in the liquid state refrigerant F. As it floats upward, the initial state of refrigerant shortage (for example, refrigerant leakage rate 10 %)), Simply circulating in the refrigerant passage 22A of the casing body 22 As for the refrigerant F flowing into the bypass passage 25, the refrigerant F in a substantially liquid phase state flows in. this Therefore, the light from the light emitting element 27B of the light emitting section 27 is in the liquid phase state in the bypass passage section 25C. The light-receiving element 28B of the light-receiving portion 28 receives the light from the light-receiving element 28B. The detection voltage V output from the child 28B is a predetermined value as indicated by a characteristic line 29 shown by a solid line in FIG. The control circuit confirms that the voltage value is higher than the voltage Vi and is within the proper filling amount range. To inform you.

[0035]   On the other hand, when the amount of refrigerant leakage increases (for example, the refrigerant leakage rate is around 20%), the generated gas The number of bubbles increases, and the refrigerant F including bubbles not only flows in the refrigerant passage 22A, but also It also flows into the bypass passage 25. And bubbles from the refrigerant passage 22A Inside the bypass passage portion 25C through the inflow side bypass passage portion 25A Flow into the bypass passage portion 25C, the light from the light emitting element 27B of the light emitting portion 27 flows into the bypass passage portion 25C. Is blocked by the bubbles in the refrigerant F, and is received by the light receiving element 28B of the light receiving unit 28. The amount of light decreases. As a result, the detected voltage V output from the light receiving element 28B is As indicated by the characteristic line 29 in No. 4, the voltage becomes lower than the predetermined voltage Vi, and the refrigerant is insufficient. Notification from the control circuit.

[0036]   Thus, in the refrigerant sensor 21 of this embodiment, the casing is composed of the casing body 2 2 and a bottom plate 23, the refrigerant passage 22A is bypassed downward in the casing. A bypass passage 25 is formed, and the bypass passage of the bypass passage 25 is further formed. A light emitting portion 27 and a light receiving portion 28 which form a refrigerant state detector are provided so as to sandwich the portion 25C. Therefore, the light from the light emitting element 27B is not allowed to pass through the bypass passage 25. Amount of light received by the light receiving element 28B depending on the state of the refrigerant F flowing in the passage portion 25C Is changed to determine the refrigerant state.

[0037]   That is, the detection voltage V of the refrigerant sensor 21 is as shown by the characteristic line 29 shown by the solid line in FIG. Compared with the detection voltage V of the prior art shown by the dotted line, it becomes gentler, and there is less refrigerant leakage. At this time (refrigerant leakage rate is around 10%), the bubbles generated in the refrigerant F are not absorbed by the refrigerant passage 22. The light-emitting element 2 does not flow in the bypass passage 25 but only in the light-emitting element 2. The light from 7B is not blocked by the refrigerant F in the bypass passage 25 and the light receiving element 28B, the detection voltage V generates a voltage value higher than the predetermined voltage Vi, In technology, it is important not to notify that the refrigerant shortage has already been notified. it can. On the other hand, if the refrigerant leakage increases (the refrigerant leakage rate is around 20%), the refrigerant F The amount of bubbles generated in the refrigerant increases, and the refrigerant F containing bubbles flows in the refrigerant passage 22A. In addition to passing through, it also flows into the bypass passage 25. And the light emitting element 27B The light from is blocked by this bubble, the amount of light received by the light receiving element 28B is reduced, and The detection voltage V output from the light receiving element 28B has a voltage value lower than the predetermined voltage Vi. Therefore, it can be notified that the refrigerant is insufficient. In this way, the refrigerant sensor 21 With this configuration, it is possible to prevent the lack of refrigerant from being detected early as in the prior art. You can

[0038]   Therefore, in the refrigerant sensor 21 of the present embodiment, the initial state in which the refrigerant leak occurs (Refrigerant leakage rate is around 10%) It is possible to prevent notification of lack of refrigerant, and when refrigerant leakage increases (refrigerant leakage rate is 2 0%), that is, when the cooling efficiency deteriorates, this is reliably detected as a refrigerant shortage. It is possible to accurately notify when the refrigerant is insufficient.

[0039]   In the first embodiment, the light emitting element 27 is provided via the pair of sight glasses 26. Although the light from B is received by the light receiving element 28B, the present invention is not limited to this. The bypass passage portion 25C of the bypass passage 25 is formed of a glass tube. Formed so that the light emitting portion 27 and the light receiving portion 28 are arranged in the radial direction of the glass tube. You may. The bypass passage 25 is not only formed in the casing, but also Bypass passage located below the refrigerant passage 22A. The light emitting portion 27 and the light receiving portion 28 may be arranged so as to be sandwiched at the position.

[0040]   Next, a second embodiment of the present invention will be described with reference to FIG. 5 and FIG. The characteristic of the example is that a stagnation part is formed below the refrigerant passage in the casing and the stagnation part is sandwiched. The light emitting portion and the light receiving portion are provided. In the present embodiment, the above-mentioned first The same components as those of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. It

[0041]   In the figure, 31 denotes a refrigerant sensor as a refrigerant state detecting device of the present embodiment, The sensor 31 has substantially the same structure as the refrigerant sensor 21 of the first embodiment. The refrigerant sensor 31 includes a casing body 32, which will be described later, and the casing body 3 The bottom plate 33 provided on the lower side of 2, and the bottom plate 33 and the casing body 32 The formed stagnation portion 34, and the light emitting portion 27 provided so as to sandwich the stagnation portion 34, The light receiving section 28 is generally configured.

[0042]   Reference numeral 32 denotes a casing body that constitutes a casing of the refrigerant sensor 31 together with the bottom plate 33. And the casing body 32 is similar to the casing body 22 of the first embodiment. In addition, the refrigerant passage 32A forming a part of the refrigerant passage and the both end sides of the refrigerant passage 32A are opened. Pipe mounting portions 32B, 32B formed at the mouth are formed. Also, the case The single body 32 extends downward from the refrigerant passage 32A, and the left and right ends are A communication hole 32C formed in a semicircular shape with a roundness is provided. And the Through holes 32D, 32D are formed in the housing main body 32 in the front-back direction of the communication hole 32C. The stepped portions 32E1 and 32E1 are provided outside the through holes 32D in the front-rear direction, Mounting holes 32E, 32E for mounting the light emitting portion 27 and the light receiving portion 28 are formed. ing.

[0043]   33 is located on the lower side of the casing main body 32 and is provided with screws 24, 24, 24, ... A bottom plate fixed in a liquid-tight manner is shown, and the bottom plate 33 is fixed to the bottom of the casing body 32. A thin plate-shaped mounting portion 33A to be fixed, and a protrusion provided at the center of the mounting portion 33A. And a fitting convex portion 33B inserted into the communication hole 32C of the housing main body 32. ing.

[0044]   34 is a casing main body by fixing the bottom plate 33 to the casing main body 32. The stagnation part formed in the body 32 is shown, and the stagnation part 34 of the casing main body 32 is shown. It is formed between the communication hole 32C and the fitting convex portion 33B of the bottom plate 33.

[0045]   Further, the light emitting portion 27 and the light receiving portion 28 are provided in the respective mounting holes 32E of the casing body 32. The sight glasses 26, 26 are attached to each step 32E1. So Then, the light emitting portion 27 and the light emitting portion 27 are sandwiched so as to sandwich the stagnation portion 34 formed below the refrigerant passage 32A. And a light receiving portion 28 are provided.

[0046]   Thus, also in the refrigerant sensor 31 according to this embodiment, the first embodiment described above is used. Similarly, the bubbles in the refrigerant F generated when the refrigerant leakage rate is about 10% are When flowing through the refrigerant passage 32A of the main body 32 and the refrigerant leakage rate becomes about 20%, , The bubbles in the refrigerant F fall to the stagnation part 34 on the lower side, and the light from the light emitting part 27 is transferred to the bubbles. By shutting off the light by means of, the amount of light received by the light receiving portion 28 is reduced, and the leakage of the refrigerant is ensured. Can be detected.

[0047]   Furthermore, the third embodiment of the present invention will be described with reference to FIGS. 7 and 8. The feature of the embodiment is that an annular stagnation portion is formed in the refrigerant passage in the casing, and the lower side of the stagnation portion is formed. The light emitting portion and the light receiving portion are provided so as to sandwich the stagnation portion. Na In this embodiment, the same components as those in the first embodiment described above are designated by the same reference numerals. , The description is omitted.

[0048]   In the figure, reference numeral 41 denotes a refrigerant sensor as a refrigerant state detecting device of the present embodiment. The sensor 41 includes a casing body 42 having a bottomed cylindrical shape, which will be described later, and the casing body 42. And a cooling body formed in the casing body 42 by the lid body 43. The medium passage 44 and the stagnation portion 45 located below the refrigerant passage 44 are sandwiched between the casings. The light emitting portion 27 and the light receiving portion 28 provided on the casing main body 42. It

[0049]   Reference numeral 42 denotes a bottomed cylindrical shape that constitutes the casing of the refrigerant sensor 41 together with the lid 43. The casing main body 42 includes a cylindrical portion 42A and a bottom center. Formed on the outer side of the refrigerant inlet 42B and the refrigerant inlet 42B. The pipe mounting portion 42C and the tubular portion 42A, which are located below the tubular portion 42A, Through holes 42D, 42D that are pierced in the tangential direction, and the outside of each through hole 42D And the light emitting portion 27 and the light receiving portion 28 are connected via the step portions 42E1 and 42E1. The mounting holes 42E, 42E to be attached are generally configured.

[0050]   Reference numeral 43 denotes a lid that covers the opening of the casing body 42, and the lid 43 is a case. An annular mounting portion 43A fixed to the opening of the single body 42 and the casing main body A cylindrical fitting protrusion 43B inserted into the tubular portion 42A of the body 42, and the fitting protrusion 43 Refrigerant outlet 43C axially bored in the center of B, and refrigerant outlet 43C bored It is configured with a pipe mounting hole 43E formed outside in the installation direction. And the lid The body 43 is liquid-tightly fixed to the casing body 42 by screws 24, 24, 24, .... It

[0051]   Reference numeral 44 denotes a refrigerant passage which constitutes a refrigerant passage together with the pipe 2 and the like, and the refrigerant passage 44 is A casing formed by fixing a lid body 43 to the casing body 42. The refrigerant F formed in the main body 42 is supplied from the refrigerant inlet 42B to the refrigerant outlet 43C. Distribute. Further, in the refrigerant passage 44, the refrigerant inlet 42B and the refrigerant outlet 43 A portion below C becomes a stagnation portion 45, and a part of the refrigerant F flowing in the stagnation portion 45 is It will be temporarily housed.

[0052]   Further, the light emitting portion 27 and the light receiving portion 28 are provided in the respective mounting holes 42E of the casing body 42. The sight glasses 26, 26 are attached to each step 42E1. So The light emitting portion 27 and the stagnation portion 45 located below the refrigerant passage 44 are sandwiched between the light emitting portion 27 and A light receiving section 28 is provided.

[0053]   However, in this embodiment, bubbles generated when the refrigerant leakage rate is around 10% Flows into the refrigerant passage 44 together with the refrigerant F from the refrigerant inlet 42B, and the refrigerant passage 4 Collect on the upper side of 4. Then, when the refrigerant leakage rate becomes around 20%, the lower side of the refrigerant passage 44 That is, the bubbles also drop to the position between the light emitting portion 27 and the light receiving portion 28 within the stagnation portion 45. As a result of this bubble blocking the light from the light emitting unit 27, the light receiving unit 28 It is possible to detect the shortage of the refrigerant by reducing the amount of light received at.

[0054]   Thus, also in the refrigerant sensor 41 according to the present embodiment, the above-described first embodiment Although the same effect as the above can be obtained, particularly in the present embodiment, the casing structure is The manufacturing process can be simplified and the manufacturing process can be simplified to reduce the manufacturing cost. You can

[0055]   In each of the above-described embodiments, the element holders 27A, 2A of the light emitting portion 27 and the light receiving portion 28 are provided. The light emitting element 27B and the light receiving element 28B are mounted in the 8A by using respective mounting bolts 27C and 28C. However, the present invention is not limited to this, and each element holder 27A, From the protruding end side of 28A, the collar portions 27B1 and 28B1 of the elements 27B and 28B are connected to the step portion 2 A cylindrical set with a C-shaped cross section for fixing between 7A1 and 28A1. May be used.

[0056]

[Effect of device]

  As described above in detail, in the refrigerant state detecting device according to the present invention, the casing A bypass passage is provided below the refrigerant flow passage, and the light emitting unit and the bypass passage are sandwiched therebetween. Since the refrigerant state detector consisting of the light receiving part and the light receiving part is arranged, there is little refrigerant leakage. Occasionally, most of the bubbles generated in the refrigerant flow in the refrigerant flow path and the bypass passage on the lower side. It does not flow through the road and prevents the refrigerant condition detector from detecting this condition as insufficient refrigerant it can. When the amount of refrigerant leakage is large, the amount of bubbles generated in the refrigerant is As the refrigerant containing air bubbles increases and flows into the lower bypass passage, the refrigerant state is detected. This state can be detected as a refrigerant shortage by the container, and the refrigerant shortage can be notified. Therefore, at the time of the initial leak, despite the cooling efficiency not decreasing, the lack of refrigerant Is notified, and when the cooling efficiency drops, this is regarded as a refrigerant shortage. It can be surely notified.

[0057]   Furthermore, instead of the bypass passage, a stagnation is provided on the lower side of the refrigerant flow passage, and the stagnation part is cooled. Even if the medium state detector is installed, the refrigerant shortage in the initial state of refrigerant leakage Notification can be prevented, and when the cooling efficiency drops, it can be sure to notify the lack of refrigerant. Wear.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a refrigerant sensor according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a sectional view taken along the line III-III in FIG.

FIG. 4 is a characteristic diagram showing a detected voltage with respect to a refrigerant leakage rate by the refrigerant sensor of the present embodiment.

FIG. 5 is a vertical sectional view showing a refrigerant sensor according to a second embodiment of the present invention.

6 is a sectional view taken along the line VI-VI in FIG.

FIG. 7 is a vertical sectional view showing a refrigerant sensor according to a third embodiment of the present invention.

8 is a sectional view taken along the line VIII-VIII in FIG.

FIG. 9 is a circuit diagram showing an air conditioner according to the prior art.

FIG. 10 is a longitudinal sectional view of a refrigerant sensor according to the prior art.

FIG. 11 is a characteristic diagram showing the detected voltage with respect to the refrigerant leakage rate by the refrigerant sensor of the prior art.

[Explanation of symbols]

1 cooling cycle 2 piping 21, 31, 41 Refrigerant sensor (refrigerant state detection device) 22, 32, 42 Casing body 22A, 32A, 44 Refrigerant passage (refrigerant passage) 23, 33 bottom plate 25 bypass passage 27 Light emitting part 27B light emitting device 28 Light receiving part 28B light receiving element 34, 45 stagnation part 43 Lid F refrigerant

Claims (2)

[Scope of utility model registration request] 1. A casing forming a part of a refrigerant passage, a bypass passage located below the refrigerant passage of the casing and bypassing the refrigerant passage of the casing, and a bypass passage provided in the middle of the bypass passage. A refrigerant state detector for detecting the state of the refrigerant flowing in the bypass passage, the refrigerant state detector comprising a light emitting portion and a light receiving portion facing each other across the bypass passage. . 2. A casing forming a part of a refrigerant flow passage, a stagnation portion located below the refrigerant flow passage of the casing and forming a stagnation region in the refrigerant flow passage of the casing, and provided in the stagnation portion. And a refrigerant state detector for detecting the state of the refrigerant in the stagnation part, the refrigerant state detector comprising a light emitting part and a light receiving part which face each other with the stagnation part in between.