JP6106078B2 - Heater and heat pump system - Google Patents

Description

  The present invention relates to a heater and a heat pump system using a PTC (Positive Temperature Coefficient) element as a heat source.

  As a conventional main heat source for heating the interior of an automobile, a hot water heater that heats air using exhaust heat of engine cooling water is used, but the temperature of engine cooling water is low when the engine is started. Therefore, an electric heater is also used as an auxiliary heat source. In addition, it seems that the installation of electric heaters will be promoted with the spread of electric vehicles in the future.

  A device using a PTC element as a heating element in an electric heater is disclosed in Patent Document 1, for example. In Patent Document 1, a fluid heating device using a PTC element is disposed at an inlet of a heater core, the PTC element faces a flow path of engine cooling water through a partition wall, and fluid passing through the flow path is transferred to the PTC. A structure for heating with an element is disclosed.

JP 2008-7106 A

  In the case of the structure in which the liquid passing through the flow path is heated by the PTC element disclosed in Patent Document 1, the thermal efficiency is poor, the number of parts constituting the tank through which the liquid flows increases, and as a result, it becomes heavier, saving space, Cost reduction becomes difficult. In addition, since the electrically conducting portion is immersed in the liquid, there is a concern about the possibility of electric leakage.

  Therefore, a heating device in which the pipe portion through which the liquid flows and the electrically conductive PTC heat generating unit are completely separated is desirable. However, simply attaching a PTC heating element to the side surface of a pipe as conventionally known does not provide efficient heat conduction.

  The present invention has been made in view of the above-described problems. A heater and a heat pump system that can heat a fluid more efficiently, have excellent reliability and safety in actual use, and can be reduced in weight, space, and cost. provide.

According to an aspect of the present invention, there is provided a metal main body having a flow path through which a fluid flows and a plurality of cylindrical portions that are provided outside the flow path and each store a heat generating unit. A portion between the path and the cylindrical portion, and a main body in which the cylindrical portion is integrally continuous with the same metal material, and a sealing body that closes an end of the cylindrical portion, and the heating unit includes A PTC (Positive Temperature Coefficient) element having an electrode surface; an electrode plate bonded to the electrode surface; the electrode plate; A plurality of the heat generation units, each of the plurality of tube portions having at least a pair of tube portions provided at positions facing each other across the flow path. Units are provided at positions facing each other across the flow path. Also has a pair of heating units, the heating unit, the tube portion is pressed narrow between the inner wall of the direction connecting the pair of cylindrical portions facing each other across said flow path, said flow path and the heating unit There is no gap, and there is provided a heater characterized in that a continuous heat conduction path consisting only of the metal main body having an integral structure is provided.

  According to the present invention, the fluid can be heated more efficiently, and it is excellent in reliability and safety in actual use, and can be reduced in weight, space-saving, and cost reduction.

(A) And (b) is an external view of the heater of embodiment. The AA expanded sectional view in FIG. The enlarged view of the principal part in FIG. The schematic plan view of the heat generating unit in a cylinder part. The schematic diagram of the vehicle-mounted warm water heater system using the heater of embodiment. (A)-(c) is a schematic cross section showing the other specific example of a flow path. Sectional drawing which shows the other specific example of the part shown in FIG. The schematic cross section of the modification of the heater of embodiment. (A) And (b) is a schematic diagram which shows the electrode extraction part of the heater of embodiment. The schematic side view of the heater of embodiment. The schematic diagram of the heat pump system using the heater of embodiment. The schematic diagram of the heat pump system using the heater of embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same element in each drawing.

FIG. 1A is an external perspective view of the heater 1 according to the embodiment, and FIG. 1B is a side view of the heater 1.
FIG. 2 is an AA enlarged cross-sectional view in FIG.

  The heater 1 has a main body 11 and sealing bodies 23 provided at both ends in the longitudinal direction in which the main body 11 extends. The main body 11 is made of metal such as aluminum. The sealing body 23 is a cap such as a resin, for example.

  A flow path 50 is formed near the central axis of the main body 11 as shown in FIG. The channel 50 is formed along the longitudinal direction of the main body 11 so as to penetrate the longitudinal direction.

  An inlet portion 21 and an outlet portion 22 are integrally provided in the main body 11 at both ends in the longitudinal direction of the main body 11. The inlet portion 21 and the outlet portion 22 protrude from the sealing body 23, respectively.

  The inlet portion 21 is formed in a cylindrical shape, and the inside thereof communicates with the flow path 50. The outlet portion 22 is also formed in a cylindrical shape, and the inside thereof communicates with the flow path 50.

  A cylindrical portion 12 is provided on the side surface side of the main body 11. As shown in FIG. 2, the cylindrical portion 12 is integrally provided outside the flow path 50. Around the flow path 50, for example, four cylindrical portions 12 are provided every 90 °.

  The main body 11 including the inlet portion 21 and the outlet portion 22 is integrally formed by, for example, extrusion molding.

  A hollow portion 35 having a rectangular cross section is formed inside the cylindrical portion 12. The hollow portion 35 extends in the longitudinal direction of the main body 11 similarly to the flow path 50. The heating unit 10 is accommodated in the hollow portion 35.

  FIG. 3 shows a cross-sectional view of the heat generating unit 10 accommodated in a certain cylinder 12. FIG. 4 corresponds to a plan view of the cylindrical portion 12 viewed from below in FIG.

  The heat generating unit 10 includes a PTC (Positive Temperature Coefficient) element 16 as a heat generating element. The PTC element 16 is a ceramic element having a positive temperature characteristic, and when the temperature becomes equal to or higher than the Curie point, the resistance rapidly increases and further temperature rise is limited.

  The PTC element 16 is formed, for example, in the shape of a rectangular thin plate, and electrode surfaces 16a made of a metal such as silver or aluminum are formed on both front and back surfaces. A plurality of PTC elements 16 are arranged along the longitudinal direction of the cylindrical portion 12 inside the cylindrical portion 12.

  Electrode plates 41 and 42 are bonded to the pair of electrode surfaces 16a of the PTC element 16, respectively. The PTC element 16 is sandwiched between a pair of electrode plates 41 and 42. A voltage of opposite polarity is applied to the pair of electrode plates 41 and 42, respectively.

  The electrode plates 41 and 42 are superimposed on the electrode surface 16 a of the PTC element 16 inside the cylindrical portion 12. The electrode plates 41 and 42 and the electrode surface 16a are bonded with, for example, a silicone-based adhesive having excellent thermal conductivity.

  The electrode surface 16a is formed on the front and back surfaces of the PTC element 16 by spraying aluminum, for example. Alternatively, the electrode surface 16 a is formed by applying, for example, silver paste on the front and back surfaces of the PTC element 16. Or after apply | coating a silver paste to the front and back of the PTC element 16, the electrode surface 16a is formed by spraying aluminum. For this reason, fine irregularities are formed on the electrode surface 16a.

  Therefore, even if the adhesive for adhering the electrode surface 16a and the electrode plates 41 and 42 is insulative, the projections on the irregularities of the electrode surface 16a penetrate the adhesive and contact the electrode plates 41 and 42, so that the PTC The conduction between the element 16 and the electrode plates 41 and 42 can be ensured. Note that aluminum spraying is more desirable for reducing contact resistance.

  The electrode plates 41 and 42 and the PTC element 16 sandwiched between them are wrapped in an insulating sheet 21. The insulating sheet 21 has flexibility, thermal conductivity, and electrical insulation, and is, for example, a polyimide film. Both edge portions 21 a and 21 b of the insulating sheet 21 are overlapped with each other, and the insulating sheet 21 covers the electrode plates 41 and 42 bonded to the PTC element 16.

  The cylinder part 12 has the inner inner wall 31 provided in the flow path 50 side, and the outer inner wall 32 provided in the other side. The PTC element 16 has one electrode surface 16a facing the inner inner wall 31 side, that is, the flow path 50 side, and the other electrode surface 16a facing the outer inner wall 32 side.

  One electrode plate 41 is interposed between the inner inner wall 31 and one electrode surface 16a, and the other electrode 42 is interposed between the other electrode surface 16a and the outer inner wall 32.

  Both edge portions 21 a and 21 b of the insulating sheet 21 are overlapped not on the electrode surface 16 a of the PTC element 16 and the inner inner wall 31 but on the back side of the side surface 12 b of the cylindrical portion 12. Thereby, the fall of the heat transfer efficiency from the PTC element 16 to the flow path 50 can be suppressed.

  The cylindrical portion 12 is formed in a flat shape having an inner inner wall 31 and an outer inner wall 32 that face each other, and a pair of side surfaces 12b that are formed substantially at right angles to them and face each other. The inner inner wall 31 and the outer inner wall 32 are wider and larger in area than the side surface 12b.

  The PTC element 16 and the electrode plates 41 and 42 are accommodated inside the cylindrical portion 12 in a state where the periphery is covered with the insulating sheet 21. Between one electrode surface 16a and the inner inner wall 31, the electrode plate 41 and the insulating sheet 21 are narrowly pressed. Between the other electrode surface 16a and the outer inner wall 32, the electrode plate 42 and the insulating sheet 21 are narrowly pressed.

  After inserting the PTC element 16 and the electrode plates 41 and 42 wrapped with the insulating sheet 21 into the cylindrical portion 12, the cylindrical portion 12 is crushed by applying mechanical pressure in a direction connecting the inner inner wall 31 and the outer inner wall 32. As a result, the PTC element 16, the electrode plates 41 and 42, and the insulating sheet 21 are in a state of being compressed between the inner inner wall 31 and the outer inner wall 32, and are fixed in the cylindrical portion 12.

  Therefore, no gap is formed between the electrode surface 16a of the PTC element 16 and the flow path 50, and a part 33 of the metal main body 11 is integrally interposed. For this reason, a heat transfer path in which no air layer is interposed between the PTC element 16 and the liquid flowing in the flow path 50 can be secured over a wide area, and heat transfer efficiency can be improved.

  Since a groove or a depression is formed in the side surface 12b of the cylindrical portion 12 along the longitudinal direction, it is possible to prevent the side surface 12b from bulging outward when the cylindrical portion 12 is crushed.

  As shown in FIGS. 1A and 1B, sealing bodies 23 having electrical insulation, waterproofness, and heat resistance are provided at the openings at both ends of the cylindrical portion 12. In addition, a gap between the cylindrical portion 12 and the sealing body 23 is filled with, for example, a silicone-based sealing material having electrical insulation, waterproofness, and heat resistance. Thereby, the penetration | invasion of the liquid to the inside of the cylinder part 12 is prevented.

  An electric cable described later is connected to one end of each of the electrode plates 41 and 42, and the electric cable penetrates the sealing body 23 and is led out to the outside. The electric cable led out to the outside is connected to a power source. A portion where the electric cable penetrates the sealing body 23 is filled with, for example, a silicone-based sealing material having electric insulation, waterproofness, and heat resistance.

  The sealing body that closes the end of the cylindrical portion 12 in the embodiment includes a sealing body 23, for example, a silicone-based sealing material that fills a gap between the cylindrical portion 12 and the sealing body 23, For example, a silicone-based sealing material that fills a portion of the cable penetrating the sealing body 23.

  The heater 1 of the present embodiment can be mounted on, for example, an automobile and used as a heater for heating a vehicle. And the electric power from the battery mounted in the motor vehicle is supplied to the PTC element 16 via the electric cable and the electrode plates 41 and 42, and the PTC element 16 generates heat.

  This heat is transmitted to the metal main body 11 through the electrode plates 41 and 42 and the insulating sheet 21 and further to the liquid flowing through the flow path 50. For example, liquid such as water or antifreeze is introduced into the flow path 50. The liquid flows into the flow channel 50 from the inlet 21 and flows through the flow channel 50.

  The liquid flowing in the flow path 50 is heated by heat exchange with the portion 33 between the flow path 50 and the cylindrical portion 12 in the main body 11 heated by the heat generating unit 10, and flows out from the outlet portion 22 as hot water.

  The main body 11 having the flow channel 50 and the cylindrical portion 12 is an integral body formed by extrusion molding, for example, and the portion 33 between the flow channel 50 and the cylindrical portion 12 and the cylindrical portion 12 are integrally made of the same metal material. It is continuous. Further, the pipe 50 is not provided with a pipe separate from the main body 11. Therefore, an integral metal of the same material is continuously interposed between the inner inner wall 31 and the flow path 50. Further, the heat generating unit 10 is narrowed in the cylindrical portion 12, and the heat generating unit 10 is in close contact with the inner inner wall 31 without interposing an air layer. Therefore, the heat of the heat generating unit 10 can be efficiently transmitted to the liquid flowing through the flow path 50.

  The PTC element 16 has a characteristic of releasing energy as it cools. Therefore, the heat of the heat generating unit 10 is efficiently removed from the flow path 50 side where the liquid having a lower temperature flows, and as a result, the amount of heat escaping from the outer inner wall 32 side of the cylindrical portion 12 to the opposite side of the flow path 50 is suppressed. .

  Further, in the main body 11, the volume of the portion 33 between the flow path 50 and the inner inner wall 31 is larger than the volume of the outer portion 34 than the outer inner wall 32. Therefore, as represented by an arrow A in FIG. 2, the heat transferred to the portion 34 on the opposite side of the flow channel 50 in the main body 11 passes through the portion 33 in which the cross-sectional area of the path toward the flow channel 50 is increased. It can be efficiently transmitted to the flow path 50.

  Due to the characteristics of the PTC element 16 described above and the structure of the main body 11, even if the heat generating unit 10 is located outside the flow path 50, most of the energy of the heat generating unit 10 is transferred to the inner flow path 50 side. Communicate towards. That is, the liquid can be efficiently heated while suppressing the heat escaping to the opposite side of the flow path 50.

  The present inventors performed the following experiment using the heater 1 of the embodiment.

  In an initial state before supplying power to the heat generating unit 10, the inlet water temperature of running water was 9.0 ° C., the environmental temperature was 18 ° C., and the running water amount was 10 liters / minute.

  The outlet water temperature of the running water was 13.6 ° C. in a state where the applied voltage was 350 V DC, the current value was 9.2 A, the amount of power was 3220 W, and power was supplied to the heating unit 10.

Since calorie (J) = 4.2 × mass of water (g) × rising temperature of water (° C.), calorie (J) is 4.2 × 10000 (g) × 4.6 (° C.) = 193200 (J).
Further, since electric energy (J) = power (W) × time (seconds), 193200 (J) / 60 seconds (minutes) = 3220 (W).

  That is, 3220 W of electrical energy can be converted into 3220 W of heat, and the efficiency is 100%.

  Conventionally, in order to transfer heat from a metal containing a heating element to a medium such as a liquid, a heat sink is attached to increase the contact area. On the other hand, in the present embodiment, the heat generated from the heat generating unit 10 is not secured by securing the volume of the portion 33 while utilizing the characteristics of the PTC element 16 instead of securing a large contact area. Realized efficient transmission to liquid.

  Since the liquid efficiently removes heat, the output of one PTC element 16 can be taken out to the limit. Therefore, the number of PTC elements 16 to be used can be reduced. As a result, the entire heater can be reduced in weight, space saving, and cost reduction, which can greatly contribute to society.

  As shown in FIG. 2, the heater 1 is accommodated in, for example, a metal case 60. Alternatively, the case 60 may be made of resin.

  In the heater 1, the sealing body 23 or the inlet portion 21 and the outlet portion 22 at both ends thereof are both supported by the wall portion of the case 60. That is, both ends of the heater 1 are supported by the case 60, and the main body 11 is floating in the internal space of the case 60. Therefore, the outer surface of the main body 11 does not contact the inner wall of the case 60, and a gap exists between the main body 11 and the inner wall of the case 60.

  For this reason, it is difficult for the heat of the main body 11 to escape to the case 60 and the outside thereof. Moreover, since the main body 11 is covered with the case 60, it can prevent that a person and an object touch the surface of the heated main body 11, and can improve safety | security.

  Between the main body 11 and the case 60, air may be interposed as a heat insulating layer, or a gas having higher heat insulating properties such as CFC gas may be interposed.

  Alternatively, as shown in FIG. 7, the outer surface of the main body 11 may be covered with, for example, a silicone-based sponge-like heat insulating material 70. In this case, the case 60 may not be provided.

  In the present embodiment, the PTC element 16 and the electrode plates 41 and 42 that are in contact with the PTC element 16 are accommodated inside the cylindrical portion 12 sealed by the sealing body 23 and are not exposed to the outside. Moreover, since the insulating sheet 21 is interposed between the electrode plates 41 and 42 and the inner wall of the cylindrical portion 12, the cylindrical portion 12 is not energized. High safety and reliability can be obtained while obtaining high heat exchange efficiency.

  Next, FIG. 5 is a schematic diagram illustrating the in-vehicle hot water heater system of the embodiment.

  FIG. 5 shows a specific example in which the heater 1 described above is attached to a vehicle such as an automobile. The inlet portion 21 and the outlet portion 22 are connected to the circulation path 6.

  The circulation path 6 has pipe lines 6a to 6d. The pipe line 6 a connects the outlet portion 22 and the heater core 2. The pipe line 6 b connects the heater core 2 and the hydraulic pump 3. The pipe line 6c connects the hydraulic pump 3 and the three-way valve 4. The pipeline 6d connects the three-way valve 4 and the inlet 21.

  The circulation path 6 and the heater 1 are also connected to the engine 5 via pipe lines 7a and 7b. When the three-way valve 4 shuts off the conduit 6c and the conduit 7a and communicates between the conduit 6c and the conduit 6d, when the hydraulic pump 3 is driven, the heater 1 and The liquid circulates in the circulation path 6 in the direction indicated by the white arrow in FIG.

  At this time, by supplying electric power from the battery mounted on the vehicle to the heat generating unit 10 of the heater 1, the heat generating unit 10 generates heat, and the liquid in the flow path 50 is heated. The warm water generated by this heating is supplied to the heater core 2 through the outlet portion 22 and the pipe line 6a.

  Hot water supplied to the heater core 2 flows through a pipe provided in the heater core 2. Gas (air) is blown from the blower 8 to the heater core 2. Heat of the hot water flowing through the pipe of the heater core 2 is transmitted to the gas blown from the blower 8 through a heat transfer surface such as a fin provided in the heater core 2. As a result, warm air is blown into the vehicle. This mode is selected when the exhaust heat of the engine 5 cannot be used, for example, when the engine 5 is started.

  After the engine 5 is started, the three-way valve 4 is switched so that the pipe line 6c and the pipe line 7a communicate with each other, and the pipe line 6c and the pipe line 6d are shut off. Function as. The flow of the liquid at this time is represented by a black arrow in FIG. Hot water that has passed through the engine 5 and has been heated by heat exchange with the engine 5 is supplied to the heater core 2 via the pipe lines 7b and 6d, the inflow part 51, the flow path 50, the outlet part 22 and the pipe line 6a. Therefore, in this mode, hot water can be supplied to the heater core 2 without energizing (generating heat) the heat generating unit 10, and by driving the blower 8, hot air can be sent into the vehicle.

  By forming irregularities on the inner wall of the channel 50, the contact area between the inner wall and the liquid can be increased, and the heat exchange efficiency can be further increased.

  For example, FIG. 6A shows a flow channel 51 in which star-shaped irregularities are formed on the inner wall. FIG. 6B shows a flow path 52 in which corrugated irregularities are formed on the inner wall.

  Alternatively, as shown in FIG. 6 (c), the cross-sectional flow path 53 may be used to increase the contact area with the liquid.

  Further, the cylindrical portion 12 is not limited to a rectangular cylindrical flat shape, and may be an ellipse or a circle. As the distance between the PTC element 16 and the inner inner wall 31 is shorter, the efficiency of heat transfer to the portion 33 of the main body 11 can be increased.

  The number of each of the cylindrical portion 12 and the heat generating unit 10 is not limited to four, and is arbitrary according to the required size and output of the heater 1. For example, as shown in FIG. 8, the number of combinations of the cylinder part 12 and the heat generating unit 10 may be two. In the example shown in FIG. 8, the cylindrical portion 12 and the heat generating unit 10 are provided at positions facing each other across the flow path 50 in the main body 71.

  The heater 1 of the embodiment can be widely applied to uses other than the vehicle, and in any application, the liquid can be efficiently heated to generate hot water with a small, simple and low-cost configuration.

  Next, the extraction structure of the electrode plates 41 and 42 will be described.

  FIG. 9A is an end view of the outer side of one of the pair of sealing bodies 23 shown in FIGS. 1A and 1B (represented by reference numeral 23a in FIG. 9A).

  For example, the above-described outlet portion 22 in the main body 11 penetrates the center of the sealing body (first sealing body) 23a and protrudes to the outside. For example, a silicone-based sealing material 91 having electrical insulation, waterproofness, and heat resistance is provided in a portion where the outlet portion 22 penetrates the sealing body 23a.

  A continuous electrode connection plate 72 is provided on the outer peripheral side of the end face of the sealing body 23a. On the end face of the sealing body 23a, four slits 74 are formed on the inner side (center side) of the electrode connection plate 72. The four slits 74 are respectively formed at positions corresponding to the positions of the four cylindrical portions 12.

  The electrode terminal 43 protrudes from each slit 74. The electrode terminal 43 is integrally provided at the end of one of the pair of electrode plates 41 and 42 of the heat generating unit 10 (for example, the negative electrode plate).

  Each electrode terminal 43 is bent toward the electrode connection plate 72 and overlapped under the electrode connection plate 72. The electrode terminal 43 and the electrode connection plate 72 are fastened and fixed to the sealing body 23a with screws 81.

  Therefore, the negative electrode plates of the four heat generating units 10 are electrically connected to the common electrode connection plate 72. Furthermore, one end 85a of the electric cable 85 is also screwed to one of the four screwing portions. Accordingly, the negative electrode plates of the four heat generating units 10 are electrically connected to the common electric cable 85.

  FIG. 9B is an end view of the outer side of the sealing body (second sealing body) 23b provided at the end opposite to the sealing body 23a (the opposite side in the longitudinal direction of the flow path 50). It is.

  For example, the inlet portion 21 described above in the main body 11 passes through the center of the sealing body 23b and protrudes to the outside. For example, a silicone-based sealing material 92 having electrical insulation, waterproofness, and heat resistance is provided at a portion where the inlet portion 21 penetrates the sealing body 23b.

  Two electrode connection plates 77 and 78 are provided on the outer peripheral side of the end face of the sealing body 23b. The two electrode connection plates 77 and 78 are not connected spatially or electrically.

  On the end face of the sealing body 23b, four slits 75 are formed on the inner side (center side) of the electrode connecting plates 77 and 78. The four slits 75 are respectively formed at positions corresponding to the positions of the four cylindrical portions 12.

  The electrode terminal 44 protrudes from each slit 75. The electrode terminal 44 is integrally provided at the end of the other electrode plate (for example, the positive electrode plate) of the pair of electrode plates 41 and 42 of the heat generating unit 10.

  Two of the four electrode terminals 44 are bent toward the electrode connection plate 77 and overlapped under the electrode connection plate 77. The electrode terminal 44 and the electrode connection plate 77 are fastened and fixed to the sealing body 23a by screws 82.

  The other two of the four electrode terminals 44 are bent toward the electrode connection plate 78 and overlapped under the electrode connection plate 78. The electrode terminal 44 and the electrode connection plate 78 are fastened and fixed to the sealing body 23 a by screws 82.

  That is, two of the positive electrode plates of each of the four heat generating units 10 are electrically connected to the electrode connection plate 77. The other two positive electrode plates are electrically connected to the electrode connecting plate 78.

  One end 86a of the electric cable 86 is also screwed to one of the two screwing portions of the electrode connecting plate 77. Accordingly, two of the positive electrode plates of each of the four heat generating units 10 are electrically connected to the electric cable 86.

  One end portion 87a of the electric cable 87 is also screwed to one of the two screwing portions in the electrode connecting plate 78. Therefore, the other two positive electrode plates are electrically connected to the electric cable 87.

Note that the four positive electrode plates may be combined into one, similarly to the negative electrode side.
When the positive electrode plate is divided into a plurality of systems, the power applied between the plurality of heat generating units 10 can be varied. That is, it is possible to control only a part of the heat generation units 10 according to the situation, or to increase or decrease the heat generation amount of some of the heat generation units 10 than others.

  The electric cable 85 on the negative electrode side shown in FIG. 9A is led out to the side surface side of the main body 11 through the through hole 73 formed in the end surface of the sealing body 23a.

  As shown in FIG. 10, a cylindrical cable guide 100 is provided on the side surface of the main body 11. The cable guide 100 has electrical insulation and heat resistance, and is a quartz tube, for example.

  The electric cable 85 passes through the inside of the cable guide 100 and is guided to the end face side of the sealing body 23b through the through hole 76 formed in the end face of the other sealing body 23b shown in FIG. 9B. .

  Therefore, all the electric cables 85, 86, 87 can be led out of the main body 11 from the same end face side. In addition, by using the electrode connection plates 72, 77, 78 described above, the number of electrical cables drawn out can be reduced. Therefore, according to the embodiment, the connection work between the electric cables 85, 86, 87 and the external power supply becomes easy.

  The positive electrode connection plates 77 and 78 are provided at one end of the main body 11 in the longitudinal direction, and the negative electrode connection plate 72 is provided at the other end of the main body 11 in the longitudinal direction. This electrode lead-out structure can increase the creeping distance between the positive and negative electrodes and ensure high safety as compared with a structure in which positive and negative electrode connecting plates are provided at the same end of the main body 11. In addition, the electrode extraction structure of the embodiment can reduce the area of the electrode extraction portion at the end of the main body 11 as compared with the structure in which the positive and negative electrode connecting plates are provided at the same end of the main body 11, and the heater 1 as a whole. Can be miniaturized.

  Next, a specific example in which the heater 1 of the embodiment is applied to a heat pump system will be described.

  FIG. 11 is a schematic diagram of the heat pump system. This heat pump system includes two heat exchangers 101 and 105, an expansion valve 103, a compressor 107, and the heater 1 of the above-described embodiment.

  A refrigerant circulates in the system. The refrigerant is compressed by the compressor 107 and sent to the heat exchanger 101 through the pipe 108 in the state of high-temperature and high-pressure gas. The refrigerant is condensed by heat exchange with the fluid to be heated (air or liquid) in the heat exchanger 101 and sent to the expansion valve 103 through the pipe 102 in a high-temperature and high-pressure liquid state.

  The refrigerant expanded by the expansion valve is sent to the heat exchanger 105 through the pipe 104 in a low-temperature and low-pressure liquid state. By the heat exchange with the atmosphere or the like in the heat exchanger 105, the refrigerant is evaporated and sent to the compressor 107 through the pipe 106 in the state of a low-temperature and low-pressure gas, and the above-described cycle is repeated.

  The heater 1 is connected to a pipe 108 between the compressor 107 and the heat exchanger 101 and heats the compressed gas sent from the compressor 107 to the heat exchanger 101. That is, the heater 1 assists the refrigerant heating in the path between the compressor 107 and the heat exchanger 101.

  The compressed gas flows in the aforementioned flow path 50 of the heater 1, and the gas is heated by the heat generating unit 10. That is, the heater 1 is effective not only for liquid but also for heating gas.

  In addition, as shown in FIG. 12, the heater 1 may be connected to a pipe 102 between the heat exchanger 101 and the expansion valve 103 to heat the liquid flowing through the pipe 102.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 1 ... Heater, 10 ... Heat generating unit, 11 ... Main body, 12 ... Tube part, 16 ... PTC element, 16a ... Electrode surface, 21 ... Insulating sheet, 31 ... Inner inner wall, 32 ... Outer inner wall, 41 ... Electrode plate, 50- 53 ... Flow path

Claims (7)

A metal main body having a flow path through which a fluid flows and a plurality of cylindrical portions provided outside the flow path and each containing a heat generating unit, between the flow path and the cylindrical portion And a main body in which the portion and the cylindrical portion are integrally continuous with the same metal material;
A sealing body for closing the end of the cylindrical portion;
With
The heating unit is
A PTC (Positive Temperature Coefficient) element having an electrode surface;
An electrode plate bonded to the electrode surface;
An insulator provided between the electrode plate and the inner wall of the cylindrical portion and overlaid on the electrode plate;
Have
The plurality of cylindrical portions have at least a pair of cylindrical portions provided at positions facing each other with the flow channel interposed therebetween, and the plurality of heat generating units respectively accommodated in the plurality of cylindrical portions include the flow channel. Having at least a pair of heat generating units provided at positions facing each other,
The heat generating unit is confined between the inner walls of the cylindrical portion in a direction connecting the pair of cylindrical portions facing each other with the flow channel interposed therebetween, and there is no gap between the flow channel and the heat generating unit. A heater having a continuous heat conduction path formed only of the metal main body having an integral structure.   The heater according to claim 1, wherein the PTC element has the electrode surface directed toward the flow path. The cylindrical portion has an inner inner wall provided on the flow path side and an outer inner wall provided on the opposite side of the inner inner wall,
2. The heater according to claim 1, wherein a volume of a portion between the flow path and the inner inner wall of the main body is larger than a volume of an outer portion of the outer inner wall. An electrode connection plate is provided on an end surface of the sealing body,
The heater according to claim 1, wherein the electrode plates having the same polarity included in each of the plurality of heat generating units are connected in common to the electrode connection plate. The sealing body has a first sealing body provided on one end side in the longitudinal direction of the flow path, and a second sealing body provided on the other end side,
The negative electrode side electrode connection plate is provided on an end surface of the first sealing body, and a positive electrode side electrode connection plate is provided on an end surface of the second sealing body. 4. The heater according to 4. A compressor for compressing the refrigerant;
A heat exchanger in which the refrigerant compressed by the compressor is sent and the refrigerant is condensed;
An expansion valve through which the refrigerant condensed in the heat exchanger is sent and the refrigerant is expanded;
The heater according to claim 1, connected to a pipe between the compressor and the heat exchanger or between the heat exchanger and the expansion valve;
A heat pump system characterized by comprising:   The heater according to claim 1, wherein the main body is made of aluminum.

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