Heater

Abstract

To provide a heater which can prevent a heat medium from being boiled due to excessive heating.SOLUTION: An upper case 1 of a heater 100 has: an inlet pipe 11 into which a heat medium flows; and an outlet pipe 12 out of which the heat medium flows. A passage Fp for the heat medium is formed by assembling a lower case 2 to the upper case 1. The passage Fp consists of a plurality of branch passages fp in which end surfaces 15a of a plurality of fins 15 on the upper case 1 and end surfaces 22a of fins 22 on the lower case 2 face each other. An electric heater 3 is provided on a mounting surface 13a of the upper case 1, and an electric heater 4 is provided on a mounting surface 21a of the lower case.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a heater, and more particularly to a heater that heats a heat medium. [Background technology]

[0002] Japanese Patent Application Laid-Open Publication No. 2023-122813 (Patent Document 1) discloses a warm-up device for a secondary battery stack. This warm-up device has a heater that heats a heat medium. This heater includes a heat generator disposed in a container through which the heat medium passes. The heater is an electric heater that is made of a metal honeycomb formed from a conductive material with low heat capacity and generates heat when a voltage is applied. In the heater of Patent Document 1, heat is exchanged directly between the surface of the heat generator (electric heater) and the heat medium, causing the heat medium to change from a liquid to a vapor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-122813 Summary of the Invention [Problem to be solved by the invention]

[0004] In a warming device using a heat transfer medium, it may be desirable to perform warming without changing the state of the heat transfer medium from liquid to vapor. In this case, it is preferable to prevent excessive heating of the heat transfer medium in order to avoid boiling of the heat transfer medium.

[0005] An object of the present disclosure is to provide a heater that can prevent a heat medium from being excessively heated and boiling. [Means for solving the problem]

[0006] A heater according to the present disclosure is a heater for heating a heat medium. The heater includes a case that forms a flow path through which the heat medium flows. The case has a plurality of fins that protrude into the flow path and an installation surface that is formed on the opposite side of the flow path, and a heating unit is provided on the installation surface.

[0007] According to this configuration, the case has fins that protrude into the flow path through which the heat medium flows and an installation surface formed on the opposite side of the flow path. A heating unit is provided on the installation surface of the case. Heat from the heating unit is transferred to the heat medium via the case and the fins, and heat exchange occurs. Because the heat medium does not come into contact with the heating unit, it is possible to prevent the heat medium from overheating and boiling.

[0008] Preferably, the case includes a first case member having a plurality of first fins protruding therefrom and a second case member having a plurality of second fins protruding therefrom, and a flow path is formed in a space defined by the first case member and the second case member. At least one of the first case member and the second case member may be provided with a heating unit.

[0009] According to this configuration, the flow path can be formed relatively easily by assembling the first case member and the second case member. The heating unit may be provided in only one of the first case member or the second case member, or in both the first case member and the second case member.

[0010] Preferably, the heater further includes an inlet provided at one end of the case through which the heat medium flows in, and an outlet provided at the other end of the case through which the heat medium flows out. The flow path is formed from a plurality of branch flow paths formed such that an end face of a first fin protruding from the first case member faces an end face of a second fin protruding from the second case member. The branch flow path includes an outward path region connected to the inlet, a return path region connected to the outlet, and a reversal region at the other end of the case that connects the outward path region and the return path region. The distance between the end face of the first fin and the end face of the second fin at the boundary between the outward path region and the return path region may be shorter than the distance between the end face of the first fin and the end face of the second fin in other portions.

[0011] According to this configuration, the flow path through which the heat medium flows includes multiple branch flow paths. The multiple branch flow paths are formed by opposing end faces of first fins protruding from the first case member and second fins protruding from the second case member. The branch flow paths include an outward path region connected to an inlet provided at one end of the case, a return path region connected to an outlet provided at one end of the case, and a reversal region connecting the outward path region and the return path region at the other end of the case. The distance between the end face of the first fin and the end face of the second fin at the boundary between the outward path region and the return path region (this distance will also be referred to as distance Do) is shorter than the distance between the end face of the first fin and the end face of the second fin at other portions (this distance will also be referred to as distance Dt).

[0012] The heat medium that flows in from one end of the case flows through the forward region of the branch flow channels, reverses in the reversing region, flows through the return region, and flows out from one end of the case. At this time, at the boundary between the forward region and the return region, a portion of the heat medium flows from the branch flow channels in the forward region to the branch flow channels in the return region, reducing the amount of heat medium flowing through the reversing region. Because the distance Do is shorter than the distance Dt, the amount of heat medium flowing from the branch flow channels in the forward region to the branch flow channels in the return region can be reduced, and the reduction in the flow rate of the heat medium in the reversing region can be suppressed. Note that because the distance Dt is longer than the distance Do, the heat medium flows in the gap between the end faces of the first fin and the second fin, allowing heat exchange to occur at the end faces of the first fin and the second fin as well.

[0013] Preferably, the inlet and the outlet are provided in the first case member, and the first case member may be disposed vertically above.

[0014] With this configuration, the inlet and outlet are provided in the first case member, so the inlet and outlet can be smoothly connected to the flow path (branch flow path) of the first case member. Because the first case member is disposed vertically upward, air accumulation in the flow path of the heater can be reduced.

[0015] Preferably, the heating unit may be a sheet-like electric heater, and a central portion of the electric heater may be fixed to the installation surface. The case may include an engagement portion that abuts against a peripheral edge of the electric heater when the peripheral edge is separated from the installation surface.

[0016] According to this configuration, the heating unit is composed of a sheet-shaped electric heater. The center of the electric heater is fixed to the installation surface of the case, allowing expansion and contraction in the planar direction due to heat generated by the electric heater. When the peripheral edge of the electric heater moves away from the installation surface, an engagement portion provided on the case abuts against the peripheral edge of the electric heater, thereby suppressing warping of the electric heater. [Effects of the Invention]

[0017] According to the present disclosure, a heater can be provided that can prevent the heat medium from being overheated and boiling. [Brief explanation of the drawings]

[0018] [Figure 1] 1A and 1B are diagrams illustrating an outline of a heater according to the present embodiment. [Figure 2] FIG. 2 is a schematic exploded view of the heater. [Figure 3] 1A, 1B, and 1C are diagrams illustrating the configuration of a heater. [Figure 4] 1(B) and 2. FIG. 3 is a view of the upper case seen from the lower case side, taken along the arrow L in FIG. [Figure 5] FIG. 4 is a cross-sectional view taken along line VV of FIG. [Figure 6] FIG. 10 is a diagram illustrating a heater 100A according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, identical or corresponding parts are designated by the same reference numerals, and their description will not be repeated. The drawings are not drawn according to the actual dimensional ratio, and in some cases, the ratio is changed to clarify the structure in order to facilitate understanding of the structure. The embodiments and modifications described below may be combined as appropriate and selectively.

[0020] Fig. 1 is a diagram illustrating an overview of a heater 100 in this embodiment. Fig. 1(A) is a diagram illustrating one embodiment in which the heater 100 is used, and Fig. 1(B) is a perspective view of the heater 100. The heater 100 is used, for example, in a thermal management circuit Tm of an electric vehicle V. The thermal management circuit Tm includes a thermal circuit S and a refrigeration cycle R.

[0021] A refrigerant circulates in the refrigeration cycle R. The refrigeration cycle R includes a compressor R1 and a condenser R2. The high-pressure refrigerant discharged from the condenser R2 flows into the evaporator R3 via an electric expansion valve, and also flows into the chiller Ch via another electric expansion valve. The evaporator R3 is used as a cooling source for the air conditioning system of the electric vehicle V. The chiller Ch exchanges heat with the heat medium circulating in the thermal circuit S to cool the heat medium.

[0022] A heat medium circulates in the thermal circuit S. The thermal circuit S includes a three-way valve S1, a heater 100, a battery Bt, a reserve tank (R / T), an SPU (Smart Power Unit), a motor PCU (Power Control Unit), an oil cooler (O / C), and pumps W1 and W2. The battery Bt is, for example, an externally chargeable secondary battery, and is an energy source for driving an electric vehicle V. When the pump W1 is operated, ports P1 and P2 of the three-way valve S1 are connected, and the heat medium cooled by the chiller Ch circulates through the battery Bt, thereby cooling the battery Bt. When the pump W2 is operated, ports P2 and P3 of the three-way valve S1 are connected, and the heat medium heated by waste heat from the SPU, PCU, and O / C circulates through the battery Bt, thereby heating the battery Bt. In addition, the heater 100 heats the heat medium, thereby heating the battery Bt.

[0023] The heat medium circulating through the thermal circuit S may be, for example, insulating oil or insulating antifreeze liquid. As shown by the white arrows in Fig. 1(B), the heater 100 has a structure in which the heat medium flows in from an inlet pipe 11, flows through a flow path formed in a case (tank) 10, and then flows out from an outlet pipe 12. The case 10 is composed of an upper case (upper tank) 1 and a lower case (lower tank) 2.

[0024] Fig. 2 is a schematic exploded view of the heater 100. Fig. 3 is a diagram illustrating the configuration of the heater 100, and Fig. 3(A) is a top view of the heater 100. Fig. 3(B) is a bb-cross-sectional view of Fig. 3(A), and Fig. 3(C) is a cc-cross-sectional view of Fig. 3(A).

[0025] 2 and 3, a heat transfer medium flow path Fp is formed within the case 10 by assembling the lower case 2 to the upper case 1. The upper case 1 includes a bottom wall 13, a peripheral wall 14, and fins 15. The lower case 2 includes a bottom wall 21 and fins 22. A flange portion is formed on the peripheral wall 14 of the upper case 1, and this flange portion and the peripheral edge of the bottom wall 21 of the lower case 2 are fastened together using fastening bolts 8. In this embodiment, the lower case 2 is assembled to the upper case 1 by screwing nine fastening bolts 8 into female threads formed on the flange portion of the peripheral wall 14. A gasket 5 is provided between the flange portion of the peripheral wall 14 and the peripheral edge of the bottom wall 21 to maintain liquid-tightness of the flow path Fp.

[0026] A plurality of fins 22 protruding toward the flow path Fp are formed on the bottom wall 21 of the lower case 2. A plurality of fins 15 protruding toward the flow path Fp are formed on the bottom wall 13 of the upper case 1 (see FIGS. 3(B) and 3(C)). The upper case 1 corresponds to an example of a "first case member" in the present disclosure, and the fins 15 correspond to an example of a "first fin" in the present disclosure. The lower case 2 corresponds to an example of a "second case member" in the present disclosure, and the fins 22 correspond to an example of a "second fin."

[0027] End faces 15a of the multiple fins 15 are arranged opposite end faces 22a of the multiple fins 22. By arranging end faces 15a of fins 15 opposite end faces 22a of fins 22, branch flow paths fp of flow path Fp are formed in the space formed by fins 15 and fins 22. Flow path Fp for the heat medium is made up of multiple branch flow paths fp.

[0028] FIG. 4 is a view of the upper case 1 as seen from the lower case 2 side, and is a view taken along the arrow L in FIGS. 1(B) and 2. As shown in FIG. 4, the heat transfer medium flows in through an inlet pipe 11 formed at one end (the lower side in the figure) of the upper case 1 and flows out through an outlet pipe 12 formed at the other end (the lower side in the figure) of the upper case 1. The branch flow paths fp formed by the fins 15 (and fins 22) include an outward path area OA connected to the inlet pipe 11 and a return path area RA connected to the outlet pipe. The branch flow paths fp formed by the fins 15 (and fins 22) include a reversing area TA at the other end (the upper side in the figure) of the upper case 1. The branch flow paths fp in the reversing area TA connect the branch flow paths fp of the outward path area OA and the branch flow paths fp of the return path area RA.

[0029] As shown by the white arrows in Fig. 4, the heat transfer medium flowing in from the inlet pipe 11 flows through the branch flow paths fp in the forward area OA, then reverses at the branch flow paths fp in the reverse area TA, flows through the branch flow paths fp in the backward area RA, and flows out from the outlet pipe 12. The inlet pipe 11 corresponds to an example of an "inlet" in the present disclosure. The outlet pipe 12 corresponds to an example of an "outlet" in the present disclosure.

[0030] In the forward path area OA and the return path area RA, the fins 15 extend linearly from one end of the upper case 1 to the other. In the reversing area TA, the fins 15 extend in an arc shape to connect the forward path area OA and the return path area RA. In FIG. 4, the hatched fins 15 are fins at the boundary between the forward path area OA and the return path area RA. Referring to FIG. 3(C), the distance Do between the end face 15a of the fin 15 and the end face 22a of the fin 22 at the boundary between the forward path area OA and the return path area RA is set shorter than the distance Dt between the end face 15a of the fin 15 and the end face 22a of the fin 22 in other portions. Because the distance Do is set shorter than the distance Dt, the amount of heat transfer medium that takes a shortcut (bypass) from the forward path area OA to the return path area RA at the boundary between the forward path area OA and the return path area RA can be reduced, thereby suppressing a decrease in the heat transfer medium flow rate in the reversing area TA. In addition, since a small amount of heat medium takes a shortcut (bypass) from the forward area OA to the return area RA, heat is transferred from the electric heaters 3 and 4 described later in this section, thereby improving the heating efficiency of the heat medium.

[0031] 2 and 3, a mounting surface 13a on which the electric heater 3 is disposed is formed on the bottom wall 13 of the upper case 1, on the opposite side from the flow path Fp (branch flow path fp) (opposite the protruding direction of the fins 15). The electric heater 3 is a sheet-like electric heater (planar electric heater) that generates heat when electricity is applied. A substantially central portion of the electric heater 3 is fixed to the mounting surface 13a of the bottom wall 13 by a fixing bolt 6. A mounting surface 21a on which the electric heater 4 is disposed is formed on the bottom wall 21 of the lower case 2, on the opposite side from the flow path Fp (branch flow path fp) (opposite the protruding direction of the fins 22). The electric heater 4 is a sheet-like electric heater (planar electric heater) that generates heat when electricity is applied. A substantially central portion of the electric heater 4 is fixed to the mounting surface 21a of the bottom wall 21 by a fixing bolt 7.

[0032] A heat conductive member 31 may be applied between the electric heater 3 and the installation surface 13a formed on the bottom wall 13 of the upper case 1. A heat conductive member 41 may be applied between the electric heater 4 and the installation surface 21a formed on the bottom wall 21 of the lower case 2. This improves the efficiency of heat conduction between the upper case 1 and the electric heater 3 and between the lower case 2 and the electric heater 4. Heat conductive member 31 and heat conductive member 41 may be made of, for example, heat-dissipating silicon.

[0033] In the thermal circuit S, ports P2 and P3 of the three-way valve S1 are connected, and pump W2 is operated to circulate the heat medium through flow path Fp. When power is supplied to electric heaters 3 and 4 from an auxiliary battery (not shown) or a battery Bt, electric heaters 3 and 4 generate heat. The heat generated by electric heater 3 is transferred via heat conduction member 31, bottom wall 13, and fins 15 of upper case 1 to the heat medium flowing through branch flow path fp (flow path Fp), thereby heating the heat medium. The heat generated by electric heater 4 is transferred via heat conduction member 41, bottom wall 21, and fins 22 of lower case 2 to the heat medium flowing through branch flow path fp (flow path Fp), thereby heating the heat medium. The heat medium does not come into contact with electric heaters 3 and 4, and the heat from electric heaters 3 and 4 is transferred to the heat medium via the multiple fins 15 and fins 22. This prevents the heat medium from being overheated and boiling. In addition, because distance Dt is longer than distance Do, the heat medium flows through the gaps between end faces 15a of fins 15 and end faces 22a of fins 22 in the area excluding the boundary between forward region OA and backward region RA, and heat exchange can also occur between end faces 15a and 22a, making it possible to efficiently heat the heat medium.

[0034] The electric heater 3 is mounted on a mounting surface 13a formed on the bottom wall 13 of the upper case 1. The electric heater 3 is fixed at approximately its center to the mounting surface 13a (upper case 1) by a fixing bolt 6. The electric heater 3 expands in the planar direction when it generates heat due to the passage of electricity, and contracts in the planar direction when the passage of electricity is stopped and the temperature drops. Due to this expansion and contraction, the electric heater 3 may warp around its periphery.

[0035] FIG. 5 is a VV cross-sectional view of FIG. 1(A). The electric heater 3 is fixed at approximately its center to the installation surface 13a with a fixing bolt 6, but other portions of the electric heater 3 are able to expand and contract relative to the installation surface 13a, as indicated by the arrows in FIG. 5. Referring to FIG. 3(A), warp suppression bolts 9 are provided in the four corner regions of the periphery of the electric heater 3. The warp suppression bolts 9 are threaded into female threads formed on the periphery of the bottom wall 13 of the upper case 1. The head portion 91 of the warp suppression bolt 9 projects to a position facing the periphery of the electric heater 3, and a gap Gp is ​​formed between the periphery of the electric heater 3 and the head portion 91. When the periphery of the electric heater 3 warps, the periphery of the electric heater 3 comes into contact with the head portion 91, thereby suppressing warping of the electric heater 3. The umbrella portion 91 of the warp prevention bolt 9 corresponds to an example of the "engagement portion" of the present disclosure.

[0036] The fastening bolts 8 that fasten the lower case 2 to the upper case 1 also have an umbrella portion similar to the umbrella portion 91 of the warp prevention bolt 9. Then, with a configuration similar to that shown in Fig. 5, warping of the peripheral edge of the electric heater 4 is prevented. All of the fastening bolts 8 (nine fastening bolts 8) may have an umbrella portion to prevent warping of the peripheral edge of the electric heater 4, or the fastening bolts 8 arranged in the four corner regions of the peripheral edge of the electric heater 4 may have umbrella portions.

[0037] As shown in Figures 2 and 4, the inlet pipe 11 and the outlet pipe 12 are provided in the upper case 1. This allows the flow path of the inlet pipe 11 (and outlet pipe 12) to be smoothly connected (without forming a step) to the bottom wall of the upper case 1, as shown in Figure 3(B). A step (see P circled by a dashed line in Figure 3(B)) is formed between the inlet pipe 11 and the outlet pipe 12 and the lower case 2. This step may cause air to become trapped in the heat transfer medium.

[0038] In the thermal circuit S of this embodiment, the upper case 1 is disposed vertically upward. As a result, a step (see P circled by a dashed line in FIG. 3(B)) formed between the inlet pipe 11 and the outlet pipe 12 and the lower case 2 is disposed vertically downward, preventing air pockets from forming due to this step.

[0039] (Variation) FIG. 6 is a diagram illustrating a heater 100A according to a modified example. FIG. 6 is a cross-sectional view corresponding to FIG. 3(C) in the above embodiment. In the modified example, the upper case 1A includes a bottom wall 13A, a peripheral wall 14A, and fins 15A, as in the embodiment. In the modified example, the lower case 2A is composed of a bottom wall 21A. In the modified example, the lower case 2A does not include fins. In the modified example, a flange portion provided on the peripheral wall 14A of the upper case 1A and a peripheral edge portion of the bottom wall 21A of the lower case 2A are fastened together using fastening bolts.

[0040] In this modification, a flow path Fp (branch flow path fp) is formed in the space formed by the fins 15A of the upper case 1A and the bottom wall 21A of the lower case 2A. An electric heater 3 is disposed on the installation surface of the upper case 1A, but no electric heater is disposed in the lower case 2A.

[0041] In this modification, when the electric heater 3 is energized, the electric heater 3 generates heat. The heat generated by the electric heater 3 is transferred to the heat medium flowing through the branch flow path fp (flow path Fp) via the bottom wall 13A and fins 15A of the upper case 1A, and the heat medium is heated. The heat medium does not come into contact with the electric heater 3, and the heat from the electric heater 3 is transferred to the heat medium via the multiple fins 15A. This prevents the heat medium from being overheated and boiling. Note that in this modification, no heat conductive material is applied between the electric heater 3 and the bottom wall 13A, but a heat conductive material may be applied as in the above embodiment.

[0042] In the above embodiment, an electric heater is used to heat the heat medium. However, any heat source capable of heating the heat medium may be used, and is not limited to an electric heater. Also, in the above embodiment, the end faces 15a of the fins 15 of the upper case 1 and the end faces 22a of the fins 22 of the lower case 2 are arranged to face each other. However, the end faces 15a and 22a may be arranged not to face each other, except at the boundary between the outward path area OA and the return path area RA.

[0043] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0044] 1,1A upper case, 10 case, 11 inlet pipe, 12 outlet pipe, 13 bottom wall, 13a installation surface, 14 peripheral wall, 15 fin, 15a end surface, 2,2A lower case, 21 bottom wall, 21a installation surface, 22 fin, 22a end surface, 3 electric heater, 31 heat conduction member, 4 electric heater, 41 heat conduction member, 100 heater, Fp flow path, fp branch flow path, OA forward region, RA return region, TA reversal region.

Claims

1. A heater for heating a heat medium, a case that forms a flow path through which the heat transfer medium flows, The case is a plurality of fins protruding into the flow path; an installation surface formed on the opposite side of the flow path, A heater having a heating section provided on the installation surface.

2. the case includes a first case member from which a plurality of first fins protrude and a second case member from which a plurality of second fins protrude, and the flow path is formed in a space defined by the first case member and the second case member; The heater according to claim 1 , wherein the heating portion is provided in at least one of the first case member and the second case member.

3. an inlet provided on one end side of the case and through which the heat medium flows; a discharge port provided on the one end side of the case and through which the heat medium flows out, the flow path is composed of a plurality of branch flow paths formed such that an end face of the first fin protruding from the first case member and an end face of the second fin protruding from the second case member face each other, The branch flow path is an outflow area connected to the inlet; a return path region connected to the discharge port; a reversal region connecting the outward path region and the return path region at the other end of the case, 3. The heater of claim 2, wherein the distance between the end face of the first fin and the end face of the second fin at the boundary between the outward region and the return region is shorter than the distance between the end face of the first fin and the end face of the second fin in other portions.

4. the inlet and the outlet are provided in the first case member, The heater according to claim 3 , wherein the first case member is disposed vertically upward.

5. the heating unit is a sheet-shaped electric heater, a central portion of the electric heater is fixed to the installation surface; The heater according to claim 1 , wherein the case includes an engaging portion that comes into contact with a peripheral edge of the electric heater when the peripheral edge of the electric heater moves away from the installation surface.

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