JP2017091983A - Exhaust system for air cooling of on-vehicle battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively use exhaust after cooling of a battery, the exhaust having been only wasted in the past.SOLUTION: An exhaust system 10 includes an exhaust duct 26 for discharging exhaust after cooling of a battery 12. A downstream side of the exhaust duct 26 is branched into a first exhaust path 32 (luggage side exhaust path) having an exhaust port directed to a luggage space 34 and a second exhaust path 36 (glass side exhaust path) having an exhaust port directed to rear glass 38. A switching valve 28 is provided at a branch point of the exhaust duct 26, the switching valve opening the second exhaust path 36 when it is determined that condensation is formed on the rear glass 38.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an exhaust device that exhausts exhaust air after cooling a battery provided under a rear seat of a vehicle.

  In a hybrid vehicle, an electric vehicle, or the like, a battery and a cooling mechanism for the battery are provided under the rear seat of the vehicle. The cooling mechanism includes a blower that takes in the cooling air in the vehicle interior, an air supply duct that sends the taken cooling air to the battery, and an exhaust duct that discharges the exhaust after cooling. For example, in Patent Document 1, the exhaust port of the exhaust duct is directed to the luggage space, and the exhaust is discarded in this space.

Japanese Patent Laying-Open No. 2015-85874

  By the way, in order to improve energy efficiency, there is a need for effective use of exhausted air after battery cooling that is conventionally discarded.

  The present invention relates to an in-vehicle battery air-cooling exhaust device that exhausts exhaust air after cooling a battery provided under a vehicle rear seat. The apparatus includes an exhaust duct that exhausts exhausted air after cooling the battery. The downstream side of the exhaust duct is branched into a first exhaust path having an exhaust port directed to the luggage space and a second exhaust path having an exhaust port directed to the rear glass. A valve that opens the second exhaust passage when it is determined that condensation occurs on the rear glass is provided at a branch point of the exhaust duct.

  According to the present invention, exhaust after cooling the battery, which is conventionally discarded, can be effectively used as means for eliminating condensation on the rear glass.

It is a figure which illustrates the main structures of a vehicle by which the exhaust apparatus for vehicle-mounted battery air cooling which concerns on this embodiment is mounted. It is a side view which illustrates the back seat periphery of vehicles. It is a flowchart which illustrates a rear glass dew condensation determination flow. It is a figure at the time of throwing away exhaust_gas | exhaustion in luggage space. It is a figure at the time of sending exhaust_gas | exhaustion to a rear glass.

  FIG. 1 shows a main configuration of a vehicle including an exhaust device 10 (exhaust duct 26, switching valve 28 and control unit 42) for in-vehicle battery air cooling according to the present embodiment. 1 represents a signal line. FIG. 2 illustrates a side view of the rear side of the vehicle. The vehicle shown in FIG. 2 is an electric vehicle or a hybrid vehicle equipped with a battery 12 as a power source.

  The battery 12 includes a secondary battery such as a nickel metal hydride battery or a lithium ion battery. As shown in FIG. 2, the battery 12 is provided below the rear seat 14 of the vehicle.

  As shown in FIG. 1, the DC power of the battery 12 is boosted by a step-up / step-down DC / DC converter 16 and further orthogonally converted by an inverter 18. The converted AC power is supplied to the rotating electrical machine 20. Further, at the time of regeneration of the rotating electrical machine 20, regenerative power is AC / DC converted by the inverter 18 and further stepped down by the step-up / step-down DC / DC converter 16. The DC power after the step-down is supplied to the battery 12.

  1 and 2 illustrate a cooling mechanism (air cooling mechanism) of the battery 12. The cooling mechanism includes a battery cooling blower 22, an air supply duct 24, an exhaust duct 26, and a switching valve 28. The battery cooling blower 22 and the air supply duct 24 are provided in the lower part of the rear seat 14 similarly to the battery 12. Among the cooling mechanisms, the exhaust duct 26, the switching valve 28, and the control unit 42 that controls the driving of the switching valve 28 are included in the exhaust device 10 according to the present embodiment.

  As shown in FIG. 1, the step-down DC / DC converter 30 connected to the battery 12 reduces the DC power of the battery 12 to a predetermined auxiliary voltage. The motor of the battery cooling blower 22 is driven by the stepped down electric power, whereby the battery cooling blower 22 takes in the air (cooling air) in the vehicle interior. When the step-down DC / DC converter 30 is not operating, such as when the ignition is off, the battery cooling blower 22 can be driven by receiving power supply from the auxiliary battery 27.

  Cooling air taken in by the battery cooling blower 22 is sent to the battery 12 through the air supply duct 24. The battery 12 is accommodated in the case 29, and the downstream port of the air supply duct 24 is connected to the air supply side connection port 31 of the case 29. An upstream port of the exhaust duct 26 is connected to the exhaust side connection port 33 of the case 29. The exhaust after cooling the battery 12 flows from the case 29 into the exhaust duct 26. The temperature of the exhaust is, for example, about 40 ° C.

  As shown in FIG. 2, the downstream side of the exhaust duct 26 is bifurcated. One of the branched exhaust passages 32 (luggage side exhaust passage, first exhaust passage) has an exhaust port directed to the luggage space 34, and the other exhaust passage 36 (glass side exhaust passage, second exhaust passage). The exhaust port is directed to the rear glass 38 (rear door glass) on the side of the rear seat 14. The exhaust port of the glass side exhaust path 36 is preferably close to the rear glass 38 and is provided, for example, behind the uppermost part of the seat back (backrest) of the rear seat 14.

  A switching valve 28 is provided at the branch point of the exhaust duct 26. The switching valve 28 opens one of the luggage side exhaust passage 32 and the glass side exhaust passage 36 and closes the other. The switching valve 28 is constituted by a ball valve, for example. As will be described later, by controlling the switching valve 28, the glass-side exhaust path 36 can be opened to send exhaust to the rear glass 38. Thereby, the condensation of the rear glass 38 can be eliminated by utilizing the heat of the exhaust. In addition, from the viewpoint of heat utilization of the exhaust, the glass side exhaust path 36 may have a heat insulating structure.

  Returning to FIG. 1, the control unit 42 may be configured by a computer, and a calculation unit 44, a storage unit 46, and a device / sensor interface (not shown) are connected to each other via an internal bus.

  The control unit 42 receives signals from various sensors and switches via the device / sensor interface. Specifically, the temperature Tb of the battery 12 is received from the battery temperature sensor 48. Further, the voltage across the battery 12 and the current flowing through the battery 12 are received from a voltage sensor and a current sensor (not shown).

  In addition, the control unit 42 receives the vehicle interior temperature Ti from the vehicle interior temperature sensor 50 and the vehicle exterior temperature To from the vehicle exterior temperature sensor 52. Further, an on / off signal is received from an air conditioner switch 54, an outside air introduction switch 56, and an air conditioner switch 58 provided on an instrument panel (not shown) of the passenger compartment.

  Upon receiving these received signals, the control unit 42 controls various devices of the vehicle. For example, on / off control of switching elements (not shown) of the step-up / step-down DC / DC converter 16 and the inverter 18 is performed based on a drive request to the rotating electrical machine 20. Further, in order to step down the voltage of the battery 12 to the auxiliary machine voltage, on / off control of a switching element (not shown) of the step-down DC / DC converter 30 is performed. Further, when an ON signal of the air conditioner switch 54 or the air conditioner switch 58 is received, the air conditioner blower motor 60 is driven.

  Further, when the temperature Tb of the battery 12 received from the battery temperature sensor 48 reaches a predetermined high temperature range, the battery cooling blower 22 is driven to cool the battery 12.

  In addition, the control unit 42 controls the switching valve 28 based on a rear glass dew condensation determination flow, which will be described later, and switches the open / close state of the luggage side exhaust path 32 and the glass side exhaust path 36. The rear glass condensation determination flow is stored in the storage unit 46 of the control unit 42.

<Rear glass condensation judgment flow>
FIG. 3 illustrates a rear glass dew condensation determination flow according to the present embodiment. In this flow, whether or not the rear glass 38 is condensed is determined. When it is determined that the condensation has occurred, the luggage side exhaust path 32 is closed and the glass side exhaust path 36 is opened, and the exhaust is sent to the rear glass 38. The rear glass 38 is warmed by the heat of the exhaust, and condensation is eliminated.

  As described above, in the present embodiment, condensation on the rear glass 38 is eliminated by using the exhaust gas after the battery 12 is cooled. As a matter of course, exhaust is not generated during cooling of the battery 12, that is, when the cooling blower 22 is not operated. From this, the rear glass dew condensation determination flow is started with a drive command for the battery cooling blower 22 as a trigger.

  The control unit 42 monitors the temperature Tb of the battery 12 from the battery temperature sensor 48, and drives the battery cooling blower 22 when it reaches a predetermined high temperature range. The rear glass dew condensation determination flow starts with the output of this drive command. The control unit 42 acquires the vehicle outside temperature To from the vehicle outside temperature sensor 52 (S10). Next, the controller 42 determines whether or not the acquired outside temperature To is less than a predetermined threshold temperature To_th (S12). Since condensation occurs in a cold season such as winter, it is determined in step S12 whether or not the outside of the vehicle is cold.

  When the outside temperature To is equal to or higher than the threshold temperature To_th in step S12 (when the outside of the vehicle is not so cold), the control unit 42 drives the switching valve 28 and, as shown in FIG. And the glass-side exhaust path 36 (second exhaust path) is closed (S14). On the other hand, when the vehicle exterior temperature To is lower than the threshold temperature To_th in step S12, the control unit 42 acquires the vehicle interior temperature Ti from the vehicle interior temperature sensor 50 (S16). Further, the control unit 42 determines whether or not the difference (Ti−To) between the passenger compartment temperature Ti and the vehicle exterior temperature To exceeds a predetermined threshold value ΔT_th (S18). When the interior of the vehicle is warm and the outside of the vehicle is cold, the warm interior air around the window glass is cooled to the outside air, causing condensation. From this, in step S18, the temperature difference inside and outside the vehicle is determined.

  When the difference (Ti−To) between the passenger compartment temperature Ti and the vehicle exterior temperature To is less than or equal to the predetermined threshold value ΔT_th in step S18, that is, when the temperature difference between the vehicle interior and exterior is small, the control unit 42 drives the switching valve 28, The luggage side exhaust path 32 (first exhaust path) is opened, and the glass side exhaust path 36 (second exhaust path) is closed (S14). On the other hand, when the difference between the vehicle interior temperature Ti and the vehicle exterior temperature To (Ti−To) exceeds a predetermined threshold value ΔT_th, the control unit 42 refers to the on / off state of the outdoor air introduction switch 56 and the vehicle interior air conditioning is It is determined whether or not the circulation mode is set (S20).

  In the case of No in step S20, that is, when the air conditioning is in the outside air circulation mode, the generation of condensation is avoided because the outside air having a low humidity (dry) is introduced. Therefore, the control unit 42 drives the switching valve 28 to open the luggage side exhaust path 32 (first exhaust path) and close the glass side exhaust path 36 (second exhaust path) (S14).

  When the vehicle interior air conditioning is in the internal circulation mode, the control unit 42 refers to the on / off status of the air conditioner switch 54 to determine whether the air conditioner system is in operation (S22). When the air conditioner system is in operation, the dehumidification function eliminates condensation, so the control unit 42 drives the switching valve 28 to open the luggage side exhaust path 32 (first exhaust path) and the glass side exhaust path. 36 (second exhaust passage) is closed (S14).

  When the air conditioner system is in an off state, the control unit 42 determines that condensation has occurred on the rear glass 38 based on the determination results of steps S12 to S20 so far. At this time, the controller 42 drives the switching valve 28 to close the luggage side exhaust path 32 (first exhaust path) and to close the glass side exhaust path 36 (second exhaust path) as shown in FIG. Is opened (S24). As a result, exhaust gas is sent from the glass side exhaust passage 36 to the rear glass 38 to warm the rear glass 38, and condensation is eliminated.

  As described above, in the exhaust device 10 for air cooling of the on-vehicle battery according to the present embodiment, the exhaust after the cooling of the battery 12 is used, in other words, the exhaust heat generated when the battery 12 is cooled is used. Condensation is eliminated. Further, when no condensation occurs on the rear glass 38, the exhaust gas is discarded into the luggage space 34 as usual. Accordingly, it is possible to avoid the so-called “haze” in which hot air is accumulated around the head of the occupant of the rear seat 14 and the discomfort is caused although no condensation occurs.

  In the above-described embodiment, the opening / closing control of the switching valve 28 is performed based on the determination of the control unit 42, but the present invention is not limited to this. For example, the opening / closing control of the switching valve 28 may be performed by a button operation of a driver or an occupant.

  In the above-described embodiment, the exhaust duct 26 is branched and the exhaust port is extended to the rear door glass. However, the present invention is not limited to this configuration. For example, the exhaust duct 26 may be branched to extend the exhaust port to the back door glass to eliminate condensation on the glass.

  DESCRIPTION OF SYMBOLS 10 Exhaust device, 12 Battery, 14 Back seat, 22 Battery cooling blower, 24 Air supply duct, 26 Exhaust duct, 28 Switching valve, 32 Luggage side exhaust path (1st exhaust path), 34 Luggage space, 36 Glass side exhaust Road (second exhaust path), 38 rear glass, 42 control unit, 48 battery temperature sensor, 50 compartment temperature sensor, 52 outside temperature sensor, 54 air conditioner switch, 56 outside air introduction switch, 58 air conditioning switch.

Claims (1)

An exhaust system for vehicle-mounted battery air cooling that exhausts exhaust air after cooling a battery provided under a vehicle rear seat,
An exhaust duct for discharging exhaust air after cooling the battery;
The downstream side of the exhaust duct is branched into a first exhaust path having an exhaust port directed to the luggage space and a second exhaust path having an exhaust port directed to the rear glass,
An on-vehicle battery air-cooling exhaust apparatus, wherein a branching point of the exhaust duct is provided with a valve that opens the second exhaust path when it is determined that condensation occurs on the rear glass.

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