JP2021024296A - vehicle - Google Patents

Abstract

To inhibit a delay in start timing of cooling of peripheral components to inhibit heat damage of the peripheral components caused by radiation heat from a filter device when an operation mode of the filter device is switched.SOLUTION: A vehicle 1 includes: an engine 10; a filter device 30 which captures particulate matters contained in exhaust gas discharged from the engine 10; a cover 50 which covers the engine 10 and the filter device 30; a cooling mechanism 70 which sends outside air to a periphery of the filter device 30 to cool the filter device 30; and a control part 80 which controls the cooling mechanism 70. The control part 80 controls cooling operation of the cooling mechanism 70 based on switch timing of an operation mode of the filter device 30.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vehicle.

For example, Patent Document 1 discloses that the engine is covered with a cover to form a capsule structure in order to control the heat of the engine room and reduce the sound emitted from the engine room to the outside of the vehicle. In the technique described in Patent Document 1, when the capsule structure is provided with two or more ventilation ports including a front inlet and a rear outlet and an air flap for opening and closing the front inlet, and the air flap is opened. The engine inside the capsule structure is cooled by introducing air from the front inlet and discharging it from the rear outlet.

Further, in recent years, a filter device for a vehicle such as a GPF (Gasoline Particulate Filter) has been developed in order to remove particulate matter such as soot and oil-derived ash contained in exhaust gas. If this filter device is used continuously, soot or the like may accumulate on the filter that captures particulate matter and cause clogging. Therefore, in order to regenerate the clogged filter, the operation mode of the filter device is switched from the normal mode to the regeneration mode, and the particulate matter such as accumulated soot is forcibly burned and removed (forced ascending). Warm treatment) is carried out. In this regeneration mode, the filter device in the capsule structure rises to a high temperature, which may cause heat damage to peripheral parts of the filter device.

Regarding the temperature control of the exhaust system, for example, in Patent Document 2, the exhaust system is opened and closed by opening and closing the openings of the grill shutter and the undercover based on the temperature (catalyst temperature) of the exhaust system catalyst arranged in the engine room. It is disclosed to control the temperature of the catalyst. Further, Patent Document 3 discloses that when the temperature of the rear atmosphere of the engine is higher than the reference value, the air flow path of the duct is opened by the air volume regulator, and the catalyst device is cooled by the air flow from the duct. ing.

Japanese Unexamined Patent Publication No. 2013-119384 JP-A-2018-30429 International Publication No. 2017/170432 Pamphlet

However, as described in Patent Documents 2 and 3, the method of starting the cooling operation of the exhaust system by using the measured temperature such as the catalyst temperature or the temperature of the rear atmosphere of the engine as a trigger causes the ambient temperature of the exhaust system to rise. The cooling operation will be started after the temperature actually rises. Therefore, the start of the cooling operation is delayed from the appropriate timing. Therefore, when the filter device such as GPF switches to the regeneration mode and the catalyst temperature in the filter device rises rapidly to a high temperature (for example, about 900 ° C.), the ambient temperature rises to the allowable temperature or higher due to the radiant heat from the filter device. As a result, peripheral parts of the filter device may be damaged by heat.

Therefore, an object of the present invention is to suppress a delay in the cooling start timing when switching the operation mode of the filter device, and to suppress heat damage to peripheral parts due to radiant heat from the filter device.

In order to solve the above problems, according to a certain aspect of the present invention, an engine, a filter device for capturing particulate matter contained in exhaust gas discharged from the engine, a cover covering the engine and the filter device, and outside air. The cooling mechanism is provided with a cooling mechanism for cooling the filter device and a control unit for controlling the cooling mechanism. The control unit is operated by the cooling mechanism based on the switching timing of the operation mode of the filter device. A vehicle is provided that controls the cooling operation.

The operation mode of the filter device includes a regeneration mode for burning and removing particulate matter accumulated inside the filter device, and the control unit cools the operation mode of the filter device according to the timing of switching to the regeneration mode. The cooling operation by the mechanism may be started.

The control unit may end the cooling operation by the cooling mechanism according to the timing of ending the reproduction mode.

The control unit may terminate the cooling operation by the cooling mechanism based on the temperature associated with the operation of the filter device.

The control unit may switch the operation mode of the filter device based on the pressure difference between the exhaust gas introduced into the filter device and the exhaust gas discharged from the filter device.

The cooling mechanism includes an opening that communicates the outside air with the internal space of the cover, an opening / closing device that opens / closes the opening, and an outside air flow path that guides the outside air flowing in from the opening to the periphery of the filter device. The unit may open and close the opening by the opening / closing device based on the switching timing of the operation mode of the filter device.

The opening is an opening formed in the undercover of the vehicle, and the opening / closing device may be a valve for opening / closing the opening.

The opening / closing device is a grill shutter provided on the front of the vehicle, and the opening may be an opening provided in the grill shutter.

According to the present invention, when the operation mode of the filter device is switched, the delay of the cooling start timing can be suppressed, and the heat damage of peripheral parts due to the radiant heat from the filter device can be suppressed.

It is the schematic which shows the structure of the vehicle which concerns on 1st Embodiment of this invention. It is a timing chart which shows the switching timing of the operation mode of GPF which concerns on this embodiment, and the opening and closing timing of an opening by a cooling mechanism. It is a timing chart which shows the switching timing of the operation mode of GPF which concerns on 2nd Embodiment of this invention, and the opening / closing timing of an opening by a cooling mechanism.

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The dimensions, materials, other specific numerical values, and the like shown in the embodiment are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are designated by the same reference numerals to omit duplicate description, and elements not directly related to the present invention are not shown. To do.

[1. Vehicle configuration]
First, the configuration of the vehicle 1 according to the first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic view showing the configuration of the vehicle 1 according to the present embodiment.

In this embodiment, an example in which the vehicle 1 is a vehicle having only an engine as a power source will be described. However, the present invention is not limited to such an example, and can be applied to a hybrid vehicle having both an engine and a motor as a power source.

As shown in FIG. 1, the vehicle 1 includes an engine 10, a transmission 20, a filter device (for example, GPF30), a cover 50 (upper cover 52, undercover 54), a floor panel 56, and a cooling mechanism 70. , The control unit 80 is provided. In addition to these devices, the vehicle 1 includes drive mechanisms such as differential gears, drive shafts, and drive wheels, operating devices, radiators, oil pumps, various sensors, auxiliary devices (for example, air conditioning equipment or acoustic equipment), and the like. , It is provided with various devices or parts mounted on a vehicle, but is not shown in FIG.

The engine 10 is an internal combustion engine that burns fuel such as gasoline or light oil to generate power for driving the vehicle 1. The power output from the engine 10 is used, for example, to drive the drive wheels of the vehicle 1. The engine 10 is arranged in an engine room 3 provided in the front portion of the vehicle 1. The engine room 3 is a space in the vehicle 1 on the front side of the vehicle room 2. The vehicle compartment 2 and the engine compartment 3 are partitioned by structural members such as a toe board (not shown). Further, the lower side of the vehicle interior 2 is partitioned by a floor panel 56.

The transmission 20 converts the torque, rotation speed, and the like of the rotational power transmitted from the engine 10 and transmits the converted rotational power to the output shaft. The transmission 20 may be, for example, a multi-stage reduction mechanism or a continuously variable transmission (CVT). The transmission 20 transmits the reduced rotational power to the drive wheels via, for example, a differential gear and a drive shaft (not shown). In this way, the vehicle 1 travels by the driving force generated by the engine 10.

The GPF 30 is an example of a filter device, and is mounted on a vehicle 1 that uses gasoline as fuel. A filter device such as the GPF 30 is a processing device for purifying the exhaust gas discharged from the engine 10, and has a function of capturing and removing particulate matter contained in the exhaust gas discharged from the engine 10.

Exhaust gas generated by burning fuel in the combustion chamber of the engine 10 is discharged to an exhaust system arranged after the engine 10 through an exhaust passage 32. Since the exhaust gas contains hydrocarbons (HC: Hydro Carbon), carbon monoxide (CO), nitrogen oxides (NOx), and particulate matter (PM: Particulate Matter), it is necessary to remove them. Therefore, a three-way catalyst and a filter device are installed in the middle of the exhaust passage 32, hydrocarbons, carbon monoxide, and nitrogen oxides are removed by the three-way catalyst, and particulate matter is removed by the filter device.

The three-way catalyst (Three-Way Catalyst) is a catalyst provided in the exhaust passage 32. The three-way catalyst is composed of a carrier carrying, for example, platinum (Pt), palladium (Pd), and rhodium (Rh), and removes hydrocarbons, carbon monoxide, and nitrogen oxides in the exhaust gas. The filter device is provided on the downstream side of the three-way catalyst in the exhaust passage 32, and filters and captures particulate matter in the exhaust gas. The particulate matter is, for example, fine particles such as soot of fuel (for example, carbide) left unburned in the engine 10 and oil-derived ash.

The GPF 30 according to the present embodiment is composed of a processing device in which the three-way catalyst and a filter device are integrated, and has an added purification function of the three-way catalyst. However, the present invention is not limited to this, and the three-way catalyst and the filter device may be configured by separate devices.

The GPF 30 is composed of, for example, a wall flow type filter device. The wall flow type filter device has a plurality of cells partitioned by a filter wall in which a plurality of pores through which the exhaust gas passes are formed, and the particulate matter in the exhaust gas is captured by the fine pore structure of the filter wall. Gather.

The GPF 30 is provided in the middle of the exhaust passage 32 for discharging the exhaust gas discharged from the engine 10 to the outside of the vehicle. The exhaust passage 32 includes an exhaust pipe that connects an exhaust port of the engine 10 and a muffler (not shown) that discharges exhaust gas to the outside of the vehicle. The exhaust gas discharged from the engine 10 is introduced into the GPF 30 through the exhaust passage 32, and is purified by the catalyst function and the filter function of the GPF 30. Further, the exhaust gas purified by the GPF 30 is introduced into the muffler on the downstream side through the exhaust passage 32 and discharged to the outside of the vehicle.

By the way, the particulate matter collected by GPF30 is deposited in the pores of the filter wall over time. As a result, problems such as clogging of the filter, deterioration of the collection performance of particulate matter, and pressure loss of exhaust gas occur.

Therefore, it is necessary to raise the temperature inside the GPF 30 to a high temperature and perform a regeneration process of burning and removing the particulate matter deposited on the filter wall of the GPF 30 at a high temperature. In the regeneration process, outside air is supplied to the exhaust passage 32 to forcibly raise the temperature of the filter portion in the GPF 30, and mainly among the particulate matter (soot and ash) trapped and deposited on the filter wall of the GPF 30. This is a process of burning and removing soot (forced temperature rise process). By performing such a regeneration treatment, the filter wall clogged with soot can be regenerated, so that the GPF 30 can again suitably collect particulate matter.

Next, the capsule structure provided in the vehicle 1 according to the present embodiment will be described with reference to FIG.

The capsule structure is a structure for covering the periphery of the power unit (for example, the engine 10, the transmission 20, the GPF 30, etc.) provided in the vehicle 1. This capsule structure mainly has a soundproofing function that blocks the sound generated from the power unit and a temperature control function that cools or keeps the power unit warm, but in addition to that, it has a function of protecting the power unit, a dustproof function, or a waterproof function. And so on.

A power unit is a device that generates heat as it operates, and is a device to be cooled. In this embodiment, an example in which the power unit is an exhaust gas treatment device such as an engine 10, a transmission 20, and a GPF 30 will be described. However, the power unit is not limited to such an example, and the power unit may be any device mounted on the vehicle 1 as long as it is a device that requires soundproofing or temperature control, or a device provided incidentally to the device.

As shown in FIG. 1, the capsule structure according to the present embodiment includes a cover 50 including an upper cover 52 and an under cover 54. The upper cover 52 is a cover member provided on the upper side of the engine room 3 and covering at least the upper surface side of the power unit. The upper cover 52 according to the present embodiment has a structure that covers not only the upper surface side of the power unit but also a part or all of the left and right side surfaces, the front surface, and the rear surface side.

As the material of the upper cover 52, a metal such as aluminum, titanium, steel, or a synthetic resin can be used. In order to improve the soundproofing property of the upper cover 52, the upper cover 52 may be formed of a soundproofing material, or a sound absorbing member formed of a sound absorbing material may be attached to the inside of the upper cover 52. .. As the sound absorbing material, various materials such as glass wool, rock wool, urethane foam, felt, asbestos board, and wood wool board that attenuate the energy of sound as it passes through can be used.

The upper cover 52 may be composed of one cover member or a combination of a plurality of cover members. Further, the upper cover 52 may be an engine cover installed in the engine room 3, or may be a cover member installed separately from the engine cover. Further, the front portion of the floor panel 56 may be extended and used as the upper cover 52. In this way, the floor panel 56 and the upper cover 52 may be integrally configured, or as shown in FIG. 1, both may be configured as separate members.

The undercover 54 is a cover member that covers the bottom of the vehicle 1. The undercover 54 covers the bottom surface side of the power unit. As the material of the undercover 54, a metal such as aluminum, titanium, steel, or a synthetic resin can be used.

As described above, in the capsule structure of the present embodiment, the upper and lower covers (upper cover 52 and under cover 54) are combined to cover almost the entire circumference of the power unit. Therefore, the periphery of the exhaust system such as the engine 10, the transmission 20, and the GPF 30 is covered with the cover 50 and is substantially sealed. Therefore, since the sound generated from these devices can be blocked by the cover 50, the soundproofing property can be improved.

The shape of the cover 50 may be any shape as long as it can cover the periphery of the necessary parts of the power unit. Further, from the viewpoint of improving airtightness and soundproofing, it is preferable not to provide an opening in the cover 50 of the capsule structure as much as possible, but an opening for ventilation or device connection is formed in a part of the cover 50. You may be. Further, one side or a plurality of sides of the capsule structure may be open. Further, the structure may cover the power unit by connecting the cover 50 with another member (for example, a structural member) constituting the vehicle 1.

The cooling mechanism 70 cools the filter device by sending air outside the cover 50 (for example, outside air outside the vehicle 1) to the periphery of the filter device (GPF30). Since the power unit has a capsule structure as described above and is covered by the cover 50, it is desirable to control the temperature of the installation space of the power unit. Therefore, the cooling mechanism 70 introduces outside air around the power unit arranged in the internal space of the cover 50 (for example, the engine room 3) to air-cool the power unit and its peripheral parts. Details of the configuration of the cooling mechanism 70 will be described later.

The control unit 80 controls each device provided in the vehicle 1. The control unit 80 is composed of, for example, a semiconductor integrated circuit equipped with a processor, a storage element, and the like. The control unit 80 may be physically composed of one electronic control unit (ECU: Electronic Control Unit). Alternatively, the control unit 80 may be composed of a plurality of ECUs (for example, an engine ECU, a motor ECU, a transmission ECU, etc.), and the control function of the control unit 80 may be shared by the plurality of ECUs. The ECU is a central processing unit (CPU: Central Processing Unit), a ROM (Read Only Memory) that stores programs and arithmetic parameters used by the CPU, and a RAM (RAM) that temporarily stores parameters that change appropriately in arithmetic processing by the CPU. Random Access Memory) and the like may be provided. The control unit 80 can communicate with each device by using, for example, CAN (Control Area Network) communication in order to control each device to be controlled mounted on the vehicle 1.

The control unit 80 according to the present embodiment controls the operation of the filter device (for example, GPF 30) and the cooling mechanism 70. In particular, the control unit 80 is characterized in that the cooling operation by the cooling mechanism 70 is controlled based on the switching timing of the operation mode of the filter device. The details of this control method will be described later.

[2. Cooling mechanism configuration and cooling operation]
Next, with reference to FIG. 1, the configuration of the cooling mechanism of the capsule structure according to the present embodiment will be described in more detail.

As described above, in order to clear the clogging of the filter portion in the GPF 30 and regenerate the filter, the temperature inside the GPF 30 is forcibly raised to burn and remove the fine particles of soot accumulated on the filter. Is executed. During this regeneration process, the catalyst has a high temperature of, for example, about 900 ° C., so that heat damage to peripheral parts of the GPF 30 becomes a problem. Here, peripheral parts that are susceptible to heat damage by the GPF 30 include, for example, an electric oil pump (EOP: Electrically operated Oil Pump), a soundproof cover such as an upper cover 52, and a mount portion (rubber portion) of various devices such as a transmission 20. And so on.

In particular, the vehicle 1 according to the present embodiment has a capsule structure in which a heat generating device such as an engine 10, a transmission 20, and a GPF 30 is covered with a cover 50 (upper cover 52 and undercover 54). For this reason, the heat of these heat generating devices tends to be trapped in the internal space (engine room 3, etc.) of the cover 50, so that heat damage to peripheral parts of the GPF 30 is likely to occur. Therefore, it is preferable to provide a cooling mechanism for cooling the internal space of the cover 50 to cool the GPF 30 and its peripheral parts to suppress heat damage to the peripheral parts. As this cooling mechanism, from the viewpoint of simplification of the device configuration and cost reduction, an opening serving as a vent is provided in the cover 50, and outside air is introduced into the cover 50 from the opening to introduce the device in the cover 50. An air-cooled mechanism is preferred.

On the other hand, if a large number of openings are formed in the cover 50 or the opening area is increased, the soundproofing property of the capsule structure is lowered. Therefore, it is preferable to intermittently cool the space inside the cover 50 at an appropriate timing as needed, instead of constantly cooling the space. As a result, it is possible to achieve both measures against heat damage to peripheral parts of the GPF 30 in the cover 50 and ensuring soundproofing by the capsule structure.

Therefore, in the present embodiment, as shown in FIG. 1, a cooling mechanism 70 capable of air-cooling the device inside the cover 50 by opening and closing the opening of the cover 50 having a capsule structure is provided. There is.

The cooling mechanism 70 includes an opening (for example, openings 72 and 73, an opening of the grill shutter 60) that communicates the space outside the vehicle 1 with the space inside the cover 50, and an opening / closing device (for example, an opening / closing device) that opens and closes the opening. The valves 76 and 79, the grill shutter 60), and the outside air flow path 71 that guides the outside air flowing in from the opening to the periphery of the GPF 30 are provided.

The outside air flow path 71 is a flow path for allowing the outside air (that is, the outside air) of the vehicle 1 to flow along the power unit arranged in the internal space of the cover 50. The outside air flow path 71 is arranged so as to extend in the front-rear direction of the vehicle 1, and guides the outside air introduced into the vehicle 1 from the front of the vehicle toward the rear of the vehicle. As shown in FIG. 1, the outside air flow path 71 according to the present embodiment is arranged in the gap between the engine 10, the GPF 30 and the undercover 54, and the gap between the floor panel 56 and the undercover 54. The outside air flow path 71 can guide the outside air to the periphery of the GPF 30.

The outside air flowing in the outside air flow path 71 functions as a refrigerant for air-cooling the device to be cooled in the cover 50. The air that has been heated by heat exchange during air cooling flows in the outside air flow path 71 toward the rear of the vehicle and is discharged from the rear end opening of the outside air flow path 71. The outside air may be circulated in the outside air flow path 71 by using the traveling wind that flows into the vehicle 1 from the front of the vehicle as the vehicle 1 travels. Alternatively, the outside air may be circulated in the outside air flow path 71 by using the air flow forcibly generated by a fan or the like.

First, the grill shutter 60 will be described as a means for introducing the outside air into the outside air flow path 71. The grill shutter 60 is arranged at the front (front portion) of the vehicle 1 and takes in or shuts off the outside air (running wind) into the vehicle 1 through an opening formed in the front. The grill shutter 60 includes a plurality of rotating shafts 61 and a plurality of louvers 62 arranged in parallel with each other at predetermined intervals, and a drive unit (not shown) such as an actuator that rotates the louvers 62 around the rotating shaft 61. .) And.

By rotating the plurality of louvers 62 of the grill shutter 60 in the opening direction, an opening is formed between the plurality of louvers 62. This opening functions as an opening (air supply port) for introducing the outside air into the outside air flow path 71 through the grill shutter 60. On the other hand, by rotating the plurality of louvers 62 in the closing direction, the opening is closed by the louvers 62. In this case, the outside air is not introduced into the outside air flow path 71 through the grill shutter 60.

Next, as another means for introducing the outside air into the outside air flow path 71, the openings 72 and 73 provided in the undercover 54 and the opening / closing mechanism thereof will be described. The openings 72 and 73 are openings formed in the undercover 54 and function as vents. The opening 72 (air supply port) is formed in the undercover 54 on the front side of the vehicle with respect to the GPF 30. The opening 72 functions as an inflow port for outside air from the outside to the inside of the vehicle 1. On the other hand, the opening 73 (exhaust port) is formed in the undercover 54 on the rear side of the vehicle with respect to the GPF 30. The opening 73 functions as an outlet for outside air from the inside to the outside of the vehicle 1.

Ducts 74 and 75 (air supply ducts) for smoothly flowing outside air into the vehicle are provided around the opening 72 (air supply port). The duct 74 is arranged below the undercover 54 so as to extend forward from the opening 72. An inflow port 74a is formed at the front end of the duct 74. On the other hand, the duct 75 is arranged so as to extend rearward from the opening 72 in the outside air flow path 71 on the upper side of the undercover 54. An outlet 75a is formed at the rear end of the duct 75.

Further, the inflow port 74a at the front end of the duct 74 is provided with a rotary valve 76 (air supply valve) that opens and closes the inflow port 74a. The valve 76 is rotatably provided around a rotation shaft 76a. By rotating the valve 76 around the rotation shaft 76a by a drive unit (not shown) such as an actuator, the valve 76 opens and closes the inflow port 74a of the duct 74. The valve 76 functions as an opening / closing device that indirectly opens / closes the opening 72 (air supply port) of the undercover 54 by opening / closing the inflow port 74a of the duct 74.

When the inflow port 74a is opened by the valve 76, the outside air (running wind) flows into the duct 74 from the inflow port 74a and is guided to the outside air flow path 71 through the opening 72 and the duct 75. On the other hand, when the inflow port 74a is closed by the valve 76, the outside air (running wind) does not flow into the duct 74.

On the other hand, ducts 77 and 78 (exhaust ducts) for smoothly flowing out the air flowing in the outside air flow path 71 to the outside of the vehicle are provided around the opening 73 (exhaust port). The duct 77 is arranged below the undercover 54 so as to extend rearward from the opening 73. An outlet 77a is formed at the rear end of the duct 77. On the other hand, the duct 78 is arranged so as to extend forward from the opening 73 in the outside air flow path 71 on the upper side of the undercover 54. An inflow port 78a is formed at the front end of the duct 78.

Further, the outlet 77a at the rear end of the duct 77 is provided with a rotary valve 79 (exhaust valve) that opens and closes the outlet 77a. The valve 79 is rotatably provided about the rotation shaft 79a. By rotating the valve 79 around the rotation shaft 79a by a drive unit (not shown) such as an actuator, the outlet 77a of the duct 77 is opened and closed by the valve 79. The valve 79 functions as an opening / closing device that indirectly opens / closes the opening 73 (exhaust port) of the undercover 54 by opening / closing the outlet 77a of the duct 77.

When the outflow port 77a is opened by the valve 79, the air flowing in the outside air flow path 71 flows into the duct 78 from the inflow port 78a and flows out of the vehicle through the opening 73 and the duct 77. On the other hand, when the outflow port 77a is closed by the valve 79, the air in the outside air flow path 71 does not flow into the duct 78 and does not flow out of the vehicle.

In this embodiment, rotary valves 76 and 79 are used as the switchgear, but if the openings 72 and 73 can be opened and closed, various switchgear such as a slide valve, flap and shutter can be used. You may use it. Further, the openings 72 and 73 of the undercover 54 may be directly opened and closed by the opening / closing device without providing the ducts 74, 75, 77 and 78.

The configuration of the cooling mechanism 70 according to the present embodiment has been described above. Next, the operation of air-cooling the surrounding space of the GPF 30 by the cooling mechanism 70 will be described.

The cooling mechanism 70 according to the present embodiment air-cools the surrounding space of the power unit including the GPF 30 by introducing the outside air into the cover 50 from the opening and guiding the outside air to the periphery of the GPF 30 through the outside air flow path 71. The control unit 80 controls the cooling operation by the cooling mechanism 70. There are two paths for introducing the outside air into the outside air flow path 71: a path through the opening 72 (air supply port) of the undercover 54 and a path through the grill shutter 60. Both of these two routes may be used together, or only one of these routes may be used.

First, a cooling operation using a path through the opening 72 (air supply port) of the undercover 54 will be described.

When the GPF 30 in the cover 50 becomes hot during the traveling of the vehicle 1 and it is necessary to air-cool the space around the GPF 30, the control unit 80 opens the valves 76 and 79 and opens the undercover 54 72. , 73 is released. As a result, the traveling wind is taken into the vehicle, and the outside air is introduced into the outside air flow path 71 through the duct 74, the opening 72 (air supply port), and the duct 75, and is guided to the surrounding space of the GPF 30. As a result, the periphery of the GPF 30 is cooled by heat exchange between the low temperature outside air and the high temperature air around the GPF 30. The air after heat exchange is discharged to the outside of the vehicle through the duct 78, the opening 73 (exhaust port), and the duct 77.

In this way, a large amount of outside air is smoothly flowed around the GPF 30 through the opening 72 (air supply port), the outside air flow path 71, and the opening 73 (exhaust port). As a result, the GPF 30 in a high temperature state and its peripheral parts can be effectively cooled, and heat damage due to radiant heat of the GPF 30 can be suppressed.

On the other hand, when it is not necessary to air-cool the surrounding space of the GPF 30, the control unit 80 closes the valves 76 and 79 and closes the openings 72 and 73 of the undercover 54. In this case, the traveling wind is not taken into the vehicle, and the outside air does not flow into the outside air flow path 71 through the opening 72 (air supply port) of the undercover 54. As a result, the relatively low temperature GPF30 and its peripheral parts can be kept warm without being cooled. Further, since the openings 72 and 73 are closed, the sound inside the cover 50 does not leak to the outside of the vehicle through the openings 72 and 73, so that the soundproofing effect of the capsule structure is high.

Next, the cooling operation using the path through the grill shutter 60 will be described.

When it is necessary to air-cool the surrounding space of the GPF 30 in a high temperature state while the vehicle 1 is traveling, the control unit 80 opens the louver 62 of the grill shutter 60 to open the opening of the grill shutter 60. As a result, the traveling wind from the front to the rear of the vehicle is taken into the vehicle from the grill shutter 60 at the front of the vehicle 1, the outside air is introduced into the outside air flow path 71, and is guided to the surrounding space of the GPF 30. As a result, the peripheral space of the GPF 30 is cooled by the same heat exchange as described above. The air after heat exchange flows through the outside air flow path 71 toward the rear of the vehicle, and is discharged to the outside of the vehicle through an opening at the rear end of the outside air flow path 71 (for example, a gap formed at the rear of the undercover 54). ..

By allowing the outside air to flow around the GPF 30 through the grill shutter 60 in this way, the GPF 30 in a high temperature state and its peripheral parts can be effectively cooled and heat damage can be suppressed. Even when the outside air is taken in from the grill shutter 60, even if the opening 73 (exhaust port) of the undercover 54 is opened by the valve 79 and the air in the outside air flow path 71 is discharged to the outside of the vehicle through the opening 73. Good.

On the other hand, when it is not necessary to air-cool the surrounding space of the GPF 30, the control unit 80 closes the louver 62 of the grill shutter 60 and closes the opening of the grill shutter 60. In this case, the traveling wind is not taken into the vehicle from the grill shutter 60, and the outside air does not flow into the outside air flow path 71. As a result, the GPF 30 and its peripheral parts can be kept warm without being cooled, and the soundproofing effect of the capsule structure is also high.

[3. Control of cooling operation according to switching of operation mode of filter device]
Next, a method of controlling the cooling operation of the cooling mechanism 70 based on the operation mode of the GPF 30 by the control unit 80 according to the present embodiment will be described.

As described above, the vehicle 1 according to the present embodiment has a capsule structure, and the power units such as the engine 10, the transmission 20, and the GPF 30 are covered with the cover 50 (see FIG. 1). Therefore, the periphery of the exhaust system such as the GPF 30 is also covered with the cover 50, and the peripheral space of the exhaust system is almost a closed space, so that heat tends to be trapped. Moreover, when the GPF 30 is performing the filter regeneration process, the GPF 30 becomes high temperature (for example, 600 ° C. or higher) due to the heat of combustion. The operation mode in which this reproduction process is performed is referred to as a reproduction mode. In the reproduction mode, radiant heat from the high temperature GPF 30 tends to cause heat damage to the peripheral parts of the GPF 30, so it is desirable to cool the periphery of the GPF 30 by the cooling mechanism 70.

On the other hand, the GPF 30 performs a normal exhaust gas purification process during normal operation without performing the regeneration process. The operation mode in which this normal exhaust gas purification process is performed is referred to as a normal mode. In the normal mode, the GPF 30 operates at a lower temperature than in the reproduction mode. Therefore, heat damage is unlikely to occur in the peripheral device of the GPF 30, so that the peripheral device of the GPF 30 does not necessarily have to be cooled by the cooling mechanism 70. Therefore, when cooling is not required, the openings of the cooling mechanism 70 (for example, the openings 72 and 73 of the undercover 54 and the openings of the grill shutter 60 shown in FIG. 1) are closed to improve the soundproofing of the capsule structure. It is preferable to secure it.

Here, as a method of controlling the cooling operation by the cooling mechanism 70, as described in Patent Documents 2 and 3, a method of controlling the start of the cooling operation by using an actually measured temperature such as the catalyst temperature of the exhaust system or the ambient temperature as a trigger. Can be considered. However, if the control method is triggered by the measured temperature, the cooling operation is started after the ambient temperature of the GPF 30 actually rises, so that the cooling operation of the surrounding space cannot keep up with the temperature rise of the GPF 30. In addition, it will be delayed. If the start timing of the cooling operation is delayed in this way, the ambient temperature of the GPF 30 rises above the permissible temperature, and the peripheral parts of the filter device may be damaged by heat.

Therefore, in the present embodiment, in order to solve the problem of such a delay, whether the control unit 80 executes the cooling operation by the cooling mechanism 70 based on whether the operation mode of the GPF 30 is the reproduction mode or the normal mode. Control whether or not. Specifically, when the operation mode of the GPF 30 is the reproduction mode, the control unit 80 causes the cooling mechanism 70 to execute the cooling operation. On the other hand, when the operation mode of the GPF 30 is the normal mode, the control unit 80 stops the cooling operation by the cooling mechanism 70.

Further, according to the present embodiment, the control unit 80 is characterized in that the control unit 80 controls the start and end of the cooling operation by the cooling mechanism 70 based on the switching timing of the operation mode of the GPF 30. For example, the control unit 80 starts the cooling operation by the cooling mechanism 70 according to the timing of switching the operation mode of the GPF 30 from the normal mode to the reproduction mode (that is, the start timing of the reproduction mode). Further, the control unit 80 ends the cooling operation by the cooling mechanism 70 according to the timing of switching the operation mode of the GPF 30 from the reproduction mode to the normal mode (that is, the end timing of the reproduction mode).

Here, with reference to FIG. 2, a specific example of the switching timing of the operation mode of the GPF 30 and the control timing of the cooling operation will be described in detail. FIG. 2 is a timing chart showing the switching timing of the operation mode of the GPF 30 according to the present embodiment and the opening / closing timing of the opening by the cooling mechanism 70.

The GPF front-rear differential pressure P shown in FIG. 2 is the pressure difference between the exhaust gas introduced into the GPF 30 and the exhaust gas discharged from the GPF 30. This differential pressure P corresponds to the pressure loss of the exhaust gas in the GPF 30, and represents the degree to which the filter is clogged by the particulate matter in the GPF 30. The higher the degree of clogging, the larger the differential pressure P (pressure loss). The reproduction flag signal shown in FIG. 2 is a mode control signal for switching the operation mode of the GPF 30. If the reproduction flag signal is HIGH, the reproduction mode is executed, and if the reproduction flag signal is LOW, the normal mode is executed.

The control unit 80 switches the operation mode of the GPF 30 based on the differential pressure P. For example, the control unit 80 switches the operation mode of the GPF 30 from the normal mode to the reproduction mode (t ₁ , t ₆ ) _{, triggered by the differential pressure P rising to a predetermined upper limit value P 1 during the normal mode.} In response to the switching to the reproduction mode, the control unit 80 outputs the reproduction flag signal (HIGH) to the GPF 30. As a result, in the GPF 30, the filter regeneration process is started.

On the other hand, the control unit 80 as a trigger that the differential pressure P has decreased to a predetermined lower limit value P ₂ during playback mode, switches to the normal mode the operating mode of GPF30 from the playback mode (t _5). In response to the switching to the normal mode, the control unit 80 outputs a reproduction flag signal (LOW) to the GPF 30. As a result, in the GPF 30, the filter regeneration process is completed, and the normal exhaust gas purification process is resumed.

In this way, by switching the operation mode of the GPF 30 based on the differential pressure P, the reproduction process of the GPF 30 can be started and ended at an appropriate timing according to the degree of clogging of the filter of the GPF 30. Therefore, the exhaust gas purification process by GPF30 can be stably continued.

Next, the relationship between the operation mode switching control of the GPF 30 according to the present embodiment and the on / off control of the cooling operation by the cooling mechanism 70 will be described.

The opening / closing signal of the opening shown in FIG. 2 is a signal for controlling the opening / closing of the above-mentioned opening (for example, the openings 72 and 73 of the undercover 54 and the opening of the grill shutter 60 shown in FIG. 1). This open / close signal represents on / off of the cooling operation by the cooling mechanism 70. If the open / close signal is HIGH, the opening is opened and the cooling operation by the cooling mechanism 70 is executed. If the open / close signal is LOW, the opening is closed and the cooling operation by the cooling mechanism 70 is stopped.

Here, as shown in FIG. 2, the reproduction flag signal and the open / close signal are synchronized without delay. This means that the operation mode switching control of the GPF 30 and the on / off control of the cooling operation by the cooling mechanism 70 are synchronized. When the operation mode of the GPF 30 is switched to the reproduction mode, the control unit 80 opens the opening and starts the cooling operation by the cooling mechanism 70 (t ₁ , t ₆ ). Further, when the operation mode of the GPF 30 is switched to the normal mode, the control unit 80 closes the opening and stops the cooling operation by the cooling mechanism 70 (t ₅ ).

As described above, in the present embodiment, the operation mode switching control of the GPF 30 and the on / off control of the cooling operation by the cooling mechanism 70 are synchronized. That is, the switching of the operation mode of the GPF 30 is used as a trigger to start / end the cooling operation by the cooling mechanism 70. This solves the problem of delay in the start timing of the cooling operation, which occurs in the method of controlling the cooling operation by using the measured temperature such as the catalyst temperature as a trigger as described in Patent Documents 2 and 3.

That is, in the present embodiment, the cooling operation by the cooling mechanism 70 is started immediately when the GPF 30 is switched from the normal mode to the reproduction mode. As a result, the peripheral space of the GPF 30 can be started to be cooled at the same time as the start of the reproduction mode, and the increase in the ambient temperature T of the GPF 30 can be suppressed at an early stage. Therefore, even during the regeneration mode, the ambient temperature T can be maintained at a _{predetermined allowable temperature T max or less that can suppress heat damage.}

Here, with reference to FIG. 2, a specific example of the change in the ambient temperature T of the GPF 30 when the cooling operation is controlled by using the switching of the operation mode of the GPF 30 as a trigger in the present embodiment will be described. The solid line in FIG. 2 shows the temperature change when the reproduction flag signal according to the present embodiment is controlled as a trigger, and the broken line shows the temperature when the temperature according to the prior art (for example, Patent Documents 2 and 3) is controlled as a trigger. It shows the temperature change of.

As shown in FIG. 2, in the normal state in which the operation mode of the GPF 30 is the normal mode and the cooling operation by the cooling mechanism 70 is not performed ( _{~ t 1} ), the ambient temperature T of the GPF 30 is a substantially constant temperature T ₁ . Yes, it is low and stable. During the normal mode, when the differential pressure P is increased to a predetermined upper limit value P _1, the operation mode of GPF30 is switched from the normal mode to the playback mode (t _1). After this switching (t ₁ ), the ambient temperature T of the GPF 30 gradually rises from _{T 1 as the temperature of the GPF 30 to be regenerated is raised.}

Here, according to the control according to the prior art, the cooling operation is started by using the measured temperature (catalyst temperature, ambient temperature, etc.) of the exhaust system as a trigger. Therefore, after a predetermined time has elapsed from the time of switching to the reproduction mode (t ₁ ), the cooling operation is finally started when the actual ambient temperature T rises to a _{predetermined threshold value T 2 (t 2).} As a result, the cooling operation for lowering the ambient temperature T is delayed. Therefore, as shown by the broken line in FIG. 2 _{, the ambient temperature T rises significantly during the reproduction mode (t 1 to t 5} ), and the maximum temperature reached T ₄ exceeds the allowable temperature T _{max (t 4).} ). Therefore, according to the control according to the prior art, heat damage may occur to the peripheral device.

On the other hand, according to the control according to the present embodiment, the cooling operation is started by using the control signal (for example, the reproduction flag signal) of the operation mode of the GPF 30 as a trigger. As a result, at the same time as switching to the reproduction mode, the opening of the cooling mechanism 70 is opened and the cooling operation is immediately started (t ₁ ). As a result, the increase in the ambient temperature T of the GPF 30 is suppressed at an early stage. Therefore, as shown by the solid line in FIG. 2, in the present embodiment, even if the ambient temperature T of the GPF 30 rises _{during the reproduction mode (t 1 to t 5 ), the maximum reached temperature T 3} is a predetermined allowable temperature T. It does not exceed _{max (t 3} ). Therefore, according to the present embodiment, it is possible to suppress heat damage to the peripheral device of the GPF 30.

Next, during the reproduction mode (t _{1 to t 5} ), when the reproduction process of the filter of the GPF 30 proceeds and the differential pressure P _{drops to a predetermined lower limit value P 2} , the operation mode of the GPF 30 is usually changed from the reproduction mode. The mode can be switched (t ₅ ). Further, in accordance with the switching to the normal mode, the opening of the cooling mechanism 70 is closed, and the cooling operation is immediately terminated (t ₅ ). During the subsequent normal mode (t _{5 to t 6} ), the low temperature GPF 30 performs the normal exhaust gas purification treatment while the cooling operation by the cooling mechanism 70 is stopped, so that the ambient temperature of the GPF 30 is stopped. T is maintained at a substantially constant temperature T _1.

As described above, according to the control of the cooling operation according to the present embodiment, the switching timing of the operation mode of the GPF 30 and the start / end timing of the cooling operation by the cooling mechanism 70 are synchronized. As a result, the cooling mechanism 70 performs the cooling operation only during the period when the GPF 30 undergoes the regeneration process and becomes high in temperature. Therefore, the peripheral space of the GPF 30 can be efficiently cooled at the timing when cooling is required, and the heat damage of the peripheral device can be suppressed.

[4. Control of the second embodiment]
Next, the control of the cooling operation according to the second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a timing chart showing the switching timing of the operation mode of the GPF 30 and the opening / closing timing of the opening by the cooling mechanism 70 according to the second embodiment.

In the control example (FIG. 2) according to the first embodiment described above, the cooling operation by the cooling mechanism 70 is terminated by triggering the switching from the reproduction mode to the normal mode. However, the present invention is not limited to such examples. For example, the cooling operation by the cooling mechanism 70 may be terminated based on the temperature associated with the operation of the filter device (eg, GPF 30).

Here, the temperature related to the operation of the GPF 30 is a temperature that fluctuates with the operation of the GPF 30, for example, the ambient temperature T of the GPF 30, the temperature of the exhaust gas discharged from the GPF 30, or the catalyst inside the GPF 30. It may be various temperatures such as temperature. In the second embodiment described below, an example in which the cooling operation by the cooling mechanism 70 is terminated by using the ambient temperature T of the GPF 30 as a trigger will be described.

As shown in FIG. 3, in the second embodiment, similarly to the first embodiment, the opening of the cooling mechanism 70 is matched with _{the switching timing (t 1} , t _{6) from the normal mode to the reproduction mode.} Is released and the cooling operation is started. On the other hand, in the second embodiment, unlike the first embodiment, the ambient temperature T is predetermined in accordance with _{the switching timing (t 5) from the reproduction mode to the normal mode without ending the cooling operation.} At the timing (t ₇ ) when the temperature drops to the threshold value (for example, temperature T ₁ ), the opening of the cooling mechanism 70 is closed to end the cooling operation.

As described above, in the second embodiment, the cooling operation by the cooling mechanism 70 is terminated by triggering the decrease in the ambient temperature T or the like of the GPF 30. As a result, the cooling operation can be terminated after the ambient temperature T of the GPF 30 is sufficiently lowered, so that heat damage to the peripheral device can be suppressed more reliably.

In the example of FIG. 3, the end timing (t ₇ ) of the _{cooling operation is delayed with respect to the end timing (t 5) of the reproduction mode.} This means that the cooling operation is continued _{for a while (t 5 to t 7} ) even after the end of the reproduction mode. Even if the cooling operation is continued after the end of the reproduction mode in this way, there is no adverse effect on the peripheral parts of the GPF 30. On the other hand, if the start timing _{of the cooling operation is delayed with respect to the start timing of the reproduction mode (t 1} , t ₆ ), the problem of heat damage of the peripheral device described above occurs, which is not preferable. Therefore, also in the second embodiment, the start timing of the reproduction mode (t ₁ , t ₆ ) and the start timing of the cooling operation, that is, the opening timing of the opening (t ₁ , t ₆ ) are synchronized.

[5. Summary]
The vehicle 1 according to the present embodiment has been described in detail above. According to this embodiment, the cooling operation by the cooling mechanism 70 is controlled based on the switching timing of the operation mode of the filter device (for example, GPF30). In particular, the opening of the cooling mechanism 70 is opened and the outside air is introduced around the GPF 30 to start the cooling operation according to the timing of switching the operation mode of the GPF 30 from the other mode to the reproduction mode.

As a result, the periphery of the GPF 30 can be started to be cooled without delay in accordance with the start timing of the regeneration process by the GPF 30. Therefore, since the periphery of the GPF 30 can be appropriately cooled at an early stage in the reproduction mode, even if the GPF 30 becomes high in the regeneration mode, the ambient temperature T of the GPF 30 can be stabilized at a low level below the _{allowable temperature T max.} Therefore, when the operation mode of the GPF 30 is switched, the delay of the cooling start timing can be suppressed, and the heat damage of the peripheral parts due to the radiant heat from the GPF 30 can be suppressed.

Further, according to the present embodiment, a cooling mechanism 70 suitable for a capsule structure in which the power unit is covered with a cover 50 is installed. In the cooling mechanism 70, for example, the undercover 54 or the front grill of the vehicle 1 has openings (for example, openings 72 and 73, openings of the grill shutter 60) and an opening / closing device (for example) for taking in outside air (running wind). , Valves 76, 79, grill shutter 60) are provided. Further, an outside air flow path 71 is provided to guide the outside air flowing in from the opening to the periphery of the GPF 30. With such a structure, the opening can be opened to air-cool the periphery of the GPF 30 only when air cooling is required, and when air cooling is not required, the opening can be closed to maintain the airtightness of the capsule structure. Therefore, it is possible to achieve both the soundproofing effect of the capsule structure and the heat damage countermeasure of GPF30.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such embodiments. It is clear that a person skilled in the art can come up with various modifications or modifications within the scope of the claims, and it is understood that these also naturally belong to the technical scope of the present invention. Will be done.

In the above embodiment, an example in which one outside air flow path 71 is provided on the bottom surface side of the engine 10, the transmission 20, the GPF 30, and the like in the cover 50 has been described, but the present invention is not limited to such an example. For example, the outside air flow path 71 may be provided on the left side surface, the right side surface, or the upper surface side of the engine 10 or the like. Further, a plurality of outside air flow paths 71 may be provided around the engine 10 or the like.

Further, in the above embodiment, the upper side of the engine 10 or the like is covered by the upper cover 52, and the lower side of the engine 10 or the like is covered by the structural member (undercover 54) of the vehicle 1. Not limited. For example, the lower side of the engine 10 may be covered with a lower cover which is a member different from the structural member of the vehicle 1. In that case, the upper cover 52 and the lower cover may form a capsule structure in which the periphery of the engine 10 or the like is covered.

Further, in the above embodiment, an example of GPF 30 is given as a filter device for capturing particulate matter contained in the exhaust gas discharged from the engine 10, but the present invention is not limited to such an example. In the case of a vehicle fueled by light oil, the filter device may be, for example, a DPF (Diesel Particulate Filter).

In the above embodiment, the control unit 80 detects the degree of clogging of the GPF 30 based on the differential pressure P of the exhaust gas before and after the GPF 30, and regenerates the GPF 30 irregularly only when the clogging occurs. Was running. However, the present invention is not limited to such examples. For example, the control unit 80 may cause the GPF 30 to execute the regeneration process periodically for each predetermined mileage. Further, the processing time of the regeneration processing may be constant, or may be varied depending on the degree of clogging of the filter and the like.

Further, in the above embodiment, the timing of switching to the reproduction mode in the GPF 30 and the timing of starting the cooling operation of the cooling mechanism 70 are synchronized, but the present invention is not limited to this example. For example, the start timing of the cooling operation may be slightly delayed or advanced with respect to the switching timing to the reproduction mode.

The present invention is applicable to vehicles equipped with a filter device such as a GPF or DPF.

1 Vehicle 2 Vehicle room 3 Engine room 10 Engine 20 Transmission 30 GPF (filter device)
32 Exhaust path 50 Cover 52 Top cover 54 Undercover 56 Floor panel 60 Grill shutter 61 Rotating shaft 62 Louver 70 Cooling mechanism 71 Outside air flow path 72, 73 Opening 74, 75, 77, 78 Duct 76, 79 Valve 80 Control unit

Claims (8)

With the engine
A filter device that captures particulate matter contained in the exhaust gas discharged from the engine, and
A cover that covers the engine and the filter device,
A cooling mechanism that cools the filter device by sending outside air to the periphery of the filter device.
A control unit that controls the cooling mechanism and
With
The control unit controls the cooling operation by the cooling mechanism based on the switching timing of the operation mode of the filter device. The operating mode of the filter device includes a regeneration mode for burning and removing particulate matter accumulated inside the filter device.
The vehicle according to claim 1, wherein the control unit starts a cooling operation by the cooling mechanism according to a timing of switching the operation mode of the filter device to the reproduction mode. The vehicle according to claim 2, wherein the control unit terminates the cooling operation by the cooling mechanism according to the timing at which the reproduction mode is terminated. The vehicle according to claim 2, wherein the control unit terminates the cooling operation by the cooling mechanism based on the temperature related to the operation of the filter device. The control unit switches the operation mode of the filter device based on the pressure difference between the exhaust gas introduced into the filter device and the exhaust gas discharged from the filter device, according to claims 1 to 4. The vehicle according to any one item. The cooling mechanism
An opening that communicates the outside air with the internal space of the cover,
A switchgear that opens and closes the opening,
An outside air flow path that guides the outside air flowing in from the opening to the periphery of the filter device,
With
The vehicle according to any one of claims 1 to 5, wherein the control unit opens and closes the opening by the switchgear based on the switching timing of the operation mode of the filter device. The opening is an opening formed in the undercover of the vehicle.
The vehicle according to claim 6, wherein the switchgear is a valve that opens and closes the opening. The opening / closing device is a grill shutter provided on the front of the vehicle.
The vehicle according to claim 6, wherein the opening is an opening provided in the grill shutter.

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