JP2017044124A - Electrothermal warming-up device and vehicle driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrothermal warming-up device which enables improvement of the efficiency of heat transmission from an exhaust gas to a lubrication oil.SOLUTION: An electrothermal warming-up device includes: a thermoelectric transducer 80 which forms a temperature difference between a first surface 83 and a second surface 84 through energization; a warmer 60 which has a coolant pipe 61 for circulating a coolant W and a lubrication oil pipe 62 for circulating a lubrication oil O and may heat the lubrication oil O with heat of the heated coolant W; and an exhaust heat exchanger 70 which transmits heat of an exhaust gas G to enable heat exchange. The first surface 83 of the thermoelectric transducer 80 and the warmer 60 are provided contacting with each other so as to conduct heat therebetween, and the second surface 84 of the thermoelectric transducer 80 and the exhaust heat exchanger 70 are provided and brought into contact with each other so as to conduct heat therebetween.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a thermoelectric warming device and a vehicle drive device mounted on a vehicle, for example.

  2. Description of the Related Art Conventionally, there is known a thermoelectric power generation apparatus in which a thermoelectric conversion element is provided on the outer surface of an exhaust pipe of an internal combustion engine and power is generated using heat of exhaust gas. In such a thermoelectric power generation apparatus, in order to ensure a temperature difference in the thermoelectric conversion element, high temperature exhaust gas and low temperature cooling water may be used. For this reason, a thermoelectric power generation apparatus has been developed in which an exhaust pipe and a cooling water pipe are disposed close to each other and a thermoelectric conversion element is sandwiched between the exhaust pipe and the cooling water pipe (see Patent Document 1). . In this thermoelectric generator, since the cooling water is used on the low temperature side, the cooling water is heated by the heat of the exhaust gas, and the warm-up can be accelerated during the warm-up operation. Further, when the cooling water is heated, the lubricating oil of the transmission mechanism through which the cooling water is circulated is also heated, so that the warm-up of the transmission mechanism is accelerated.

Special table 2011-521139 gazette

  However, in warm-up using the above-described thermoelectric generator, the heat of the exhaust gas is transferred to the lubricating oil of the transmission mechanism through the thermoelectric conversion element and the cooling water, so that the thermoelectric power is discharged between the exhaust gas and the lubricating oil. Since the conversion element and the cooling water are interposed, the heat transfer efficiency is poor, and it has been desired to improve the warm-up efficiency.

  Then, it aims at providing the thermoelectric warming-up apparatus which can improve the heat transfer efficiency from exhaust gas to lubricating oil.

  A thermoelectric warm-up device according to the present disclosure includes a thermoelectric conversion element that forms a temperature difference between a first surface and a second surface by energization, a cooling water pipe that circulates cooling water, and a lubricating oil pipe that circulates lubricating oil. And a first heat exchanger capable of heating the lubricating oil by the heat of the heated cooling water, and a second heat exchanger capable of transferring heat by transferring heat of exhaust gas. And the first surface of the thermoelectric conversion element and the first heat exchanger are provided in contact with each other so as to be capable of conducting heat, and the second surface of the thermoelectric conversion element and the second heat exchange are provided. It is provided in contact with the vessel so as to allow heat conduction.

  According to this thermoelectric warming device, since the first heat exchanger having the cooling water pipe and the lubricating oil pipe is provided in contact with the thermoelectric conversion element, the heat of the exhaust gas is passed from the exhaust pipe through the thermoelectric conversion element. To the lubricating oil pipe of the first heat exchanger. Thereby, the heat transfer efficiency from the exhaust gas to the lubricating oil can be improved as compared with the case where the heat of the exhaust gas is conducted from the exhaust pipe to the lubricating oil through the thermoelectric conversion element and further through the cooling water.

The block diagram which shows the vehicle of this Embodiment. The schematic diagram which shows the thermoelectric warming-up apparatus of this Embodiment.

  Hereinafter, the present embodiment will be described with reference to FIGS. 1 and 2. First, an example of the vehicle 1 according to the present embodiment will be described with reference to FIG.

  As shown in FIG. 1, a vehicle 1 according to the present embodiment includes an internal combustion engine (E / G) 2, an unillustrated intake device, an exhaust device 3, a cooling device 4, and a vehicle drive device 5. The battery 6 and the ECU 7 are provided. The internal combustion engine 2 is an internal combustion engine such as a gasoline engine or a diesel engine. The internal combustion engine 2 has a cylinder block and a cylinder head, and a water jacket through which cooling water W, which will be described later, can flow is formed in the cylinder block and the cylinder head.

  The intake device has an intake pipe and an intake manifold (not shown), and supplies combustion air to each cylinder of the internal combustion engine 2.

  The exhaust device 3 has an exhaust manifold 30 and an exhaust pipe 31. The exhaust manifold 30 circulates the exhaust gas G discharged from each cylinder of the internal combustion engine 2. The exhaust pipe 31 is provided from the exhaust manifold 30 to the exhaust port. A catalyst 32 is provided in the exhaust pipe 31. The catalyst 32 is composed of, for example, a three-way catalyst, and has a purification function of changing carbon monoxide, hydrocarbons, and nitrogen oxides into harmless components by a chemical reaction.

  The cooling device 4 includes a water pump 40, a water jacket 2a, a radiator 41, a thermostat 42, and a cooling pipe 43 that connects them.

  The discharge port of the water pump 40 is connected to the water jacket 2a, and the cooling water W cools the internal combustion engine 2 by circulating the cooling water W from the water pump 40 to the water jacket 2a. The radiator 41 is connected to the downstream side of the water jacket 2a, and cools the cooling water W by exchanging heat between the cooling water W and external air. The thermostat 42 is connected to the downstream side of the radiator 41 and the upstream side of the water pump 40, and is opened or closed depending on the temperature of the cooling water W.

  The vehicle drive device 5 includes an automatic transmission (A / T) 50 and a thermoelectric warming device 51. The automatic transmission 50 is connected to the internal combustion engine 2. The automatic transmission 50 includes a torque converter, an automatic transmission mechanism (transmission mechanism) 50a (see FIG. 2), a hydraulic control device (valve body), and the like, and changes the output from the internal combustion engine 2 based on a command from the ECU 7. Output is possible. That is, in the automatic transmission mechanism 50a, the lubricating oil O is stored under the automatic transmission mechanism 50a driven by the internal combustion engine 2, and lubricates and cools the movable part of the automatic transmission mechanism 50a.

  The thermoelectric warm-up device 51 has a warmer (first heat exchanger) 60, an exhaust heat exchanger (second heat exchanger) 70, and a thermoelectric conversion element (thermoelectric conversion element) 80. It is mounted on the automatic transmission 50.

  As shown in FIG. 2, the warmer 60 includes a cooling water pipe 61 that circulates the cooling water W and a lubricating oil pipe 62 that circulates the lubricating oil O, and heat exchange is possible between the cooling water W and the lubricating oil O. . In particular, the warmer 60 can heat the lubricating oil O by the heat of the heated cooling water W. The cooling water pipe 61 and the lubricating oil pipe 62 are in contact with the outer walls in a wide area inside the warmer 60, or the cooling water W flow path and the lubricating oil O oil path are adjacent to each other with a partition wall therebetween. It is configured. Thereby, heat exchange with the cooling water W and the lubricating oil O is efficiently realizable.

  In the present embodiment, the cooling water pipe 61 connects the cooling pipe 43 between the water jacket 2 a and the radiator 41 and the thermostat 42. A cooling water pipe opening / closing valve 63 capable of opening / closing the cooling water pipe 61 is interposed upstream of the cooling water pipe 61. Lubricating oil pipe 62 distributes lubricating oil O stored in automatic transmission mechanism 50a by a pump (not shown). A lubricating oil pipe opening / closing valve (opening / closing valve) 64 capable of opening and closing the lubricating oil pipe 62 is interposed upstream of the lubricating oil pipe 62. In the present embodiment, the lubricating oil pipe opening / closing valve 64 is provided in the hydraulic control device.

  The exhaust heat exchanger 70 has a substantially cylindrical shape, is interposed in a part of the exhaust pipe 31, and the exhaust gas G circulates inside. In FIG. 1, the exhaust pipe 31 and the exhaust heat exchanger 70 are described separately, but actually, the exhaust heat exchanger 70 is interposed in a part of the exhaust pipe 31. Also, the alternate long and short dash line in FIG. 1 indicates the heat flow between the exhaust pipe 31 and the exhaust gas G and the exhaust heat exchanger 70.

  As shown in FIG. 2, the exhaust heat exchanger 70 includes a large number of fins 71 protruding inward from the inner peripheral surface, and a planar heat radiating surface 72 formed on a part of the outer peripheral surface corresponding to the fins 71. Have. By providing a large number of fins 71 on the inner peripheral side of the heat radiating surface 72, the heat of the exhaust gas G is efficiently transferred to the heat radiating surface 72. That is, the exhaust heat exchanger 70 transfers the heat of the exhaust gas G to enable heat exchange. In the present embodiment, the exhaust heat exchanger 70 is interposed in the exhaust pipe 31, but the present invention is not limited to this. For example, a branch pipe is provided from the exhaust pipe 31, and the exhaust heat exchanger is provided in the branch pipe. 70 may be provided.

  The thermoelectric conversion element 80 is configured by arranging a large number of Peltier elements each composed of a pair of a P-type thermoelectric semiconductor 81 and an N-type thermoelectric semiconductor 82 in a planar shape. The thermoelectric conversion element 80 has a first surface 83 and a second surface 84, and forms a temperature difference between the first surface 83 and the second surface 84 by energization. The low temperature side and the high temperature side of the temperature difference can be reversed depending on the polarity of the applied voltage. Further, the thermoelectric conversion element 80 can generate electric power by generating a Seebeck effect corresponding to a temperature difference between the first surface 83 and the second surface 84.

  The first surface 83 of the thermoelectric conversion element 80 and the warmer 60 are provided in contact with each other so as to be able to conduct heat. In the present embodiment, the ceramic substrate 85 is interposed between the first surface 83 and the warmer 60, and the first surface 83 and the warmer 60 are in indirect contact with each other. That is, the first surface 83 and the warmer 60 may be in direct contact or indirect contact, and in either case, the first surface 83 and the warmer 60 are provided so as to be able to conduct heat. Similarly, the 2nd surface 84 of the thermoelectric conversion element 80 and the exhaust heat exchanger 70 are provided in contact so that heat conduction is possible. A ceramic substrate 86 is interposed between the second surface 84 and the exhaust heat exchanger 70, and the second surface 84 and the exhaust heat exchanger 70 are in indirect contact with each other. That is, the second surface 84 and the exhaust heat exchanger 70 may be either in direct contact or indirect contact, and in either case, the second surface 84 and the exhaust heat exchanger 70 are provided so as to be able to conduct heat.

  The battery 6 is connected to the thermoelectric conversion element 80 via the controller 8. The controller 8 is controlled by the ECU 7. The battery 6 is switched to charge the thermoelectric conversion element 80 by applying a voltage to the thermoelectric conversion element 80 or to charge the electric power generated by the thermoelectric conversion element 80 by the controller 8 that has received a command from the ECU 7. In FIG. 1, the battery 6 is described as a dedicated battery for the thermoelectric conversion element 80. However, the battery 6 is not limited to this, and may be a battery 6 that supplies power to other power consuming units such as a motor. Good.

  The ECU 7 includes, for example, a CPU, a ROM that stores a processing program, a RAM that temporarily stores data, an input / output port, and a communication port, and various signals such as a control signal of a hydraulic control device. Is output from the output port. The ECU 7 can open and close the cooling water pipe opening / closing valve 63 and the lubricating oil pipe opening / closing valve 64 by electrical commands. Further, the ECU 7 controls the controller 8.

  Next, operation | movement of the thermoelectric warming-up apparatus 51 of this Embodiment is demonstrated below.

  As shown in FIG. 1, the exhaust gas G is discharged from the exhaust pipe 31 when the internal combustion engine 2 is started. As a result, as shown in FIG. 2, the exhaust gas G flows through the exhaust heat exchanger 70, and the heat of the exhaust gas G is conducted from the fins 71 to the heat radiation surface 72.

  Further, as shown in FIG. 1, when the cooling water W performs a warm-up operation at a low temperature immediately after the internal combustion engine 2 is started, the ECU 7 opens the cooling water pipe opening / closing valve 63 and the lubricating oil pipe opening / closing valve 64. Thereby, the cooling water W discharged from the water pump 40 flows through the water jacket 2a and cools the internal combustion engine 2. A part of the cooling water W flowing out from the internal combustion engine 2 is sucked by the water pump 40 through a bypass circuit (not shown). Here, when the cooling water W flowing through the thermostat 42 is lower than the predetermined temperature, the thermostat 42 remains closed, but when the cooling water W is higher than the predetermined temperature, the thermostat 42 changes to the open state.

  The other part of the cooling water W flowing out of the internal combustion engine 2 flows into the cooling water pipe 61 of the warmer 60 through the opened cooling water pipe opening / closing valve 63 (see FIG. 2), and heats the lubricating oil O so as to heat it. Exchanged. Then, the cooling water W is sucked by the water pump 40 through the thermostat 42.

  Further, the pump of the automatic transmission 50 discharges the lubricating oil O stored in the automatic transmission mechanism 50a and flows into the lubricating oil pipe 62 of the warmer 60 through the opened lubricating oil pipe opening / closing valve 64 (see FIG. 2). Heat exchange is performed so as to be heated by the cooling water W. Then, the lubricating oil O is returned to the automatic transmission mechanism 50a again.

  Here, heat from the heat radiation surface 72 of the exhaust heat exchanger 70 is conducted to the warmer 60 through the thermoelectric conversion element 80, and the high heat of the exhaust gas G is transferred to the cooling water W and the lubricating oil O that circulates inside the warmer 60. Communicated. For this reason, since the high heat of the exhaust gas G can be directly radiated to the cooling water W and the lubricating oil O, heat exchange can be performed efficiently, and heating of the cooling water W and the lubricating oil O can be promoted. .

  In the warm-up operation, the ECU 7 controls the controller 8 to energize the thermoelectric conversion element 80 from the battery 6 so that the first surface 83 is at a high temperature and the second surface 84 is at a low temperature. As a result, the exhaust heat exchanger 70 in contact with the low temperature side second surface 84 is cooled, so that the warmer 60 in contact with the high temperature side first surface 83 is heated more. In addition, the heating rate of the lubricating oil O can be increased. That is, during the warm-up operation, the amount of heat transferred from the exhaust heat exchanger 70 to the warmer 60 can be increased by energizing the thermoelectric conversion element 80 with the battery 6 connected to the thermoelectric conversion element 80.

  Here, the internal combustion engine 2 and the automatic transmission 50 differ in the amount of heat required for warming up and the warming up temperature. For this reason, it is preferable to separately control the amount of heat released from the exhaust heat exchanger 70 and the thermoelectric conversion element 80 to the cooling water W and the lubricating oil O. Therefore, the ECU 7 can appropriately control the cooling water pipe opening / closing valve 63 and the lubricating oil pipe opening / closing valve 64 to optimize the flow rates of the cooling water W and the lubricating oil O, respectively, thereby realizing an optimal warm-up.

  Next, when the cooling water W is sufficiently heated, the warm-up operation ends and the operation is switched to the normal operation. At this time, the controller 8 can cause the thermoelectric conversion element 80 to generate power using the temperature difference between the first surface 83 and the second surface 84 and charge the battery 6 in accordance with a command from the ECU 7. That is, in this thermoelectric warm-up device 51, after the warm-up operation, the battery 6 can be charged by generating electricity with the thermoelectric conversion element 80 due to the temperature difference between the warmer 60 and the exhaust heat exchanger 70. Further, at this time, it is possible to generate power with a temperature difference between the exhaust gas G and the cooling water W by controlling the lubricating oil pipe opening / closing valve 64 to suppress the flow rate of the lubricating oil O.

  As described above, according to the thermoelectric warm-up device 51 of the present embodiment, since the warmer 60 having the cooling water pipe 61 and the lubricating oil pipe 62 is provided in contact with the thermoelectric conversion element 80, the exhaust gas G Heat is conducted from the exhaust pipe 31 to the lubricating oil pipe 62 of the warmer 60 through the thermoelectric conversion element 80. As a result, the heat transfer efficiency from the exhaust gas G to the lubricating oil O is higher than when the heat of the exhaust gas G is conducted from the exhaust pipe 31 through the thermoelectric conversion element 80 and further through the cooling water W to the lubricating oil O. Can be improved.

  Further, according to the thermoelectric warming-up device 51 of the present embodiment, since the thermoelectric warming-up device 51 is mounted on the automatic transmission 50, the piping of the exhaust pipe 31 is branched and connected to the exhaust heat exchanger 70. You can For this reason, it is only necessary to provide a minimum number of pipes, and a significant increase in component costs can be suppressed.

  Further, according to the thermoelectric warming-up device 51 of the present embodiment, the ECU 7 can appropriately control the cooling water pipe on / off valve 63 and the lubricating oil pipe on / off valve 64, so that the flow rates of the cooling water W and the lubricating oil O are respectively set. It can be optimized to achieve optimal warm-up. In particular, after the warm-up operation is completed, power can be generated with a temperature difference between the exhaust gas G and the cooling water W by controlling the lubricating oil pipe opening / closing valve 64 to suppress the flow rate of the lubricating oil O.

  Further, according to the thermoelectric warm-up device 51 of the present embodiment, the ECU 7 controls the controller 8 to energize the thermoelectric conversion element 80 by the battery 6 connected to the thermoelectric conversion element 80 during the warm-up operation. Thus, the amount of heat transferred from the exhaust heat exchanger 70 to the warmer 60 can be increased. This is because heat is transferred by the Peltier effect. For example, a heat transfer amount that is twice or more that of heat conduction alone can be obtained.

  Further, according to the thermoelectric warm-up device 51 of the present embodiment, power is supplied using the battery 6 during the warm-up operation, whereas electric power is generated by the thermoelectric conversion element 80 after the warm-up operation ends. The charged electric power can be charged to the battery 6. Thus, for example, unlike the case where the alternator is used to charge the battery 6 when the vehicle 1 is traveling, the battery 6 can be charged without using the alternator, so that the fuel for driving the internal combustion engine 2 is consumed. The fuel consumption can be improved.

  In the thermoelectric warming device 51 of this embodiment described above, the amount of heat transferred from the exhaust heat exchanger 70 to the warmer 60 is increased by energizing the thermoelectric conversion element 80 by the battery 6 during the warming-up operation. However, the present invention is not limited to this. For example, the thermoelectric conversion element 80 may not be energized.

  Moreover, in the thermoelectric warming-up apparatus 51 of this Embodiment mentioned above, about the case where it heat-generates with the thermoelectric conversion element 80 with the temperature difference of the warmer 60 and the exhaust heat exchanger 70, and charges the battery 6 after warming-up operation. Although explained, it is not limited to this. For example, the battery 6 may not be charged.

  The present embodiment includes at least the following configuration. The thermoelectric warming device (51) of the present embodiment includes a thermoelectric conversion element (80) that forms a temperature difference between the first surface (83) and the second surface (84) by energization, and cooling water. It has a cooling water pipe (61) for circulating (W) and a lubricating oil pipe (62) for circulating lubricating oil (O), and the lubricating oil (O) can be heated by the heat of the heated cooling water (W). A first heat exchanger (60) and a second heat exchanger (70) capable of transferring heat by transferring the heat of the exhaust gas (G), of the thermoelectric conversion element (80). The first surface (83) and the first heat exchanger (60) are provided in contact with each other so as to be capable of conducting heat, and the second surface (84) of the thermoelectric conversion element (80) and the It is provided in contact with the second heat exchanger (70) so as to be able to conduct heat. According to this configuration, since the first heat exchanger (60) having the cooling water pipe (61) and the lubricating oil pipe (62) is provided in contact with the thermoelectric conversion element (80), the exhaust gas (G ) Is conducted from the exhaust pipe (31) to the lubricating oil pipe (62) of the first heat exchanger (60) through the thermoelectric conversion element (80). Thereby, compared with the case where the heat of exhaust gas (G) is conducted from the exhaust pipe (31) to the lubricating oil (O) through the thermoelectric conversion element (80) and further through the cooling water (W), the exhaust gas is discharged. The heat transfer efficiency from (G) to lubricating oil (O) can be improved.

  Further, in the thermoelectric warming-up device (51) of the present embodiment, during the warming-up operation, the thermoelectric conversion element (80) is energized by the battery (6) connected to the thermoelectric conversion element (80). As a result, the amount of heat transfer from the second heat exchanger (70) to the first heat exchanger (60) is increased. According to this structure, compared with the case of only heat conduction, for example, a heat transfer amount that is twice or more can be obtained, and the heat transfer efficiency from the exhaust gas (G) to the lubricating oil (O) can be further improved. .

  Further, in the thermoelectric warm-up device (51) of the present embodiment, the temperature difference between the first heat exchanger (60) and the second heat exchanger (70) is caused after the warm-up operation. Electric power is generated by the thermoelectric conversion element (80). According to this configuration, the battery (6) can be charged without using the alternator, unlike the case where the battery (6) is charged using the alternator when the vehicle (1) is traveling. Fuel consumption can be improved without consuming fuel for driving the engine (2).

  Further, the vehicle drive device (5) of the present embodiment includes the thermoelectric warm-up device (51) described above and the on-off valve (64) that can open and close the lubricating oil pipe (62). According to this configuration, since the ECU can appropriately control the on-off valve (64), it is possible to optimize the flow rate of the lubricating oil (O) and realize an optimal warm-up. In particular, after the warm-up operation is completed, the on-off valve (64) is controlled to suppress the flow rate of the lubricating oil (O), thereby generating power by the temperature difference between the exhaust gas (G) and the cooling water (W). can do.

  Further, the vehicle drive device (5) of the present embodiment includes a transmission mechanism (50) driven by the internal combustion engine (2), and the cooling water (W) cools the internal combustion engine (2), The lubricating oil (O) lubricates the transmission mechanism (50). According to this configuration, in the vehicle (1) equipped with the internal combustion engine (2) and the speed change mechanism (50), the heat transfer efficiency from the exhaust gas (G) to the lubricating oil (O) can be improved.

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Internal combustion engine 5 Vehicle drive device 6 Battery 50a Automatic transmission mechanism (transmission mechanism)
51 Thermoelectric warming device 60 Warmer (first heat exchanger)
61 Cooling water pipe 62 Lubricating oil pipe 64 Lubricating oil pipe open / close valve (open / close valve)
70 Exhaust heat exchanger (second heat exchanger)
80 Thermoelectric conversion element 83 First surface 84 Second surface G Exhaust gas O Lubricating oil W Cooling water

Claims (5)

A thermoelectric conversion element that forms a temperature difference between the first surface and the second surface by energization;
A first heat exchanger having a cooling water pipe for circulating cooling water and a lubricating oil pipe for circulating lubricating oil, and capable of heating the lubricating oil by heat of the heated cooling water;
A second heat exchanger that transfers heat of the exhaust gas and enables heat exchange;
The first surface of the thermoelectric conversion element and the first heat exchanger are provided in contact with each other so as to conduct heat, and the second surface of the thermoelectric conversion element and the second heat exchanger are provided. Is a thermoelectric warm-up device provided in contact with heat conduction.   In the warm-up operation, the amount of heat transferred from the second heat exchanger to the first heat exchanger is increased by energizing the thermoelectric conversion element by a battery connected to the thermoelectric conversion element. The thermoelectric warm-up device according to claim 1.   The thermoelectric warm-up device according to claim 2, wherein after the warm-up operation, the thermoelectric conversion element generates electric power due to a temperature difference between the first heat exchanger and the second heat exchanger. The thermoelectric warm-up device according to any one of claims 1 to 3,
An on-off valve capable of opening and closing the lubricating oil pipe. A transmission mechanism driven by an internal combustion engine;
The vehicle drive device according to claim 4, wherein the cooling water cools the internal combustion engine, and the lubricating oil lubricates the transmission mechanism.

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