JPH1122603A - Combustion heating system of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obviate an exclusive pump to effectively operate a combustion heater, and attain weight reduction and size reduction in an engine by supplying at least a part of fuel sucked from a fuel tank by a fuel pump from the fuel pump as warming-up fuel. SOLUTION: A high pressure pump 36 to supply high pressure fuel from a low pressure pump 34 and a fuel tank 28 to an injection 11, is provided in a fuel supply ring passage 30 arranged in a fuel passage to connect the fuel tank 28 of a diesel engine 1 and a delivery pipe of the injection 11. Fuel from the fuel tank 28 is also supplied to a combustion heater 17 by the low pressure pump 34 by a branch pipe 32 which is arranged in a proper part 30a positioned on the downstream side of the low pressure pump 34 between both pumps 34 and 36 as well as on the upstream side of the high pressure pump 36 and extends toward the combustion heater 17. Therefore, a fuel supply pump exclusive to the combustion heater 17 can be obviated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion-type heating device for an internal combustion engine, and more particularly to a combustion-type heating device for an internal combustion engine that improves startability of the internal combustion engine in a cold state.

[0002]

BACKGROUND OF THE INVENTION Since internal combustion engines are designed to operate well over a certain temperature range, overheating is poor but overcooling is undesirable.

[0003] In the overcooled state, the temperature of the entire internal combustion engine is low, so that the fuel is difficult to vaporize or ignite, or the combustion speed is reduced. Also,
Since the clearance of each component constituting the internal combustion engine is designed to be just right in an assumed temperature range, a gap between the components is too large in a low temperature state out of the temperature range. For example, in terms of the relationship between a cylinder and a piston, if the gap between the two is large, an air-fuel mixture or combustion gas will blow out from the gap, and if there is a large clearance between other parts, the rotating and sliding parts Phenomenon such as being hit by the like easily occurs.

Further, in the overcooled state, the temperature of the engine oil is low, so that the viscosity thereof is high, and therefore the friction increases. For the above reasons, in the overcooled state, the inherent power and throttle response of the internal combustion engine cannot be expected, and if a large load is applied in the overcooled state, the internal combustion engine may be damaged.

[0005] Therefore, it is necessary to warm up the internal combustion engine immediately after starting, and it is necessary to quickly warm up the internal combustion engine. Therefore, for example, Japanese Patent Application Laid-Open No. Hei 2-271075 discloses a technique that promotes warm-up and enhances the startability of an engine in an overcooled state. This technology is
A combustion type heater is provided in the middle of the cooling water circulation passage, and the cooling water is heated by the combustion type heater prior to the start of the engine, and the heated cooling water is circulated through the water jacket of the engine to warm the engine body. That is.

[0006]

By the way, in this technique, the combustion type heater burns fuel in a combustion chamber provided in a housing thereof and heats cooling water by heat at that time. A special pump for guiding fuel from the combustion chamber to the combustion chamber is required.

For this reason, the entire engine may be increased in size and weight may be increased by the amount of the dedicated pump. The present invention has been made in view of the above points, and provides a combustion-type heating device for an internal combustion engine that does not require a dedicated pump for effectively functioning the combustion-type heater, and thus can reduce the size and weight of the engine. It is in.

[0008]

In order to solve the above-mentioned problems, a combustion-type heating apparatus for an internal combustion engine according to the present invention has the following configuration.

That is, the combustion-type heating apparatus for an internal combustion engine of the present invention supplies the fuel sucked by a fuel pump from a fuel tank to a combustion chamber and burns the fuel to promote the warm-up of the internal combustion engine. In a combustion type heating device for heating a component of an engine by using a fuel combustion means for performing combustion different from combustion in the combustion chamber, the fuel combustion means includes a fuel pump sucked from the fuel tank by the fuel pump. Is supplied from the fuel pump as at least a part of the fuel for warm-up.

In the combustion type heating device for an internal combustion engine according to the present invention,
The fuel pump not only supplies fuel to the combustion chamber so that the internal combustion engine obtains power, but also supplies at least a part of the fuel sucked from the fuel tank to the fuel combustion means as warm-up fuel. . In other words, the fuel pump is a pump that supplies fuel to the combustion chamber of the internal combustion engine in order to obtain the power of the internal combustion engine, and is also a pump that supplies fuel to fuel combustion means for efficiently warming up the engine. Therefore, a dedicated fuel supply pump is not required for a fuel heater, for example, a combustion type heater which has been required until now. Therefore, the internal combustion engine is reduced in weight and size accordingly.

Further, as a component of the internal combustion engine heated by the fuel combustion means, it is desirable to use cooling water for originally cooling the internal combustion engine. Further, the internal combustion engine is used for a vehicle, and the cooling water can be used as a heat source for an indoor heater of the vehicle.

The fuel pump includes a low-pressure pump for pressurizing the fuel in the fuel tank, and a high-pressure pump for pressurizing the fuel passing through the low-pressure pump to a high pressure. The fuel in the fuel tank may be supplied to the fuel combustion means from a fuel passage. In general, combustion by the fuel combustion means used for warming-up is combustion at atmospheric pressure, and a low-pressure pump is easier to adjust the pressure between a high-pressure pump and a low-pressure pump. In order to adjust the pressure with a high-pressure pump, pressure adjusting means is necessary because the fuel pressure is too high. Therefore, in order to adjust the pressure of the fuel supplied to the fuel combustion means, a low-pressure pump that can easily adjust the pressure is preferable.

In the combustion type heating device for an internal combustion engine according to the present invention,
The low pressure pump is located closer to the fuel tank than the high pressure pump. That is, it is on the upstream side. The fuel in the fuel tank is supplied to the fuel combustion means from a fuel passage provided between the low-pressure pump and the high-pressure pump. Therefore, the fuel can be supplied to the fuel combustion means while adjusting the pressure under the low pressure of the low-pressure pump that can easily adjust the pressure.

Further, a plurality of fuel supply devices for directly supplying the fuel sucked by the fuel pump to the combustion chamber in accordance with the number of cylinders of the internal combustion engine are provided, and the plurality of fuel supply devices are provided downstream of the fuel pump. A branch branch pipe for supplying fuel to each of the devices is provided, and the fuel is provided by a communication passage connecting the fuel passage with a fuel passage located upstream of the branch branch pipe and downstream of the fuel pump. The fuel sucked by the pump may be supplied to the fuel combustion means as warm-up fuel.

In this way, if the pressure in the fuel passage before reaching the branch branch decreases due to any cause, the fuel pressure is reduced regardless of the branch portion of the branch branch. Is uniformly reduced, and only a part of the branched portions is not reduced. For this reason, there is no possibility that only the fuel pressure of a specific cylinder decreases and combustion there deteriorates.

[0016]

Embodiments of the present invention will be described below with reference to the accompanying drawings. <First Embodiment> A description will be given with reference to FIG.

A piston 3 is vertically movable in a cylinder bore 2a formed in a cylinder block 2 of a diesel engine 1 as an internal combustion engine. Also,
The piston 3 is connected to a crankshaft via a connecting rod 4. The diesel engine 1 is mounted on a vehicle such as an automobile.

A combustion chamber recess 6 is formed in the piston head 3a. The recess 6 is hereinafter referred to as "combustion chamber". A cylinder head 7 is mounted and fixed on an upper portion of the cylinder block 2, and an intake port 8 and an exhaust port 9 facing the combustion chamber 6 are provided inside the cylinder head 7.

An intake valve 8a and an exhaust valve 9a are incorporated in the intake port 8 and the exhaust port 9, respectively. An injection 11 is disposed between the intake valve 8a and the exhaust valve 9a so as to face the combustion chamber 6.
Is injected into the fuel.

The injection 11 pumps an appropriate amount of high-pressure fuel into the combustion chamber 6 at an appropriate time by an injection pump (not shown). A rotation speed sensor 11a for detecting the engine rotation speed is attached to the injection pump.

The intake port 8 is connected to an intake pipe 8b, and the exhaust port 9 is connected to an exhaust pipe 9b. A throttle valve 12 is incorporated in the intake pipe 8b, and its opening is detected by an idle switch (throttle sensor) 12a provided on a rotation shaft of the throttle valve 12.

Then, outside air is introduced into the intake port 8 from an air cleaner (not shown) through the intake pipe 8b, and fuel is injected from the injection 11 toward the combustion chamber 6, and a mixture of the injected fuel and the outside air is formed. Due to the high pressure when the air burns in the combustion process, the piston 3 moves down the cylinder bore 2 a and rotates the crankshaft via the connecting rod 4.

In the exhaust step, the exhaust valve 9a
Is opened, the combustion gas flows from the exhaust port 9 to the exhaust pipe 9.
b to the outside. An exhaust throttle valve 13 is provided in the exhaust pipe 9b. The exhaust throttle valve 13 is driven by drive means such as a drive motor (not shown). Note that the exhaust throttle valve 13 is also similar to the throttle valve 12,
There is a sensor to detect the opening degree,
It is omitted here.

The exhaust port 9 corresponds to the portion of the cylinder head 7 where the exhaust throttle valve 13 is provided.
A cooling water passage 14 is formed therearound. Cooling water passage 14
Are formed not only around the exhaust port 9 but also around the intake port 8 and around the cylinder bore 2a in the cylinder block 2. Of these cooling water passages 14, at least the cooling water passage 14 around the exhaust port 9 is provided with a water temperature sensor 14a.

The rotation speed sensor 11a, idle switch 12a and water temperature sensor 14a are electrically connected to an engine electronic control unit (hereinafter referred to as "ECU") 16. The ECU 16 calculates the parameters output by the sensors 11a, 12a and 14a, thereby driving the driving means of the exhaust throttle valve 13. As a result, the exhaust throttle valve 13 is operated by the operating condition of the diesel engine 1. The valve is opened as appropriate.

Further, the diesel engine 1 is provided with a combustion heater 17 as a combustion heating device for heating cooling water in order to promote warm-up. Combustion heater 17
The cooling water inlet 18 and the cooling water outlet 20 provided in the cooling water passage 14 are annularly connected to each other, and the inside thereof is provided on an annular passage 22 through which the cooling water flows. It is also a department. Therefore, a cooling water passage 17a through which cooling water passes is formed in the combustion type heater 17, and the cooling water passage 17a is provided around a heater body 17b as a heat source.

Air other than the cooling water is sent to the combustion type heater 17 by an air pump 23. After this air is introduced into the inside of the combustion type heater 17 from the air inlet 17a of the combustion type heater 17, the heater body 17b
The fuel is burned by the flame. Then, the cooling water is heated by the air heated at this time. For this reason, the combustion type heater 17 is provided with an air passage 17c, the air passing through the air passage 17c is warmed by the heater body 17b, and the warmed air is used as a medium to warm the cooling water passing through the cooling water passage 17a. Can be Then, the cooled air is discharged to the outside of the combustion heater 17 as much as the cooling water is heated.

The combustion heater 17 used for warming up
Is performed under atmospheric pressure. In addition, annular route 2
2, a water pump 25 is disposed at a position near the cooling water inlet 18 provided in the cooling water passage 14, and a combustion heater 1 is provided between the water pump 25 and the combustion heater 17.
An indoor heater 26 is also provided at a position closer to 7.

While the cooling water is circulated in the annular passage 22 by the water pump 25, the cooling water is supplied to the combustion type heater 1.
7 heated. The heated cooling water promotes warm-up of the engine 1, and the cooling water is also used as a heat source of the indoor heater 26. The hot air from the indoor heater 26 is turned into hot air by the fan 26a.

A fuel supply passage 30 is provided in a fuel passage connecting a fuel tank 28 containing light oil or heavy oil, which is a driving fuel for the diesel engine 1, and a delivery pipe (not shown) of the injection 11.

A low-pressure pump 34 for pressurizing fuel in the fuel tank 28 and a low-pressure pump 34
And a high-pressure pump 36 that pressurizes the fuel sent from the fuel tank 28 to a high pressure and supplies the high-pressure fuel to the injection 11. Note that among these pumps, the low-pressure pump 34 is easier to adjust the pressure.

A branch pipe 32 is connected to the combustion heater 17 at an appropriate portion 30a between the two pumps 34 and 36, which is located downstream of the low pressure pump 34 and upstream of the high pressure pump 36. Extending towards.

The branch pipe 32 allows the fuel tank 28
Is supplied to the combustion heater 17 in addition to the combustion chamber 6 by the low-pressure pump 34, and is supplied to the combustion heater 17 for combustion. When the fuel is supplied to the combustion heater 17, the fuel is burned by the heater body 17b. A fuel amount control valve 37 for controlling the amount of fuel sent from the fuel tank 28 to the combustion heater 17 is interposed in the middle of the branch pipe 32.

Of the members described above, the combustion type heater 1
7, the annular passage 22, the water pump 25, the portion 30a of the fuel supply passage 30, the branch pipe 32, the low-pressure pump 34, the coolant, and the fuel containing at least the combustion of the internal combustion engine according to the first embodiment. It is a type heating device A. <Operation and Effect of First Embodiment> Next, the operation and effect of the combustion heating apparatus A for an internal combustion engine configured as described above will be described.

In the combustion type heating apparatus A for an internal combustion engine according to the first embodiment, the low pressure pump 34 is a pump for supplying fuel to the combustion chamber 6 of the diesel engine 1 in order to obtain the power of the diesel engine 1. It is also a pump that supplies fuel to the combustion heater 17 for efficiently warming up. Therefore, a dedicated fuel supply pump is not required for the combustion heater 17. Therefore, the weight and size of the diesel engine 1 are reduced accordingly.

Further, fuel is supplied to the combustion heater 17 from a portion 30a provided between the low pressure pump 34 and the high pressure pump 36. The combustion by the combustion heater 17 used for warming-up is combustion at atmospheric pressure, and the high-pressure pump 36 and the low-pressure pump 34 are easier to adjust the pressure than the high-pressure pump 36. , The fuel pressure is too high and requires pressure adjustment means. Therefore, in order to adjust the pressure of the fuel supplied to the combustion type heater 17, it is more preferable that the pressure is reduced under a low pressure by the low pressure pump 34 in which the pressure is easily adjusted.

Further, in the combustion type heating device A for an internal combustion engine, the low pressure pump 34 is located closer to the fuel tank 28 than the high pressure pump 36. That is, it is on the upstream side. The fuel in the fuel tank 28 is supplied to the combustion heater 17 from a branch pipe 32 which is a fuel passage provided between the low-pressure pump 34 and the high-pressure pump 36. That is, at least a part of the fuel sucked from the fuel tank 28 by the low-pressure pump 34 is supplied from the low-pressure pump 34 as warm-up fuel. Therefore, the fuel is preferably supplied to the combustion heater 17 while the pressure is adjusted under the low pressure of the low-pressure pump 34, which can easily adjust the pressure.

The present invention is not limited to the above embodiment. That is, a part of the configuration can be appropriately changed as long as it does not deviate from the gist of the invention, and the following second and third embodiments can be adopted. <Second Embodiment> A combustion type heating device B for an internal combustion engine according to a second embodiment will be described with reference to FIG.

The combustion type heating device B for an internal combustion engine according to the second embodiment is different from the combustion type heating device A for an internal combustion engine according to the first embodiment in that a low pressure pump 34 is used instead of the low pressure pump 34. Only the point where the feed pump 44 is provided and the portion related thereto. For this reason, different portions will be described, and the same portions will be denoted by the same reference numerals and description thereof will be omitted. It should be noted that the cylinder block 2 of the diesel engine 1 is schematically illustrated.

In the combustion type heating apparatus B for an internal combustion engine according to the second embodiment, a low pressure feed pump 44 is provided coaxially in a housing 36a of a high pressure pump 36.
Further, between the feed pump 44 and the high-pressure pump 36, there is a communication passage 46 equivalent to the portion 30a described in the above embodiment. A branch pipe 32A equivalent to the branch pipe 32 described in the above-described embodiment is provided at a substantially intermediate position of the communication passage 46.

Further, the combustion type heater 17, the annular path 22,
Water pump 25, portion 30a of fuel supply circuit 30,
A combustion heating device B for an internal combustion engine according to the second embodiment includes at least the branch pipe 32, the feed pump 44, the cooling water, and the fuel. The combustion-type heating device B for an internal combustion engine according to the second embodiment has the same operation and effect as the combustion-type heating device A for an internal combustion engine according to the first embodiment. <Third Embodiment> A combustion type heating apparatus C for an internal combustion engine according to a third embodiment will be described with reference to FIG.

The combustion heating device C for an internal combustion engine according to the third embodiment is different from the combustion heating devices A and B for the internal combustion engine according to the first and second embodiments. ,
This is a change accompanying the change of the engine to the gasoline engine 1B. Therefore, the same portions as those of the combustion type heating devices A and B of the internal combustion engine according to the first and second embodiments are denoted by the same reference numerals, and description thereof will be omitted. Note that the cylinder block 2 of the gasoline engine 1B is schematically illustrated.

Since the engine is a gasoline engine, a spark plug 47 is provided in the gasoline engine 1B, and a combustion chamber 6A is formed in the cylinder head 7 instead of the piston 3 having no combustion chamber 6.

Further, the injection port 1 is connected to the intake port 8.
1C, and an electromagnetic pump 48 is used instead of the low-pressure pump 34 or the feed pump 44 and the high-pressure pump 36 used in the first and second embodiments. In addition,
In the case of a gasoline engine, since the fuel injection pressure is lower than that of a diesel engine, the fuel is directly pumped to the injection 11C.

Further, the branch pipe 32 and the branch pipe 32B equivalent to the branch pipe 32A described in the first embodiment and the second embodiment are connected to each other as a fuel passage between the electromagnetic pump 48 and the injection 11C. It was provided in the passage 50. The communication passage 50 is connected to the fuel supply circuit 30 according to the first embodiment.
Is equivalent to the portion 30a.

The gasoline engine 1B has a plurality of cylinder blocks 2, and accordingly, a plurality of injections 11C. Further, the branch pipes 52 branched on the side of the injection 11C in accordance with the number of the injections 11C are connected to the tip of the communication passage 50 in an oblique state. In this embodiment, since only one cylinder block 2 is shown, only one branching state of the ignition plug 48, the injection 11C, and the branch branch pipe 52 is shown.

Further, the combustion type heater 17, the annular path 22,
The combustion heating device C for an internal combustion engine according to the third embodiment includes at least the water pump 25, the communication passage 50, the branch pipe 32B, the electromagnetic pump 48, the branch branch pipe 52, the cooling water, and the fuel. .

The combustion heating device C for the internal combustion engine according to the third embodiment has the same operation and effect as the combustion heating devices A and B for the internal combustion engine according to the first and second embodiments. It has the following functions and effects.

That is, in the combustion type heating apparatus C for an internal combustion engine according to the third embodiment, the injection 11C for directly supplying the fuel sucked by the electromagnetic pump 48 to the combustion chamber 6A is used for the cylinder block 2 of the gasoline engine 1B. A plurality is provided according to the number. The electromagnetic pump 4
8, a branch branch pipe 52 for supplying fuel to each of the plurality of injections 11C is provided.
The fuel sucked by the electromagnetic pump 48 through the branch pipe 32B, which is a communication passage connecting the communication heater 50 and the communication passage 50 located at a position further upstream than the electromagnetic pump 48 and downstream of the electromagnetic pump 48, is burned as warm-up fuel. The power is supplied to the heater 17.

For this reason, when the pressure decreases before reaching the branch branch pipe 52, the fuel pressure is reduced uniformly regardless of the branch part of the branch branch pipe 52, and only a part of the branch part is reduced. I won't. Therefore, there is no possibility that only the fuel pressure of the specific cylinder block 2 drops and the combustion there deteriorates.

[0051]

As described above, in the combustion type heating apparatus for an internal combustion engine according to the present invention, the fuel pump not only supplies the fuel to the combustion chamber for the internal combustion engine to obtain power, but also
The fuel pump supplies at least a part of the fuel drawn from the fuel tank to the fuel combustion means as warm-up fuel.
In other words, the fuel pump is a pump that supplies fuel to the combustion chamber of the internal combustion engine in order to obtain the power of the internal combustion engine, and is also a pump that supplies fuel to fuel combustion means for efficiently warming up the engine. Therefore, a dedicated fuel supply pump is not required for a fuel heater, for example, a combustion type heater which has been required until now. Therefore, the internal combustion engine is reduced in weight and size accordingly.

[Brief description of the drawings]

FIG. 1 is a conceptual configuration diagram of a diesel engine employing a combustion-type heating device for an internal combustion engine according to a first embodiment of the present invention.

FIG. 2 is a conceptual configuration diagram of a diesel engine employing a combustion-type heating device for an internal combustion engine according to a second embodiment of the present invention.

FIG. 3 is a conceptual configuration diagram of a diesel engine employing a combustion-type heating device for an internal combustion engine according to a third embodiment of the present invention.

[Explanation of symbols]

 A: combustion type heating device for an internal combustion engine according to the first embodiment B: combustion type heating device for an internal combustion engine according to the second embodiment C: combustion type heating for an internal combustion engine according to the third embodiment Apparatus 1 ... Diesel engine 1B ... Gasoline engine 2 ... Cylinder block 2a ... Cylinder bore 3 ... Piston 3a ... Piston head 4 ... Connecting rod 6 ... Combustion chamber 7 ... Cylinder head 8 ... Intake port 8a ... Intake valve 8b ... Intake pipe 9 ... Exhaust port 9a: Exhaust valve 9b: Exhaust pipe 9c: Inner surface of exhaust port 9 11: Injection 11C: Injection 11a: Rotation speed sensor 12: Throttle valve 12a: Idle switch (throttle sensor) 13: Exhaust throttle valve (exhaust throttle means) 14 ... Cooling water passage 14A ... Cooling water passage 14a ... Water temperature sensor 16 ... ECU 1 .. Combustion heater 17a Cooling water passage 17b Heater body 17c Air passage 18 Cooling water inlet 20 Cooling water outlet 22 Annular path 23 Air pump 25 Water pump 26 Indoor heater 26a Fan 28 Fuel Tank 30 ... Fuel supply circuit 32 ... Branch pipe 32A ... Branch pipe 32B ... Branch pipe 34 ... Low pressure pump 36a ... High pressure pump 36a ... High pressure pump housing 37 ... Fuel amount control valve 44 ... Feed pump 46 ... Communication path 47 ... Ignition Plug 48 ... Electromagnetic pump 50 ... Communication passage 52 ... Branch branch pipe

Claims (5)

[Claims] 1. A fuel supply system according to claim 1, further comprising: supplying a fuel sucked by a fuel pump from a fuel tank to a combustion chamber, and burning the fuel in the combustion chamber. In a combustion type heating apparatus for heating using a fuel combustion means for performing another combustion, the fuel combustion means uses at least a part of the fuel sucked from the fuel tank by the fuel pump as a fuel for warming up the fuel pump. A combustion-type heating device for an internal combustion engine. 2. The combustion of the internal combustion engine according to claim 1, wherein the component of the internal combustion engine heated by the fuel combustion means is cooling water for originally cooling the internal combustion engine. Type heating device. 3. The combustion-type heating device for an internal combustion engine according to claim 2, wherein the internal combustion engine is used for a vehicle, and the cooling water is used as a heat source for an indoor heater of the vehicle. . 4. The fuel pump includes a low-pressure pump for pressurizing fuel in the fuel tank, and a high-pressure pump for pressurizing fuel coming through the low-pressure pump to a high pressure. 4. The combustion type heating device for an internal combustion engine according to claim 3, wherein the fuel in the fuel tank is supplied to the fuel combustion means from a fuel passage provided. 5. A plurality of fuel supply devices for directly supplying the fuel sucked by the fuel pump to the combustion chamber in accordance with the number of cylinders of the internal combustion engine, and the plurality of fuel supply devices are provided downstream of the fuel pump. A branch branch pipe for supplying fuel to each of the plurality of branch branch pipes, and a communication passage connecting the fuel passage and the fuel combustion means located at a position upstream of the plurality of branch branches and downstream of the fuel pump. The combustion type heating device for an internal combustion engine according to claim 1, wherein the fuel sucked by the fuel pump is supplied to the fuel combustion means as a warm-up fuel.