Preheating fuel pipe of diesel engine
Technical field
The present invention relates to a kind of internal-combustion engine Preheating unit, particularly a kind of preheating fuel pipe of diesel engine.
Background technique
The low temperature flow of diesel oil is poor, the condensation point height.Under the cryogenic conditions, diesel engine cold start-up difficulty.May contain moisture in the diesel oil simultaneously, it is stifled to produce ice under low temperature environment, and oil supply system can't be the cold start-up fuel feeding.In order to guarantee that diesel engine can come into operation safely under cold environment, the low temperature auxiliary actuating apparatus has obtained using widely.The common mode that is used to improve the diesel engine low-temperature startup performance has three kinds, is respectively preheating machine oil, pre-hot cylinder and improves flowability of diesel oil, and wherein preceding two kinds of methods only just can work under diesel oil can keep the prerequisite of flowability.Have a kind of approach that improves the diesel oil at low-temperature flowability to be to use low freezing point diesel fuel at present, yet because the low freezing point diesel fuel price is higher, the diesel engine user cost also can increase.Even if the use low freezing point diesel fuel, diesel oil viscosity is still bigger under low temperature environment, the sparger injection can occur and run through little, the shortcoming thick, atomization and vaporization of spraying of length.
The another kind of approach that improves flowability of diesel oil is directly to heat diesel oil.As the patent No. is disclosed among the CN93236032.7 " diesel engine low-temperature startup device ", it discloses a kind of diesel engine Preheating unit, in the transport pipe of original diesel engine starting drive, install the PTC assembly of certain resistance additional, utilize its positive-coefficient thermistor characteristic heated fuel oil.But this kind startup auxiliary device also has shortcoming: at first, because the restriction of ptc material minimum dimension cooperates comparatively difficulty with the fuel pipe of diesel engine regular size, cause that the flowability of diesel oil in the pipe descends; Secondly, because the more crisp frangibility of ptc material, heating region sporadicly disperses, and its functional reliability is not high.
Summary of the invention
At the problems referred to above, in order to overcome the cold start-up difficulty that existing diesel engine causes because of working environment cold, the invention provides a kind of novel diesel oil preheating device, it utilizes the heating executive component in the fuel pipe directly to heat diesel oil, realizes easily at short notice starting smoothly.
Purpose of the present invention realizes by following technological scheme: a kind of preheating fuel pipe of diesel engine is provided, and it comprises fuel pipe body, heating executive component, control unit, sensor, work alarm element, seal element.
Preferably described heating executive component comprises at least one electric heating wire, and its manufacturing is simple, with low cost, flow resistance is little, and is higher for the versatility of each model diesel engine fuel oil pipeline; A kind of replacement scheme is to select a slice ribbon heater at least for use, and its advantage is that heat transfer area is big, and rate of heating is very fast; Another kind of alternative is to select at least one electrical bar for use, and its advantage is that heating value is big, and rate of heating is also very fast.In most preferred embodiment of the present invention, described heating executive component comprises three electric heating wire.Curved when every electric heating wire is connected with wiring terminal have certain radian, makes electric heating wire be in the positive center of fuel pipe inside, so both helped homogeneous heating, can avoid electric heating wire bonding risk of short-circuits again.Electric heating wire preferably adopts the nichrome material, and it has advantage corrosion-resistant, heat-resisting, that plasticity is good, can guarantee the reliability of electric heating wire work for a long time.
Preferably described control unit has at least one single-chip microcomputer.In most preferred embodiment of the present invention, described control unit has aviation rank single chip computer AT 89C2051, and its volume is small and exquisite, antijamming capability is strong, low-temperature working is stable, is suitable for the bad working environments at the motor of cold district's operation.
Preferably described work alarm element has luminous alarm, and it can be positioned in the instrument panel, makes the work alarm signal more directly perceived, is easy to driver's observation; A kind of replacement scheme is to select buzzer for use, and its advantage is little to the instrument panel change, and the equipment later stage is installed additional comparatively convenient.In most preferred embodiment of the present invention, described work alarm element has light emitting diode, and it has the advantage that volume is little, energy consumption is low, reliability is high.
Preferably, described sensor comprises semiconductor thermistor formula temperature transducer, and its volume is little, cost is low, reliability is high; A kind of replacement scheme is to select platinum resistance temperature sensor for use, and it has specific resistance and varies with temperature linear advantage.In most preferred embodiment of the present invention, described sensor comprises six thermistor temperature sensors, and every section pipe is equipped with two sensors.Can avoid the single-sensor inefficacy like this and cause diesel oil preheating out of control.
Preferably, seal element material adopts teflon, and it has good ageing resistance, corrosion resistance, sealing, electrical insulating property.In most preferred embodiment of the present invention, described seal element comprises some sealing gaskets and seal ring.
Preheating fuel pipe of diesel engine of the present invention is preferred for truck and the engineering machinery in cold district's operation.Compare with middle-size and small-size civilian vehicle, the truck and the engineering machinery of cold district's operation are seldom put into the garage, so difficulty more during cold start-up.Truck and engineering machinery are the tools of production, and its performance deficiency will directly influence economic benefit
Because comparing with the existing diesel Preheating unit, preheating fuel pipe of diesel engine of the present invention adopts directly heated fuel oil design in the pipe, heat energy utilization ratio height, and cold start-up greatly reduces required preheat time; Secondly, the heating activator structure is simple, the reliability height, and versatility is good, and is cheap; Use single-chip microcomputer that temperature is controlled automatically in addition, avoided the situation of artificial incorrect operation, by energy-conservation accurately controlling realization heating time.
Description of drawings
In order to make the present invention be more convenient for understanding, most preferred embodiment of the present invention is described in conjunction with the accompanying drawings now.
Fig. 1 is the schematic representation of arbitrary section fuel pipe of the most preferred embodiment of preheating fuel pipe of diesel engine of the present invention.
Fig. 2 is the partial sectional view at fuel pipe wiring terminal position embodiment illustrated in fig. 1.
Reference character: 1-fuel pipe body, 2-electric heating wire positive terminal, 3-battery positive voltage, the 4-single-chip microcomputer, the luminous alarm of 5-, 6-temperature transducer, 7-electric heating wire negative terminal, the 8-oil connection, 9-wiring terminal pilot hole, 10-be to jacking nut, the 11-seal element, 12-sensor pilot hole, 13 electric heating wire
Embodiment
Accompanying drawing shows the most preferred embodiment of preheating fuel pipe of diesel engine of the present invention.As shown in the figure, have wiring terminal pilot hole 9 on the fuel pipe body 1, a side joint terminal 2 is connected with electric heating wire 13 with 7 in pipe, and a side joint terminal 2 and 7 relies on jacking nut 10 is locked outside pipe.Wiring terminal 2 and 7 and the gap of its pilot hole 9 rely on seal element 11 sealings, to reach the non-leakage requirement of diesel oil.Battery positive voltage 3 links to each other with single-chip microcomputer 4, and the Preheating unit assembly is powered.Car battery is generally 12V or 24V output voltage, and the present invention directly adopts above-mentioned voltage to electric heating wire 13 heating.Three electric heating wire lay respectively at fuel tank between the fuel filter, fuel filter between the low pressure fuel pump, low pressure fuel pump is to the fuel pipe between the high pressure oil pump.On the fuel pipe body 1 of the positive terminal 2 of electric heating wire 13 and position, negative terminal 7 next door, have 12, one temperature transducers of sensor pilot hole 6 and gather the fuel oil temperature data by a sensor pilot hole 12.Also rely on seal element 11 sealings between fuel pipe body 1 and the temperature transducer 6, to reach the non-leakage requirement of diesel oil.The temperature sensor signal output terminal links to each other with single-chip microcomputer 4, and single-chip microcomputer 4 is according to the connecting and disconnecting of the circuit of the temperature signal control electric heating wire 13 that receives.When Preheating unit broke down, power circuit was cut off automatically, prevented various contingencies.Single-chip microcomputer 4 links to each other with luminous alarm 5, controls the break-make of luminous alarm.When Preheating unit heated, alarm 5 continued luminous; After Preheating unit stopped heating, alarm 5 light extinguished; If the Preheating unit fault, alarm 5 flickers are luminous.In order to increase the device safety in utilization, alarm 5 flicker luminescent methods hinder the difference of type and difference for some reason, and being divided into oil pipe does not have that oil is reported to the police, sensor failure is reported to the police and oily warm warning out of control.
Those skilled in the art are not difficult to find out that preheating fuel pipe of diesel engine of the present invention is not only applicable to truck and engineering machinery, but also can be used as the startup auxiliary device of the diesel engine of middle-size and small-size civilian vehicle.
Abovely describe in detail in conjunction with the preferred embodiments of the present invention, but this is not a limitation of the present invention, every technical spirit according to the present invention program is to any simple modification that above embodiment did, and equivalent variations and modification all still belong in the present invention program's the scope.