CN201943792U - Engineering machinery, engine and piston cooling mechanism of engine - Google Patents

Engineering machinery, engine and piston cooling mechanism of engine Download PDF

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Publication number
CN201943792U
CN201943792U CN2010206927795U CN201020692779U CN201943792U CN 201943792 U CN201943792 U CN 201943792U CN 2010206927795 U CN2010206927795 U CN 2010206927795U CN 201020692779 U CN201020692779 U CN 201020692779U CN 201943792 U CN201943792 U CN 201943792U
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China
Prior art keywords
piston
cooling
oil
motor
cooling mechanism
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Expired - Lifetime
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CN2010206927795U
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Chinese (zh)
Inventor
孙少军
佟德辉
王洪山
董晓婷
朱杨
高焱
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Weichai Power Co Ltd
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Weichai Power Co Ltd
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Abstract

The utility model discloses a piston cooling mechanism of an engine, comprising an oil source of a cooling machine and a cooling nozzle (11), wherein an oil cooling channel (26) is arranged between the oil source of the cooling machine and the cooling nozzle, a pressure limiting valve (25) is arranged between the oil source of the cooling machine and the oil cooling channel (26) of the cooling machine, the inlet (256) of the pressure limiting valve (25) is communicated with the oil source of the cooling machine, the outlet (255) of the pressure limiting valve (25) is communicated with the oil cooling channel (26) of the cooling machine. The piston cooling mechanism of the engine of the utility model can control the cooling nozzle to eject the oil according to needs, under the condition of satisfying cooling requirements, the expansion of the piston and the piston ring is avoided, and carbon deposition formed by the insufficient burning of the cooling oil can be avoided. The utility model also discloses an engine comprising the piston cooling mechanism and engineering machinery comprising the engine.

Description

Engineering machinery, motor and piston cooling mechanism thereof
Technical field
The utility model relates to technical field of engineering machinery, particularly relates to a kind of piston cooling mechanism that is used for motor.In addition, the utility model also relates to a kind of motor and a kind of engineering machinery that comprises above-mentioned motor that comprises above-mentioned piston cooling mechanism.
Background technique
Motor is the power resources of various engineering machinery, mainly is to change mechanical energy into by the chemical energy with diesel oil or gasoline equal energy source to provide power for the running of engineering machinery.
In the course of the work, energy work by combustion promotes piston motion, and then the crankshaft rotating that is connected with piston of drive, and mechanical energy is passed.Yet because the continuous burning of the energy will inevitably produce a large amount of heats, too high in order to prevent the temperature in the piston, operated by rotary motion has cooling system.
In the prior art, mainly be by cooling jet is set on piston, and in piston, spray the purpose that machine oil reaches cooling piston by cooling jet.
Understand for convenient, be explained as follows existing partial correlation is belonged to:
Piston cooling nozzle: tubulose shower nozzle, cooling machine oil reach the purpose of cooling piston by its injection of realization in piston.
Oil filter: be used for Cress machine oil, filter out the device of impurities in the machine oil.
Carbon distribution: because of insufficient a large amount of soots and particle that in piston combustion bowl, forms that burn.
In the working procedure of motor, along with the motion of piston and the rotation of bent axle, piston cooling nozzle constantly sprays machine oil, cooling piston in piston; Yet, under the lower situation of engine speed when idling (particularly), the temperature of motor is generally lower, at this moment, if cool off, then be easy to cause piston and piston ring swell increment not enough, thereby make the gap between piston and the cylinder liner to eliminate, cause the generation of pinking and engine knock phenomenon; On the other hand, cooling machine oil also might be scurried and be participated in burning in the firing chamber, but is subjected to the influence of its characteristic, can not fully burn again, thereby form carbon distribution, even also can cause the generation of pull-cylinder phenomena; Further, because the pump output of machine oil also is subjected to the influence of rotating speed, when rotating speed is low, pump output is also less, in such cases, piston cooling nozzle will certainly further reduce oil pressure as a lubricating oil leakage point, thereby makes the lack of lubrication of part such as bearing shell, and then the generation of causing watt phenomenon.
Therefore, how to control cooling jet and spray machine oil as required, under the situation that satisfies the cooling needs, avoid influencing the expansion of piston and piston ring, and cooling machine oil burn incompletely formation carbon distribution, just become the present technical issues that need to address of those skilled in the art.
The model utility content
The purpose of this utility model provides a kind of piston cooling mechanism of motor, the piston cooling mechanism of this motor can be controlled cooling jet and spray machine oil as required, under the situation that satisfies the cooling needs, avoid influencing the expansion of piston and piston ring, and the cooling machine oil burn incompletely forms carbon distribution.Another purpose of the present utility model provides a kind of motor and a kind of engineering machinery that comprises above-mentioned motor that comprises above-mentioned piston cooling mechanism.
For solving the problems of the technologies described above, the utility model provides a kind of piston cooling mechanism of motor, comprise Coolers oil sources and cooling jet, be provided with the cooling machine oil passage between the two, also be provided with pressure-limit valve between described Coolers oil sources and the described cooling machine oil passage, the inlet of described pressure-limit valve is communicated with described Coolers oil sources, its outlet and described cooling machine oil channel connection.
Preferably, described pressure-limit valve comprises piston sleeve and is set in the interior piston body of described piston sleeve, offer described inlet and described outlet on the described piston sleeve, one end of described piston body is provided with spring, the parallel axes of described spring is in the axis of described piston body, described inlet and described spring lay respectively at the two ends of described piston body, described inlet and described outlet be communicated with or by.
Preferably, also offer oil leakaging port on the described piston sleeve, described oil leakaging port and described spring are positioned at the homonymy of described piston body, and described oil leakaging port is communicated with described Coolers oil sources by pipeline.
Preferably, compression spring, described compression spring and described piston body are arranged at the two ends of described spring respectively.
Preferably, also be provided with oil filter between described Coolers oil sources and the described pressure-limit valve.
Preferably, also be provided with machine oil cooler between described Coolers oil sources and the described oil filter.
For solving the problems of the technologies described above, the utility model also provides a kind of motor, comprises piston and piston cooling mechanism, the piston cooling mechanism that described piston cooling mechanism is above-mentioned each described motor.
Preferably, the number of the piston cooling mechanism of described motor is identical with the number of described piston.
For solving the problems of the technologies described above, the utility model also provides a kind of engineering machinery, comprises support device and the motor that is arranged at described support device, above-mentioned each the described motor of described motor.
The piston cooling mechanism of motor provided by the utility model, comprise Coolers oil sources and cooling jet, be provided with the cooling machine oil passage between the two, also be provided with pressure-limit valve between Coolers oil sources and the cooling machine oil passage, the inlet of pressure-limit valve is communicated with the Coolers oil sources, its outlet and cooling machine oil channel connection.Because the oil pressure in the cooling machine oil passage is relevant with the rotating speed of motor, rotating speed is high more, oil pressure is big more, the setting of pressure-limit valve, when making the rotating speed of motor reach predetermined value, pressure-limit valve is opened, cooling machine oil arrives cooling jet by pressure-limit valve and cooling machine oil passage, and spray in the piston by cooling jet, cooling piston, and at this moment, motor has reached within the operating range that allows, piston ring also reaches the swelling state that needs after being heated, reduced the gap between piston and the cylinder liner, and then reduced the machine oil of scurrying in the firing chamber; And before the rotating speed of motor reached the desired speed value, the temperature of motor was lower, need not to cool off, and closing of pressure-limit valve for other positions that need cool off have stored oil pressure, guaranteed the cooling effect at other position.As can be seen, the piston cooling mechanism of motor provided by the utility model can be controlled cooling jet and spray machine oil in appropriate circumstances, thereby under the situation that satisfies the cooling needs, avoid having influence on the expansion of piston and piston ring, can reduce the gap between piston and the cylinder liner apace, reduce noise and pinking, can also prevent that cooling machine oil from scurrying in the firing chamber simultaneously, the cooling machine oil burn incompletely occurs and form carbon distribution, finally cause the phenomenon of scuffing of cylinder bore.
In a kind of preferred implementation, the piston cooling mechanism of motor provided by the utility model also comprises oil filter, and oil filter is arranged between Coolers oil sources and the pressure-limit valve.Like this, oil filter can at first filter out the impurity in the machine oil, and then is ejected in the piston by cooling jet through pressure-limit valve and cooling machine oil passage, cools off, and has avoided the impurity in the machine oil to enter piston, influences the working life of piston.
The beneficial effect of engineering machinery provided by the utility model and motor is identical with the beneficial effect of the piston cooling mechanism of above-mentioned motor, repeats no more here.
Description of drawings
The structural representation of the piston cooling mechanism of the motor that Fig. 1 is provided for a kind of embodiment of the utility model;
Fig. 2 is the cross-sectional schematic of part-structure of the piston cooling mechanism of motor provided by the utility model;
Fig. 3 is the cross-sectional schematic of pressure-limit valve shown in Figure 2;
The structural representation of the part-structure of the motor that Fig. 4 is provided for a kind of embodiment of the utility model.
Embodiment
Core of the present utility model provides a kind of piston cooling mechanism of motor, the piston cooling mechanism of this motor can be controlled cooling jet and spray machine oil as required, under the situation that satisfies the cooling needs, avoid influencing the expansion of piston and piston ring, and the cooling machine oil burn incompletely forms carbon distribution.Another core of the present utility model provides a kind of motor and and a kind of engineering machinery that comprises above-mentioned motor that comprises above-mentioned piston cooling mechanism.
In order to make those skilled in the art person understand the utility model scheme better, the utility model is described in further detail below in conjunction with the drawings and specific embodiments.
Please refer to Fig. 1, the structural representation of the piston cooling mechanism of the motor that Fig. 1 is provided for a kind of embodiment of the utility model.
As shown in Figure 1, in a kind of embodiment, the piston cooling mechanism of motor provided by the utility model, comprise Coolers oil sources and cooling jet 11, be provided with cooling machine oil passage 26 between the two, also be provided with pressure-limit valve 25 between Coolers oil sources and the cooling machine oil passage 26, the inlet of pressure-limit valve 25 is communicated with the Coolers oil sources, and its outlet is communicated with cooling machine oil passage 26.Like this, through pressure-limit valve 25, cooling machine oil passage 26 arrived cooling jets 11 after the cooling machine oil that is used for cooling piston went out from the cooling machine oil source and course, via cooling jet 11 cooling machine oil was injected in the piston.
Because under the lower situation of engine speed, the temperature of motor is generally lower, at this moment, need not to cool off, if cool off, be easy to cause piston and piston ring swell increment not enough, gap between piston and the cylinder liner can't be eliminated and cause the situation of the generation of pinking and engine knock phenomenon; Simultaneously, owing to have the gap between piston and the cylinder liner, cooling machine oil is also probably scurried and is participated in burning in the firing chamber, thereby forms carbon distribution, causes the hidden danger of the generation of pull-cylinder phenomena; Further, because the pump output of cooling machine oil also is subjected to the influence of engine speed, rotating speed is high more, oil pressure is big more, and cooling machine oil not merely is to be used for cooling piston, also needs to cool off heating component such as bearing shell, and when rotating ratio is low, then not only can cause foregoing problem if cooling jet still sprays cooling machine oil in piston, also can cause the waste of the cooling machine oil of pumping to make the cooling and the lack of lubrication of parts such as bearing shell.
And the piston cooling mechanism of motor provided by the utility model, between cooling machine oil passage 26 and Coolers oil sources, be provided with pressure-limit valve 25, because oil pressure in the cooling machine oil passage 26 and rising constantly along with the rising of engine speed, and when the rotating ratio of motor hangs down, oil pressure in the cooling machine oil passage 26 does not reach the scheduled pressure value of pressure-limit valve 25, keep closed condition, not only can not influence the elimination in the gap between piston and the cylinder liner, but also guarantee the cooling effect of other parts that need cool off; And when the rotating speed of motor reaches predetermined value, pressure-limit valve 25 is opened, cooling machine oil arrives cooling jet 11 by pressure-limit valve 25 and cooling machine oil passage 26, and spray in the piston by cooling jet 11, cooling piston, and at this moment, motor has reached within the operating range that allows, piston ring also reaches the swelling state that needs after being heated, reduced the gap between piston and the cylinder liner, and then reduced the machine oil of scurrying in the firing chamber.
Certainly, in order to guarantee to enter on the basis of control of cold oil of piston 25 pairs of pressure-limit valves, do not influence the cooling of cooling machine oil to the motor miscellaneous part, cooling machine oil passage 26 as herein described is meant the oil passageway that is specifically designed to cooling piston, and the cooling machine oil that is used for the miscellaneous part of cooled engine circulates by body main oil gallery 12.
As can be seen, the piston cooling mechanism of motor provided by the utility model can be controlled cooling jet 11 and spray machine oil in appropriate circumstances, thereby under the situation that satisfies the cooling needs, avoid having influence on the expansion of piston and piston ring, can reduce the gap between piston and the cylinder liner apace, reduce noise and pinking, can also prevent that simultaneously cooling machine oil from scurrying in the firing chamber, the cooling machine oil burn incompletely occurs and form carbon distribution, finally cause the phenomenon of scuffing of cylinder bore, guarantee the cooling effect of each parts of motor under the various situations simultaneously.
In addition,, between Coolers oil sources and oil filter, also be provided with machine oil cooler 13, enter the temperature of the cooling machine oil in the cooling machine oil passage 26 with reduction in order to guarantee cooling effect.
Please refer to Fig. 2 and Fig. 3, Fig. 2 is the cross-sectional schematic of part-structure of the piston cooling mechanism of motor provided by the utility model; Fig. 3 is the cross-sectional schematic of pressure-limit valve shown in Figure 2.
As shown in FIG., in a kind of embodiment, the piston cooling mechanism of motor provided by the utility model also comprises oil filter 21, and oil filter 21 is arranged between Coolers oil sources and the pressure-limit valve 25.
As shown in Fig. 1 and Fig. 2, the cooling machine oil that goes out by the cooling machine oil source and course, enter machine oil oil inlet passage 22 through machine oil filler opening 23, entering oil filter 21 then filters, filtration is finished later machine oil and is flowed out from machine oil oil discharge passage 24, enters body main oil gallery 12 and cooling machine oil passage 26 respectively, certainly, to pass through pressure-limit valve 25 earlier, the break-make of limited valve 25 control cooling machine oil passages 26 entering between the cooling machine oil passage 26.
Like this, cooling machine oil at first passes through the filtration of oil filter 21, dispose the impurity in the machine oil, and then through respectively through parts such as body main oil gallery 12 cooling bearing shells, and pressure-limit valve 25 and cooling machine oil passage 26 are ejected in the piston by cooling jet 11, cooling piston has avoided the impurity in the machine oil to enter each parts of motor, influences the working life of motor.
As shown in Figure 3, in a kind of embodiment, the pressure-limit valve 25 of the piston cooling mechanism of motor provided by the utility model can comprise piston sleeve 251 and the piston body 252 that is set in the piston sleeve 251, offer inlet 256 and outlet 255 on the piston sleeve 251, one end of piston body 252 is provided with spring 253, the parallel axes of spring 253 is in the axis of piston body 252, and inlet 256 and spring 253 lay respectively at the two ends of piston body 252, inlet 256 and outlet 255 be communicated with or by.
Like this, in the course of the work, rotating speed rising along with motor, the oil pressure of cooling machine oil constantly raises, inlet 256 by pressure-limit valve 25 acts on piston body 252, piston body 252 is at the effect lower compression spring 253 of cooling machine oil, and constantly move to outlet 255 directions, when oil pressure reaches predetermined value, piston body 252 will export 255 and open, thereby make inlet 256 and outlet 255 be communicated with, and the cooling machine oil that enters via the inlet 256 of pressure-limit valve 25 flows out by outlet 255, enter cooling machine oil passage 26, realize the cooling of piston.As can be seen, above-mentioned pressure-limit valve 25 simple in structure, implementation procedure is convenient, has reduced user cost.
Further, also offer oil leakaging port 257 on the piston sleeve 251 of the pressure-limit valve 25 of the piston cooling mechanism of motor provided by the utility model, oil leakaging port 257 and spring 253 are positioned at the homonymy of piston body 252, and oil leakaging port 257 is communicated with the Coolers oil sources by pipeline.
In the course of the work, have the opposite side that the part cooling machine oil flow to piston body 252 unavoidably, if the Coolers oil mass of this side is too much, and cooling machine oil can't compress, and then can influence moving of piston body 252, in addition cause entering the mouth 256 and outlet 255 can't be communicated with, influence cooling effect, and then the working life of shortening motor, the cooling machine oil that the setting of oil leakaging port 257 then can be come seepage is directly carried back the Coolers oil sources, has avoided the appearance of above-mentioned situation.
Particularly, the setting of spring 253 for convenience makes things convenient for simultaneously the predetermined pressure of pressure-limit valve 25 is adjusted, and pressure-limit valve 25 provided by the utility model also comprises compression spring 254, and compression spring 254 and piston body 252 are arranged at the two ends of spring 253 respectively.Thereby, when needs increase predetermined pressure, then change thicker compression spring 254, otherwise, change thin compression spring 254, satisfied the needs of adjusting easily.
Piston cooling mechanism except above-mentioned motor, the utility model also provides a kind of motor, comprises piston and piston cooling mechanism, the piston cooling mechanism that this piston cooling mechanism is above-described motor, the structure of other each several parts of motor please refer to prior art, and this paper repeats no more.
Please refer to Fig. 4, the structural representation of the part-structure of the motor that Fig. 4 is provided for a kind of embodiment of the utility model.
In a kind of embodiment, the number of the piston cooling mechanism of motor is identical with the number of described piston.Thereby can guarantee the cooling effect of each piston of motor.
Further, except above-mentioned motor, the utility model also provides a kind of engineering machinery, comprise support device and the motor that is arranged on the support device, motor is above-mentioned motor, the structure and the prior art of other each several parts of engineering machinery are similar, please refer to prior art, and this paper repeats no more.
More than engineering machinery provided by the utility model, motor and piston cooling mechanism thereof are described in detail.Used specific case herein principle of the present utility model and mode of execution are set forth, above embodiment's explanation just is used for helping to understand method of the present utility model and core concept thereof.Should be understood that; for those skilled in the art; under the prerequisite that does not break away from the utility model principle, can also carry out some improvement and modification to the utility model, these improvement and modification also fall in the protection domain of the utility model claim.

Claims (9)

1. the piston cooling mechanism of a motor, comprise Coolers oil sources and cooling jet (11), be provided with cooling machine oil passage (26) between the two, it is characterized in that, also be provided with pressure-limit valve (25) between described Coolers oil sources and the described cooling machine oil passage (26), the inlet (256) of described pressure-limit valve (25) is communicated with described Coolers oil sources, and its outlet (255) is communicated with described cooling machine oil passage (26).
2. the piston cooling mechanism of motor according to claim 1, it is characterized in that, described pressure-limit valve (25) comprises piston sleeve (251) and is set in the interior piston body (252) of described piston sleeve (251), offer described inlet (256) and described outlet (255) on the described piston sleeve (251), one end of described piston body (252) is provided with spring (253), the parallel axes of described spring (253) is in the axis of described piston body (252), described inlet (256) and described spring (253) lay respectively at the two ends of described piston body (252), described inlet (256) and described outlet (255) be communicated with or by.
3. the piston cooling mechanism of motor according to claim 2, it is characterized in that, also offer oil leakaging port (257) on the described piston sleeve (251), described oil leakaging port (257) and described spring (253) are positioned at the homonymy of described piston body (252), and described oil leakaging port (257) is communicated with described Coolers oil sources by pipeline.
4. the piston cooling mechanism of motor according to claim 3 is characterized in that, compression spring (254), and described compression spring (254) and described piston body (252) are arranged at the two ends of described spring (253) respectively.
5. according to the piston cooling mechanism of each described motor of claim 1 to 4, it is characterized in that, also be provided with oil filter (21) between described Coolers oil sources and the described pressure-limit valve (25).
6. according to the piston cooling mechanism of each described motor of claim 1 to 4, it is characterized in that, also be provided with machine oil cooler (13) between described Coolers oil sources and the described oil filter (21).
7. a motor comprises piston and piston cooling mechanism, it is characterized in that the piston cooling mechanism that described piston cooling mechanism is each described motor of claim 1 to 6.
8. motor according to claim 7 is characterized in that, the number of the piston cooling mechanism of described motor is identical with the number of described piston.
9. an engineering machinery comprises support device and the motor that is arranged at described support device, it is characterized in that described motor is claim 7 or 8 described motors.
CN2010206927795U 2010-12-31 2010-12-31 Engineering machinery, engine and piston cooling mechanism of engine Expired - Lifetime CN201943792U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN2010206927795U CN201943792U (en) 2010-12-31 2010-12-31 Engineering machinery, engine and piston cooling mechanism of engine

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Application Number Priority Date Filing Date Title
CN2010206927795U CN201943792U (en) 2010-12-31 2010-12-31 Engineering machinery, engine and piston cooling mechanism of engine

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CN201943792U true CN201943792U (en) 2011-08-24

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102022173A (en) * 2010-12-31 2011-04-20 潍柴动力股份有限公司 Engineering machinery, engine and piston cooling mechanism thereof
CN105545443A (en) * 2015-12-31 2016-05-04 潍柴动力扬州柴油机有限责任公司 Piston cooling nozzle

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102022173A (en) * 2010-12-31 2011-04-20 潍柴动力股份有限公司 Engineering machinery, engine and piston cooling mechanism thereof
CN105545443A (en) * 2015-12-31 2016-05-04 潍柴动力扬州柴油机有限责任公司 Piston cooling nozzle

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Granted publication date: 20110824