CN201232593Y

CN201232593Y - Piston head structure for diesel engine

Info

Publication number: CN201232593Y
Application number: CNU2008201273218U
Authority: CN
Inventors: 宫宝利
Original assignee: China Automotive Engineering Research Institute Co Ltd
Current assignee: China Automotive Engineering Research Institute Co Ltd
Priority date: 2008-07-25
Filing date: 2008-07-25
Publication date: 2009-05-06
Anticipated expiration: 2018-07-25

Abstract

The utility model discloses a piston head structure of a diesel motor; the diameter of a piston is from 100mm to 120mm; the diameter of a combustion chamber with an Omega-shaped contraction end at the head of the piston is 60mm to 65mm; the diameter of the contraction end is 50mm to 60mm, and the depth is 20mm to 25mm and the contraction end angle is 40 degrees to 45 degrees; the radius of a circular arc at the bottom of the piston head is 8mm to 9mm; the cone angle of a central lug boss is 135 degrees to 145 degrees; the depth of the central lug boss is 8mm to 10mm; the radius of the transition fillet of an inclined plane and the bottom circular arc face is 2mm to 3mm; the radius of the transition fillet of a throat inlet part and a top face is 1mm to 3mm; and the radius of the transition fillet of the throat inlet part and the bottom circular arc face is 5mm to 7mm. The structure makes the best of the advantage of strengthened oil-gas mixture of the contraction end combustion chamber at the piston head, which makes oil spout delayed further and creates condition for reducing NOX. The contraction end combustion chamber at the piston head strengthens the air stream movement of late burning in a cylinder and promotes the late burning, which is favorable to soot oxidation and can reduce the discharge of the engine obviously.

Description

A kind of diesel motor piston head construction

Technical field

The utility model relates to the diesel engine piston firing chamber, relates in particular to the low emissions diesel piston firing chamber.

Background technique

At present, in the direct injection diesel engine that China produces, piston head adopts the ω firing chamber relatively extensively, the structure of this firing chamber, shape, size and the position of piston head to cylinder in air motion and oil gas is mixed that bigger influence is all arranged, thereby directly have influence on the combustion performance of diesel engine.The straight mouthful toroidal combustion chamber of the many employings in the firing chamber of diesel engine with direct injection now, when adopting retarded injection to reduce NOX, its exhaust smoke rising is very fast, and this is because this firing chamber causes the flame of bottom clearance part to mend cooling and produce a large amount of soots; Because the oral area of firing chamber is straight mouth structure, and quench area is less, therefore can not form enough crowded stream in addition, so air utilization ratio is on the low side, cause the mixed effect of fuel and air to reduce, can't form desirable inflammable mixture, it is insufficient to burn, and causes emission performance can't reach environmental requirement.At the problems referred to above, it is reducing ω firing chamber that a kind of piston combustion bowl is arranged at present, straight mouthful ω firing chamber, this firing chamber can increase the crowded stream effect of firing chamber, to improve the utilization ratio of air, but because the footpath of firing chamber is dark in less mostly, relation between balance quality and the discharging well, simultaneously boss plane, middle part is less, and the air utilization ratio in the firing chamber is on the low side.

The model utility content

At the deficiency that prior art exists, the utility model aims to provide a kind of diesel motor piston head construction.This structure makes full use of piston crown reentrant combustion chamber oil gas and mixes the characteristics of strengthening, make oil spout to postpone more, created advantage for reducing NOX, the piston crown reentrant combustion chamber has been strengthened the air motion of after burning in the cylinder, promote the carrying out of after burning, helped the oxidize soot that is generated.

The technical solution adopted in the utility model is:

A kind of diesel motor piston head construction, its piston diameter is 100-120mm, the reducing toroidal combustion chamber diameter of piston crown is 60-65mm, reentrant diameter is 50-60mm, the degree of depth is 20-25mm, the reducing angle is 40-45 °, the bottom radius of arc is 8-9mm, the central boss cone angle is 135-145 °, the central boss degree of depth is 8-10mm, the knuckle radius of inclined-plane and bottom arc surface is 2-3mm, and the aditus laryngis part is 1-3mm with end face knuckle radius, and the aditus laryngis part is 5-7mm with the knuckle radius of bottom arc surface.

Described piston diameter is 110mm, the reducing toroidal combustion chamber diameter of piston crown is 62.5mm, reentrant diameter is 56mm, and the degree of depth is 22.5mm, and the reducing angle is 42 °, the bottom radius of arc is 8.5mm, the central boss cone angle is 140 °, and the central boss degree of depth is 9mm, and the knuckle radius of inclined-plane and bottom arc surface is 2.5mm, the aditus laryngis part is 2mm with end face knuckle radius, and the aditus laryngis part is 6mm with the knuckle radius of bottom arc surface.

The calibre ratio of combustion chamber of described piston crown and footpath are dark, and the combustion recess volume is 52.09mL than being respectively 0.84 and 2.91, and dead volume is 19.901mL, and compression ratio ε equals 17.5, and capacity utilization K equals 0.724.

The utility model is by improving the piston crown structure, rationally increase the calibre ratio of combustion chamber of piston crown and footpath deeply than, increase piston crown reducing and firing chamber base frame volume simultaneously, make full use of the guide functions of base frame, form desired crowded stream and adverse current, promote oil gas to mix, motor is being changed under the minimum situation, rational Match by firing chamber and fuel injection system, can if be applied in enterprise's production, can save the R﹠D costs of enterprise greatly so that engine emission reaches state III level, promote the upgrading of heavy goods vehicles discharging, have good social benefit and economic benefit.

Description of drawings

Fig. 1 is a structural representation of the present utility model.

Embodiment

As shown in Figure 1, the diameter of piston 1 is 110mm, piston crown adopts reducing toroidal combustion chamber 2, its diameter is 62.5mm, reentrant diameter is 56mm, the degree of depth is 22.5mm, and the reducing angle is 42 °, and the bottom radius of arc is 8.5mm, the central boss cone angle is 140 °, central boss degree of depth 9mm, the knuckle R=2.5mm of inclined-plane and bottom arc surface, aditus laryngis part and end face knuckle R=2mm, the knuckle R=6mm of aditus laryngis part and bottom arc surface, increase piston crown reentrant combustion chamber base frame volume simultaneously, make full use of the guide functions of base frame, form desired crowded stream and adverse current, promote oil gas to mix, equal to increase relatively the volume of firing chamber periphery when compression ratio remains unchanged, can improve air utilization ratio, this is to improving engine power performance, Economy and emission performance have positive meaning.

The utility model is by analyzing diesel engine air inlet system, fuel injection characteristic and cylinder head general arrangement, reasonable Arrangement piston head ω combustion-chamber shape and size, rationally increase the calibre ratio of combustion chamber of piston crown and footpath deeply than, under the constant condition of firing chamber diameter, suitably increase middle part boss volume, and increase boss inclined-plane, middle part cone angle, and simultaneously by the rational Match of firing chamber and fuel injection system, can be so that engine emission reaches state III level.

The utility model is not limited to above-mentioned preferred forms, and anyone can draw other various forms of products under enlightenment of the present invention.Though but on its shape or structure, do any variation, every identical with the utility model or akin technological scheme is all within its protection domain.

Claims

1, a kind of diesel motor piston head construction, it is characterized in that, piston diameter is 100-120mm, the reducing toroidal combustion chamber diameter of piston crown is 60-65mm, reentrant diameter is 50-60mm, the degree of depth is 20-25mm, the reducing angle is 40-45 °, the bottom radius of arc is 8-9mm, the central boss cone angle is 135-145 °, and the central boss degree of depth is 8-10mm, and the knuckle radius of inclined-plane and bottom arc surface is 2-3mm, the aditus laryngis part is 1-3mm with end face knuckle radius, and the aditus laryngis part is 5-7mm with the knuckle radius of bottom arc surface.

2, diesel motor piston head construction according to claim 1, it is characterized in that, described piston diameter is 110mm, the reducing toroidal combustion chamber diameter of piston crown is 62.5mm, reentrant diameter is 56mm, the degree of depth is 22.5mm, the reducing angle is 42 °, the bottom radius of arc is 8.5mm, the central boss cone angle is 140 °, and the central boss degree of depth is 9mm, and the knuckle radius of inclined-plane and bottom arc surface is 2.5mm, the aditus laryngis part is 2mm with end face knuckle radius, and the aditus laryngis part is 6mm with the knuckle radius of bottom arc surface.

3, diesel motor piston head construction according to claim 1, it is characterized in that, the calibre ratio of combustion chamber of described piston crown and footpath are dark in being respectively 0.84 and 2.91, the combustion recess volume is 52.09mL, dead volume is 19.901mL, compression ratio ε equals 17.5, and capacity utilization K equals 0.724.