CN203009065U

CN203009065U - Gasoline direct injection engine piston

Info

Publication number: CN203009065U
Application number: CN 201220747501
Authority: CN
Inventors: 戴基卉; 蒋继科; 罗为; 杨江; 欧云辉
Original assignee: Chongqing Changan Automobile Co Ltd
Current assignee: Chongqing Changan Automobile Co Ltd
Priority date: 2012-12-29
Filing date: 2012-12-29
Publication date: 2013-06-19
Anticipated expiration: 2022-12-29

Abstract

The utility model discloses a gasoline direct injection engine piston. The gasoline direct injection engine piston is composed of a piston top part, a piston head part and a piston skirt part, wherein the piston top part is provided with an air inlet door hole, a valve exhaust door hole, a concave hole and a bulge, the piston head part is provided with a firepower bank, and the piston skirt part is provided with two piston pin holes; and the top surface of the firepower bank is composed of two first flat surfaces, two downward sunk second flat surfaces and four circular arc transition curved surfaces connecting the first flat surfaces and the second flat surfaces. The piston can lighten the weight of the piston head part, increases the clearance volume of the firepower bank and an air cavity, and improves fuel economy.

Description

A kind of direct-injection gasoline engine piston

Technical field

The utility model relates to a kind of part of automobile engine, is specifically related to a kind of straight spray gasoline engine piston.

Background technique

Piston is the key components and parts in crank-connecting rod mechanism for engine, and its Main Function is the gas pressure that bears in cylinder, and power is passed to connecting rod by wrist pin, to promote crankshaft rotating.In piston, the effect of the firepower bank of its head is extremely important, and the excessive height of firepower bank easily causes piston heavier, is unfavorable for light-weight design; Too small first ring excess Temperature, the piston ring relaxation, bonding of easily causing of the height of firepower bank.

along with high efficiency, the needs of low oil consumption engine development, the in-cylinder direct injection technology is widely used, directly jetting gasoline engine is because pressure of explosion is higher, the heat load that the firepower bank need bear and impact are larger, the structure shape of piston head firing chamber is more complicated, and existing direct-injection gasoline engine piston is (referring to Fig. 3, Fig. 4) by piston head, piston crown and piston skirt form, piston head has two intake valves and cheats 2, two exhaust valves cheat 3, pit 4 and projection 5, piston crown has firepower bank 6, the piston skirt has two piston pin holes 7, the end face of firepower bank 6 is the plane of high unity, the weight of piston crown is heavier, clearance volume between firepower bank and cylinder is less, combustion efficiency is lower.

Summary of the invention

The purpose of this utility model is to provide a kind of direct-injection gasoline engine piston, to alleviate piston crown weight, increases the clearance volume between firepower bank and cylinder.

Direct-injection gasoline engine piston described in the utility model is comprised of piston head, piston crown and piston skirt, and piston head has intake valve hole, exhaust valve hole, pit and projection, and piston crown has the firepower bank, and the piston skirt has two piston pin holes; The end face of described firepower bank by two the first planes, two to the second plane of lower recess and connect the first plane and four arc transition curved surfaces on the second plane consist of, this arc transition curved surface and the second plane are tangent, two the first planes lay respectively at the outside, intake valve hole and the outside, exhaust valve hole, cheat to be connected by the rounding mode with exhaust valve with intake valve and be connected, two the second planes lay respectively at directly over two piston pin holes, are connected by the rounding mode with projection.The motion of intake valve can be dodged in the intake valve hole, prevents that piston head and intake valve from bumping against, and exhaust valve is cheated the motion that can dodge exhaust valve, prevents that piston head and exhaust valve from bumping against.

Further, the height difference on described the first plane and the second plane is 2mm～3mm, and the angle of the first two ends, plane and the piston line of centres is 60 °～80 °, and the angle of the second two ends, plane and the piston line of centres is 80 °～100 °.

Further, the radius of curvature of described arc transition curved surface is 5mm～10mm, and the angle of its two ends and the piston line of centres is 10 °～20 °.

The utility model firepower bank end face that existing height is consistent changes the first plane with height difference into and to the second plane of lower recess, and connect by the arc transition curved surface, thereby reduced on the whole the height of firepower bank, alleviated the weight of piston crown, increased the clearance volume between firepower bank and cylinder, make gas compression ratio and piston head combustion-chamber shape be easier to optimize, thereby improved the fuel consumption and emission index of directly jetting gasoline engine.

Description of drawings

Fig. 1 is plan view of the present utility model

Fig. 2 is the plan view of Fig. 1.

Fig. 3 is the plan view of existing direct-injection gasoline engine piston.

Fig. 4 is the plan view of Fig. 3.

Embodiment

The utility model is described in further detail below in conjunction with accompanying drawing.

embodiment 1: as Fig. 1, direct-injection gasoline engine piston shown in Figure 2, by piston head, piston crown and piston skirt form, piston head has two intake valves and cheats 2, two exhaust valves cheat 3, pit 4 and projection 5, piston crown has firepower bank 6, the piston skirt has two piston pin holes 7, exhaust valves hole, 2 and two, two intake valves hole 3 be opened in the piston head surface by periphery and with the advancing of petrol engine, the position that exhaust valve is corresponding, projection 5 is arranged on intake valve hole 2 and exhaust valve is cheated between 3, and form with the edge in intake valve hole 2 and exhaust valve hole 3 and seamlessly transit, pit 4 is opened in protruding 5 tops and cheats 2 one sides near intake valve, and form with the edge in projection 5 and intake valve hole 2 and seamlessly transit, the end face of firepower bank 6 is by two the first planes 61, two to the second plane 62 of lower recess and four the arc transition curved surfaces 63 that connect the first plane 61 and the second plane 62 consist of, the first plane 61 to the second high 2.5mm in plane 62, arc transition curved surface 63 and the second plane 62 are tangent, two the first planes 61 lay respectively at intake valve 2 outsides, hole and 3 outsides, exhaust valve hole, cheat 2 with intake valve, are connected with pit and connect by the rounding mode in exhaust valve hole 3, the angle of the first 61 two ends, plane and the piston line of centres is 70 °, two the second planes 62 lay respectively at two piston pin holes 7 directly over, be connected by the fillet 1 that has with projection 5, the angle of the second 62 two ends, plane and the piston line of centres is 80 °, four arc transition curved surfaces 63 lay respectively at two intake valves and cheat 2, two exhaust valves hole 3 apart from firepower bank edge the most nearby, its radius of curvature is 7mm, the angle of its two ends and the piston line of centres is 15 °.

Embodiment 2: the structure of direct-injection gasoline engine piston is substantially identical with embodiment 1, difference is the first plane 61 to the second high 2mm in plane 62, the angle of the first 61 two ends, plane and the piston line of centres is 60 °, the angle of the second 62 two ends, plane and the piston line of centres is 100 °, the radius of curvature of arc transition curved surface 63 is 5mm, and the angle of its two ends and the piston line of centres is 10 °.

Embodiment 3: the structure of direct-injection gasoline engine piston is substantially identical with embodiment 1, difference is the first plane 61 to the second high 3mm in plane 62, the angle of the first 61 two ends, plane and the piston line of centres is 80 °, the angle of the second 62 two ends, plane and the piston line of centres is 80 °, the radius of curvature of arc transition curved surface 63 is 10mm, and the angle of its two ends and the piston line of centres is 10 °.

Claims

1. direct-injection gasoline engine piston, formed by piston head, piston crown and piston skirt, piston head has intake valve hole (2), exhaust valve hole (3), pit (4) and projection (5), and piston crown has firepower bank (6), and the piston skirt has two piston pin holes (7); It is characterized in that: the end face of described firepower bank by two the first planes (61), two to second plane (62) of lower recess and connect the first plane and four arc transition curved surfaces (63) on the second plane consist of, this arc transition curved surface and the second plane are tangent, two the first planes lay respectively at the outside, intake valve hole and the outside, exhaust valve hole, cheat to be connected by the rounding mode with exhaust valve with intake valve and be connected, two the second planes lay respectively at directly over two piston pin holes, are connected by the rounding mode with projection.

2. direct-injection gasoline engine piston according to claim 1, it is characterized in that: described the first plane (61) is 2mm～3mm with the height difference on the second plane (62), the angle of the first two ends, plane and the piston line of centres is 60 °～80 °, and the angle of the second two ends, plane and the piston line of centres is 80 °～100 °.

3. direct-injection gasoline engine piston according to claim 1 and 2, it is characterized in that: the radius of curvature of described arc transition curved surface (63) is 5mm～10mm, the angle of its two ends and the piston line of centres is 10 °～20 °.