CN1115003A

CN1115003A - Piston top surface structure of multi-valve engine

Info

Publication number: CN1115003A
Application number: CN95102013A
Authority: CN
Inventors: 藤田康夫
Original assignee: YUNISIAJAX CO Ltd
Current assignee: YUNISIAJAX CO Ltd
Priority date: 1994-02-28
Filing date: 1995-02-28
Publication date: 1996-01-17
Also published as: KR950033038A; JPH07243327A

Abstract

A piston tip side structure of a multi-valve motor is provided to eliminate stay portions of unburned gas to enhance combustion efficiency. A valve escape groove 5 for suction valve 4 adjacent each other in the circumferential direction of a piston main body 1 and a valve escape groove 7 for an exhaust valve 6 are formed on the crown surface 1a of the piston main body 1, and the valve escape grooves 5, 7 are communicated through a communicating groove 8 to constitute a recess 9, which opens in a bow shape, having a circular arc 9a on the outer circumferential side of the piston main body 1. The cross section extending in the direction of the diameter of the piston main body 1, passing the center of the circular arc 9a of the recess 9 is formed in almost V shape, and the bottom of the recess is formed in the flat surface 93.

Description

The piston-top surface structure of multi-valve type motor

The present invention relates to a kind of piston-top surface structure that at least a valve of Aspirating valves or outlet valve is arranged on with partnering the multi-valve type motor (for example 4 valve type engines) on the cylinder head.

General known multi-valve type motor is that the end face by cylinder head, cylinder and piston only constitutes the firing chamber, and the vortex generation device that makes mixed gas form vortex is being set around the said cylinder center in this firing chamber.

But, even in this multi-valve type motor, also the samely with general motor, on the end face of piston only, do not conflict ground, formation of the valve head and the end face of piston only that make Aspirating valves and outlet valve distinguishes corresponding valve with Aspirating valves and outlet valve and discharges ditch.Therefore, between the circumferential a pair of Valved discharge ditch that adjoins each other of piston only, just form wall portion,, thereby the problem that makes the vortex decay is arranged because this wall portion can harm flowing of the vortex that forms in the firing chamber.

Therefore,, just above-mentioned two Valved discharge ditches are provided with communicatively, have the recess of the arcuate openings of circular arc part in the outer periphery formation of above-mentioned piston only by being communicated with ditch for above-mentioned wall portion is removed.Also proposed as Japanese patent gazette real open clear 62-82328 number disclosed scheme, in this recess, the Valved discharge ditch that Valved discharge ditch that Aspirating valves uses and outlet valve are used is set communicatively by being communicated with ditch, with be provided with communicatively by being communicated with the several valves discharging ditch that several valves discharging ditch that ditch uses Aspirating valves and outlet valve use, it is " V " font that the section configuration along the warp-wise of piston only of passing through centers of arc sections of any one recess is all formed roughly.

But, a kind of piston-top surface structure as shown in Figure 3 and Figure 4 before above-mentioned, the valve rod 4b of Aspirating valves 4 is configured to more tilt than the valve rod 6b of outlet valve 6, the valve head 4a of Aspirating valves 4 is configured on center one side than the end face 1a of the more close piston only 1 of valve head 6a of outlet valve 6.Therefore, the opening length that makes progress in the footpath of piston only 1 of recess 19 is just than the length of the recess opening in a kind of piston-top surface structure in above-mentioned back.Using the plane of inclination parallel 19 with the valve head 4a of Aspirating valves 4 ₁The plane of inclination 19 that parallels with the valve rod 4b of Aspirating valves 4 roughly ₂Constitute under the occasion of bottom of such recess 19, the recess in the degree of depth of recess 19 and a kind of piston-top surface structure in above-mentioned back compare just darker in circular arc 19a side.Because the narrow of the bags has been formed on the bottom of the circular arc part 19a side of above-mentioned recess 19, thereby when engine running, when mixed gas burns in the firing chamber, be deposited in problem in the above-mentioned narrow with regard to having unburned gas.

The present invention makes in order to solve the above problems, and its objective is provides a kind of piston-top surface of multi-valve type motor structure, and it can remove unburned gas and retain the space, improves combustion efficiency.

To achieve the above object, piston-top surface structure of the present invention be on the end face of piston only, form along this piston only circumferentially, the Valved discharge ditch used of the Valved discharge ditch used of the Aspirating valves that adjoins each other and outlet valve, by being communicated with ditch these two Valved discharge ditches are provided with communicatively, constitute the recess of the arcuate openings that has circular arc part in the outer periphery portion of piston only, it roughly is " V " font that the section configuration radially along piston only at the circular arc part center of passing through it of this recess is formed, and formation plane, the bottom surface of recess.

Piston-top surface structure of the present invention with said structure, because after the bottom surface sections of the recess that constitutes firing chamber formation plane, just the narrow of the bags that the bottom surface sections from above-mentioned recess is begun has removed, thereby when mixed gas burns, can prevent that unburned gas is deposited in the recess in the firing chamber, and the flame that is formed by the burning in the firing chamber is not rested in the recess outwards spread.

Fig. 1 (1) is the planimetric map of piston-top surface structure of the multi-valve type motor of expression embodiments of the invention;

Fig. 1 (2) is the sectional drawing of Fig. 1 (1);

Fig. 2 is the enlarged view of the major component shown in the presentation graphs 1 (2);

Fig. 3 (1) is the planimetric map of the piston-top surface structure of the multi-valve type motor before the expression;

Fig. 3 (2) is the sectional drawing of Fig. 3 (1);

Fig. 4 is the enlarged view of the major component shown in the presentation graphs 3 (2).

Below, with reference to accompanying drawing embodiments of the invention are described.

Fig. 1 (1) is the planimetric map of piston-top surface structure of the multi-valve type motor of expression embodiments of the invention, and Fig. 1 (2) is the sectional drawing of Fig. 1 (1), and Fig. 2 is the enlarged view of the major component shown in the presentation graphs 1 (2).

In these figure, the 1st, piston only, this piston only 1 is installed in 2 li in cylinder, can freely slide therein.By not having the cylinder head of expression to constitute firing chamber 3 on this piston only 1 and cylinder 2 and the figure.

On the end face 1a of the above-mentioned piston only 1 that constitutes this firing chamber 3, in the propelling side of piston only 1 and counter to advance side to form respectively a pair of at the Valved discharge ditch 5 of Aspirating valves 4 usefulness that upwards adjoin each other in the week of piston only 1 and the Valved discharge ditch 7 of outlet valve 6 usefulness.

The Valved discharge ditch 5 of above-mentioned Aspirating valves 4 usefulness and the Valved discharge ditch 7 of outlet valve 6 usefulness are provided with communicatively by being communicated with ditch 8, constitute recess 9 by this

discharging ditch

5,7 that is communicated with ditch 8 and above-mentioned two valves, the oral area of this recess 9 is arranged on the outer periphery place of piston only 1, is to have the arc of circular arc part 9a.

This recess 9 is by the plane of inclination 9 that more tilt, parallel with the valve head 4a of Aspirating valves 4 of the valve head 6a than outlet valve 6 ₁Roughly parallel plane of inclination 9 with the valve rod 4b of Aspirating valves 4 ₂The center of formation by the circular arc part 9a of recess 9, roughly become " V " font along the radially section configuration of piston only 1.

The bottom surface of above-mentioned recess 9 is by the plane parallel with the end face 1a of above-mentioned piston only 19 ₃Above-mentioned plane of inclination 9 ₁With plane of inclination 9 ₂Connecting ground constitutes.Under the prerequisite of the valve head 6a of valve head 4a that does not influence above-mentioned Aspirating valves 4 and outlet valve 6, with above-mentioned plane 9 ₃Be arranged on the end face 1a place of as close as possible piston only 1.

The present invention with said structure is owing to make the plane parallel with the end face 1a of piston only 19 to the bottom surface of the recess 9 that constitutes firing chamber 3 ₃The narrow of the firing chamber that will begin from the bottom surface of above-mentioned recess 9 has removed, thereby when mixed gas in the firing chamber during 3 internal combustion, can prevent that unburned gas is deposited in 9 li of recesses, because the flame of 3 internal combustion can not rest on recess and spreads for 9 li in the firing chamber, thereby can improve combustion efficiency.

As mentioned above, because the present invention forms the Valved discharge ditch that the Valved discharge ditch used along the Aspirating valves that upwards adjoins each other in this piston only week and outlet valve are used on the end face of piston only, by being communicated with ditch these two Valved discharge ditches are provided with communicatively, and constitute the recess of the arcuate openings that has circular arc part at the outer periphery place of above-mentioned piston only, and the centers of arc sections of passing through above-mentioned recess of recess, forming along the radially section configuration of piston only roughly is " V " font, again the bottom surface sections of recess is formed the plane, thereby having removed of the bags that just the recess bottom surface that constitutes the firing chamber is begun than narrow, when mixed gas burns in above-mentioned firing chamber, can prevent that unburned gas is deposited in the recess, combustion flame in the firing chamber is not rested in the recess to spread, so, with former comparing, combustion efficiency can be positively improved, HC (hydrocarbon) can be suppressed because of partial combustion produces.

Claims

1. the piston-top surface structure of a multi-valve type motor, it is characterized in that it be on the end face of piston only, form along this piston only circumferentially, the Valved discharge ditch used of the Valved discharge ditch used of the Aspirating valves that adjoins each other and outlet valve, by being communicated with ditch these two Valved discharge ditches are provided with communicatively, constitute the recess of the arcuate openings that has circular arc part in the outer periphery portion of piston only, roughly is forming along the radially section configuration of piston only of the centers of arc sections of passing through it of this recess " V " font, and the bottom surface sections of recess formation plane.