CN101131131A

CN101131131A - General overhead type petrol engine cylinder head

Info

Publication number: CN101131131A
Application number: CNA2007100927506A
Authority: CN
Inventors: 杨光固
Original assignee: Lifan Industry Group Co Ltd
Current assignee: Lifan Technology Group Co Ltd
Priority date: 2007-09-25
Filing date: 2007-09-25
Publication date: 2008-02-27

Abstract

The general in-head cylinder head for gasoline engine has one axially contracted combustion chamber to form two squishing planes symmetrical about the cylinder axis, and one spark plug with altered inclination angle and thus in the position near the center of the combustion chamber. The present invention is favorable to the combustion of mixed gas and to raised torque and power of the engine. At the same time, the irregular combustion chamber comprising circular arc cambers has changeable radius and adjustable compression ratio.

Description

General overhead type petrol engine cylinder head

Technical field

The present invention relates to a kind of engine cylinder head, specifically, in particular for the cylinder head of general overhead type petrol engine motor.

Background technique

The shape of engine cylinder head firing chamber is to the combustion process important influence, the bowl-in-piston chamber of circular flat bottom is often adopted in the general gasoline engines firing chamber at present, as shown in Figure 1, this firing chamber has and is arranged on the piston crown end face and towards the bowl-type groove of combustion chamber openings, oil nozzle injects fuel in this bowl-type groove, jet is by groove deflection, the central authorities that the directive firing chamber is relative with spark plug, the air-flow and the disturbance atomizing that have simultaneously been improved through described bowl-type groove in the firing chamber are fine fuel droplet, and/or be vaporized, and with the air mixing that sucks the firing chamber.Bowl-in-piston chamber has compact structure, flame travel is short, crowded stream is stronger, the advantage that compression ratio is big, but because the reasons in structure of overhead type cylinder head, spark-plug location can not design the center portion in the firing chamber, thereby caused the skew of spark plug, be unfavorable for burning in ignition position, firing chamber; In addition, because the firing chamber height adjustment range is limited, so the scope of the volume adjustment of firing chamber is limited equally, does not satisfy different compression ratio designing requirement.

Summary of the invention

The object of the present invention is to provide a kind of general overhead type petrol engine cylinder head, solve of the skew of overhead type petrol engine spark plug, cause to be unfavorable for the problem of burning in ignition position, firing chamber.

For achieving the above object, technological scheme of the present invention is as follows: a kind of general overhead type petrol engine cylinder head, the bowl-in-piston chamber that comprises the cylinder head bottom, and the intake duct that runs through chamber wall, air outlet flue and spark plug adapter, described firing chamber has flat-top and around the side, should be around the side by be connected and extend to the arcuate surface formation of cylinder head lower end surface with the flat-top tangent line, inwardly shrink along cylinder axis away from a side of spark plug adapter described firing chamber, forming two is left squish face and the right squish face that the symmetrical line symmetry distributes with the cylinder axis, like this, original circular chamber is close away from a side direction spark plug of spark plug adapter, help making center, firing chamber deflection to spark plug, thereby reach the purpose of ignition at the center, firing chamber; In order to make the end gas minimizing of being heated, described spark plug adapter is near a side of intake duct, and on the basis of above-mentioned change combustion-chamber shape, in order to make ignition location as far as possible near the center, firing chamber, spark plug adapter is further centroclinal to the firing chamber, the angle of the shaft axis of spark plug adapter and cylinder head lower end surface is 76～78 degree, with the angle of yaw of cylinder axis be 20～22 degree, design also has the another one benefit like this, and promptly spark plug adapter helps the dismounting and the installation of spark plug at described angle tilt in level and Vertical direction.

Around making the firing chamber, form smooth curved side, help the jet reflection, and for the ease of regulating combustion chamber volume, the intersection line of above-mentioned left squish face and right squish face is a camber line, this camber line has 8～13 millimeters radius, except the side at two described circular arc places, described side has 3～8 millimeters radius.In order to make central electrode outstanding, the oral area reaming of described spark plug adapter, this reaming part surface is a cambered surface.

Set forth comparing beneficial effect of the present invention below in conjunction with motor after improving and the stand test that improves preceding motor:

Table 1: improve front engine stand test test result

Sequence number	Speed of crankshaft r/min	Power measurer rotating speed r/min	Measure moment of torsion Nm	Measure power kW	Standard state moment of torsion Nm	Standard state power kW	Fuel consumption Kg/h	Fuel consumption rate g/kWh
Sequence number	Speed of crankshaft r/min	Power measurer rotating speed r/min	Measure moment of torsion Nm	Measure power kW	Standard state moment of torsion Nm	Standard state power kW	Fuel consumption Kg/h	Fuel consumption rate g/kWh	1	3808	3808	2.94	1.17	3.08	1.24	0.45	379
2	3612	3612	2.79	1.05	2.97	1.11	0.45	422	1	3808	3808	2.94	1.17	3.08	1.24	0.45	379
2	3612	3612	2.79	1.05	2.97	1.11	0.45	422	3	3407	3407	2.64	0.94	2.76	1.00	0.43	445
4	3307	3307	2.60	0.90	2.76	0.96	0.41	447	3	3407	3407	2.64	0.94	2.76	1.00	0.43	445
4	3307	3307	2.60	0.90	2.76	0.96	0.41	447	5	3202	3202	2.53	0.85	2.65	0.90	0.39	447
6	3103	3103	2.42	0.79	2.55	0.84	0.38	477	5	3202	3202	2.53	0.85	2.65	0.90	0.39	447

(continuing)

7	3006	3006	2.30	0.73	2.44	0.77	0.78	1048
7	3006	3006	2.30	0.73	2.44	0.77	0.78	1048	8	2904	2904	2.02	0.61	2.12	0.65	0.37	591
9	2805	2805	2.11	0.62	2.23	0.66	0.33	530	8	2904	2904	2.02	0.61	2.12	0.65	0.37	591

Table 2: improve rear engine stand test test result

Sequence number	Speed of crankshaft r/min	Power measurer rotating speed r/min	Measure moment of torsion Nm	Measure power kW	Standard state moment of torsion Nm	Standard state power kW	Fuel consumption Kg/h	Fuel consumption rate g/kWh
Sequence number	Speed of crankshaft r/min	Power measurer rotating speed r/min	Measure moment of torsion Nm	Measure power kW	Standard state moment of torsion Nm	Standard state power kW	Fuel consumption Kg/h	Fuel consumption rate g/kWh	1	3807	3807	3.73	1.49	3.96	1.60	0.85	571
2	3602	3602	3.85	1.45	4.18	1.55	0.82	563	1	3807	3807	3.73	1.49	3.96	1.60	0.85	571
2	3602	3602	3.85	1.45	4.18	1.55	0.82	563	3	3409	3409	3.82	1.37	4.07	1.47	0.80	583
4	3203	3203	3.76	1.26	4.07	1.35	0.74	586	3	3409	3409	3.82	1.37	4.07	1.47	0.80	583
4	3203	3203	3.76	1.26	4.07	1.35	0.74	586	5	3004	3004	3.80	1.20	4.07	1.29	0.71	594
6	2804	2804	3.80	1.12	4.07	1.20	0.70	629	5	3004	3004	3.80	1.20	4.07	1.29	0.71	594
6	2804	2804	3.80	1.12	4.07	1.20	0.70	629	7	2604	2604	3.78	1.03	4.07	1.10	0.61	596
8	2398	2398	3.62	0.91	3.86	0.97	0.57	631	7	2604	2604	3.78	1.03	4.07	1.10	0.61	596
8	2398	2398	3.62	0.91	3.86	0.97	0.57	631	9	2202	2202	3.60	0.83	3.86	0.89	0.52	630

By above-mentioned table 1, table 2 as can be seen, when speed of crankshaft is the 3600r/min left and right sides, the standard state moment of torsion and the standard state power of the motor after the improvement are respectively 4.18Nm and 1.55kW, and the motor before improving then is 2.97Nm and 1.11kW, has obviously improved the moment of torsion and the power of motor; When speed of crankshaft was the 3000r/min left and right sides, the standard state moment of torsion and the standard state power of the motor after the improvement were respectively 4.07Nm and 1.29kW, and the motor before improving only is 2.44Nm and 0.77kW, has obviously improved the moment of torsion and the power of motor.

Can draw from top analysis, because the present invention is modified into erose firing chamber with the bowl-in-piston chamber of original circular flat bottom, and the angle of inclination that changes spark plug, reached the purpose at the as far as possible close center, firing chamber, position that makes spark plug, help combustion of mixed gas, thereby the moment of torsion and the power of motor have been improved, and, this irregular shape firing chamber is made up of the circular arc camber of different radii, can adjust compression ratio by changing radius, therefore, the compression ratio adjustment of motor realizes easily.

Description of drawings

Fig. 1 is the combustion-chamber shape schematic representation before improving;

Fig. 2 is shape (facing) schematic representation of firing chamber of the present invention;

Fig. 3 be along T-T among Fig. 2 to view;

Fig. 4 be along B-B among Fig. 2 to view;

Fig. 5 is the zoomed-in view of firing chamber 5 among Fig. 2

Fig. 6 is the rear view of Fig. 2;

Fig. 7 be along R-R among Fig. 4 to view.

Embodiment

Further the present invention is illustrated below in conjunction with drawings and Examples:

As Fig. 2, Fig. 3, Fig. 4 and shown in Figure 5, main points of the present invention be bowl-in-piston chamber with original circular flat bottom along cylinder axis to inside contraction, forming two is left squish face 6 and the right squish face 7 that the symmetrical line symmetry distributes with the cylinder axis, in the present embodiment, the external frame of described left squish face 6 and right squish face 7 is by straightway and the circular arc formation of joining, and, left circular arc 6a one end at squish face 6 places, a left side and the right circular arc 7a at right squish face 7 places join, the left straightway 6b of the other end and this left side squish face 6 joins, equally, right circular arc 7a one end at right squish face 7 places and the left circular arc 6a at left squish face 6 places join, the right straightway 7b of the other end and this right side squish face 7 joins, and described left circular arc 6a and right circular arc 7a have 12 millimeters radius; The intersection line of described left squish face 6 and right squish face 7 is a camber line 8, and this camber line 8 has 15 millimeters radius, and except the side at two described left circular arc 6a and right circular arc 7a place, described side 5b has 3～8 millimeters radius.

Further as Fig. 2, Figure 6 and Figure 7, described spark plug adapter 2 is near a side of intake ducts 3, and the angle of the shaft axis of spark plug adapter 2 and cylinder head lower end surface L is 77 degree, is 21 to spend with the angle of yaw of cylinder axis, the oral area reaming of spark plug adapter 2, this reaming part surface is a cambered surface.

Claims

1. general overhead type petrol engine cylinder head, the bowl-in-piston chamber (5) that comprises cylinder head (1) bottom, and the intake duct (3) that runs through chamber wall, air outlet flue (4) and spark plug adapter (2), described firing chamber (5) has flat-top (5a) and around side (5b), should be around the side by be connected and extend to the arcuate surface formation of cylinder head (1) lower end surface (L) with flat-top (5a) tangent line, described spark plug adapter (2) is near a side of intake duct (3), it is characterized in that: inwardly shrink along cylinder axis away from a side of spark plug adapter (2) described firing chamber (5), and forming two is left squish face (6) and the right squish face (6 ') that the symmetrical line symmetry distributes with the cylinder axis; The angle of the shaft axis of described spark plug adapter (2) and cylinder head lower end surface (L) is 76～78 degree, with the angle of yaw of cylinder axis be 20～22 degree.

2. general overhead type petrol engine cylinder head according to claim 1, it is characterized in that: the external frame of described left squish face (6) and right squish face (7) is by straightway and the circular arc formation of joining, and, left circular arc (6a) end at squish face (6) place, a left side and the right circular arc (7a) at right squish face (7) place join, the left straightway (6b) of the other end and this left side squish face (6) joins, and described circular arc has 10～12 millimeters radius.

3. general overhead type petrol engine cylinder head according to claim 1 and 2 is characterized in that: the intersection line of described left squish face (6) and right squish face (7) is camber line (8), and this camber line (8) has 8～13 millimeters radius; Except the side at two described left circular arcs (6a) and right circular arc (7a) place, described side (5b) has 3～8 millimeters radius.

4. general overhead type petrol engine cylinder head according to claim 1 is characterized in that: the oral area reaming of described spark plug adapter (2), this reaming part surface is a cambered surface.