JP3003661B2 - V-type engine for automobiles mounted horizontally on a crankshaft - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a V-type engine for a horizontally mounted crankshaft automobile, in which a camshaft for driving an intake valve and a camshaft for driving an exhaust valve are provided in each cylinder row. In particular, the present invention relates to a transmission for driving a valve train such as a cam shaft for driving an intake valve or a cam shaft for driving an exhaust valve, and an engine cooling device. 2. Description of the Related Art Conventionally, a V-type engine provided with a cam shaft for driving an intake valve and a cam shaft for driving an exhaust valve for each cylinder row is disclosed, for example, in Japanese Utility Model Laid-Open No. 57-176604. Something was done. The valve train of this V-type engine has two valve drive camshafts provided in each cylinder row.
It has a structure in which it is connected to a crankshaft via a timing chain, and a timing chain is provided for each cylinder row. [0003] However, the conventional V thus constructed is
In the type engine, a sprocket having an outer diameter approximately twice as large as a sprocket for a timing chain of a crankshaft is attached to two valve driving camshafts of each cylinder row. Sprockets must be separated from each other so that they do not touch each other. For this reason, there was a limit in reducing the size of the cylinder head. The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to reduce the size of a cylinder head, open and close timing of each intake valve, and exhaust gas. It is an object of the present invention to provide a V-type engine for an automobile having a crankshaft mounted laterally, in which the opening / closing timing of the valve is less liable to occur and the engine cooling efficiency can be improved. [0005] In order to achieve the above-mentioned object, a V-type engine for a crankshaft-mounted automobile according to the present invention has a radiator arranged in front of the engine, and is provided for each cylinder row. Two camshafts, an inner intake valve driving camshaft and an outer exhaust valve driving camshaft, are provided, and only the intake valve driving camshaft and the crankshaft of each cylinder row are connected to a single endless transmission band. Power is transmitted by the intake valve at the front of the engine
Strain the endless drive belt between the drive camshaft and the crankshaft.
-The camshaft and clutch for driving the intake valve at the rear of the engine
The endless transmission band between the shafts is connected to the endless transmission band by a first transmission means in which a tension pulley abuts, and the single endless transmission band is covered with an inverted triangular cover. Two camshafts, a driving camshaft and an exhaust valve driving camshaft, are connected by a second transmission means to which power is transmitted by an endless transmission band, and a cam sprocket pulley for an endless transmission band of the second transmission means. The diameter of the shaft is smaller than that of the endless transmission belt cam sprocket pulley of the first transmission means, and an intake pipe is provided above the inside of the V-type engine and an exhaust pipe is provided outside the V-type cylinder block. . Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of an engine room of an automobile. An engine 3 and a transmission 4 are mounted by auxiliary frames 5 inside left and right wheel walls 2, 2. 6 is a radiator installed in front of the engine room
Reference numeral 7 denotes an electric cooling fan. The engine 3 is a V-type six-cylinder engine in which a crankshaft 8 is arranged horizontally in the left-right direction of the vehicle, and a row of cylinders is arranged before and after the crankshaft. That is, as shown in FIG. 2, the front and rear cylinder rows each have a combustion chamber 14 formed by the cylinder 10, the cylinder head 12, and the piston 13, and each combustion chamber 14 is provided with two intake valves 15. Thus, two intake passages 16 are connected to two exhaust passages 18 via two exhaust valves 17. Reference numeral 19 denotes an intake valve driving cam shaft for driving the intake valve 15, reference numeral 20 denotes an exhaust valve driving cam shaft for driving the exhaust valve 17, and the intake valve driving cam shaft 19 is arranged in a V-shape. The exhaust valve driving camshaft 20 is arranged inside the cylinders 10, 10, and the exhaust valve driving camshaft 20 is arranged outside. In the intake passage 16, two pipes having different lengths are provided inside a V-type engine for one combustion chamber. Reference numerals 21 and 21 denote intake distribution boxes which form upstream ends of the intake passages 16 and are mounted on the upper portions of the cylinder heads 12 of the respective cylinder rows. One of the two intake passages 16 has a short pipe just above it. One long pipe is connected to the intake distribution box 21 of the cylinder row on the other side.
They are connected at 6 'and 16'. Reference numeral 22 denotes an exhaust pipe forming a part of the exhaust passage 18, which is located outside the V-shaped cylinder block and extends downward from each cylinder row. Exhaust pipe 22 of front cylinder row
Extends rearward from the rear of the radiator 6 via an exhaust purification catalyst 24 disposed on the lower surface of the crankcase 23, and the exhaust pipe 22 of the rear cylinder row is connected to an exhaust purification catalyst 25 disposed behind the crankcase 23. , And after being merged, they are opened to the atmosphere via an exhaust silencer (not shown). Next, the structure of a device for driving the intake valve driving cam shaft 19 and the exhaust valve driving cam shaft 20 will be described. Two camshafts 19 for driving the intake valves disposed inside the V bank protrude outward from one side of the cylinder head 12, and a first driven pulley 19a, which is a cam sprocket pulley for an endless transmission band, is fixed thereto. ing. The first driven pulley 19a is a toothed first pulley forming a part of the first transmission means.
The first belt attached to the crankshaft 8 via the timing belt 26
It is driven by the driving pulley 8a. 27 is a tension pulley that tensions the first timing belt 26, and 28 is the first timing belt.
3 is an inverted triangular belt cover for covering the belt 26 . Soshi
As shown in FIG. 4, the driving of accessories necessary for the engine
Is a bell separate from the other pulleys attached to the cran shaft 8.
It is what is done in each. The first transmission means according to the present invention comprises a first driven pulley 1 mounted on each intake valve driving cam shaft 19,19.
9a, a first drive pulley 8a of the crankshaft 8, the first drive pulley 8a and the first driven pulleys 19a, 19a.
And a single endless transmission belt or the like as a single endless power transmission belt. And FIG.
As shown in the figure, a camshaft 19a for driving the intake valve at the front of the engine.
The endless drive belt between the shaft and the crankshaft 8 is formed in a straight line.
The camshaft 19a for driving the intake valve at the rear of the engine is
A tension pulley 27 abuts on the endless transmission belt between the link shafts 8
Have been. From the other side of the cylinder head 12, a cam shaft 19 for driving the intake valve and a cam shaft 20 for driving the exhaust valve protrude to the outside. The second drive pulley 19b which is a pulley
A second driven pulley 20a, which is a cam sprocket pulley for an endless transmission band, is fixed to the camshaft 20 for driving the exhaust valve. Both pulleys are connected to a second timing belt 29 of an endless transmission band which forms a part of the second transmission means.
Are connected to each other. 30 is a belt cover,
31 is a tension pull. The second transmission means according to the present invention comprises a second drive pulley 19b mounted on the intake valve drive cam shaft 19 on the side opposite to the first driven pulley 19a, and an exhaust valve drive camshaft 19. Second driven pulley 20a attached to camshaft 20
And a second timing belt 29 of an endless power transmission belt wound around these pulleys. And the second
The second drive pulley 19b and the second driven pulley 20a of the transmission means are formed to have the same diameter as each other, and have a smaller diameter than the first driven pulley 19a of the first transmission means. In the V-type engine configured as described above,
The rotation of the crankshaft 8 is transmitted to two intake valve driving camshafts 19 arranged inside the V bank by one first timing belt 26 and first driven pulley 19a. Two intake valve driving camshafts 19 and two exhaust valve driving camshafts 2
0 means that the second drive pull 19b and the second driven pulley 2 are located on the other side of the engine (on the side opposite to the first transmission means).
Oa and the second timing belt 29 of the endless power transmission belt wound around them rotate while maintaining a specific phase. As described above, the camshaft 19 for driving the intake valve and the camshaft 20 for driving the exhaust valve of each cylinder row rotate in conjunction with the rotation of the crankshaft 8. Therefore, the second drive pulley 19b and the second driven pulley 2 of the second transmission means coupled to the intake valve drive camshaft 19 and the exhaust valve drive camshaft 20 are provided.
0a is the camshaft 19 for driving the intake valve in the first transmission means.
By making the diameter smaller than that of the first driven pulley 19a, the outer dimensions of the entire second transmission means can be reduced. By bringing the camshaft 19 for driving the intake valve closer to the camshaft 20 for driving the exhaust valve, the interval between the two camshafts can be reduced, so that the cylinder head 12 can be downsized. The cover 28 of the first transmission means is formed in an inverted triangular shape so as to cover a single endless transmission band connecting only the intake valve driving camshaft and the crankshaft of each cylinder row. That fits compactly on the side of the engine and has a gap in the engine room.
It is easy to make and there is no front slope of the inverted triangular cover 28
It can be formed in a straight line along the end drive belt and along the slope.
Running wind Te may turn easily flow to the lower and rear engine. [0017] Then, the cylinder head 12 is compact, the better a Rukoto distribution around the engine running wind,
Radiator - motor 6 and radiator - cooling the front and rear of the exhaust pipe 22 between the motor 6 and the cylinder block is performed efficiently, the cooling efficiency of the cooling water is improved both the exhaust pipe 22
Also it is prevented and the intake efficiency deterioration Ru is improved. The V-type engine for a horizontally mounted crankshaft automobile according to the present invention has two cams, one for the inner intake valve driving camshaft and the other for the outer exhaust valve driving camshaft, for each cylinder row. the shaft is provided, wherein only the intake valve drive cam shaft and the crankshaft of each cylinder bank, power is transmitted by a single endless transmission belt 且
Between the camshaft for driving the intake valve at the front of the engine and the crankshaft.
The endless drive belt is formed as a straight line,
The endless drive band between the camshaft for driving the valve and the crankshaft is tight.
The tension pulleys are connected by the first transmission means in contact therewith, and the single endless transmission band is covered with an inverted triangular cover, and the camshaft for driving the intake valve and the driving valve for driving the exhaust valve of each of the cylinder rows. The two camshafts of the camshafts are connected by a second transmission means to which power is transmitted by an endless transmission band, and the endless transmission cam sprocket pulley of the second transmission means is connected to the endless transmission band of the first transmission means. The diameter of the belt is smaller than that of the belt cam sprocket pulley.
The outer dimensions of the transmission means are reduced, and the interval between the two cam shafts can be reduced by bringing the intake valve driving cam shaft closer to the exhaust valve driving cam shaft, thus reducing the size of the cylinder head. be able to. Also, the cover of the first transmission means is compactly housed on the side of the V-type engine , so that a gap is easily formed in the engine room, and an inverted triangular shape is formed.
The front slope of the cover also forms a straight line along the endless transmission band.
The wind generated along the slope can be generated at the bottom and rear of the engine.
It is easy to flow and the flow of the running wind around the engine is improved. Then, the cylinder head is downsized,
Radiation is improved because the flow of wind around the engine is improved.
Front and between the radiator and the cylinder block
The cooling of the exhaust pipe on the rear and rear
And the exhaust pipe is prevented from deteriorating.
The intake efficiency is also improved, resulting in an excellent V-type engine for automobiles with a horizontal crankshaft. The first transmission means and the second transmission means may have
There is a slight difference in expansion and contraction in each endless drive belt in
Also, each intake valve drive cam shaft and exhaust valve drive cam shaft
First or second transmission means between the respective intake valve driving cam shafts
The camshaft for driving the intake valve and the camshaft for driving the exhaust valve rotate simultaneously
The opening and closing intervals of similar valves
And the opening / closing phase difference between different valves in both banks
And the intake and exhaust valves perform the desired opening and closing operations.
It is a V-type engine for automobiles that is surely executed and has excellent crankshaft lateral placement.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of an engine room of an automobile equipped with an automobile V-type engine according to the present invention. FIG. 2 is a side view in which a part of the engine compartment of FIG. 1 is cut away. FIG. 3 is a cutaway side view of the engine compartment of FIG. 1; FIG. 4 is an arrangement diagram showing an arrangement of belts. FIG. 5 is a sectional view taken along line VV in FIG. 4; [Description of Signs] 3 Engine 6 Radiator 8 Crankshaft 8a First drive pulley 16 'Intake pipe 19 Camshaft 19a for driving intake valve First driven pulley (cam sprocket pulley) 19b Second drive Pulley (cam sprocket pulley) 20 Exhaust valve driving camshaft 20a Second driven pulley (cam sprocket pulley) 22 Exhaust pipe 26 First timing belt (endless transmission belt) 27 Tension pulley 28 Cover 29 Second timing belt (Endless drive belt)

   ────────────────────────────────────────────────── ─── Continuation of front page       (56) References JP-A-59-70820 (JP, A)                 Shokai Sho 57-185627 (JP, U)                 Japanese Utility Model Showa 58-9554 (JP, U)                 CAR GRAPHIC. 18 [7               (Showa 54-7-1) 98−100

Claims (1)

(57) [Claims] 1.2 In a V-type engine for a crankshaft-mounted automobile having a V-shaped arrangement of cylinder rows, a radiator is arranged in front of the engine and an inner side is provided for each cylinder row. The two camshafts of the intake valve driving camshaft and the outer exhaust valve driving camshaft are provided, and only the intake valve driving camshaft and the crankshaft of each of the cylinder rows are connected by a single endless transmission band. power is transmitted 且
Between the camshaft for driving the intake valve at the front of the engine and the crankshaft.
The endless drive belt is formed as a straight line,
The endless drive band between the camshaft for driving the valve and the crankshaft is tight.
The tension pulleys are connected by the first transmission means in contact with each other, and the single endless transmission band is covered with an inverted triangular cover, and the camshaft for driving the intake valve and the driving valve for driving the exhaust valve of each of the cylinder rows. The two camshafts of the camshafts are connected by a second transmission means to which power is transmitted by an endless transmission band. A V-type engine for a horizontally mounted crankshaft, characterized in that the diameter of the V-type engine is smaller than that of the belt cam sprocket pulley, and an intake pipe is provided above the inside of the V-type engine and an exhaust pipe is provided outside the V-type cylinder block.