JP2001342843A - Horizontal internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce height of the horizontal internal combustion engine, to lighten and compact the engine, and to sufficiently keep vertical weight and dimension balance for a crankshaft. SOLUTION: This horizontal internal combustion engine comprises substantially horizontally disposed crankshaft 5 and cylinder part 3. A cam shaft 40 is disposed over the crankshaft 5, and a fuel injection pump 51 operated by the cam shaft 40 is disposed in a cylinder block 1 part over the cylinder part 3. A balancer shaft 28 is disposed at a position lower than the crankshaft 5 and oppositely of the cylinder disposition side with respect to the crankshaft 5, and drives a lubricating oil pump 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a horizontal internal combustion engine in which a crankshaft and a cylinder are both arranged substantially horizontally.

[0002]

2. Description of the Related Art FIGS. 3 and 4 show a conventional example of a single-cylinder horizontal internal combustion engine of this type. In FIG. 3 showing a longitudinal section, a cylinder portion 101 and a crankshaft 102 of a cylinder block 100 are both in a horizontal posture. The camshaft 103 is disposed below the crankshaft 102, and the balancer shaft 105 is located on the opposite side of the crankshaft 102 from the cylinder portion disposed side and slightly above the crankshaft 102. Are located. The camshaft 103 has a camshaft gear 1 that meshes with a camshaft drive gear 110 of the crankshaft 102.
11 and a valve operating cam 106 for driving the intake and exhaust valves. A poppet rod 107 is engaged with the valve operating cam 106, and a push rod 108 connected to the poppet rod 107 passes under the cylinder part 101 and the cylinder head 120 to form a valve arm cover 121.
And is in contact with the intake and exhaust valve arms 122.

The lubricating oil pump 115 is disposed near the lubricating oil level L1 so as to be as close as possible to the lower oil pan 123 of the cylinder block 100, and the pump / governor weight driving gear 112 is connected to the camshaft gear 111.
Are engaged.

In FIG. 4 showing a horizontal cross section of FIG. 3, the fuel injection pump 114 is disposed on the side of the cylinder portion 101 in the direction of the crankshaft center O 1, and is mounted on the side opening of the cylinder block 100. It is mounted on the lid 116. A pump driving tappet 114 a of the fuel injection pump 114 is engaged with a pump cam 103 formed on the cam shaft 103.

A flywheel case 131 is fixed to the side opposite to the side on which the side lid 116 is disposed, and the flywheel 13
0 is stored.

[0006]

As shown in FIG. 3, a horizontal internal combustion engine in which the cylinder portion 101 and the crankshaft 102 are arranged horizontally has a lower overall engine height than a vertical internal combustion engine in which cylinders are arranged vertically. can do. However, since the camshaft 103 is disposed below the crankshaft 102 and the fuel injection pump 114 is disposed on the side of the cylinder 101, the following problem occurs.

(1) When the camshaft 103 is disposed below the crankshaft 102, the lubricating oil surface L1 and the crankshaft are connected to prevent the lower end of the camshaft gear 111 from immersing in the lubricating oil surface L1. 102 and at least the camshaft gear 111
, A vertical interval corresponding to the diameter of the cylinder block must be secured, and the crankshaft height H01 from the cylinder block lower end surface 100a increases. In particular, since the camshaft 103 rotates at half the rotation speed of the crankshaft 102, the camshaft gear 111 is the same as the camshaft driving gear 110 of the crankshaft 102.
The size of the camshaft gear 111 also contributes to the increase in the crankshaft height H01.

When the camshaft 103 is disposed below the crankshaft 102, the crankshaft O is located in the cylinder block 100 above the crankshaft 102.
The height (width in the vertical direction) H02 from 1 can be kept small. However, the flywheel case 13 projects above the upper end of the cylinder block 100,
The height H03 of the whole engine will inevitably increase.

If the position of the camshaft gear 111 is to be lowered, a gear cover or the like must be separately provided to prevent the camshaft gear 111 from being immersed in the lubricating oil in the oil pan 123. It's complicated.

(2) As shown in FIG. 3, the crankshaft height H01
, The center of gravity of the entire cylinder block is increased.

(3) As shown in FIG. 4, the fuel injection pump 114
Is disposed on the side of the cylinder portion 101 in the direction of the crankshaft center O1, the size of the cylinder block 100 in the direction of the crankshaft center increases, and the weight also increases.

(4) When the position of the camshaft 103 is low, for example, when the camshaft PTO is used, a pulley or the like attached to the PTO shaft portion of the camshaft 103 is eclipsed downward from the lower end surface (attachment surface) of the cylinder block. Protrude.

[0013]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an invention according to claim 1 of the present application is directed to a horizontal internal combustion engine in which a crankshaft and a cylinder portion are both arranged substantially horizontally, and a cam is provided above the crankshaft. A horizontal internal combustion engine, wherein a shaft is disposed, and a fuel injection pump operated by a cam shaft is disposed in a cylinder block portion above a cylinder portion.

According to a second aspect of the present invention, there is provided the horizontal internal combustion engine according to the first aspect, wherein the balancer shaft is disposed at a position lower than the crankshaft on a side opposite to the cylinder portion arrangement side with respect to the crankshaft. The lubricating oil pump is driven by the shaft.

[0015]

1 and 2 show a single-cylinder horizontal diesel engine to which the present invention is applied. In FIG. 2 showing a horizontal sectional view, FIG. 2 shows a cylinder block 1 in which a cylinder liner 2 is fitted. The cylinder part 3 and the crankshaft 5 are horizontally arranged, integrally having a part 3 and a crankcase part 6 in which the crankshaft 5 is housed. A cylinder head and a valve arm cover 11 are sequentially fastened to the end surface of the cylinder portion 3 in the direction of the cylinder center line C1.

One end of the crankcase 6 in the direction of the crankshaft O1 is open, and a side cover 8 is fixed to the opening, and the flywheel 13 is housed in the other end of the crankcase 6 in the direction of the crankshaft O1. A flywheel case (fan case) 14 is fixedly mounted. Here, for ease of explanation, it is assumed that the direction of the cylinder center line C1 is the front-rear direction, the direction of the crankshaft center O1 is the left-right direction, the cylinder head 10 side is the front side, and the side lid 8 side is the left side. This will be described below.

The left end of the crankshaft 5 is supported by the side cover 8 and protrudes leftward, and the protruding portion serves as an output shaft 18. The right end of the crankshaft 5 is supported by the right end wall of the crankcase 6. At the same time, the flywheel 13 protrudes into the flywheel case 14, and the flywheel 13 is fixed to the protruding end. A cooling fan 15 is formed on the flywheel 13.

The crank shaft 5 is provided with a crank pin 21 via a pair of left and right crank arms 20 and connected to a piston 23 via a connecting rod 22. A cam is provided between the side cover 8 and the left crank arm 20. Shaft drive gear 2
The balancer driving gear 26 is fixed between the right crank arm 20 and the right end wall of the crankcase part 6.

The balancer drive gear 26 meshes with a balancer gear 29 of a balancer shaft 28 disposed below and below the crankshaft 5. The right end of the balancer shaft 28 is supported by the right end wall of the crankcase 6, and the left end is supported by the side cover 8. The side cover 8 has a lubricating oil pump 30 on the same axis as the balancer shaft. The pump shaft 31 of the lubricating oil pump 30 is connected to the balancer shaft 28 via an Oldham coupling mechanism.

In the cylinder head 10, a pair of intake and exhaust valves 33 are arranged on the left and right sides of the cylinder center line C1.

FIG. 1 is a longitudinal sectional view, and a circle shown by a virtual line indicates an outer periphery of the flywheel case 14. The valve arm cover 11 is fastened to the upper half of the cylinder head 10,
The fuel injection valve 34 is mounted below the cylinder center line C1. A pair of left and right suction and exhaust valve arms 35 are swingably disposed in the valve arm cover 3, and the lower ends of the suction and exhaust valve arms 35 contact the front ends of the suction and exhaust valves 33, respectively. The upper end of the valve arm 35 is connected to the cylinder 3 and the cylinder head 1.
It is in contact with the front end of the push rod 38 arranged above the zero.

In the crankcase 6, a camshaft 40 is disposed above the crankshaft 5, and a governor weight shaft 41 is disposed behind the camshaft 40. As described above, the balancer shaft 28 It is arranged behind the crankshaft 5 and below the crankshaft 5. The camshaft 40 is formed with a valve operating system cam 43 for driving intake and exhaust valves, a pump cam 44 for driving a fuel injection pump, and a camshaft gear 45.
Reference numeral 5 meshes with the camshaft drive gear 25 of the crankshaft 5. The drive gear 47 of the governor weight shaft 41 is engaged with the camshaft gear 45.

A pump mounting hole 50 is formed in the upper wall of the crankcase portion 6 above the cylinder portion 3 at a position corresponding to the front upper direction of the camshaft 40.
At 0, the fuel injection pump 51 is inserted and fixed in a forwardly inclined position, and the tappet 52 for driving the fuel injection pump 50 is in contact with the pump cam 44 of the cam shaft 40. Also,
A vertical regulator shaft 54 is disposed at a front upper portion of the governor weight shaft 41 and is supported by an upper wall of the crankcase portion 6. A governor lever 57 is provided at a lower end of the regulator shaft 54 and an upper end Is provided with a regulator lever 56. One end of the governor lever 57 is connected to a governor mechanism, and the other end is connected to a fuel control lever of the fuel injection pump 51.

Rod insertion holes 60 and 61 are formed in the upper portions of the cylinder portion 3 and the cylinder head 10, respectively. The push rods 38 for driving the suction and exhaust valves are disposed in the rod insertion holes 60 and 61, respectively. The rear end of the push rod rod 38 is in contact with the valve operating cam 43 of the cam shaft 40 via the poppet rod 62.

An oil pan 7 is integrally formed at the lower end of the crankcase 6, and lubricating oil is stored in the oil pan 7 up to an oil level L1.
9 and the balancer shaft 28 are arranged such that their lower ends are located slightly above the oil level L1.

[0026]

In FIG. 2, the rotation of the crankshaft 5 is directly output to the outside by the output shaft 18, but is also transmitted to the balancer shaft 28 via the balancer driving gear 26 and the balancer gear 29, and further from the balancer shaft 28. Lubricating oil pump 3
It is also transmitted to 0.

In FIG. 1, the rotation of the crankshaft 5 is transmitted through the camshaft drive gear 25 and the camshaft gear 45 to the camshaft 4.
0, and further to the governor weight shaft 41 via the governor drive gear 45.

The rotation of the cam shaft 40 causes the pump cam 4
The fuel injection pump 51 is driven via the tappet 4 and the tappet 52, and the intake / exhaust valve 33 is opened / closed via the valve train cam 43, the poppet rod 62, the push rod 38 and the intake / exhaust valve arm 35.

In the structure shown in FIGS. 1 and 2, the camshaft 40 is disposed above the crankshaft 5 so that the height H1 from the lower end surface 1a of the cylinder block 1 to the crankshaft center O1 is reduced. The crankshaft center O1 is located substantially at the center of the vertical width (H1 + H2) of the cylinder block 1. Thereby, the cylinder block 1
A vertical dimension H2 of a portion above the crankshaft center O1,
The dimension (crankshaft height) H1 of the lower portion of the crankshaft core O1 can be made substantially the same, and the cylinder block 1 can be housed in a well-balanced manner in the center of the flywheel case 14 in the up-down direction. Further, the height (total engine height) H3 from the lower end surface 1a of the cylinder block to the upper end of the flywheel case can be significantly reduced as compared with FIG.

Further, by disposing the balancer shaft 28 behind and below the crankshaft 5, the upper and lower weight distribution with respect to the crankshaft core O1 is achieved in combination with the uniformity of the vertical dimensions H1 and H2 with respect to the crankshaft core O1. Can also be kept in good balance.

[0031]

Other Embodiments of the Invention (1) It is also possible to apply the present invention to a multi-cylinder horizontal internal combustion engine.

[0032]

(1) According to the first aspect of the present invention, by disposing the camshaft 40 above the crankshaft 5, the height H1 of the crankshaft can be suppressed and the crankshaft O1 can be reduced. , The upper and lower dimensions H1, H2 can be made substantially uniform, and the cylinder block 1 fits well in the center of the overall engine height H3 in a well-balanced manner.
Can be kept low. Thus, an internal combustion engine suitable for a working machine mounted on the underfloor can be provided.

(2) Camshaft 40 and Fuel Injection Pump 51
Is arranged above the crankshaft 5 and the cylinder portion 3 and the balancer shaft 28 is arranged below the crankshaft 5, so that the vertical dimension H with respect to the crankshaft core O1 is increased.
1. In addition to the uniformity of H2, the weight distribution to the crankshaft center O1 can be maintained in a well-balanced manner.

(2) Position of the fuel injection pump 51 is
The cylinder block 1 is mounted not on the side of the cylinder block 1 but above the crankshaft 5 and on the cylinder block 1.
The width in one direction can be reduced and the weight can be reduced.

(3) If the balancer shaft 28 is disposed below the crankshaft 5 and the lubricating oil pump 30 is driven by the balancer shaft 29, as in the second aspect of the present invention, the lubricating oil pump 30 The power transmission mechanism for the lubricating oil pump 30 is simplified, and the number of parts can be reduced, while arranging the power supply near the oil pan.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a horizontal diesel engine to which the present invention is applied.

FIG. 2 is a horizontal sectional view of FIG.

FIG. 3 is a longitudinal sectional view of a conventional example.

FIG. 4 is a horizontal sectional view of FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder block 3 Cylinder part 5 Crankshaft 6 Crankcase part 7 Oil pan part 8 Side cover 10 Cylinder head 11 Valve arm cover 13 Flywheel 14 Flywheel case 25 Camshaft drive gear 26 Balancer drive gear 28 Balancer shaft 29 Balancer gear 30 Lubrication Oil pump 31 pump shaft 34 fuel injection valve 40 camshaft 51 fuel injection pump

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3G013 AA00 AA01 AB00 BB04 BB31 3G016 AA02 AA05 AA19 BA21 BA27 BA30 BB11 CA42 CA44 CA59 GA01 3G024 AA38 AA60 BA29 DA02 DA16 DA17 DA20 DA26 EA00 FA00

Claims (2)

[Claims] In a horizontal internal combustion engine in which a crankshaft and a cylinder are both arranged substantially horizontally, a camshaft is arranged above the crankshaft, and a fuel injection pump operated by the camshaft is arranged above the cylinder. A horizontal internal combustion engine, which is disposed in a cylinder block portion. 2. The horizontal internal combustion engine according to claim 1, wherein
A horizontal internal combustion engine wherein a balancer shaft is disposed at a position lower than the crankshaft on a side opposite to a cylinder portion disposed side with respect to the crankshaft, and the lubricating oil pump is driven by the balancer shaft.