JP2022099878A - engine - Google Patents

Abstract

To provide an engine capable of reducing wear of a sliding part of a tappet even when the number of intake/exhaust valves is increased.SOLUTION: A rocker arm bracket 40 of an engine 1 includes an oil supply path 50. In the oil supply path 50, lubrication oil 100 supplied from a rocker arm shaft 30 is supplied to a tappet 13 and a tappet hole 14 which are sliding parts. The oil supply path 50 is formed to be inclined obliquely downwardly in order to supply oil toward the tappet 13 and the tappet hole 14 in the rocker arm bracket 40.SELECTED DRAWING: Figure 2

Description

The present invention relates to an engine such as a diesel engine.

An engine, such as a diesel engine, comprises a rocker arm shaft and a rocker arm bracket. The rocker arm bracket has a function of supporting the rocker arm shaft. The rocker arm shaft is provided with a path for supplying lubricating oil to the rocker arm bracket. Oil is supplied to the fitting gap between the rocker arm shaft and the rocker arm bracket to lubricate the components around the rocker arm bracket. Patent Document 1 discloses a structural example of a rocker arm bracket of an engine.

Some diesel engines are provided with a total of four intake / exhaust valves per cylinder. When a diesel engine is provided with a total of 4 intake / exhaust valves per cylinder, the intake / exhaust valves are operated when the intake / exhaust valves are operated as compared with a diesel engine provided with a total of 3 or less intake / exhaust valves per cylinder. , The force applied to the tappet increases. As the force applied to the tappet increases, the wear of the sliding parts of the tappet increases. Therefore, wear measures are required to suppress wear of the sliding portion of the tappet.

Japanese Unexamined Patent Publication No. 2005-264844

The present invention has been made to solve the above problems, and an object of the present invention is to provide an engine capable of reducing wear of a sliding portion of a tappet even if the number of intake / exhaust valves increases. ..

The subject is an engine including a rocker arm bracket that supports a rocker arm shaft, and the rocker arm bracket is an oil that supplies lubricating oil supplied from the rocker arm shaft to a sliding portion of a tappet. The present invention has a supply path, and the oil supply path is formed so as to be inclined diagonally downward in order to supply the oil toward the sliding portion of the tappet in the rocker arm bracket. It is solved by the engine related to.

According to the engine according to the present invention, the rocker arm bracket has an oil supply path for supplying lubricating oil supplied from the rocker arm shaft to the sliding portion of the tappet. The oil supply path is formed in the rocker arm bracket so as to be inclined diagonally downward toward the sliding portion of the tappet. Therefore, the lubricating oil is smoothly supplied to the sliding portion of the tappet through the oil supply path inclined diagonally downward. As a result, even if the number of intake / exhaust valves increases and the force applied to the tappet increases, the wear of the sliding portion of the tappet can be reduced.

In the engine according to the present invention, the sliding portion of the tappet is preferably characterized by including the tappet and a tappet hole for sliding the tappet.
According to the engine according to the present invention, wear between the tappet hole and the tappet included in the sliding portion of the tappet can be reduced.

In the engine according to the present invention, the oil supply path is preferably a through hole provided in the rocker arm bracket and a notch formed so as to connect to the through hole supporting the rocker arm shaft. It is characterized by that.
According to the engine according to the present invention, an oil supply path can be easily obtained at low cost only by forming a notch portion diagonally downward in the rocker arm bracket.

In the engine according to the present invention, preferably, the rocker arm bracket is formed in a region between the oil supply path and the tappet hole through which the oil passes, and the surface area is increased to hold the oil. It is characterized by having a holding region portion.
According to the engine according to the present invention, the rocker arm bracket has an oil holding region portion formed in a region through which oil passes between the oil supply path and the tappet hole. The oil holding region portion is a portion where the surface area is increased to hold the oil. Therefore, the surface area of the oil holding region portion for adhering and holding the oil can be easily increased. Therefore, when the engine repeats start and stop, oil can be supplied to the tappet hole and the tappet from the oil holding region even if the engine is stopped. Therefore, it is possible to reduce the supply shortage of oil to the tappet hole and the tappet.

In the engine according to the present invention, the oil holding region portion is preferably formed on the wall surface of the rocker arm bracket located above the tappet hole.
According to the engine according to the present invention, the oil holding region portion of the wall surface of the rocker arm bracket can increase the surface area for adhering and holding oil. Therefore, when the engine repeats start and stop, oil can be supplied to the tappet hole and the tappet from the oil holding region even if the engine is stopped. Therefore, it is possible to reduce the supply shortage of oil to the tappet hole and the tappet.

In the engine according to the present invention, the oil holding region portion is preferably a region in which the surface area is increased by arranging a plurality of protrusion portions.
According to the engine according to the present invention, the surface area for adhering and holding oil can be easily increased at low cost by simply arranging a plurality of protrusions in the oil holding region portion.

According to the present invention, it is possible to provide an engine capable of reducing wear of the sliding portion of the tappet even if the number of intake / exhaust valves is increased.

It is a figure which shows the diesel engine as an example of the engine which concerns on embodiment of this invention. It is a figure which shows the structure of the region R of the engine shown in FIG. 1 in an enlarged manner. It is a front view which shows the rocker arm bracket. It is a perspective view which shows the rocker arm bracket. It is a figure which shows the rocker arm bracket of the 2nd Embodiment of this invention. FIG. 5 is an enlarged view showing the structure of the region R of the engine having the rocker arm bracket of FIG.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
Since the embodiments described below are suitable specific examples of the present invention, various technically preferable limitations are added, but the scope of the present invention is particularly limited to the present invention in the following description. Unless otherwise stated, the present invention is not limited to these aspects. Further, in each drawing, the same components are designated by the same reference numerals, and detailed description thereof will be omitted as appropriate.

(First Embodiment)
<Configuration example of engine 1>
FIG. 1 shows a diesel engine as an example of the engine according to the embodiment of the present invention. The engine 1 shown in FIG. 1 is, for example, a common rail type diesel engine, and the engine 1 is, for example, an industrial diesel engine. The engine 1 is, for example, a supercharged high-output 4-cylinder engine with a turbocharge. The engine 1 is mounted on equipment for various purposes such as construction machinery, agricultural machinery, and lawn mowers.

In the engine 1 shown in FIG. 1, the hatching showing the cross section is omitted for the sake of simplification of the drawing. The engine 1 is, for example, a multi-cylinder overhead valve type diesel engine, which is a four-valve direct injection type diesel engine having two intake valves and two exhaust valves. The engine 1 includes a cylinder block 2, a cylinder head 3, and a head cover 4, and the lower portion of the cylinder block 2 and the oil pan are not shown.

The head cover 4 is assembled on the cylinder head 3 and houses a rocker arm bracket 40, a rocker arm shaft 30, and the like. The cylinder block 2 has an upper cylinder 5 and a lower crankcase 6. The piston 8 is arranged in the cylinder 5. The crankshaft 9 is arranged in the crankcase 6. The piston 8 is connected to the crank shaft 9 via a connecting rod 10.

The cylinder 5 has a valve cam chamber 11. The valve drive cam shaft 12 and the cam 12C are housed in the valve drive cam chamber 11. The tappet 13 can move up and down along the tappet hole 14. The tappet 13 and the tappet hole 14 correspond to a sliding portion of the tappet. The lower part of the tappet 13 is mounted on the cam 12C of the valve drive camshaft 12. The push rod 15 passes through the push rod insertion hole 16. The rocker arm 17 is arranged in the head cover 4. The hemispherical upper end support portion 15T of the push rod 15 receives and supports the hemispherical lower end receiving portion 17R on the one end side of the rocker arm 17. The rotation of the cam 12C of the valve camshaft 12 causes the tappet 13 to move up and down in the tappet hole 14, and the push rod 15 to move up and down in the push rod insertion hole 16 to receive the lower end of the rocker arm 17. The unit 17R is moved up and down.

The rocker arm 17 is fixed to the rocker arm shaft 30, and the rocker arm 17 can swing around the rocker arm shaft 30. The other end of the rocker arm 17 is connected to the intake rocker bridge 31. The intake rocker bridge 31 is fixed to the boss 32. The intake rocker bridge 31 fixes the upper ends of the intake valves 33, 33. The springs 34 and 34 are arranged between the cylinder head 3 and the intake rocker bridge 31.

In the state shown in FIG. 1, the intake valves 33 and 33 are pushed up by the urging force of the springs 34 and 34, and the intake valves 33 and 33 close the intake ports 35 and 35. When the valve drive camshaft 12 and the cam 12C rotate, the push rod 15 is pushed up. When the push rod 15 is pushed up, the pushed up force of the push rod 15 is transmitted to the rocker arm 17, and the rocker arm 17 moves around the rocker arm shaft 30. As a result, the two intake valves 33 and 33 are pushed down by the rocker arm 17 against the urging force of the springs 34 and 34, so that the intake valves 33 and 33 open the intake ports 35 and 35, respectively. There is. The above-mentioned structural example is an opening / closing operation mechanism by moving the intake valves 33 and 33 up and down, but two exhaust valve opening / closing operation mechanisms (not shown) also have a similar structure. In FIG. 1, the rocker arm bracket 40 is on the rear side of the rocker arm 17.
In FIG. 1, the axial direction of the crank shaft 9 of the engine 1 is the X direction, the width direction of the engine 1 is the Y direction, and the vertical direction of the engine 1 is the Z direction.

As an example, the lubricating oil (lubricating oil) in the head cover 4 shown in FIG. 1 falls to the oil pan side (not shown) in the following oil return path. The oil return path has a push rod insertion hole 16, an inside of the tappet 13, an oil outflow hole 21, an valve cam chamber 11, and an oil drop hole 22. The oil outflow hole 21 is provided in the tappet 13. The oil drop hole 22 is provided from the valve cam chamber 11 to the crankcase 6. As a result, the lubricating oil in the head cover 4 is in the push rod insertion hole 16, the inside of the tappet 13, the oil outflow hole 21, the valve cam chamber 11, the oil drop hole 22, and the crankcase 6. It can be returned to the oil pan through. Although not shown, each of the four cylinders of the cylinder head 3 is connected to an intake passage and an exhaust passage.

FIG. 2 shows an enlarged structure of the region R of the engine 1 shown in FIG.
As shown in FIG. 2, the rocker arm shaft 30 is rotatably supported by the rocker arm bracket 40. The rocker arm bracket 40 is fixed to the cylinder head 3. Structural examples of the rocker arm bracket 40 are shown in FIGS. 3 and 4. FIG. 3 is a front view showing the rocker arm bracket 40, and FIG. 4 is a perspective view showing the rocker arm bracket 40.

<Rocker arm bracket 40>
As shown in FIGS. 3 and 4, the rocker arm bracket 40 has a through hole 41 having a circular cross section and an oil supply path 50 having a notch shape. The rocker arm shaft 30 shown in FIG. 2 is supported by the through hole 41 shown in FIGS. 3 and 4. Although not shown, the rocker arm shaft 30 has, for example, an oil guide passage for guiding lubricating oil along the axial direction. The oil supply path 50 is continuously formed in the through hole 41, and the oil supply path 50 is formed so as to extend along the radial direction of the through hole 41. The oil supply path 50 is a notch formed in the through hole 41 for supporting the rocker arm shaft 30. Moreover, the oil supply path 50 is formed so as to extend diagonally downward from the through hole 41.

As shown in FIG. 3, the oil supply path 50 shown in FIGS. 2 to 4 is formed so as to be tilted diagonally downward by a predetermined angle θ with respect to the Y direction in the YZ plane. The angle θ is such that the lubricating oil 100 in the head cover 4 shown in FIG. 2 passes from the oil guide passage of the rocker arm shaft 30 to the inner peripheral surface of the push rod 15 and the push rod insertion hole 16 via the oil supply path 50. The value of the angle that can be smoothly supplied into the tappet 13 and the tappet hole 14 shown in FIG. 1 without any delay due to gravity is not particularly limited.

As described above, as shown in FIGS. 3 and 4, the oil supply path 50 is formed so as to be inclined diagonally downward by a predetermined angle θ, so that the tip portion 51 of the oil supply path 50 is a push rod 15. It faces the upper end support portion 15T and reaches a position close to the upper end support portion 15T.

As a result, the lubricating oil 100 flows from the upper end support portion 15T of the push rod 15 along the push rod 15, the inner peripheral surface of the push rod insertion hole 16, and the inner peripheral surface of the tappet 13 and the tappet hole 14. Can be smoothly supplied to. Therefore, it is possible to reduce the wear of the outer peripheral surface of the tappet 13 and the inner peripheral surface of the tappet hole 14. That is, due to the smooth and reliable supply of the oil 100, the inner peripheral surface of the push rod insertion hole 16 is wetted by the oil, the lubricity on the outer peripheral surface of the tappet 13 and the inner peripheral surface of the tappet hole 14 is improved, and the outer peripheral surface of the tappet 13 is improved. The wear resistance of the surface and the inner peripheral surface of the tappet hole 14 can be improved, and the life of the engine 1 shown in FIG. 1 can be extended.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. 5 and 6.
FIG. 5 shows the rocker arm bracket 40A of the second embodiment of the present invention, and FIG. 6 shows an enlarged structure of the region R of the engine. The elements of the rocker arm bracket 40A of the second embodiment shown in FIGS. 5 and 6 have the same reference numerals as the elements of the rocker arm bracket 40 of the first embodiment shown in FIGS. 2 and 3. The explanation is omitted.

The rocker arm bracket 40A shown in FIGS. 5 and 6 differs from the rocker arm bracket 40 shown in FIGS. 2 and 3 as follows. An oil holding region portion 60 is formed on the surface of the rocker arm bracket 40A. The oil holding region portion 60 is a region through which the oil 100 passes between the tip portion 51 of the oil supply path 50 and the push rod insertion hole 16, and is formed on the wall surface 40S of the rocker arm bracket 40A.

The oil holding region portion 60 is a portion where the surface area is increased in order to temporarily hold the oil 100 on the wall surface 40S. For example, as shown in FIGS. 5 and 6, the oil holding region portion 60 is formed on the wall surface 40S of the rocker arm bracket 40A. The oil holding region portion 60 increases the surface area of the wall surface 40S by arranging a plurality of protrusions 61 in a predetermined arrangement pattern on the YZ plane in order to temporarily hold the oil 100. The protrusions 61 can be arranged, for example, in a staggered pattern on the wall surface 40S. The shape of the protrusion 61 is a semicircular shape in the illustrated example, but the shape is not limited to this, and various shapes such as a triangular pyramid shape and a triangular prism shape can be adopted.

The lubricating oil 100 flows from the upper end support portion 15T of the push rod 15 along the push rod 15 (see FIG. 2), and as shown in FIG. 6, along each protrusion 61 of the oil holding region portion 60. Also flows. Therefore, the amount of the oil 100 due to the surface adhesion of the oil 100 in the oil holding region 60 increases.

As described above, on the surface of the rocker arm bracket 40A, the amount of the oil 100 due to the surface adhesion of the oil 100 in the oil holding region portion 60 can be increased. Therefore, for example, when the engine 1 shown in FIG. 1 is stopped, the oil 100 held in the oil holding region portion 60 can be supplied to the outer peripheral surface of the tappet 13 and the inner peripheral surface of the tappet hole 14. When the engine 1 repeatedly starts and stops, even if the engine 1 is stopped, the oil 100 for lubrication can be supplied from the oil holding region portion 60 to the tappet hole and the tappet. Therefore, it is possible to reduce the supply shortage of the oil 100 to the outer peripheral surface of the tappet 13 and the inner peripheral surface of the tappet hole 14.

Therefore, for example, in a device that repeatedly starts and stops, the lubricity of the inner peripheral surface of the push rod insertion hole 16 of the engine, the outer peripheral surface of the tappet 13 and the inner peripheral surface of the tappet hole 14 is improved, and the outer peripheral surface of the tappet 13 is improved. Wear between the surface and the inner peripheral surface of the tappet hole 14 can be reduced. That is, the smooth and reliable supply of the oil 100 improves the lubricity on the inner peripheral surface of the tappet hole 14 and improves the wear resistance, so that the life of the engine 1 shown in FIG. 1 can be extended.

As described above, in the engine 1 of the embodiment of the present invention, it is possible to reduce the wear of the inner peripheral surface of the tappet hole 14 which is the sliding portion of the tappet and the outer peripheral surface of the tappet 13. The oil supply path 50 can be easily obtained at low cost only by forming a notch in the rocker arm brackets 40 and 40A in the diagonally downward direction. In the rocker arm bracket 40A, an oil holding region portion 60 is formed in a region between the tip portion 51 of the oil supply path 50 and the push rod insertion hole 16 through which the oil 100 passes. Therefore, the oil holding region portion 60 can easily increase the surface area to which the oil 100 is attached and temporarily held (reserved).

The oil holding region portion 60 of the wall surface 40S of the rocker arm bracket 40A can increase the surface area for temporarily holding (storing) the oil 100 by adhering it. Therefore, when the engine 1 repeats starting and stopping, the oil 100 can be supplied from the oil holding region portion 60 to the tappet hole 14 and the tappet 13 even if the engine is stopped, so that the oil 100 to the tappet hole 14 and the tappet 13 can be supplied. It is possible to reduce the supply shortage. Only by arranging 60, for example, a plurality of protrusions 61 in the oil holding region portion, the surface area for holding the oil in the plurality of protrusions 61 can be easily increased at low cost.

The embodiment of the present invention has been described above. However, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of claims. The configuration of the above embodiment may be partially omitted or may be arbitrarily combined so as to be different from the above.
In the illustrated example, for example, a 4-cylinder industrial diesel engine is taken as an example of the engine, but the engine of the present invention is not limited to this, and can be applied to a gasoline engine, a hybrid engine, or the like, and is large to small. Applicable to the engine of.

In the example shown in FIGS. 5 and 6, the oil holding region portion 60 is configured by arranging a plurality of protrusions 61, but the present invention is not limited to this, and for example, the oil holding region portion 60 has a plurality of recesses. It may be configured by arranging it, or it may be configured by combining a plurality of protrusions and a plurality of recesses. Further, the shape of the protrusions and recesses of the oil holding region 60 may be point-like or linear as shown in FIGS. 5 and 6.

1: Engine, 2: Cylinder block, 3: Cylinder head, 4: Head cover, 5: Cylinder, 6: Crank case, 8: Piston, 9: Crank shaft, 10: Conrod, 11: Valve cam chamber, 12: Dynamic Valve camshaft, 12C: cam, 13: tappet, 14: tappet hole, 15: push rod, 15T: upper end support, 16: push rod insertion hole, 17: rocker arm, 17R: lower end receiving part, 21: oil outflow Hole, 22: Oil drop hole, 30: Rocker arm shaft, 31: Intake rocker bridge, 32: Boss, 33: Intake valve, 34: Spring, 35: Intake port, 40: Rocker arm bracket, 40A: Rocker arm bracket, 40S: wall surface, 41: through hole, 50: oil supply path, 51: tip, 60: oil holding area, 61: protrusion, 100: oil, R: area

Claims (6)

An engine with a rocker arm bracket that supports the rocker arm shaft.
The rocker arm bracket has an oil supply path for supplying lubricating oil supplied from the rocker arm shaft to the sliding portion of the tappet.
The engine is characterized in that the oil supply path is formed so as to be inclined diagonally downward in order to supply the oil toward the sliding portion of the tappet in the rocker arm bracket. The engine according to claim 1, wherein the sliding portion of the tappet includes the tappet and a tappet hole for sliding the tappet. The second aspect of the present invention, wherein the oil supply path is a through hole provided in the rocker arm bracket and is a notch formed so as to be connected to the through hole supporting the rocker arm shaft. Engine. The rocker arm bracket is characterized by having an oil holding region portion formed in a region between the oil supply path and the tappet hole through which the oil passes and having an increased surface area for holding the oil. The engine according to claim 2 or 3. The engine according to claim 4, wherein the oil holding region portion is formed on a wall surface of the rocker arm bracket located above the tappet hole. The engine according to claim 4 or 5, wherein the oil holding region portion is a region in which the surface area is increased by arranging a plurality of protrusions.

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