JPH0614417U - Blow-by gas recirculation system for engines - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] Preventing the interference of blow-by gas and oil by increasing the number of processings with the minimum reduction without increasing the size and weight of the engine and the number of parts. Provided is a blow-by gas recirculation device for an engine, which solves problems such as an abnormal increase in the internal pressure of the crankcase and an accompanying increase in the amount of oil consumption, and can shorten the oil supply time when oil is supplied from above the cylinder head. A blow-by gas recirculation device for an engine, wherein at least one blow-by gas inflow hole 21 is opened at a position slightly above a position where a tappet of a hollow push rod 20 is disposed, and an upper surface of a cylinder head 4 is provided. At least one blow-by gas outlet 22 communicating with the inflow hole 21 through the hollow portion 23 is opened at a position slightly above the upper end and slightly below the upper end.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a blow-by gas returning device for an engine, particularly an overhead valve type engine.

[0002]

[Prior art]

 In a conventional engine, particularly in an overhead valve engine 1 as shown in FIGS. 2 and 3, blow-by gas G generated in a crankcase 2 has push rod insertion holes 5 and 6 penetrating a cylinder body 3 and a cylinder head 4. The blow-by gas recirculation pipe 9 which is gathered in the head cover 7 through the gap and connects the inside of the head cover 7 and an appropriate portion of the intake pipe 8 system is recirculated into the intake pipe 8. In the figure, 10 is a push rod, 11 is a tappet fitted to the lower end of the push rod 10, 12 is a cam shaft, 13 is a rocker arm attached to a rocker shaft 13a, 13b is an adjusting screw, 14 is intake air or An exhaust on-off valve, 15 is a piston, 16 is a connecting rod, 17 is a crankshaft, 18 is an exhaust manifold, and 19 is an oil pan.

[0003]

[Problems to be solved by the device]

 In the blow-by gas recirculation system for an engine configured as described above, the oil L dropped on the upper surface of the cylinder head 4 after lubricating the valve operating mechanism such as the rocker arm 13 also passes through the gaps such as the push rod insertion holes 5 and 6 and the oil L. As it flows down into the pan 19, ascending blow-by gas G (shown by the white arrow) interferes with oil L (shown by the black arrow) that flows down, as shown in FIG. The blow-by gas G is not smoothly recirculated, the internal pressure of the crankcase 2 is abnormally increased, and there is a problem that the oil consumption rises and the oil consumption becomes excessive. Further, in order to shorten the oil supply time, a large amount of oil may be supplied from above the cylinder head 4 by removing the head cover 7. However, due to the interference between the blow-by gas G and the oil L as described above, the oil supply time may be reduced. There was a problem that could not be shortened. In order to solve such a problem, a blow-by gas passage and an oil passage are provided independently on both sides of an engine cylinder bore, which is disclosed in Japanese Utility Model Laid-Open No. 60-105810. However, the size and weight of the engine and the number of parts also increased, and the number of engine machining operations and machining time also increased significantly. The present invention was devised in order to overcome the above-mentioned drawbacks of the prior art. The blow-by is achieved without increasing the size and weight of the engine and the number of parts, and only by increasing the number of processes with the minimum reduction. Prevents interference between gas and oil to eliminate problems such as an abnormal rise in the internal pressure of the crankcase and the accompanying excessive oil consumption, and shortens the oil supply time when oil is supplied from above the cylinder head. It is an object of the present invention to provide a blow-by gas recirculation device for an engine.

[0004]

[Means for Solving the Problems]

 In order to achieve the above object, the blow-by gas recirculation device for an engine of the present invention has at least one blow-by gas inflow hole opened at a position slightly above a position where a tappet of a hollow push rod is disposed, and a cylinder. It is characterized in that at least one blow-by gas outlet communicating with the above-mentioned inflow hole through a hollow portion is opened above the upper surface of the head and slightly below the upper end. is there.

[0005]

[Work]

 The blow-by gas recirculation device for an engine of the present invention having the above structure is as follows. Even when the upward flow of the blow-by gas G 2 generated in the crankcase 2 is not blocked by the oil L flowing down from the upper surface of the cylinder head 4 during the operation of the engine 1, the push rod 20 is pushed through the inflow hole 21 of the push rod 20. Into the head cover 7 through the hollow portion 23, the hollow portion 23, the hollow portion 23, the hollow portion 23, the hollow portion 23, the hollow portion 23, and the hollow portion 23. Therefore, the interference between the blow-by gas G and the oil L flowing down is avoided, problems such as an abnormal increase in the internal pressure of the crankcase 2 and the accompanying excessive oil consumption due to oil rise are eliminated, and the upper part of the cylinder head 4 is prevented. It is possible to shorten the refueling time when refueling oil from.

[0006]

【Example】

 An embodiment of the blow-by gas recirculation system for an engine of the present invention will be described below with reference to FIG. The same devices and parts as those in the conventional example shown in FIGS. 2 and 3 are designated by the same reference numerals. Reference numeral 20 denotes a hollow push rod which opens at least one blow-by gas inflow hole 21 at a position slightly above the position where the tappet 11 is disposed, and is above the upper surface of the cylinder head 4 and which is located at the rocker arm 13 At least one blow-by gas outlet 22 is opened so as to communicate with the inlet 21 and the hollow portion 23 at a position slightly lower than the upper end in contact with the adjusting screw 13b. When the push rod 20 configured as described above is set in the overhead valve type engine 1 as shown in FIG. 2 as shown in FIG. 1, the operation is as follows. It is rotatably supported on the vehicle body B by the brackets 24, 24 spaced apart from each other. Even when the upward flow of the blow-by gas G generated in the crankcase 2 is not blocked by the oil L flowing down from the upper surface of the cylinder head 4 during the operation of the engine 1, the push rod 20 is pushed through the inflow hole 21 of the push rod 20. Into the hollow portion 23, the hollow portion 23, the hollow portion 23, the hollow portion 23, the hollow portion 23, and the outlet 22 to the head cover 7. Therefore, the interference between the blow-by gas G and the oil L flowing down is avoided, problems such as an abnormal increase in the internal pressure of the crankcase 2 and the accompanying excessive oil consumption due to oil rise are eliminated, and the upper part of the cylinder head 4 is prevented. It is possible to shorten the refueling time when refueling oil from. Further, since only the inflow hole 21 and the outflow hole 22 are formed in the hollow push rod 20, an increase in the size and weight of the engine and an increase in the number of parts can be avoided, and the number of machining of the engine, A significant increase in processing time is also prevented. Although the shape and the number of the inflow holes 21 and the outflow holes 22 are not limited in the above embodiment, they may be formed in an appropriate shape as long as the strength of the push rod 20 is not impaired, and a plurality of them may be formed. It may be provided.

[0007]

[Effect of device]

 As described above, the blow-by gas recirculation system for an engine of the present invention has at least one blow-by gas inflow hole opened at a position slightly above the position where the tappet of the hollow push rod is disposed, and the upper surface of the cylinder head. Since at least one blow-by gas outlet communicating with the inflow hole through the hollow portion is opened at a position slightly above the upper end and slightly below the upper end, the size of the engine is increased. While avoiding an increase in weight, an increase in the number of parts, a large number of engine processes, and a significant increase in processing time, the blow-by gas and the flowing oil are prevented from interfering with each other, and the crankcase internal pressure increases abnormally and In addition to eliminating problems such as excessive oil consumption due to climbing, it is possible to shorten the refueling time when refueling oil from above the cylinder head. There is an effect.

[Brief description of drawings]

FIG. 1 is an enlarged longitudinal sectional view of an essential part showing an embodiment of a blow-by gas recirculation system for an engine of the present invention,

FIG. 2 is a partially cutaway front view showing a conventional example,

FIG. 3 is an enlarged longitudinal sectional view of a main part of the conventional example of FIG. 2, 1; engine, 2; crankcase, 3; cylinder body, 4; cylinder head, 7; head cover, 8; intake pipe, 9; blow-by gas recirculation Pipe, 10; Push rod, 11; Tappet, 12; Cam, 13; Rocker arm, 14; Open / close valve, 19; Oil pan, 20; Push rod, 21; Inflow hole, 22; Outflow hole, 23; Hollow part, G Blow-by gas, L; Oil.

Claims (1)

[Scope of utility model registration request] 1. A hollow push rod has at least one blow-by gas inflow hole opened at a position slightly above the tappet disposition position, above the upper surface of the cylinder head, and above the upper end. A blow-by gas recirculation apparatus for an engine, characterized in that at least one blow-by gas outlet communicating with the inflow hole via a hollow portion is opened at a slightly lower portion.