JPH02201011A - Apparatus for lubricating motorcycle - Google Patents

Abstract

PURPOSE:To directly supply oil at a lower part of a piston to improve cooling efficiency by providing an oil passage tube from a joint face of a crank case and a side cover across a cam chain chamber to a lower part of the piston. CONSTITUTION:A crank shaft 5b is provided with a cam drive sprocket gear 21 an well as a cam chain chamber 23 above the gear 21. In the mentioned constitution, on a joint surface 31 on the side of a crank case 6, an oil passage tube 35 is inserted through a passage hole 34 drilled in parallel with the crank shaft 5b above the gear 21. The oil passage tube 35, after being passed through a cam chain 22 and a crank case side wall 7b, has its tip come to a lower part of a piston 2 located at a bottom dead center, that is, a slit 37 of a cylinder 1 to a crank web. This allows oil to be supplied directly from a clutch cover 30 to the lower part of the piston 2, improving cooling efficiency.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to an RAW4 device for a motorcycle engine that is an over-Rad cam type 4-stroke engine, and is particularly aimed at piston cooling. It is.

(Prior art) Most of the four-stroke engines installed in motorcycles are of the overhead cam type, and the cam chain chamber that houses the cam chain for driving the cam is integrated within the cylinder block and cylinder head. It is usually formed in

On the other hand, in order to lubricate such valve train cam mechanisms, other connecting rod big ends, crankshaft bearings, etc., oil is pumped up by an oil pump from an oil pan at the bottom of the crankcase and penetrates the thick part of the case. The oil is supplied through an oil passage formed by a concave groove formed on the surface mating with the oil passage and the attached side cover.

And the air between the cylinder and the piston, the small end of the connecting rod and the piston pin, and the cooling of the piston! There are some types, including JJ, that use an oil jet to supply ample oil to the bottom surface of the piston.

As shown in FIG. 9, this oil jet device is arranged so that the cylinder a is located directly below the lower edge of the piston b at the bottom dead center position.
Aim at the inner surface of the piston b through the gap between the lower end open part and the side surface of the outer peripheral part of the crank web C, and move it to the top of the 1111 wall e of the crankcase d! An oil jet f is embedded in one part. Oil is supplied to the oil jet f from an oil passage 9 that passes through a thick portion of the crankcase side wall e.

Furthermore, in the one shown in FIG. 10, an oil jet h is buried in a similar position, and oil is supplied through an oil passage j provided on the outer periphery of the crankshaft bearing i.

However, since the fitting hole I for embedding the oil jets f and h is obliquely drilled, it is a separate process from other machining processes, which increases jig costs, equipment costs, and man-hours. The cost will be high. Furthermore, there are many parts arranged on the wall e of the crankcase m, and it may be difficult to see the oil passage from the bottom of the case while avoiding interference with these parts.

Another method for forming the oil passage is to form a groove formed in the mating surfaces of a side cover attached to the wall of the crankcase ll1l, for example, a clutch cover m and a crankcase d, so that the oil passage becomes a gear when they are joined. The one set is valid. The structure is simplified by guiding the connecting oil passages to the oil jets f and h from appropriate positions.

However, the cam chain chamber is
, o, clutch cover m and crankcase ll
In the case of a structure existing between the wall 1l and the wall e, it is necessary to bypass this part, and there is a problem that the structure cannot be simplified.

(Problem to be solved by the invention) This invention was made in view of the above problems.
A cylinder block with a cam chain chamber formed at -m of the cylinder head can supply oil to the oil jet placed under the piston at the bottom dead center position without using a complicated oil passage and with good workability. The purpose of the present invention is to provide an automatic two-wheel heavy-duty engine equipped with the following features.

[Structure of the invention]

(Means for Solving the Problem) In order to achieve the above object, a lubricating device for a motorcycle engine according to the present invention is provided on a crankshaft that protrudes outward from an m-wall of a crankcase and is covered with a side cover. In a motorcycle engine in which a cam drive sprocket gear is arranged and a cam chain chamber is formed on one side of the cylinder block and cylinder head above the gear, on the mating surface of the crankcase to which the side cover is attached,
A through hole is drilled above the cam drive sprocket gear, and an oil passage pipe with an oil jet at the tip is inserted into this hole. and passes through the side wall of the crankcase so that its tip faces into the cylinder below the piston at the bottom dead center position, and oil flows from the oil passage formed on the mating surface of the crankcase and side cover. is introduced, and the structure is such that oil is injected onto the underside of the piston from an oil jet at the tip.

(Function) With this structure, oil is directly supplied to the lower surface of the piston from the oil passage formed in the mating surface of the crankcase and side cover through the oil passage pipe inserted across the cam chain chamber. can be injected.

Therefore, there is no need to drill an oil passage in the thickness of the bottom or side wall of the crankcase, and the insertion hole for the oil passage pipe is perpendicular to the mating surface, so it can be machined at the same time as the screw hole for attaching the side cover. High productivity. Furthermore, the oil passage pipe can be drained by simply removing the side cover, making the oil jet easier to maintain.

(Example) Below, the drawings which are examples of the present invention will be explained in detail.

FIG. 1 is a longitudinal sectional front view of a single cylinder four-stroke engine equipped with a lubricating device according to the present invention, and FIG.
It is a longitudinal side view taken along arrow A-A in FIG.

A piston 2 housed in a cylinder 1 is connected to a funnel rod 3.
It is connected to the crank 4 via the crank 4, and moves up and down as the crank 4 rotates. The crank 4 is connected to the I! of the crankcase 6 by crankshafts 5a and 5b at both ends. wall 7a,
7b, and its crankshafts 5a, 5b are provided to protrude outward from the side walls 7a, 7b.

A cylinder head 9 is stacked on a cylinder block 8 forming a cylinder 1, and an intake passage 11 and an exhaust passage 12 are introduced into a combustion chamber 10 on the lower surface thereof, and are controlled to open by an intake valve 13 and an exhaust valve 14. Both valves 13 and 14 are connected to the intake cam 1 on the camshaft 15 which is pivotally supported on the upper surface of the cylinder head 9.
6. It is opened and closed by the rotation of the exhaust cam 17 via the rocker arms 18 and 19.

The camshaft 15 is 1. A cam driven sprocket gear 20 is pivotally supported at one end and is driven via a cam chain 22 suspended between it and a cam drive sprocket gear 21 on the crankshaft 5b. This cam chain 22 runs within a cam chain chamber 23 formed in the cylinder block 8 and cylinder head 9.

A primary drive gear 24 is further fixed to the crankshaft 5b and meshes with a primary driven gear 26 on the countershaft 25.

Rotation is transmitted to the counter shaft 25 via an IFLrM clutch 27, and rotation is transmitted to the drive shaft 28 via a mission gear mechanism (not shown). 29
is the output drive sprocket gear 7.

The crankshaft 5b, cam drive sprocket gear 21, primary drive gear 24, primary driven gear 26, n-closing latch 27, and a portion of the countershaft 2-5 are covered by a clutch cover 30 attached to one side of the crankcase 6. covered by.

Next, as shown in FIG. 3 and FIG.
is formed, and by aligning the crankcase 6, a gear is formed, and the oil sent out by the oil pump from the oil pan at the bottom of the crankcase is guided through this groove 32 as part of the oil passage. ing.

On the other hand, an oil passage pipe 35 is inserted into a through hole 34 formed in the mating surface 33 of the crankcase all at a position above the cam drive sprocket gear 21 and parallel to the crankshaft 5b.

This oil passage pipe 35 passes through the annular part of the cam chain 22 suspended upward from the cam drive sprocket gear 21, and further passes through the crankcase copper 17b. It is inserted to a position directly below the lower end edge and facing a gap 37 between the lower end open portion of the cylinder 1 and the outer peripheral side surface of the crank web 36.

As shown in FIG. 5, FIG. 6, and FIG. 7, the oil passage pipe 35 has an oil jet 38 at its tip 35a, and its tail *35b is open and exposed, with a part extending outward. A locking piece 39 is formed by bending at a right angle. When inserted into the crankcase 6 as described above, the locking piece 39 fits into the locking groove 40 formed in the mating surface 33 and is positioned in the rotation direction, so that the oil jet 38 at the tip The position of the piston 2 is controlled and fixed so as to aim at the lower surface of the piston 2 from the gap 37, and the end surface of the tail end 35b is the mating surface 3.
3 and communicates with the groove 32.

In this way, even if the cam chain chamber 23 exists between the clutch cover 30 and the crankcase 6, the oil passage pipe 35 is guided directly from the clutch cover 30 to below the piston at the bottom dead center position beyond the cam chain chamber 23. Cooling oil can be supplied to the lower surface of the piston 2 by an oil jet installed at the tip.

Therefore, there is no need to provide an oil passage within the wall thickness of the crankcase 1l17b, and the oil passage formed on the mating surface of the crankcase 6 and the clutch cover 30 is used.
Oil can be carried to the upper end of the side wall 7b, greatly improving workability and reducing costs, and the oil passage pipe can be taken out by removing the clutch cover, making maintenance of the oil jet easy.

Note that a side cover other than the clutch cover 30, such as a magnet cover side, can also be configured in the same way.

〔Effect of the invention〕

As mentioned above, the motorcycle engine according to the present invention has v
Jn1i&w runs an oil passage pipe from the mating surface with the side cover of the crankcase, through the ring of the cam chain, and under the piston at the bottom dead center position, and introduces the oil from the oil passage provided on the mating surface. The oil is supplied to the bottom surface of the piston through the oil jet at the tip, which allows for cooling of the piston with a simple structure, good workability, reduced cost, and excellent maintainability. There is an effect that can be done.

[Brief Description of the Drawings] Fig. 1 is a longitudinal sectional front view of a single cylinder 4-cycle engine equipped with an rIJ locking device according to an embodiment of the present invention, and Fig. 2 is a longitudinal sectional side view taken along arrow A-A in Fig. 1. , Fig. 3 is an enlarged longitudinal sectional front view of the main part of Fig. 1, Fig. 4 is an enlarged longitudinal sectional side view of the main part of Fig. 2, and Fig. 5 is an enlarged view of the oil passage pipe used in Fig. 1. FIG. 6 is a sectional view taken along the arrow B-8 in FIG. 5, FIG. 7 is a sectional view taken along the line C-C in FIG. 5, and FIG. 9 and 10 are longitudinal sectional front views showing the conventional piston cooling Vt1Fff, respectively. 1...Cylinder, 2...Piston, 5b...Crankshaft, 6...Crankcase, 7b...8
Side wall, 21...Cam drive sprocket gear, 22
...Cam chain, 23...Cam chain chamber, 30
...Clutch cover (side cover), 31.33.
...Matching surface, 32...Concave groove, 35...Oil passage pipe, 38...Oil jet.

Claims (1)

[Claims] A two-wheeled motor vehicle in which a cam drive sprocket gear is arranged on a crankshaft that protrudes outward from the side wall of the crankcase and is covered with a side cover, and a cam chain chamber is formed on one side of the cylinder block and cylinder head above the cam drive sprocket gear. In the engine, a through hole is bored in the mating surface of the crankcase to which the side cover is attached above the cam drive sprocket gear, and an oil passage pipe with an oil jet at the tip is inserted into this through hole. The oil passage pipe is set so as to pass inside the annular shape of the cam chain, penetrate the side wall of the crankcase, and face the inside of the cylinder below the piston at the bottom dead center position. A lubricating device for a motorcycle engine, characterized in that oil is introduced from an oil passage formed in a mating surface between a crankcase and a side cover, and the oil is injected onto the lower surface of a piston from an oil jet at the tip. .