JP2684638B2 - Oil pump arrangement structure for motorcycle engine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an oil pump arrangement structure in an engine, and particularly to an arrangement of pumps capable of avoiding an increase in engine width when two oil pumps are provided. Regarding the improvement of the structure.

[Conventional technology]

2. Description of the Related Art Conventionally, as a lubricating device for an engine, a single oil pump feeds the lubricating oil that has dropped into a relatively small oil pan provided at the bottom of the crankcase to an oil tank, and the lubricating oil from the oil tank is transferred to another Some oil pumps are configured to supply oil to the parts such as crankshaft bearings that require lubrication.

As the arrangement structure of each oil pump in such a lubricating device, conventionally, it is general that both pumps are arranged in series near the side wall of the crankcase (for example, Japanese Patent Laid-Open Publication No. Sho.
62-7910).

[Problems to be solved by the invention]

However, in the conventional oil pump arrangement structure described above,
Since the three oil pumps are arranged in series, there is a concern that the crankcase may largely project outward depending on the arrangement position, and the engine width may increase. To avoid this problem, both pumps may be arranged inside the crankcase (see, for example, Japanese Patent Laid-Open No. 59-60012). However, in this case, the arrangement position is restricted due to the relationship with other parts, which causes a problem that the degree of freedom in the layout design is significantly reduced.

In addition, the above-mentioned two pumps generally have different capabilities. In this case, it is advantageous in terms of cost to use the same pump and make the number of revolutions different,
In the case of the above-mentioned series arrangement, such a setting cannot be made.

The present invention has been made in view of the above-mentioned conventional problems, and when two oil pumps are arranged, it is possible to avoid an increase in the width of the engine and secure the degree of freedom in layout design of the engine. It is intended to provide a structure.

[Means for solving the problem]

Therefore, the present invention provides a first pump for supplying lubricating oil from an oil tank mounted on a vehicle body frame to a lubrication-required portion,
In an oil pump arrangement structure for a motorcycle engine, comprising: a second pump that feeds the lubricating oil that has fallen to an oil pan arranged at the bottom of the crankcase to the oil tank, the engine has a cam at one end of the crankshaft. A side chain type in which a shaft drive chain is arranged, wherein the first and second pumps are arranged in a crankcase at one end in the crankshaft direction where the camshaft drive chain is arranged and below the crankshaft. Arranged in parallel with the crankshaft and in parallel with each other, and a pump drive gear provided on the crankshaft meshes with an input gear of one of the first and second pumps;
It is characterized in that the first input gear is meshed with the second input gear of the other pump.

[Action]

According to the oil pump arrangement structure of the present invention, the first and second pumps are arranged parallel to the crankshaft and in parallel with each other at one end in the crankshaft direction where the camshaft drive chain of the crankcase is arranged. The bulging width of the case is about the same as that of the chain case part for the camshaft drive chain, and the expansion of the engine width can be suppressed accordingly. Also, in this case,
Since it can be arranged on the side wall of the crankcase, the degree of automation in the layout design is higher than that in the case where the crankcase is arranged inside.

Further, since the two pumps are arranged in parallel below the crankshaft and are driven by the drive gear and the first and second input gears, the two pumps can be arranged compactly and the overall engine can be made compact. Further, the pumps having the same specifications can be used at different rotation speeds by using input gears having different numbers of teeth, which is advantageous in terms of cost.

〔Example〕

 Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

1 to 5 are views for explaining one embodiment of the present invention.

In the drawing, reference numeral 1 denotes a motorcycle on which the engine of the present embodiment is mounted, and a front fork 4 for supporting a front wheel 3 at a lower end is supported at the front end of a body frame 2 so as to be steerable left and right. A rear arm 6 that pivotally supports the rear wheel 5 at the rear end is pivotally supported vertically at the lower end, and a large fuel tank 7 and a seat 8 are mounted on the upper portion in order from the front. An engine unit 9 is suspended and supported below the front part of the body frame 2.

The engine unit 9 is an air-cooled 4-cycle parallel 2
A cylinder type, a cylinder block 11, a cylinder head 12, and a head cover 13 are stacked on a front portion of an upper surface of a crankcase 10 in a state where the cylinder block 11, the cylinder head 12, and the head cover 13 are inclined forward by approximately 45 degrees with respect to a horizontal plane.

Above the left and right cylinders 11a and 11b of the cylinder block 11, pistons 14a and 14b and concave portions 12 of the cylinder head 12 are provided.
a and 12b, a combustion chamber 14 is formed. The intake and exhaust ports communicating with the combustion chamber 14 have three intake valves 15a and one exhaust valve 1a.
Two 5b are arranged. A driven sprocket 16c is fixed to the right end of the intake cam shaft 16a and the exhaust cam shaft 16b for the intake valve 15a and the exhaust valve 15b when viewed from the rear of the vehicle (the same applies hereinafter).

The pistons 14a, 14b are connected to the crank arm portions 18a, 18b formed by connecting a pair of webs of the crank shaft 18 with crank pins by connecting rods 17a, 17b, and both crank arms of the crank shaft 18 are connected. A portion between the portions 18a and 18b is pivotally supported by a central bearing 19c, and left and right outer portions are pivotally supported by left and right bearings 19a and 19b, respectively.

The crankcase 10 has an upper / lower split structure divided into upper and lower cases 23 and 24. The split surface A is inclined so that the front side becomes lower when mounted on a vehicle. Above left, right,
The center bearings 19a to 19c are formed at a portion closer to the front side of the division surface A. A pivot portion 24a for pivotally supporting the front end of the rear arm 6 is formed integrally with the rear end of the lower case 24.

A gearshift main shaft (main shaft) 32 is disposed on the rear side of the crankcase 18 of the upper case 23 and above the split surface A, and a gearshift main shaft 32 is located between the split surfaces and slightly behind the gearshift main shaft 32. A sub shaft (drive shaft) 35 is arranged. A wet multi-plate clutch 33 is attached to the right end of the transmission main shaft 32, and a reduction gear 33b fixed to an outer 33a of the clutch 33 meshes with a reduction gear 22 fixed to the crankshaft 18. There is. Further, the transmission gears 32a and 35a of the respective stages mounted on the transmission main shaft 32 and the auxiliary shaft 35 are in mesh with each other, thereby forming a constant mesh type transmission.

The left end of the transmission auxiliary shaft 35 projects outward from the left side wall of the crankcase 10, and a rear wheel drive sprocket 36 is mounted on the projecting portion, and between the sprocket 36 and the driven sprocket 5a of the rear wheel 5. The transmission chain 37 is wound.
A chain cover 38 is provided outside the drive sprocket 36 so as to cover it, and a case cover 42 is provided outside the chain cover 38. This chain cover 38
Is for shielding the mud splashed by the transmission chain 37 and the sprocket 36.

A front balancer shaft 47 is provided in a portion of the lower cover 24 in front of the crankshaft 18 and below the split surface A, and a rear balancer shaft 48 is provided in a portion of the upper cover 23 behind the crankshaft 18 and above the split surface A. Are arranged in parallel with the crankshaft 18, and the line connecting the shaft cores of both balancer shafts 47 and 48 is located in front of the shaft core of the crankshaft 18. For the front and rear balancer shafts 47 and 48, the support shaft 50 is inserted into the balancer body 49,
It has a structure in which a needle bearing 51 is arranged between the two,
Each of the conventional gears 47a and 48a meshes with a balancer gear 21 fixed to the crankshaft 18. Reference numeral 52 is a positioning plate that regulates the axial position of the balancer shafts 47 and 48, which is fixed to the crankcase.

A drive sprocket is located on the right side of the crankshaft 18
The sprocket 18c and the camshaft 16 are integrally formed.
A cam chain 20 is wound between the driven sprockets 16c of a and 16b. The cam chain 20 is arranged so as to pass through the cylinder head 12, the cylinder block 11, and the chain case portions 11c, 12c, and 23a that are bulged on the right side walls of the upper case 23. A tensioner 60 is disposed behind the cam chain 20, and the chain pressing member 60a of the tensioner 60 has its lower end pivotally supported by a pin 61a. Then, on the outside of the pin 61a, the upper and lower covers 2
The bolt 10a for connecting the pins 3 and 24 is positioned so as to be substantially orthogonal to the axis of the pin 61a, thereby preventing the pin 61a from coming off.

A portion of the right side wall of the crankcase 10 on the front side of the chain case portion 23a is relatively in the vehicle width direction because the case portion 23a and an oil pump housing case 61 described later are bulged rightward. A water pump 53 for circulating cooling water is disposed in the paragraph B in parallel with the crankshaft 18 in a stepped-down shape. The suction port 53a formed in the shaft core of the water pump 53 is connected to the radiator 62,
The discharge port 53b formed on the upper side in the tangential direction is connected to the front side of the cylinder block 11 and communicates with the water cooling jacket 11d. The driven gear 53d fixed to the inner end of the impeller shaft 53c meshes with the drive gear 47c fixed to the right end of the front balancer shaft 47.

A pump drive gear 25 is provided at the right end of the crankshaft 18.
Is installed. Below this pump drive gear 25,
A feed pump 26 for supplying the lubricating oil from the oil tank 63 having an oil cooler function to the lubricated parts such as the bearings 19a to 19c of the crankshaft 18 and the lubricating oil in the oil pan 28 are fed into the oil tank. The scavenging pump 27 for oiling is arranged at the right end in the crankshaft direction, that is, on the side of the chain case portion 23a that houses the camshaft drive chain 20, in parallel with the crankshaft 18, and in parallel with each other below the crankshaft 18. ing. Further, the pump drive gear 25 is replaced by the feed pump 26.
The input gear 26a of the
27 input gears 27a are sequentially meshed with each other, and these are the pump housing case mounted on the right side wall of the crankcase 10.
It is covered with 61. Suction port 27 of the scavenge pump 27
The b is connected to one end of a strainer housing 29 immersed in the oil pan 28, and the discharge port 27c is connected to the oil tank 63 by an oil hose 64. The suction port 26b of the feed pump 26 is connected to the oil tank 63 by an oil hose (not shown), and the discharge port 26c is
It is connected to a cleaner chamber 28a formed across both the oil pan 28 and the lower case 24. This cleaner room 28a
An oil cleaner 31 is housed inside, and a cap 30 is attached to the bottom surface of the cleaner chamber 28a. As a result, the cleaner chamber 28a has a three-tiered structure including the lower case 24, the oil pan 28, and the cap 30.

A cell motor 43 is mounted on a portion of the lower surface of the lower case 24 surrounded by the oil pan 28 and the cleaner chamber 28a, and a drive gear 43b attached to an output shaft 43a of the cell motor 43 is an idle gear. Through 45, it meshes with a starting gear 46 mounted on the crankshaft 18 through a one-way clutch.

 Next, the function and effect of this embodiment will be described.

In the apparatus of this embodiment, the front and rear balancer shafts 47 and 48 are driven by the rotation of the crankshaft 18, and the engine vibration is reduced. Further, the water pump 53 is driven via the rear balancer shaft 47, and the cooling water is circulated between the radiator 62 and the water cooling jacket 11d.

Further, the rotation of the crankshaft 18 causes the feed pump 2
6, the scavenge pump 27 is driven in sequence, and the oil tank 63
The lubricating oil in the bearings 19a to 1a
The lubricating oil dropped into the oil pan 28 while being fed to the lubrication-required portion such as 9c is fed again into the oil tank by the scavenging pump 27.

As described above, when two oil pumps are provided, if both pumps are arranged in series, the overall width tends to be widened due to the pump housing portion and the cover formed in the crankcase. There was a problem that there was a positional restriction. On the other hand, in this embodiment, the feed pump 26 and the scavenge pump 27 are arranged in the crankcase.
Since the 10 are arranged in parallel on the chain case portion 23a side, the bulging width of the crankcase 10 is substantially the same as the chain case portions 23a and 11c. Therefore, the expansion of the engine width can be suppressed while disposing the two pumps on the side wall of the crankcase 10. Further, since the two oil pumps 26, 27 are arranged in parallel below the crankshaft 18 and driven by the drive gear 25 and the input gears 26a, 27a, the two oil pumps 26, 27 can be arranged compactly. Furthermore, since the problem of widening the width is solved while arranging it on the side wall of the crankcase, there are almost no restrictions on the arranging position compared to the case of arranging it inside the crankcase, and the degree of freedom in arranging design is increased. Can be expanded. In addition,
In the present embodiment, pumps having different capacities are arranged, but pumps having the same specifications may be arranged, and the number of revolutions may be changed according to the drive gear ratio, so that a desired capacity difference may be produced.

In this embodiment, both pumps 26, 27 are connected to the crankcase 1
Since it is arranged in parallel on the side wall portion of 0, maintainability is good.

Furthermore, in the present embodiment, on the same side as the position where the oil pump is arranged, the chain case portion 23a and the pump housing case 61 are provided.
Since the water pump 53 is arranged in the paragraph B formed by and, it is possible to solve the problem of engine width expansion due to the arrangement of the water pump.

[Effects of the Invention] As described above, according to the engine oil pump arrangement structure of the present invention, the first and second pumps are provided on the lower side of the crankshaft on the side where the camshaft drive chain of the crankcase is arranged,
Since it is placed parallel to the crankshaft and parallel to each other, 2
It has the effect of avoiding the expansion of the engine width while arranging the two pumps on the side wall of the crankcase. Also, since the two pumps are arranged in parallel under the crankshaft and driven by gears, the two pumps can be made compact. There is an effect that the arrangement can be performed, the arrangement position is not so restricted, and the degree of freedom in the arrangement design can be secured.

[Brief description of the drawings]

1 to 5 are views for explaining an oil pump arrangement structure according to an embodiment of the present invention. FIG. 1 is a partial sectional side view of an engine adopting the structure, and FIG. A sectional plan view of the main part, FIG. 3 is a sectional front view of the main part, and FIG.
FIG. 5 is a sectional plan development view of the engine, and FIG. 5 is a left side view of a motorcycle equipped with the engine. In the figure, 9 is an engine unit, 10 is a crankcase, 18 is a crankshaft, 19a to 19c are bearings (portions requiring lubrication), 26
Is a feed pump (first pump), 27 is a scavenge pump (second pump), and 28 is an oil pan.

Claims (1)

(57) [Claims] Claim: What is claimed is: 1. A first pump for supplying lubricating oil from an oil tank mounted on a vehicle body frame to a lubrication-required portion, and a lubricating oil dropped on an oil pan arranged at the bottom of a crankcase to the oil tank. An oil pump arrangement structure for a motorcycle engine including a second pump for oiling, wherein the engine is a side chain type in which a camshaft drive chain is arranged at one end of a crankshaft,
The second pump is arranged in the crankcase at one end in the crankshaft direction where the camshaft drive chain is arranged and below the crankshaft, in parallel with the crankshaft and in parallel with each other. The pump drive gear provided is the first
An oil pump arrangement structure for a motorcycle engine, characterized in that an input gear of one of the second pumps is meshed with the first input gear and a second input gear of the other pump is meshed therewith.