JPH08100652A - Water pump and accessories driving structure of water-cooled engine - Google Patents

Abstract

PURPOSE: To downsize an engine, reduce number of items thereof, and improve dissasembly/maintenance performance of a water pump and accessories. CONSTITUTION: A pump driving shaft 36 for operating a water pump 30 is connected to an accessory driving shaft (a governor driving shaft 38) for operating an accessory (a governor device) in a rotationally integral form. Connection parts 41A, 41B between the pump driving shaft 36 and the accessory driving shaft 38 are formed in a detachable manner in an axial direction. Bearings 44 (44a, 44b), 45 are arranged on both ends of the connection parts 41A, 41B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water pump for a water-cooled engine in which a water pump provided in a crankcase and accessories are driven by a crankshaft, and an accessory drive structure.

[0002]

2. Description of the Related Art A general water-cooled engine mounted on a motorcycle or the like drives a water pump for circulating cooling water provided in a crankcase by a crankshaft. In addition, accessories other than the water pump, such as a governor device and a balancer device, may be provided in the crankcase, and such accessories are also driven by the crankshaft.

FIG. 4 is a cross-sectional view of a crankcase showing an example of such a water-cooled engine. In this water-cooled engine, a crankshaft 102 is rotatably supported in a crankcase 101, and a governor device 103 for operating, for example, an exhaust timing control device (not shown) is provided adjacent to the crankshaft 102. Is installed as an auxiliary machine, and a water pump 104 is provided outside the governor device 103.

A governor drive shaft 105 for operating the governor device 103 and a pump drive shaft 106 for operating the water pump 104 are axially supported in the crankcase 101 so as to be displaced to the front and rear and to the left and right. Then, the drive gear 107, which is integrally provided with the crankshaft 102 so as to rotate, is the governor drive shaft.
It meshes with the governor driven gear 108 fixed to 105,
A pump drive gear 109 provided adjacent to the governor driven gear 108 meshes with a pump driven gear 110 fixed to the pump drive shaft 106.

Therefore, the rotation of the crankshaft 102 is transmitted to the governor device 103 via the drive gear 107 and the governor driven gear 108, and further to the water pump 10 via the pump drive gear 109 and the pump driven gear 110.
Propagated to 4.

[0006]

However, as described above, the drive shaft 105 of the governor device 103 and the water pump 10 are
Since the four drive shafts 106 are independently supported in the crankcase 101 by being displaced in the front-rear direction and the left-right direction, the horizontal width and the vertical width of the crankcase 101 are expanded, and the engine is enlarged.

Further, both the drive shafts 105 and 106 are supported by dedicated bearings, respectively, and a dedicated gear (a pump drive gear 109 and a pump driven gear 110) for interlocking the two shafts 105 and 106 is required separately. Therefore, the number of parts is increased, the engine is difficult to assemble, and the manufacturing cost is increased.

Further, when the governor device 103 is disassembled for maintenance, the water pump 104 also has to be disassembled, so disassembly and maintenance is very poor.

The present invention has been made in order to solve such problems, and aims at downsizing the engine and reducing the number of parts, and at the same time, improving the disassembly and maintenance of the water pump or the auxiliary machinery. It is an object of the present invention to provide a water-cooled engine water pump and an auxiliary machine drive structure that can be used.

[0010]

In order to achieve the above-mentioned object, a water pump for an water-cooled engine and a drive structure for accessories according to the present invention are provided in a crankcase as described in claim 1. In a water-cooled engine water pump and an accessory drive structure in which a water pump for water circulation and an accessory are driven by a crankshaft, a pump drive shaft for operating the water pump and an accessory for operating the accessory. The machinery drive shaft was connected to rotate integrally.

Further, as described in claim 2, the connecting portion between the pump drive shaft and the auxiliary equipment drive shaft is configured to be axially separable, and bearings are arranged on both sides of the connecting portion.

[0012]

According to the first aspect of the present invention, the pump drive shaft and the auxiliary device drive shaft are unified so that the lateral width and vertical width of the crankcase are narrowed and the engine is made compact. Moreover, since the number of bearings is reduced and a gear for interlocking the shafts is not necessary, the number of parts is significantly reduced.

In addition to this, according to the second aspect, either the pump drive shaft or the auxiliary machinery drive shaft can be separated from the connecting portion and taken out of the crankcase. When the drive shafts are reconnected, the bearings arranged on both sides of the connection parts prevent the drive shafts from being misaligned with each other, so that the disassembly and maintenance of the water pump or the auxiliary machinery are improved.

[0014]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical cross-sectional view of a water-cooled engine to which a water pump and an accessory drive structure according to the present invention are applied, and FIG. 2 is a horizontal cross-sectional view taken along line II-II of FIG. .

The water-cooled engine 1 is a two-cycle single-cylinder engine mounted on a motorcycle, for example.
The right side is the front and the left side is the rear. On the upper surface of the crankcase 2 of the water-cooled engine 1, a cylinder assembly 5 including a cylinder block 3 and a cylinder head 4 is provided upright.

A crankshaft 6, a counter shaft 7, and a drive shaft 8 are rotatably supported in the crankcase 2 so as to extend in the vehicle width direction from the front.
The drive gear 10 integrally provided on the counter shaft 7
While always meshing with the driven gear 11 mounted on the shaft, a constantly meshing multi-stage transmission 12 is provided between the counter shaft 7 and the drive shaft 8. A clutch mechanism 13 is installed on the counter shaft 7.

On the other hand, a cylindrical cylinder bore 14 is formed in the cylinder block 3, and a combustion chamber 15 which is aligned with the cylinder bore 14 is formed in the cylinder head 4. Further, an exhaust port 16 is provided, for example, on the front side of the cylinder bore 14, and a plurality of scavenging ports 17 are provided around the exhaust port 16. An intake passage 19 extending obliquely upward and rearward is provided on the rear side of the cylinder bore 14, a reed valve (not shown) is built in the intake passage 19, and a carburetor (not shown) is connected to the outside of the intake passage 19. .

A piston 20 is placed in the cylinder bore 14.
Is slidably inserted, and the piston pin of this piston 20
21 and a crank pin eccentrically mounted on the crank shaft 6
22 and 22 are connected by a connecting rod 23. Therefore, the reciprocating motion of the piston 20 in the cylinder bore 14 is converted into the rotary motion of the crankshaft 6, and the rotation of the crankshaft 6 is taken out as the output of the water-cooled two-cycle engine 1 via the counter shaft 7 and the drive shaft 8.

A water jacket 24 for circulating cooling water is formed around the cylinder bore 14 and the combustion chamber 15.
The water jacket 24 includes a cylinder jacket 25 surrounding the cylinder bore 14 and the exhaust port 16
An exhaust port jacket 26 that surrounds the periphery of the combustion chamber 15 and a combustion chamber jacket 27 that covers the periphery of the combustion chamber 15 are connected to each other, and a cooling water outlet provided at the upper portion of the cylinder head 4 is formed.
28 is connected to the combustion chamber jacket 27.

By the way, the crankcase 2 is a two-part type in which the left case half 2L and the right case half 2R are divided along a joint surface C orthogonal to the axial direction of the crankshaft 6. A magnet cover 2a is mounted on the left side of the case half 2L, and a clutch cover 2b is mounted on the right side of the case half 2R as separate parts. It should be noted that FIG. 1 shows a state in which the right case half 2R is removed.

A water pump 30 for circulating cooling water in the water jacket 24 is installed in front of the crankcase 2. The pump chamber 31 of the water pump 30 is formed so as to straddle the mating surface C of the crankcase 2, for example.
A suction passage 32 and a discharge passage 33 which are connected to the crankcase 2 are formed in the crankcase 2.

The suction passage 32 is formed, for example, on the case half body 2L side so as to extend from the center of the pump chamber 31 to the left side of the vehicle body.
Has been press-fitted. A hose (not shown) is connected to the union 34, and the other end of the hose is connected to a radiator. The discharge passage 33 is formed in the case half 2L and the case half 2R so as to extend tangentially upward from the peripheral portion of the pump chamber 31 and communicate with the exhaust port jacket 26.

A left end portion of a short pump drive shaft 36 extending in the vehicle width direction projects into the pump chamber 31, and an impeller 37 provided integrally with this portion for rotation rotates in the pump chamber 31. ing.

A governor drive shaft 38 serving as an accessory drive shaft is rotatably connected to the pump drive shaft 36 at the right end portion of the pump drive shaft 36. Is equipped with a governor device 39 as an accessory.
The governor device 39 is a device for interlocking the exhaust timing control device 40 shown in FIG. 1 with the rotation speed of the crankshaft 6.

Connection between pump drive shaft 36 and governor drive shaft 38
41 is configured to be separable in its axial direction, and FIG. 3 shows a structural example of the connecting portion 41.

Since the connecting portion 41A shown in FIG. 3 (a) is formed on the shaft core portion of the pump drive shaft 36, the pump drive shaft 36 is formed by fastening the male screw 43 of the left end portion of the governor drive shaft 38 to the screw 42. And the governor drive shaft 38 are connected.

Here, a bearing 44 and a bearing 45 are arranged on both sides of the connecting portion 41A, and the bearing 44 is the pump drive shaft.
The shaft 36 is supported, and the bearing 45 supports the vicinity of the left end portion of the governor drive shaft 38. The right end of the governor drive shaft 38 is rotatably supported by a bearing 46 fitted in the clutch cover 2b (see FIG. 2).

A hexagon wrench fitting hole 47 is provided at the left end of the pump drive shaft 36, and a spanner fitting portion 48 is provided at the right end of the governor drive shaft 38. Therefore, an unillustrated hexagon wrench is inserted from the suction passage 32, the hexagon wrench is fitted into the hexagon wrench fitting hole 47, the clutch cover 2b is removed, and a spanner is fitted into the spanner fitting portion 48. , By twisting the hexagon wrench and spanner to rotate the pump drive shaft 36 and the governor drive shaft 38 in opposite directions,
The fastening of the connecting portion 41A is loosened, and the governor drive shaft 38 can be pulled out to the right together with the governor device 39.

The connecting portion 41B shown in FIG. 3 (b) is formed as a dog cam between the right end of the pump drive shaft 36 and the left end of the governor drive shaft 38. And pump drive shaft
Bearings 44a, 44b for supporting the 36 and a bearing 45 for supporting the left end of the governor drive shaft 38 are arranged on both sides of the connecting portion 41B. In the case of this connecting portion 41B, the governor drive shaft 38 can be pulled out to the right together with the governor device 39 simply by removing the clutch cover 2b.

The structure of the connecting portion 41 is such that the pump drive shaft 36
As long as the governor drive shaft 38 and the governor drive shaft 38 can be separated in the axial direction, the configuration is not limited to the above-mentioned configuration and may be another configuration.

By the way, the crankshaft 6 and the governor drive shaft 38
An intermediate shaft 50 is rotatably supported by bearings 51, 52 between and, and a first intermediate gear 53 and a second intermediate gear 54 are rotatably integrated with the intermediate shaft 50. The first intermediate gear 53 located on the inner side meshes with the drive gear 10 provided on the crankshaft 6, and the second intermediate gear 54 located on the outer side is a governor driven gear 55 provided on the governor device 39.
Meshes with.

Therefore, the rotation of the crankshaft 6 depends on the intermediate shaft.
It is transmitted to the governor drive shaft 38 and the pump drive shaft 36 via 50, and the water pump 30 and the governor device 39 are driven.

When the impeller 37 of the water pump 30 rotates, the cooling water that has undergone heat exchange by the radiator is sucked into the pump chamber 31 from the suction passage 32 and discharged from the discharge passage 33. The discharged cooling water circulates through the exhaust port jacket 26, the cylinder jacket 25, and the combustion chamber jacket 27 in this order to cool the entire cylinder assembly 5. After that, the cooling water is taken out from the cooling water take-out port 28 and is again flowed to the radiator for heat exchange.

According to the above-described structure, first, the pump drive shaft 36 and the governor drive shaft 38 are integrally connected to each other by rotation, so that the horizontal width and the vertical width of the crankcase 2 are narrowed and the water-cooled engine is reduced. 1 is made compact. Further, since the number of bearings is reduced and a gear for interlocking the shafts is not required, the number of parts of the water-cooled engine 1 is significantly reduced, its assembly is facilitated, and the manufacturing cost is reduced.

The connecting portion 41 (41A, 41B) between the pump drive shaft 36 and the governor drive shaft 38 is configured to be axially separable, and bearings 44 (44a, 44b), 45 are provided on both sides of the connecting portion 41. Since it is arranged, in the case of this embodiment, only the governor drive shaft 38 is connected.
It can be taken out of the crankcase 2 by disconnecting it from the crankcase 2. In addition, when reconnecting the separated governor drive shaft 38, the bearings 44, 45 arranged on both sides of the connecting portion 41 are used to connect the drive shaft 36, 38 to each other. Since the misalignment is prevented, the governor drive shaft
The disassembly and maintainability of 38 is greatly improved.

In this embodiment, the governor drive shaft 38 can be taken out from the crankcase 2 by dividing the connecting portion 41, but both the pump drive shaft 36 and the governor drive shaft 38 are crankcased. If it is configured so that it can be taken out from 2, the disassembly and maintainability can be further improved.

[0037]

As described above, a water-cooled engine water pump and an accessory drive structure according to the present invention include a pump drive shaft that operates the water pump and an accessory drive shaft that operates the accessories. Since the and are connected in an integrated manner, the horizontal and vertical widths of the crankcase are narrowed, which can greatly contribute to the compactness of the engine.In addition, the number of bearings is reduced and the gears that link the shafts are not required.
The number of parts of the engine is greatly reduced to facilitate the assembly and reduce the manufacturing cost.

In the water-cooled engine water pump and accessory drive structure according to the present invention, the connecting portion between the pump drive shaft and the accessory drive shaft is configured to be axially separable, and the connect portion is also provided. Since the bearings are placed on both sides of
Either the pump drive shaft or the accessory drive shaft can be separated from the connecting part and taken out of the crankcase.When connecting the separated drive shaft again, bearings placed on both sides of the connecting part can be used. Since misalignment between the drive shafts is prevented, disassembly and maintenance of the water pump or accessories are improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a water-cooled engine to which the present invention is applied.

FIG. 2 is a cross-sectional view developed along the line II-II in FIG.

FIG. 3 shows an embodiment of the present invention, in which (a) and
(b) is sectional drawing which shows the constructional example of each connection part.

FIG. 4 is a transverse cross-sectional view of a crankcase of a water-cooled engine showing a conventional technique.

[Explanation of symbols]

 1 Water-cooled engine 2 Crankcase 6 Crankshaft 30 Water pump 36 Pump drive shaft 37 Impeller 38 Governor drive shaft 39 Governor device 41 (41A, 41B) as an auxiliary machine Connection part 44 (44a, 44b), 45 bearing

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location F16D 1/06 3/04 A

Claims (2)

[Claims] 1. A water pump for a water-cooled engine, in which a water pump for circulating cooling water provided in a crankcase and auxiliary machinery are driven by a crankshaft, and a drive mechanism for auxiliary machinery, which pump operates the water pump. A water pump for a water-cooled engine and an accessory drive structure, wherein a drive shaft and an accessory drive shaft for operating the above-mentioned accessories are connected integrally in rotation. 2. The water for a water-cooled engine according to claim 1, wherein the connecting portion between the pump drive shaft and the auxiliary equipment drive shaft is configured to be axially separable, and bearings are arranged on both sides of the connecting portion. Pump and auxiliary machinery drive structure.