JP3154693B2 - Starting device for vehicle engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a starting apparatus for a vehicle engine in which a crankshaft is driven by a starting motor via a starting gear train, and more particularly to a starting apparatus for a vehicle engine suitable for a motorcycle having a plurality of cylinders. Related to the device.

[0002]

2. Description of the Related Art As a conventional starting device for a vehicle engine, there is a starting device described in Japanese Utility Model Publication No. 2-18284. As shown in FIG. A flanged holder 110 is fixed to the end of the crankshaft 101 projecting toward
An outer ring 105 for a one-way clutch is fixed to a flange portion 108 together with a rotor 109 for a generator. An inner ring boss 112 is rotatably fitted to the crankshaft 101 inside the outer ring 105, and a cam member such as a sprag 107 is disposed between the outer ring 105 and the inner ring 112. A free wheel gear 111 is provided on the inner ring boss 112.
Are fixed and mesh with the idle small gear 117 of the starting system gear train. In short, at the end of the crankshaft 101,
One-way clutch and free wheel gear 11 for starting
The free wheel gear 111 is stopped with respect to the rotating crankshaft 101 during operation of the engine.

[0003]

In the prior art shown in FIG. 4, a one-way clutch and a free wheel gear 111 for starting are arranged in parallel between a generator rotor 109 and a main bearing housing 103. As the length from the journal 102 to the rotor 109 increases, the overall length of the crankshaft also increases, and the engine width increases. In particular, in a motorcycle, the bank angle is limited by an increase in the engine width.

[0004]

According to a first aspect of the present invention, there is provided a vehicle engine starting device, comprising:
A primary gear 20 connected to a gear mechanism for driving wheels is formed on the crankshaft 1, and separately from the primary gear 20,
A starting gear 23 is formed on the outer peripheral surface of the crank web 8 of the crankshaft 1 by directly cutting the gear. The starting gear 23 is used as a starting drive gear 35 of a starting system gear train 29 connected to a starting motor 33. It is characterized in that it meshes with the balancer gear 26 of the balancer shaft 25 as a balancer drive gear in addition to the meshing.

According to a second aspect of the present invention, the crankshaft 1
A primary gear 20 connected to a gear mechanism for driving wheels is formed, and a starting gear 23 is provided on the crankshaft 1 separately from the primary gear 20, and first and second starting gears are provided in parallel with the crankshaft 1. Support shafts 31 and 32 are provided, and the starting gear 2 is provided.
As a starting system gear train 29 that is connected to the starting motor 33 from 3, on the first support shaft 31, a starting drive gear 35 meshing with the starting gear 23, and the starting drive gear 35 via a one-way clutch 48. A free wheel gear 36 to be connected is arranged, and on the second support shaft 32, an idle small gear 67 meshing with the free wheel gear 36, and an output of the starting motor 33 which rotates integrally with the idle small gear 67 and rotates. A starting device for a vehicle engine, wherein a large idle gear 68 meshing with a gear 34 is arranged.

According to a third aspect of the present invention, in the vehicle engine starter according to the second aspect, the crankcase 2 houses a crankshaft at a front portion thereof, and has a transmission gear chamber 75 behind the crankshaft housing portion. The first support shaft 31 is disposed rearward above the crankshaft 1, the second support shaft 32 is disposed rearward above the first support shaft 31, and the starting motor 33 is disposed above the second support shaft 32. Is also arranged forward.

According to a fourth aspect of the present invention, in the vehicle engine starting device according to the second or third aspect, the first and second support shafts and the starting motor are arranged on an upper side of a vertically split crankcase 2. The starting device for a vehicle engine according to claim 2 or 1, wherein the starting gear is also used as a balancer driving gear.

[0008]

[0009]

[0010] By rotating the starting motor, the starting rotational force is directly transmitted from the output gear to the crank web of the crankshaft via the idle large gear, the idle small gear, the free wheel gear, the one-way clutch and the starting drive gear. The power is transmitted to the toothed starting gear to start the crankshaft. After the end of the start, only the start drive gear idles with the start gear of the crankshaft at all times during the operation of the engine, and the other gears in the start train are stopped.

A one-way clutch, a free wheel gear and the like are mounted on the crankshaft by directly cutting the starting gear on the crank web on the crankshaft and meshing with the starting drive gear of the starting gear train. There is no need to secure space, and the crankshaft width is reduced.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic cross-sectional view of a four-cylinder engine for a motorcycle to which the present invention is applied (a schematic cross-sectional view corresponding to a II-II section in FIG. 3). Since it extends in the left-right direction, the direction of the crankshaft center line O1 will be described below as the left-right direction. The cylinder block 4 includes first to fourth cylinders 3-1, 3-2, 3-cylinders.
3, 3-4, and is coupled to the upper end of the crankcase 2, and a piston 11 is fitted into each of the cylinders 3-1, 3-2, 3-3, 3-4. Crankcase 2
The main bearing housing 5 is positioned between the left and right ends and each cylinder.
Each journal 7 of the crankshaft 1 is rotatably supported on each main bearing housing 5 via a bearing metal.

The crankshaft 1 includes first to fourth cylinders 3
-1, 3-2, 3-3, 3-4, the crank pin 6, the journal 7, and the crank web (crank arm) 8-1, which integrally connects the crank pin 6 and the journal 7 to each other. 8-2, 8-3, 8-4, 8-5, 8
-6, 8-7 and 8-8. Each crank pin 6 is pivotally connected to each piston 11 via a connecting rod 10.

A rotor 15 for a generator is fixed to one end, for example, the left end of the crankshaft 1, and a cam chain drive gear 16 is integrally formed at the other end. Of the crank webs 8, the rightmost crank web 8-8 is
A primary gear 20 for driving a wheel is directly toothed on the outer peripheral surface thereof, and the primary gear 20 is formed on a shift input gear 21 of a transmission gear mechanism. Are engaged.

Apart from the wheel driving primary gear 20, the right crank web 8-6 for the third cylinder is also formed in a circular shape centered on the crank axis O1, and the starting gear 23 is directly toothed on the outer peripheral surface. It has been cut. The starting gear 23 meshes with a starting drive gear 35 of a starting system gear train 29, and a balancer gear 26 of the balancer shaft 25
Are also engaged. That is, the gear 23 is provided as a balancer driving and starting gear.

The configuration of the starting device will be described. FIG. 3 is a longitudinal side view (a sectional view taken along the line III-III in FIG. 2) of the starting device.
The state of the third cylinder piston 11 is shown at the top dead center position. In FIG. 3, a first support shaft 31 for starting is disposed above and behind the crankshaft 1, and a second support shaft 32 for starting is disposed above and behind the first support shaft 31.
A starting motor 33 and an output gear (pinion gear) 34 are arranged in front of the second support shaft 32, and the output gear 34 meshes with a front end portion of the large idle gear 68. The crankcase 2 is divided into an upper case member 2a and a lower case member 2b with an upper case member 2a and a lower case member 2b separated by a crankshaft center line O1, and both of the support shafts 31, 32 and the starting motor 33 are both upper case members 2a. Fixed to. A transmission gear chamber 75 is formed at the rear of the crankshaft 1. Inside the transmission gear chamber 75, an input shaft 73 (simply indicated by a solid circle) and an output shaft (simply indicated by a solid circle) from the front side. Display) 7
The crank breather chamber 17 is formed integrally with the upper case member 2a above the transmission gear chamber 75 and behind the first and second support shafts 31 and 32. ing.

In FIG. 2 showing an enlarged cross-sectional view taken along the line II-II of FIG. 3, the first support shaft 31 is supported by a pair of support holes 38 and 39 formed in the upper case member 2a. And the retaining plate 41 and the bolts 42 and 43
As a result, an oil passage 44 is formed in the shaft center portion, and the oil passage 44 communicates with a lubricating oil supply oil passage 46 formed in the wall of the crankcase 2.

On the first support shaft 31, the starting drive gear 35 is arranged at the same position in the axial direction as the starting gear 23, and a free wheel gear 36 is located on the left of the starting drive gear 35.
Are disposed, and a sprag type (cam type) one-way clutch 48 is disposed between the two gears 35 and 36. The starting drive gear 35 is integrally formed with a boss 50 extending leftward (to the free wheel gear side) at an inner peripheral end, and integrally formed with a one-way clutch outer ring 52 projecting leftward at an outer peripheral end. An annular recess 51 is formed in the intermediate wall (web) and is connected to the annular space between the outer ring 52 and the boss 50. The boss portion 50 is connected to the first
Is rotatably supported by the support shaft 31.

In the free wheel gear 36, a wide inner peripheral boss portion 55 is rotatably fitted directly on the outer peripheral surface of the first support shaft 31, and the right wheel portion of the inner peripheral boss portion 55 (starting drive). On the gear side portion), a starting drive gear 3 extending rightward is provided.
The one-way clutch inner ring 56 is formed integrally with the outer peripheral surface of the boss portion 50 of the No. 5 with a radial gap d1 therebetween. Numerous sprags (cams) 60 for a one-way clutch are arranged between the inner wheel 56 and the outer wheel 52, and the free wheel gear 36 is connected to the starting drive gear 35 as is well known.
The torque is transmitted only to the motor. Sprag 6
0, that is, the clutch sliding portion width W1 is completely contained within the width W2 of the needle bearing 53, and
About half of the tooth width of the starting drive gear 35 is inserted.

On the left side of the free wheel gear 36 and the right side of the starting drive gear 35, a collar 5 for a spacer is provided.
7, 58 are fitted to position both gears 36, 35 in the axial direction. A plurality of radial oil grooves 59 are formed on the left end surface of the boss 50 of the starting drive gear 35 so that the inner race 5
6 faces the bottom surface of the annular concave portion 51 with a gap d2 therebetween, and a radial oil passage 61 from the oil passage 44 to the needle bearing 53 is formed in the first support shaft 31. And the gap d1 between the oil groove 59 and the inner peripheral surface of the inner ring.
The gap d2 at the tip of the inner ring constitutes a lubricating oil path from the needle bearing 53 to the sliding portion of the sprag 60.

The second support shaft 32 is connected to the upper case member 2a.
The support holes 62, 63 are formed in a two-sided manner and fixed by an L-shaped retaining plate 64 and bolts 66. A small idle gear 67 meshing with the free wheel gear 36 and a large idle gear 68 with a torque limiter are rotatably fitted on the second support shaft 32. The large idle gear 68 is a taper fit for the torque limiter. The inner member 68a is spline-fitted to the boss portion of the idle small gear 67, and the outer member 68b is connected to the output gear of the starting motor 33 as described above. 34 is engaged. The taper fitting portion 69 exerts a torque limiter function of slipping at a predetermined rotational torque or more by generating a frictional force by the disc spring 71.

The starting motor 33 is fitted in a mounting hole 72 of the upper case member 2a, and is fastened to the upper case member 2a by a mounting bolt (not shown).

[0023]

When the engine is started, when the starting motor 33 shown in FIG. 2 is operated, the starting torque is transmitted from the output gear 34 to the large idle gear 68, the torque limiter (fitting portion 69), the small idle gear 67, and the free wheel gear 36. Is transmitted to the starting gear 23 on the outer periphery of the crank web via the one-way clutch 48 and the starting drive gear 35 to rotate the crankshaft 1. If the load on the crankshaft side is too large for some reason, the torque limiter of the large idle gear 68 operates and the starting force is cut off.

After the start is completed, the starting gear train 29
Only the starting drive gear 35 idles with the crankshaft 1 at all times, and the remaining gears 36, 67, 68 are stopped. That is, since only the starting drive gear 35 closest to the crankshaft in the starting system gear train 29 is always idle, the needle bearing 53 is interposed only in the starting drive gear 35 and the other gear 36 , 67, 68 are sufficient for direct fitting.

The lubricating action of the starting drive gear 35 and the one-way clutch 48, which are always idle, will be described. The lubricating oil pumped from a lubricating oil pump (not shown) to the lubricating oil supply passage 46 in FIG. Oil passages 44 and 61 in 31
Is supplied to the needle bearing 53 through the gap d1 between the oil groove 59 at the tip of the boss portion and the outer peripheral surface of the boss portion and the inner peripheral surface of the inner ring.
And the gap d2 at the tip of the inner ring, and is supplied to the sprag 60 portion.

[0026]

[Other Embodiments] (1) In the case where only claim 1 or 2 is applied, it is not always necessary to use the starting gear also as the balancer driving gear, and the present invention can be applied to an engine without a balancer. When only claim 1 is applied, it can be used also as a primary gear for driving wheels.

(2) It is also possible to use a large idle gear having no torque limiter.

(3) The present invention is not limited to a four-cylinder engine but can be applied to various multi-cylinder engines.

(4) As the cam member of the one-way clutch according to the fourth to sixth aspects, a member utilizing various sprags such as a parallelogram, a dwarf type or a triangular shape can be applied.

[0030]

As described above, according to the present invention, (1) the starting gear 23 is formed by directly cutting the outer peripheral surface of the crank web 8-6 of the crankshaft 1, and the starting gear 23 is formed. 23 is engaged with the starting drive gear 35 of the starting system gear train 29 connected to the starting motor 33, so that it is not necessary to secure a space for mounting a one-way clutch, a free wheel gear, and the like on the crankshaft. That is, the engine width can be reduced, and an increase in the crankshaft weight can be prevented. In particular, in a motorcycle, a wide bank angle can be ensured by reducing the engine width.

(2) The starting gear 23 is different from the primary gear 20 for driving the wheels, so that the starting gear 2
3, the degree of freedom in selecting the axial position can be increased, the space in the crankcase can be effectively used, and the assemblability of the starting gear train 29 can be improved.

(3) By using the starting gear 23 also as the balancer driving gear, the number of parts can be saved, and the compactness of the crankshaft width can be further improved.

(4) As described in the second aspect of the present invention, the starting drive gear train 29 is provided on the first and second support shafts 31 and 32 for starting provided in parallel with the crankshaft 1. Gear 35, one-way clutch 48, freewheel gear 3
6, when the idle small gear 67 and the idle large gear 68 are provided, the crankshaft width, that is, the crankshaft width, that is, the structure in which a free wheel gear and a one-way clutch are provided on the crankshaft as in the conventional Japanese Utility Model No. 2-18284 The engine width can be reduced.

(5) A one-way clutch 48 is arranged between the starting drive gear 35 closest to the crankshaft and the free wheel gear 36 adjacent thereto in the starting system gear train,
Since only the starting drive gear 35 is always idle, and the remaining gears 36, 67, and 68 rotate only at the time of starting, only the starting drive gear 35 is provided with a needle bearing 53 or a bearing metal. With bearings interposed,
Forcibly lubricating is sufficient, and the remaining gears 36, 67, 68 do not require bearings, and need only be fitted directly to the support shafts 31, 32. That is, the number of parts can be saved and the structure can be simplified.

(6) As in the third aspect of the present invention, the first support shaft 31 is disposed above and behind the crankshaft 1, and the second support shaft 32 is disposed above and behind the first support shaft 31. By engaging the output gear 34 of the starting motor 33 with the front end of the large idle gear 68 on the second support shaft, the length of the starting system gear train 29 in the front-rear direction can be made compact in the front half of the crankcase. As a result, a large rear space of the crankcase 2 can be secured. Thereby, for example, as shown in FIG. 3, a sufficient volume of the breather chamber 17 formed at the rear of the upper surface of the crankcase 2 can be ensured, and a wide space for the transmission gear is provided in the transmission gear chamber 75 behind the crankshaft. An arrangement space can be easily secured.

(7) By disposing the relatively heavy starting motor 33 in front of the second support shaft 32, when the center of gravity of the starting motor 33 approaches the center of gravity of the vehicle, the load on the front wheels of the motorcycle can be increased. Can be.

(8) Each of the gears 35 and 3 of the starting system gear train 29
First, second support shafts 31, 3 for supporting 6, 67, 68
2 is supported on the upper case member 2a of the crankcase 2 and the starting motor 33 is attached to the upper wall of the upper case member 2a, so that the entire starting device can be assembled when the upper case member 2a is assembled. Engine assemblability is improved.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a four-cylinder engine for a motorcycle to which the present invention is applied (II-II cross-sectional schematic view of FIG. 3).

FIG. 2 is an enlarged development view taken along the line II-II of FIG. 3;

FIG. 3 is a sectional view taken along the line III-III of FIG. 2;

FIG. 4 is a longitudinal sectional view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crankshaft 2 Crankcase 2a Upper case member 2b Lower case member 3 Cylinders 8-1,..., 8-8 Crankweb 20 Primary gear for driving wheels 23 Starting gear (also used as balancer driving gear) 26 Balancer gear 29 Starting system gear Row 31 First support shaft 32 Second support shaft 33 Start motor 34 Output gear 35 Start drive gear 36 Free wheel gear 44, 61 Oil passage 48 One-way clutch 50 Start drive gear boss 52 Outer ring 53 Needle bearing 55 Boss portion of free wheel gear 56 Inner ring 60 Sprag (cam member) 67 Small idle gear 68 Large idle gear

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F02N 15/02

Claims (4)

(57) [Claims] 1. A primary gear 20 connected to a gear mechanism for driving wheels is formed on a crankshaft 1, and separate from the primary gear 20 directly on an outer peripheral surface of a crank web 8 of the crankshaft 1. To form a starting gear 23, which meshes with a starting drive gear 35 of a starting system gear train 29 connected to a starting motor 33,
A starter for a vehicle engine, wherein the starter also meshes with a balancer gear 26 of a balancer shaft 25 as a balancer drive gear. 2. A primary gear 20 connected to a gear mechanism for driving wheels is formed on the crankshaft 1, and a starting gear 23 is provided on the crankshaft 1 separately from the primary gear 20. First and second support shafts 3 for starting
1 and 32, a starting drive gear 35 meshing with the starting gear 23 on the first support shaft 31 as a starting system gear train 29 connected from the starting gear 23 to the starting motor 33; A free wheel gear 36 connected to the drive gear 35 via a one-way clutch 48 is arranged. On the second support shaft 32, an idle small gear 67 meshing with the free wheel gear 36, and an idle small gear 67
And a large idle gear 68 which rotates integrally with the output gear 34 of the start motor 33 and is arranged. 3. The crankcase 2 accommodates a crankshaft in a front portion thereof, and a transmission gear chamber 75 behind the crankshaft accommodating portion.
The first support shaft 31 is disposed above and behind the crankshaft 1, the second support shaft 32 is disposed above and behind the first support shaft 31, and the starting motor 33 is connected to the second support shaft. 3. The starting device for a vehicle engine according to claim 2, wherein the starting device is disposed forward of the vehicle. 4. The vehicle according to claim 2, wherein the first and second support shafts and the starting motor are supported by an upper case member of a vertically divided crankcase. Engine starting device.