JPH0447421Y2 - - Google Patents

Description

[Detailed Description of the Invention] A. Purpose of the Invention (1) Field of Industrial Application This invention relates to an engine kick-starting device used in motorcycles and the like, and in particular to an improvement to a kick-starting device consisting of a starting shaft arranged so as to be able to move back and forth and to rotate freely relative to the crankshaft, a kick shaft arranged parallel to the starting shaft and rotated by a kick pedal, a helical-type drive gear fixed to the kick shaft, a helical-type driven gear fixed to the starting shaft and meshing with the drive gear, which receives forward thrust towards the crankshaft when driven by the drive gear due to the kick operation of the kick pedal, and drive and driven clutch bodies which are arranged on the starting shaft and the crankshaft, respectively, and which engage with each other as the starting shaft advances towards the crankshaft.

(2) Prior Art Such a starting device is already known, as described in, for example, Japanese Utility Model Application Publication No. 60-34563.

(3) Problems to be solved by the invention In the conventional starting device, if the engine does not start even when the kick pedal is pressed and the crankshaft does not have enough surplus power to overcome top dead center, the ignition timing In some cases, the pressure of the explosive gas may cause the crankshaft to rotate in reverse, placing an excessive load on various parts of the starter.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide the above-mentioned kick-type starting device that does not receive excessive load even if the crankshaft is reversed due to the above-mentioned starting error. .

B. Structure of the invention (1) Means for solving the problem In order to achieve the above object, the present invention has a driving clutch body fitted to a driven gear so as to be able to rotate freely within a certain range, and The present invention is characterized in that an elastic member is interposed between the body and the starting shaft to spring the driving clutch body in the direction of detachment from the driven clutch body.

(2) Effect When the driven gear is driven from the drive gear by the kick operation of the kick pedal to start the engine, the thrust generated in the meshing portion of both gears causes the drive clutch body to move forward and engage the driven clutch body. The rotational torque of the driven gear is transmitted to the crankshaft via both clutch bodies to crank it. At this time, the thrust generated at the threaded portion of the driven gear and the drive clutch body causes a relative displacement in the axial direction between the drive clutch body and the starting shaft, and elastic deformation is imparted to the elastic member.

When the engine does not start even with such a kick operation and reverse torque is generated on the crankshaft, the reverse torque tries to be transmitted to the starting shaft via both clutch bodies in an engaged state. At this time, if the axial sliding resistance between the driving and driven gears is greater than the axial sliding resistance between the driving and driven clutch bodies, the repulsive force of the elastic member that has been deformed first will cause the driving clutch body to move against the driven clutch. By separating the engine from the body, it is possible to cut off transmission of the reverse rotation torque of the crankshaft to the starting shaft. In addition, if the axial sliding resistance between both gears is smaller than the axial sliding resistance between both clutch bodies, the thrust generated at the threaded portion of the driving clutch body and driven gear will cause the elastic member to further deform. By retracting the shaft, it is possible to absorb the reverse rotation torque of the crankshaft and reduce the transmission to the starting shaft side.

(3) Embodiment An embodiment in which the present invention is applied to a starting device for a motorcycle engine will be described below with reference to the drawings. A starting shaft 4 rotatably and slidably supported by a side cover 3 joined to one side is arranged coaxially with the end faces facing each other, and a kick shaft 5 rotates in parallel to the side cover 3. Supported freely.

A kick pedal 6 is fixed to the kick shaft 5 on the outside of the side cover 3, and a large-diameter sector-shaped drive gear 7 is fixed on the inside of the side cover 3. Further, a torsion coil type return spring 8 is connected to the kick shaft 5 for biasing the kick pedal 6 toward its rest position. The rest position of the kick pedal 6 is regulated by one end surface of the drive gear 7 coming into contact with a stopper 9 protruding from the inner wall of the side cover 3, and its tightening limit is determined by the contact of the other end surface of the drive gear 7 with a coaxial stopper 9. It is regulated by coming into contact with.

A small-diameter, wide-width driven gear 10 that meshes with the drive gear 7 is formed on the starting shaft 4 . These gears 7, 10 are connected to the kick pedal 6 in the direction of the arrow in FIG.
The drive gear 7 is arranged so that the driven gear 10 is driven in the normal rotational direction of the crankshaft 1 when the crankshaft 1 is operated, and the drive gear 7 applies a thrust to the driven gear 10 toward the crankshaft 2 during the above operation. It is formed into a helical shape to give

A boss 11a of a cup-shaped drive latch 11 serving as a drive clutch body is fitted into the driven gear 7 at its end on the crankshaft 2 side so as to be able to rotate freely. One end of the starting shaft 4 protrudes into the body 11b of the drive ratchet 11, and is provided with a flange 4a at its tip.
and the boss 11b of the drive ratchet 11,
An annular elastic member 17 made of rubber, and this elastic member 17
A flat washer 18 is interposed to avoid contact with the boss 11a. In order to restrict the drive ratchet 11 from sliding on the driven gear 10 to the side opposite to the crankshaft 2, a stop ring 19 is provided on the driven gear 10.
is locked.

A driven latch 12 facing the drive latch 11 is fixed to the crankshaft 2, and these latches 11 and 12 constitute a starting clutch 13. The teeth of these ratchets 11 and 12 move from the driving ratchet 11 to the driven ratchet 1 in the normal rotational direction of the crankshaft 2 when both are engaged.
2 can be driven, but when the driven ratchet 12 attempts to drive the driving ratchet 11, the driven ratchet 12 is formed so as to exert a repelling force on each other.

An annular groove 14 is formed on the outer periphery of the starting shaft 4, and a pinch spring 15 is frictionally engaged with this groove 14. The base end of this pinch spring 15 is connected to the side cover 3
It is slidably engaged with a support shaft 16 parallel to the starting shaft 4, which is protruding from the inner wall. Therefore, the pinch spring 15 provides a predetermined rotational resistance to the drive latch 11 while allowing axial movement together with the drive latch 11.

Next, the operation of this embodiment will be explained.

Now, when the kick shaft 5 is rotated in the direction of the arrow in FIG. 2 by a kick operation of the kick pedal 6 to start the engine, the drive gear 7 is simultaneously rotated to drive the driven gear 10. Then, since the driven gear 10 and the driving ratchet 11 integrated with the starting shaft 4 are receiving rotational resistance from the pinch spring 15, the starting shaft 4 is first cranked by the forward thrust generated at the meshing portion of the helical gears 7 and 10. It moves forward toward the shaft 2 and engages the driving latch 11 with the driven latch 12, that is, puts the starting clutch 13 in the connected state. After that, the pinch spring 15 and the drive ratchet 11
Since the driving gear 7 rotationally drives the driven gear 10 while causing slippage between the driving gear 7 and the driven gear 10, the rotational force of the gear 10 is transmitted to the crankshaft 2 via the connected starting clutch 13, and the crankshaft 2 be done.

At that time, driven gear 10 and drive ratchet 11
The thrust generated at the threaded portion of the starter shaft 4 causes the starter shaft 4 to retreat to the opposite side of the crankshaft 2, and the elastic member 17 is compressively deformed between the flange 4a and the boss 11a of the drive ratchet 11 in accordance with the amount of retreat. Become.

By the way, when the engine does not start even with such a kick operation and reverse torque is generated on the crankshaft 2, the reverse torque tries to be transmitted to the starter shaft 4 via the starter clutch 13 which is in a connected state.

At this time, if the axial sliding resistance between the two gears 7 and 10 is greater than the axial sliding resistance between the two latches 11 and 12, the repulsive force of the elastic member 17 that has previously undergone compression deformation causes the drive ratchet 11 to is disengaged from the driven ratchet 12, so that the transmission of the reversal torque to the starting side 4 can be interrupted.

In addition, if the axial sliding resistance between both gears 7 and 10 is smaller than the axial sliding resistance between both ratchets 11 and 12, driving ratchet 11 and driven gear 10
The thrust generated at the threaded portion causes the starting shaft 4 to move further backward, and further compressive deformation is applied to the elastic member 17, thereby making it possible to absorb the above-mentioned reverse rotation torque.

When the engine is started, the driven latch 12, which is integral with the crankshaft 2, rotates at a faster speed than the drive latch 11, so it pushes back the drive latch 11 and disengages it, so that the rotation of the crankshaft 2 starts. It is not transmitted to the shaft 4.

After starting, when the kick pedal 6 is released, the drive gear 7 is reversed by the force of the return spring 8, so the driven gear 10 is moved to the starting shaft 4 by the opposite action to that during the starting operation.
As a result, the drive latch 11 can be completely separated from the driven latch 12.

C. Effects of the invention As described above, according to the invention, the drive clutch body is fitted to the driven gear so as to be able to rotate freely within a certain range, and the drive clutch body is connected to the driven gear between the drive clutch body and the starting shaft. An elastic member that springs in the direction of separation from the body is inserted, so even if the crankshaft is reversed due to a mistake in starting the engine during a hard operation, the driven gear, drive clutch body, and elastic member work together to prevent the drive clutch body from moving. By disengaging from the driven clutch body or absorbing reverse torque, it is possible to prevent generation of excessive load due to reverse torque, contributing to weight reduction and improved durability of the starter device.

Moreover, since the helical type driven gear into which the drive clutch body is screwed functions as a quick screw, there is no need to specially form a quick screw on the starting shaft, and the structure is simple.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a longitudinal sectional plan view of a kick-type starting device for a motorcycle engine, and FIG. 2 is a sectional view taken along the line taken in FIG. 1. 2...Crankshaft, 4...Starting shaft, 5...Kick shaft, 6...Kick pedal, 7...Drive gear, 1
0... Driven gear, 11... Drive ratchet as drive clutch body, 12... Driven ratchet as driven clutch body, 13... Driven clutch, 1
7...Elastic member.

Claims (1)

[Scope of utility model registration request] A starting shaft that is movable forward and backward with respect to the crankshaft and rotatable, a kick shaft that is arranged parallel to the starting shaft and rotated by a kick pedal, and a helical drive gear that is fixed to the kick shaft. and a helical driven gear that is fixedly installed on the starting shaft and meshes with the driving gear and receives forward thrust toward the crankshaft due to the drive from the driving gear when the kick pedal is operated. In the engine kick-type starting device, which consists of a driving and driven clutch body that engage with each other as the starting shaft advances toward the crankshaft side, the driving clutch body is fitted to the driven gear so as to be able to rotate freely within a certain range. A kick-type starting device for an engine, characterized in that an elastic member is interposed between the drive clutch body and the starting shaft to spring the drive clutch body in the direction of separation from the driven clutch body.