Transmission apparatus for saddle-type vehicle

Patent metadata

Field	Value
Publication number	US-10935108-B2
Application number	US-201715714027-A
Country	US
Kind code	B2
Filing date	Sep 25, 2017
Priority date	Sep 29, 2016
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

In a transmission apparatus for a saddle-type vehicle, dowels on first transmission gears are engageable in and disengageable from dowel holes in adjacent second transmission gears to shift gear positions. The first transmission gears are slidable in response to angular movement of a shift spindle caused by operating a shift pedal. Invalid engagement time, during which the dowels and dowel columns are in sliding abutment, at an idling engine rotational speed is in the range from 0 msec. to 40 msec., providing an enhanced feeling for gear shifting operations and reduce hammering noise.

First claim

The invention claimed is:

1. A transmission apparatus for a saddle-type vehicle, comprising:
first transmission gears supported on support shafts so as to be circumferentially non-rotatable and axially slidable with respect to said support shafts; and
second transmission gears supported on said support shafts adjacent to said first transmission gears so as to be circumferentially rotatable and axially non-slidable with respect to said support shafts;
said first transmission gears having dowels projecting axially;
said second transmission gears having dowel holes defined axially concavely therein and dowel columns defining said dowel holes;
said dowels being engageable in and disengageable from said dowel holes to shift gear positions;
said first transmission gears being slidable in response to angular movement of a shift spindle caused by operating a shift pedal;
wherein a length from a pitch circle of said dowels and said dowel columns to dowel tip ends of said dowels is smaller than a length from the pitch circle of said dowels and said dowel columns to dowel base ends of said dowels; and
a length from the pitch circle of said dowels and said dowel columns to dowel column tip ends of said dowel columns is smaller than a length from the pitch circle of said dowels and said dowel columns to dowel column base ends of said dowel columns.

2. The transmission apparatus for a saddle-type vehicle according to claim 1 , wherein an invalid engagement time during which facing wall surfaces of said dowels and facing wall surfaces of said dowel columns abut and slide against each other at an idling engine rotational speed is in the range from 0 millisecond to a value below 40 millisecond.

3. The transmission apparatus for a saddle-type vehicle according to claim 1 , wherein an invalid engagement time during which facing wall surfaces of said dowels and facing wall surfaces of said dowel columns abut and slide against each other at an idling engine rotational speed is in the range from 0 millisecond to a value below 40 millisecond.

4. The transmission apparatus for a saddle-type vehicle according to claim 1 , wherein a dowel nipping angle between line segments extending from the center of rotation of the transmission gears through abutment points on both sides of said dowels where said dowels and said dowel columns abut against each other is in the range from 6 degrees to 9 degrees; and
a dowel column nipping angle between line segments extending from the center of rotation of the transmission gears through abutment points on both sides of said dowel columns where said dowel columns and said dowels abut against each other is in the range from 6 degrees to 9 degrees.

5. The transmission apparatus for a saddle-type vehicle according to claim 1 , wherein a backlash angle between said dowels and said dowel columns is in the range from 0 degree to 15 degrees.

6. The transmission apparatus for a saddle-type vehicle according to claim 1 , wherein said dowels include inner circumferential stiffener rings and dowel back plates; and
said dowel columns include outer circumferential stiffener rings and dowel column back plates.

7. The transmission apparatus for a saddle-type vehicle according to claim 1 , wherein said dowels have abutment surfaces for abutment against said dowel columns, the abutment surfaces being spread from line segments extending from the center of rotation of the transmission gears through abutment points between said dowels and said dowel columns by a dowel spreading angle; and
said dowel columns have abutment surfaces for abutment against said dowels, the abutment surfaces being spread from line segments extending from the center of rotation of the transmission gears through abutment points between said dowels and said dowel columns by a dowel column spreading angle.

8. A transmission apparatus for a saddle-type vehicle, comprising:
first transmission gears supported on support shafts so as to be circumferentially non-rotatable and axially slidable with respect to said support shafts; and
second transmission gears supported on said support shafts adjacent to said first transmission gears so as to be circumferentially rotatable and axially non-slidable with respect to said support shafts;
said first transmission gears having dowels projecting axially;
said second transmission gears having dowel holes defined axially concavely therein and dowel columns defining said dowel holes;
said dowels being engageable in and disengageable from said dowel holes to shift gear positions;
said first transmission gears being slidable in response to angular movement of a shift spindle caused by operating a shift pedal;
wherein said dowels have abutment surfaces for abutment against said dowel columns, the abutment surfaces being spread from line segments extending from the center of rotation of the transmission gears through abutment points between said dowels and said dowel columns by a dowel spreading angle;
said dowel columns have abutment surfaces for abutment against said dowels, the abutment surfaces being spread from line segments extending from the center of rotation of the transmission gears through abutment points between said dowels and said dowel columns by a dowel column spreading angle; and
wherein of the abutment surfaces of said dowels and said dowel columns which abut against each other, the abutment surfaces of either said dowels or said dowel columns are straight whereas the surfaces of the other are curved as viewed along the axis of rotation of the transmission gears.

9. A transmission apparatus for a saddle-type vehicle, comprising:
first transmission gears supported on support shafts so as to be circumferentially non-rotatable and axially slidable with respect to said support shafts; and
second transmission gears supported on said support shafts adjacent to said first transmission gears so as to be circumferentially rotatable and axially non-slidable with respect to said support shafts;
said first transmission gears having dowels projecting axially;
said second transmission gears having dowel holes defined axially concavely therein and dowel columns defining said dowel holes;
said dowels being engageable in and disengageable from said dowel holes to shift gear positions;
said first transmission gears being slidable in response to angular movement of a shift spindle caused by operating a shift pedal;
wherein said dowels have abutment surfaces for abutment against said dowel columns, the abutment surfaces being spread from line segments extending from the center of rotation of the transmission gears through abutment points between said dowels and said dowel columns by a dowel spreading angle; and
said dowel columns have abutment surfaces for abutment against said dowels, the abutment surfaces being spread from line segments extending from the center of rotation of the transmission gears through abutment points between said dowels and said dowel columns by a dowel column spreading angle;
wherein inflection points on said dowel columns between curved surfaces of dowel column base ends of said dowel columns and the abutment surfaces thereof are positioned radially outwardly of inflection points on said dowels between curved surfaces of dowel tip ends of said dowels and the abutment surfaces thereof; and
the inflection points on said dowels between curved surfaces of dowel base ends of said dowels and the abutment surfaces thereof are positioned radially inwardly of inflection points on said dowel columns between curved surfaces of dowel column tip ends of said dowel columns and abutment surfaces thereof.

Assignees

• Honda Motor Co Ltd

Inventors

• Kittaka Eiji
• Kudo Takashi

Classifications

• F16H2057/0203

  the gearbox is associated or combined with a crank case of an engine · CPC title

• F16H2057/02065

  for motorcycles or squads · CPC title

• F16H2200/0043

  the gear ratios comprising four forward speeds · CPC title

• F16H57/0006

  Vibration-damping or noise reducing means specially adapted for gearings (devices for varying tension of belts, ropes or chains with damping means F16H7/0829; toothed members with construction providing vibration damping F16H55/14; reducing vibrations or noise of the gearbox casing F16H57/028; suppression of vibrations or noise of gear selectors F16H59/0208; control of hydrostatic fluid gearing preventing or reducing vibrations or noise F16H61/4183) · CPC title

• B60Y2200/12

  Motorcycles, Trikes; Quads; Scooters · CPC title