Transmission

Patent metadata

Field	Value
Publication number	US-9528571-B2
Application number	US-201514679750-A
Country	US
Kind code	B2
Filing date	Apr 6, 2015
Priority date	Apr 9, 2014
Publication date	Dec 27, 2016
Grant date	Dec 27, 2016

Abstract

If a sleeve of a double cone-type synchronizer is not smoothly engaged with a dog gear because of getting caught by the dog gear, the dog gear, as pressed by the sleeve, may lean with a spline-connecting part of the dog gear to a transmission gear as a fulcrum, so that an inner ring of a blocking ring may be damaged by being squeezed between the dog gear and a hub. However, the transmission gear includes: a tooth surface portion having tooth surfaces formed on one axial end side of the transmission gear; and a contact portion formed on the opposite axial end side, and abutting against the dog gear. The contact portion extends radially outward of a through-hole of the dog gear, thereby preventing the dog gear, as pressed by the sleeve, from leaning toward the transmission gear so as to prevent damage of the inner ring.

First claim

What is claimed is:

1. A transmission comprising a synchronizer capable of connecting together a hub connected to a rotary shaft, and a dog gear relatively unrotatably spline-connected to a transmission gear which is relatively rotatably supported on the rotary shaft, wherein:
the synchronizer includes:
a sleeve spline-connected to the hub so as to be relatively unrotatable, and slidable in an axial direction, and
a blocking ring disposed between the hub and the dog gear, and enabling the hub and the dog gear to frictionally engage with each other in response to movement of the sleeve,

the blocking ring includes:
an outer ring disposed on an outer side of the blocking ring in a radial direction, having dog teeth meshable with the sleeve in an outer periphery of the outer ring, and engaged with the hub so as to be relatively rotatable by a predetermined angle,
an inner ring disposed on an inner side of the blocking ring in the radial direction, and engaged with the hub so as to be relatively rotatable by a predetermined angle, and
an intermediate ring disposed between the outer ring and the inner ring in the radial direction, and being in slide contact with an inner peripheral surface of the outer ring and an outer peripheral surface of the inner ring,

wherein the dog gear includes a recessed portion engaged with a protrusion of the intermediate ring,
said inner ring having an upper surface extending in said axial direction and facing towards a lower surface of said intermediate ring, a lower surface extending in said axial direction and facing towards said rotary shaft, a perimeter end surface extending between said upper and lower surfaces of said inner ring transverse to said axial direction, and an interior end surface extending between said upper and lower surfaces of said inner ring transverse to said axial direction and facing said hub, wherein said dog gear contacts said inner ring at only said perimeter end surface of said inner ring,
the transmission gear includes
a tooth surface portion formed on one axial end side of the transmission gear, and having tooth surfaces; and
a contact portion formed on an opposite axial end side of the transmission gear, and being in contact with the dog gear, and

the contact portion extends outward of the recessed portion in the radial direction.

2. The transmission according to claim 1 ,
wherein the recessed portion of the dog gear is a through-hole penetrating through the dog gear in the axial direction.

3. The transmission according to claim 1 , further comprising:
a first input shaft, a second input shaft and an output shaft disposed in parallel to one another;
a first clutch and a second clutch which selectively transmit driving force of a driving source to any of the first input shaft and the second input shaft;
a plurality of input gears supported relatively rotatably on the first and second input shafts;
a plurality of output gears fixedly provided to the output shaft, and meshing with the plurality of input gears;
a first synchronizer capable of connecting the first input shaft to a first input gear which is one of the plurality of input gears supported on the first input shaft; and
a second synchronizer capable of connecting the second input shaft to a second input gear which is one of the plurality of input gears supported on the second input shaft, wherein
the first input gear meshes with a first output gear which is one of the plurality of output gears,
the second input gear meshes with a second output gear which is another of the plurality of output gears,
the rotary shaft is the first input shaft,
the transmission gear is the first input gear,
the synchronizer is the first synchronizer, and
an outer peripheral portion of the second output gear is opposite to an outer peripheral portion of a cylindrical portion of the transmission gear which is formed between the tooth surface portion and the contact portion of the transmission gear and which is smaller in diameter than the tooth surface portion and the contact portion.

4. The transmission according to claim 1 , wherein said perimeter end surface of said inner ring includes a plurality of cutouts, whereby the pressing load from the dog gear against said perimeter end surface of said inner ring is transmitted to said inner ring at opposite sides of said cut outs such as to inhibit damage to said inner ring due to deformation.

5. The transmission according to claim 1 , wherein
the hub includes a plurality of recessed portions spaced out in a peripheral direction,
the inner ring includes
a plurality of protrusions fitted in the recessed portions of the hub, and
a plurality of cutouts formed in an end surface of the inner ring on a dog gear side at positions corresponding to the plurality of recessed portions of the hub.

6. The transmission according to claim 5 ,
wherein the recessed portion of the dog gear is a through-hole penetrating through the dog gear in the axial direction.

7. The transmission according to claim 5 , further comprising:
a first input shaft, a second input shaft and an output shaft disposed in parallel to one another;
a first clutch and a second clutch which selectively transmit driving force of a driving source to any of the first input shaft and the second input shaft;
a plurality of input gears supported relatively rotatably on the first and second input shafts;
a plurality of output gears fixedly provided to the output shaft, and meshing with the plurality of input gears;
a first synchronizer capable of connecting the first input shaft to a first input gear which is one of the plurality of input gears supported on the first input shaft; and
a second synchronizer capable of connecting the second input shaft to a second input gear which is one of the plurality of input gears supported on the second input shaft, wherein
the first input gear meshes with a first output gear which is one of the plurality of output gears,
the second input gear meshes with a second output gear which is another of the plurality
of output gears,
the rotary shaft is the first input shaft,
the transmission gear is the first input gear,
the synchronizer is the first synchronizer, and
an outer peripheral portion of the second output gear is opposite to an outer peripheral portion of a cylindrical portion of the transmission gear which is formed between the tooth surface portion and the contact portion of the transmission gear and which is smaller in diameter than the tooth surface portion and the contact portion.

Assignees

• Honda Motor Co Ltd

Inventors

• Kumagai Nobuhiro
• Kamo Shunji
• Sakurai Kazuki

Classifications

• F16D2023/0681

  Double cone synchromesh clutches · CPC title

• F16D23/025

  Synchro rings · CPC title

• F16H3/006

  power being selectively transmitted by parallel flow paths, e.g. dual clutch transmissions · CPC title

• F16H3/08 Primary

  exclusively or essentially with continuously meshing gears, that can be disengaged from their shafts · CPC title

• F16D23/06 Primary

  and a blocking mechanism preventing the engagement of the main clutch prior to synchronisation · CPC title