US 8,127,635 B2 · Twin clutch transmission

Abstract

A twin clutch transmission for reducing the frequency of hit noise occurring in a dog clutch when shifting from neutral to a first speed. The twin clutch transmission includes a plurality of pairs of gears according to the number of speed stages between dual-structured main shafts and a countershaft. A twin clutch is disposed on the main shafts wherein a rotational drive force of an engine is transferred or blocked. A transmission between adjacent speed change gears on each shaft by a dog clutch occurs with a shift drum for switching between an engagement condition of the dog clutch by driving a shift fork. The patterns of guide grooves in the shift drum are formed wherein the dog clutches for a first speed gear and a second speed gear engage simultaneously when the shift drum is rotated by predetermined angles to shift from neutral to the first speed.

Drawings

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Drawings

Claims17

Dependent claims

A twin clutch transmission comprising:

a transmission having a plurality of pairs of gears corresponding to the number of speed stages between a main shaft and a countershaft;
and
a twin clutch disposed on the main shaft,
the twin clutch transmission being adapted to transfer or block a rotational drive force of an engine to/from the transmission by means of the twin clutch,
wherein the main shaft includes an inner main shaft and an outer main shaft rotatably supporting the inner main shaft;
the twin clutch includes a first clutch adapted to transfer or block rotation drive force to be transmitted to the inner main shaft, and a second clutch adapted to transfer or block the rotational drive force to be transmitted to the outer main shaft;
the transmission is configured to perform the transmission of the rotational drive force between adjacent speed change gears on each shaft by a dog clutch having a dog tooth and a dog recess;
the transmission is so configured that, when a dog clutch to transmit the rotational drive force with a first speed gear and a dog clutch to transmit rotation drive force with a second speed gear are both engaged, speed is changed between first speed and second speed by switching a connected condition of the twin clutch;
a shift drum is provided to switch an engagement condition of the dog clutch by driving a shift fork;
the shift fork is configured to be driven along a guide groove formed in a surface of the shift drum;
and
the pattern of the guide groove is formed so that, when the shift drum is rotated by predetermined angles to change speed from neutral to first speed, the dog clutch for the first speed gear and the dog clutch for the second speed gear simultaneously engage,
wherein the pair of gears comprises a slidable gear that is axially slidably mounted to select one pair of gears operable to transmit a rotary drive force to the countershaft, and a unslidable gear mounted axially unslidably;
the slidable gear is provided on each of the inner main shaft, the outer main shaft, and the countershaft;
the dog clutch is provided between the slidable gear and the unslidable gear adjacent to the slidable gear on the same shaft;
and
the rotational drive force is transferred or blocked between the slidable gear and the unslidable gear that are adjacent to each other on the same shaft by sliding the slidable gear by means of the shift fork.

14 more elements

A twin clutch transmission comprising:

a transmission having a plurality of pairs of gears corresponding to the number of speed stages between a main shaft and a countershaft;
and
a first clutch operatively positioned on an inner main shaft;
a second clutch operatively positioned on an outer main shaft;
the first and second clutches being adapted to transfer or block a rotational drive force of an engine to/from the transmission;
wherein the outer main shaft rotatably supports the inner main shaft;
the first clutch is adapted to transfer or block rotation drive force to be transmitted to the inner main shaft, and the second clutch is adapted to transfer or block the rotational drive force to be transmitted to the outer main shaft;
the transmission is configured to perform the transmission of the rotational drive force between adjacent speed change gears on each shaft by a dog clutch having a dog tooth and a dog recess;
wherein when a dog clutch transmitting the rotational drive force with a first speed gear and a dog clutch transmitting rotation drive force with a second speed gear are both engaged, speed is changed between first speed and second speed by switching a connected condition of the twin clutch;
a shift drum is operatively provided to switch an engagement condition of the dog clutch by driving a shift fork;
the shift fork is configured to be driven along a guide groove formed in a surface of the shift drum;
and
the pattern of the guide groove is formed so that, when the shift drum is rotated by predetermined angles to change speed from neutral to first speed, the dog clutch for the first speed gear and the dog clutch for the second speed gear simultaneously engage,
wherein the inner main shaft operatively connected to the first clutch supports the driving gears for odd-numbered speed stage gears,
wherein the first speed driving gear is integrally formed with the inner main shaft, the third speed gear is axially slidably and circumferentially unrotatably mounted relative to the inner main shaft and a fifth speed gear is axially unslidably and circumferentially rotatably mounted relative to the inner main shall.

12 more elements

A twin clutch transmission comprising:

a transmission having a plurality of pairs of gears corresponding to the number of speed stages between a main shaft and a countershaft;
and
a first clutch operatively positioned on an inner main shaft,
a second clutch operatively positioned on an outer main shaft;
the first and second clutches being adapted to transfer or block a rotational drive force of an engine to/from the transmission;
wherein the outer main shaft rotatably supports the inner main shaft;
the first clutch is adapted to transfer or block rotation drive force to be transmitted to the inner main shaft, and the second clutch is adapted to transfer or block the rotational drive force to be transmitted to the outer main shaft;
the transmission is configured to perform the transmission of the rotational drive force between adjacent speed change gears on each shaft by a dog clutch having a dog tooth and a dog recess;
wherein when a dog clutch transmitting the rotational drive force with a first speed gear and a dog clutch transmitting rotation drive force with a second speed gear are both engaged, speed is changed between first speed and second speed by switching a connected condition of the twin clutch;
a shift drum is operatively provided to switch an engagement condition of the dog clutch by driving a shift fork;
the shift fork is configured to be driven along a guide groove formed in a surface of the shift drum;
and
the pattern of the guide groove is formed so that, when the shift drum is rotated by predetermined angles to change speed from neutral to first speed, the dog clutch for the first speed gear and the dog clutch for the second speed gear simultaneously engage,
wherein the outer main shaft operatively connected to the second clutch supports the driving gears for even-numbered speed stage gears, and
wherein the second speed driving gear is integrally formed with the outer main shall, the fourth speed gear is axially slidably and circumferentially unrotatably mounted relative to the outer main shaft and a sixth speed gear is axially unslidably and circumferentially rotatably mounted relative to the outer main shaft.

12 more elements

Dependencies are inferred from the claim text.

Description5,426 words

Summary1,732 words

#The present application claims priority under 35 USC 119 to Japanese Patent Application No. 2008-021576 filed on Jan. 31, 2008 the entire contents of which are hereby incorporated by reference.

#1. Field of the Invention

#The present invention relates to a twin clutch transmission, and more specifically to a twin clutch transmission capable of reducing the frequency of hit noises occurring in a dog clutch when shifting from neutral to a first speed.

Brief description of the drawings5 figures

#The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:

#FIG. 1 is a sectional view of a twin clutch transmission according to one embodiment of the present invention;

#FIG. 2 is a skeleton diagram showing the positional relationship of speed change gears;

Detailed description3,567 words

#Preferred embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a sectional view of a twin clutch transmission 1 according to one embodiment of the present invention. FIG. 2 is a skeleton diagram showing the arrangement of speed change gears of the twin clutch transmission 1. The twin clutch transmission 1 comprises a twin clutch TCL composed of a first clutch CL1 and a second clutch CL2 and a forward six-stage sequential transmission TM, and is housed in a crankcase 2 together with an engine serving as a power source.

#A rotational drive force to be transmitted from a crankshaft (not shown) of the engine to a primary gear 3 having a shock absorbing mechanism 5 is output to a countershaft 9 equipped with a drive sprocket 10 through the twin clutch TCL, the outer main shaft 6 as an outer main spindle, the rotatably supported inner main shaft 7 as an inner main spindle, rotatable journaled to the outer main shaft, and six pairs of gears provided between the main shafts 6, 7 and the countershaft. Rotation drive force transmitted to the drive sprocket 10 is delivered to drive wheels (not shown) of a vehicle through a drive chain to be wound on the sprocket.

#The transmission TM has six pairs of gears between the main shafts and the countershaft, and it is possible to select which pair of gears to rotate in order to output the rotational drive force based on a combination of the position of a slidable gear axially slidably mounted on each shaft and the engagement/disengagement condition of the first clutch CL1 and the second clutch CL2. The twin clutch TCL is disposed within a clutch case 4 rotating integrally with the primary gear 3. The first clutch CL1 is unrotatably mounted on the inner main shaft 7 and the second clutch CL2 is unrotatably mounted on the outer main shaft 6. Between the clutch case 4 and each of the clutches CL1 and CL2, a clutch plate 12 is disposed that is composed of four clutch plates unrotatably supported by the clutch case 4 and four friction plates unrotatably supported by each of the clutches CL1 and CL2.

Facts

Application

12/351,968Filed 12 Jan 2009

Priority

JP 2008-02157631 Jan 2008

Published

US 2009/0193918 A16 Aug 2009

Granted

6 Mar 2012

Term ends

22 Jul 2030

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment, including 556 days of adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification7 codes

F16H 61/688
Without interruption of drive: with two inputs, e.g. selection of one of two torque-flow paths by clutches
F16H 63/18
The final output mechanisms being successively actuated by progressive movement of the final actuating mechanism: the final actuating mechanism…
F16H 61/32
With at least one movement of the final actuating mechanism being caused by a non-mechanical force, e.g. power-assisted: electric motors ,…
Y10T 74/19233
Interchangeably locked: plurality of counter shafts

Timeline

31 Jan 2008Priority claimedJP 2008-021576
12 Jan 2009Application filedUS 12/351,968
14 Jan 2009Assigned to Honda Motor Co., Ltd.assignment of assignor's interest
6 Aug 2009PublishedUS 2009/0193918 A1
6 Mar 2012GrantedUS 8,127,635 B2
12 Oct 2026TodayWithin its term
22 Jul 2030Term endsEstimated, includes 556 days of adjustment

Twin clutch transmission

Life of this patent

Twin clutch transmission

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims17

Description5,426 words

Drawings

Classification7 codes

Life of this patent

Description5,426 words