Power transmission unit

Patent metadata

Field	Value
Publication number	US-11242914-B2
Application number	US-202017136719-A
Country	US
Kind code	B2
Filing date	Dec 29, 2020
Priority date	Jan 22, 2020
Publication date	Feb 8, 2022
Grant date	Feb 8, 2022

Abstract

A power transmission unit that can prevent unintentional disengagement of a clutch. A first set of teeth formed on an outer circumferential surface of a first rotary member is engaged with a third set of teeth formed on an inner circumferential surface of a second rotary member. A second set of teeth formed on an inner circumferential surface of the first rotary member is meshed with a fourth set of teeth formed on an outer circumferential surface of a third rotary member. A center of engagement between the first set of teeth and the third set of teeth is situated at a point withdrawn from a center of engagement between the second set of teeth and the fourth set of teeth in the direction to disengage the first set of teeth from the third set of teeth.

First claim

What is claimed is:

1. A power transmission unit comprising:
a cylindrical first rotary member;
a cylindrical second rotary member that is diametrically larger than the first rotary member, and that is arranged concentrically with the first rotary member;
a cylindrical third rotary member that is diametrically smaller than the first rotary member, and that is arranged concentrically with the first rotary member;
a first engagement device including the second rotary member;
a first set of teeth that is formed on an outer circumferential surface of the first rotary member;
a second set of teeth that is formed on an inner circumferential surface of the first rotary member;
a third set of teeth that is formed on an inner circumferential surface of the second rotary member to be meshed with the first set of teeth; and
a fourth set of teeth that is formed on an outer circumferential surface of the third rotary member to be meshed with the second set of teeth;
wherein the first rotary member is reciprocated in an axial direction to engage and disengage the first set of teeth to/from the third set of teeth thereby engaging and disengaging the first engagement device, and
a center of engagement between the first set of teeth and the third set of teeth is situated at a point withdrawn from a center of engagement between the second set of teeth and the fourth set of teeth in a direction to disengage the first set of teeth from the third set of teeth.

2. The power transmission unit as claimed in claim 1 , wherein the second rotary member is connected to a fourth rotary member mounted on a shaft other than a shaft of the second rotary member in a torque transmittable manner.

3. The power transmission unit as claimed in claim 1 , wherein the second rotary member is rotatably supported by a bearing interposed between a casing of the power transmission unit and the second rotary member.

4. The power transmission unit as claimed in claim 1 ,
wherein the first rotary member includes a pushing member expanding from one end of the first rotary member, and
the first set of teeth is engaged with the third set of teeth by pushing the first rotary member by the pushing member.

5. The power transmission unit as claimed in claim 1 , wherein the first rotary member and the third rotary member are always engaged with each other to rotate integrally.

6. The power transmission unit as claimed in claim 1 ,
wherein a prime mover of the power transmission unit comprises an engine, a first motor, and a second motor,
the power transmission unit further comprises:
a first differential mechanism that performs a differential action among a first rotary element that is connected to the engine, a second rotary element that is connected to the first motor, and a third rotary element that delivers torque to drive wheels; and
a second differential mechanism that performs a differential action among a fourth rotary element that is connected to the second motor, a fifth rotary element that is connected to the third rotary element, and a sixth rotary element,

the second rotary member is rotated integrally with the fourth rotary element,
the third rotary member is rotated integrally with the sixth rotary element, and
the first engagement device selectively connects the fourth rotary element to the sixth rotary element.

7. The power transmission unit as claimed in claim 6 , further comprising:
an input member;
an output member that outputs torque delivered from the input member; and
a second engagement device that selectively connects the sixth rotary element to the first rotary element,
the first engagement device is engaged to establish a first continuously variable mode in which a speed ratio between the input member and the output member can be varied continuously, and
the second engagement device is engaged to establish a second continuously variable mode in which a speed ratio between the input member and the output member can be varied continuously, and in which a torque amplification factor is different from the first continuously variable mode.

Assignees

• Toyota Motor Co Ltd

Inventors

• Ebuchi Hiroaki
• Isami Yoichiro
• Yoshino Hirotsugu
• Yasui Hiroki

Classifications

• F16H2063/3093

  Final output elements, i.e. the final elements to establish gear ratio, e.g. coupling sleeves or other means establishing coupling to shaft · CPC title

• B60K6/387

  Actuated clutches, i.e. clutches engaged or disengaged by electric, hydraulic or mechanical actuating means · CPC title

• F16H3/76 Primary

  with an orbital gear having teeth formed or arranged for obtaining multiple gear ratios, e.g. nearly infinitely variable · CPC title

• F16H3/006 Primary

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

• B60K6/445

  Differential gearing distribution type · CPC title