Clutch Back Torque Limiter Using Centrifugal Movement Restriction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In vehicles equipped with a clutch device featuring a cam for back torque limiter (slipper), engine starting by push starting can be unstable due to changes in clutch capacity.
Innovation Solution
A clutch device design that includes a slipper cam mechanism and a movement restricting mechanism, which uses centrifugal force to selectively restrict or allow axial movement of the clutch members, ensuring stable engine starting by managing back torque transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a cam for back torque limiter (slipper) is equipped in the clutch device, then back torque transmission is reduced, but clutch capacity changes causing unstable engine starting by push starting
Solution Approach 1:
The clutch capacity is made dynamically adjustable through the cam mechanism that axially moves the third clutch member based on rotational speed. At low speeds (below threshold), the movement restricting mechanism limits axial movement maintaining full clutch capacity for stable starting. At high speeds (above threshold), the cam allows axial movement reducing clutch capacity to limit back torque transmission.
Solution Approach 2:
The clutch capacity parameter is changed based on rotational speed conditions. The cam mechanism transforms rotational speed variations into axial position changes of the third clutch member, thereby changing the clutch capacity parameter from a fixed value to a variable value that adapts to operating conditions.
2Object-affected harmful factors
If the third clutch member is allowed to move axially to reduce back torque, then back torque transmission is limited, but clutch capacity changes affecting starting stability
Solution Approach 1:
The axial movement of the third clutch member is made dynamic and conditional rather than fixed. The movement restricting mechanism creates a threshold-based dynamic system where axial movement is permitted only when rotational speed exceeds the threshold, automatically adapting clutch capacity to operating conditions.
Solution Approach 2:
The centrifugal force generated by rotational speed acts as feedback to control the axial position of the third clutch member. When rotational speed increases, centrifugal force increases, automatically allowing axial movement to reduce clutch capacity and back torque transmission.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The clutch device stabilizes engine starting by reducing back torque and allowing smooth operation of the clutch disengagement process, even when equipped with a back torque limiter, through the use of a slipper cam mechanism and movement restricting mechanism.
Implementation Method 1
a movement restricting mechanism (40) provided to the third clutch member (13) which selectively limits movement of the third clutch member (13) in the clutch axial direction, wherein the movement restricting mechanism moves between movement restricting and non-restricting positions thereof by a centrifugal force generated by rotation of the third clutch member
Implementation Method 2
a slipper cam mechanism (30) provided between the second clutch member (12) and the third clutch member (13), and being configured such that in a state where a back torque is applied to the third clutch member (13) from the second clutch member (12), the slipper cam mechanism (30) moves the third clutch member (13) along with the pressurizing plate (15) in the clutch axial direction to reduce the back torque transmitted to the first clutch member (11)
Implementation Method 3
a clutch spring (16) which biases the pressurizing plate (15) to a pressure receiving plate (12d) side
Implementation Method 4
a first friction plate (14b) supported on the first clutch member (11) in an axially movable and integrally rotatable manner; a second friction plate (14c) supported on the third clutch member (13) in an axially movable and integrally rotatable manner, such that the second friction plate (14c) overlaps with the first friction plate (14b)
Data Source
AI summary
A clutch device includes a slipper cam mechanism which releases a back torque by moving a clutch center in an axial direction, and a plunger mechanism provided to the clutch center. The plunger mechanism engages with a movement restricting portion until a rotational speed of the clutch center reaches a threshold value thus restricting the movement of the clutch center in the clutch axial direction, and the plunger mechanism is operated by a centrifugal force when the rotational speed of the clutch center exceeds the threshold value such that it disengages from the movement restricting portion.