Controller of continuously variable transmission and vehicle provided with the same
First Claim
1. A controller of a continuously variable transmission (CVT) mounted on a vehicle, which includes an engine and an accelerator manipulating element manipulated by hand to control an accelerator, the controller includingan accelerator manipulated variable detector that detects a manipulated variable of the accelerator manipulating element, anda speed change ratio controller that sets a target speed change ratio of the CVT on the basis of the manipulated variable of the accelerator manipulating element and controls the CVT so that a current speed change ratio, that the CVT reaches, becomes the target speed change ratio, andwherein the speed change ratio controller comprisesa standard speed change ratio setting unit that sets a standard speed change ratio, according to a normal map, as the target speed change ratio so that V-N (vehicle speed-engine rotational frequency) characteristics prescribed by a vehicle speed and an engine rotational frequency fall in a predetermined region of speed change that has a top limit defined by V-N characteristics determined when the accelerator is fully opened to accelerate under a condition of a normal load and a lower limit defined by V-N characteristics determined when the accelerator is fully closed to decelerate under the condition of the normal load, when the manipulated variable of the accelerator manipulating element is in a predetermined standard range, the normal map being set so that the V-N characteristics do not get out of the predetermined region of speed change,a specific speed change ratio setting unit that corrects the standard speed change ratio and sets a corrected speed change ratio, which is outside the normal map, as the target speed change ratio so that the V-N characteristics get out of the predetermined region of speed change and the current speed change ratio, that the CVT reaches, becomes the target speed change ratio that gets the V-N characteristics out of the predetermined region of speed change so that the target speed change ratio is set without being restricted by the predetermined region of speed change, when the manipulated variable of the accelerator manipulating element exceeds the standard range, andan automatic return unit that, when the V-N characteristics get out of the predetermined region of speed change, resets the target speed change ratio so that the V-N characteristics having gotten out of the predetermined region of speed change return to the predetermined region of speed change and the current speed change ratio, that the CVT reaches, becomes the target speed change ratio that returns the V-N characteristics to the predetermined region of speed change.
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Accused Products
Abstract
A speed change ratio controller, which controls a speed change ratio of the continuously variable transmission, normally exercises map control according to a predetermined speed change ratio map so that a V-N characteristic curve prescribed by a vehicle speed (V) and an engine rotational frequency (N) falls in a range of a predetermined region of speed change. When an accelerator opening degree exceeds a predetermined range and a vehicle load exceeds a predetermined range a target speed change ratio is corrected so that the V-N characteristic curve gets out of the predetermined region of speed change. After the V-N characteristic curve gets out of the region of speed change, the necessity of continuation of acceleration or deceleration is determined on the basis of a predetermined condition such as returning of an accelerator grip, and when the continuation is unnecessary, normal map control is automatically restored.
29 Citations
28 Claims
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1. A controller of a continuously variable transmission (CVT) mounted on a vehicle, which includes an engine and an accelerator manipulating element manipulated by hand to control an accelerator, the controller including
an accelerator manipulated variable detector that detects a manipulated variable of the accelerator manipulating element, and a speed change ratio controller that sets a target speed change ratio of the CVT on the basis of the manipulated variable of the accelerator manipulating element and controls the CVT so that a current speed change ratio, that the CVT reaches, becomes the target speed change ratio, and wherein the speed change ratio controller comprises a standard speed change ratio setting unit that sets a standard speed change ratio, according to a normal map, as the target speed change ratio so that V-N (vehicle speed-engine rotational frequency) characteristics prescribed by a vehicle speed and an engine rotational frequency fall in a predetermined region of speed change that has a top limit defined by V-N characteristics determined when the accelerator is fully opened to accelerate under a condition of a normal load and a lower limit defined by V-N characteristics determined when the accelerator is fully closed to decelerate under the condition of the normal load, when the manipulated variable of the accelerator manipulating element is in a predetermined standard range, the normal map being set so that the V-N characteristics do not get out of the predetermined region of speed change, a specific speed change ratio setting unit that corrects the standard speed change ratio and sets a corrected speed change ratio, which is outside the normal map, as the target speed change ratio so that the V-N characteristics get out of the predetermined region of speed change and the current speed change ratio, that the CVT reaches, becomes the target speed change ratio that gets the V-N characteristics out of the predetermined region of speed change so that the target speed change ratio is set without being restricted by the predetermined region of speed change, when the manipulated variable of the accelerator manipulating element exceeds the standard range, and an automatic return unit that, when the V-N characteristics get out of the predetermined region of speed change, resets the target speed change ratio so that the V-N characteristics having gotten out of the predetermined region of speed change return to the predetermined region of speed change and the current speed change ratio, that the CVT reaches, becomes the target speed change ratio that returns the V-N characteristics to the predetermined region of speed change.
Specification