Topic
Variator
About: Variator is a research topic. Over the lifetime, 2537 publications have been published within this topic receiving 12558 citations.
Papers published on a yearly basis
1 / 2
Papers
Patent•
12 Jan 1994
TL;DR: In this article, the authors considered a continuously variable-ratio transmission (CVT) with a variator and a power-recirculating epicyclic (E) for toroidal-race rolling-traction.
Abstract: A continuously-variable-ratio transmission ('CVT'), for instance of the toroidal-race rolling-traction type, capable of geared neutral and of operating in at least two regimes and including a ratio-varying component ('variator') (4), a power-recirculating epicyclic (E), a final drive shaft (1) connectable with the variator (4) by way of one of two alternative driven shafts (A, B) and an input epicyclic (e) the input (35) of which is connectable to a prime mover (3) and the two outputs (36, 40) of which are connected to the two alternative driven shafts (A, B) respectively. One of the regimes includes a 'geared neutral' condition, and the power-recirculating epicyclic (E) is associated with clutches (44, 46) whereby power is recirculated through it in that regime. In the remaining one or more regimes no power is recirculated within that epicyclic (E), but drive reaches the CVT output (1) by way of appropriate clutches (44, 46; 48, 47; 49; 45) and whichever of the two driven shafts (A, B) will rise in speed as that regime proceeds.
120 citations
TL;DR: In this paper, a detailed experimental study of the pushing V-belt CVT dynamics and compare the experimental data with the theoretical predictions of the Carbone, Mangialardi, Mantriota (CMM) model is presented.
115 citations
Patent•
31 May 1989TL;DR: In this paper, a lens position control device for an optical instrument, the instrument including a variator and a compensator, the latter of which also serves as a focusing lens, comprises a detecting circuit for detecting the positions of the variators and the focusing lenses, a memory for storing information representing the location and size of an impossible-to-focus zone for the focusing lens as the function of the zooming position of the variable, and a control circuit responsive to detection of the fact that the focus lens falls in the impossible to focus zone on the basis of the information stored
Abstract: A lens position control device for an optical instrument, the instrument including a variator and a compensator, the latter of which also serves as a focusing lens, comprises a detecting circuit for detecting the positions of the variator and the focusing lens, a memory for storing information representing the location and size of an impossible-to-focus zone for the focusing lens as the function of the zooming position of the variator, and a control circuit responsive to detection of the fact that the focusing lens falls in the impossible-to-focus zone on the basis of the information stored in the memory for causing the focusing lens to retire from the impossible-to-focus zone or for prohibiting the focusing lens from further moving in a direction toward the impossible-to-focus zone.
97 citations
Patent•
5 Mar 2010
TL;DR: In this paper, the transmission controller changes the gear position of the subtransmission mechanism and varies the speed ratio of the variator in an opposite direction to a speed ratio variation direction when the actual through speed ratio passes a predetermined mode switch line.
Abstract: The transmission controller changes the gear position of the subtransmission mechanism and varies the speed ratio of the variator in an opposite direction to a speed ratio variation direction of the subtransmission mechanism when the actual through speed ratio passes a predetermined mode switch line. When the improvement in the shift response of the continuously variable transmission is determined to be required and the actual through speed ratio passes the mode switch line from a Low side to the High side, the transmission controller increases a shift speed of the subtransmission mechanism compared with a normal coordinated shift.
89 citations
TL;DR: In this paper, a one-dimensional model of a metal belt CVT was used to analyze the shifting behavior of a CVT with respect to the variation of the local groove width caused by the elastic deformation of the pulleys and by the clearance in the bearings.
Abstract: This paper is concerned with the shifting behavior of a metal belt CVT. The calculations are performed for the chain belt case by using a one-dimensional model of the belt: the radial thickness of the belt is neglected. The friction forces are modeled on the basis of the Coulomb friction hypothesis. The deformation of the belt, i.e., the variation of its transversal width, is shown to be negligible with respect to the variation of the local groove width caused by the elastic deformation of the pulleys and by the clearance in the bearings. The particular shape of the deformed pulley is described on the basis of Sattler model (1999) who showed that the variation of the groove angle and that one of the local groove width of the pulley can be easily described by simple trigonometric formulas. The paper shows that the characteristic behavior of the transmission during slow shifting maneuvers, referred to as "creep mode, " is caused by the bending of the pulleys, that is to say for rigid pulleys no "creep mode" can be observed. Moreover, the model shows that increasing the rate of change of speed ratio a transition from the "creep-mode" to the so called "slip-mode" behavior of the variator takes place, as experimentally observed.
81 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 10 |
| 2020 | 31 |
| 2019 | 39 |
| 2018 | 74 |
| 2017 | 83 |
| 2016 | 75 |