# Synthesis of the Energy-Saving Dry Dual Clutch Control Mechanism
## 3 Results  
Figure 6 shows the effect of carriage displacement \(\Delta_{K}\) on the force \(F_{npk}\) in the pressure spring and the force \(Q_{k}\) on the pressure disc when switching on the \(k\)-th clutch. A dry clutch is considered a test case for simulating the DCT workflow. This clutch is widely used in the automotive and agricultural industries. It also has the following parameters: \(L=0.053\) m, \(z_{1}=z_{2}=z=z_{c}+z_{y}\), \(z_{c}=2.0\) mm, \(z_{y}=0.8\) mm, \(c=950\) kN/m, \(\Delta_{0}=30\) mm. The analysis results presented in Figure 6 shows that the force on the pressure plate will be different for a uniform vertical movement of the carriage \(\Delta_{K}\) (when switching on the 1 st and the 2 nd clutches). Moreover, \(Q_{2}>Q_{1}\) and \(F_{np2}>F_{np1}\). In this case, \(F_{np1}\) changes insufficiently. An increase in \(\Delta_{K}\) increases the difference \(Q_{21}=Q_{2}\)--\(Q_{1}\) between forces on the pressure disc and decreases the clutch margin. Notably, such a difference in the pressure disc also increases but is lower. Hence, it is not possible to provide the same clutch margin. Moreover, equality \(Q_{1}=Q_{2}\) cannot be provided by choosing different carriage displacements (\(\Delta_{K1}\
eq\Delta_{K2}\)). Therefore, to equalize the clutch margin, it is proposed to abandon the strictly vertical movement of the carriage. It is also suggested to constructively realize an additional horizontal movement of the carriage. In this case, to equalize forces \(Q_{K1}\) and \(Q_{K2}\), the force \(Q_{K1}\) should increase, and the force \(Q_{K2}\) should be decreased. The corresponding change in the position of points \(P_{1}\) and \(P_{2}\) of the carriage contact with the pressure spring can achieve the last condition. In other words, the platter profile along which the carriage moves under switching on/off the DCT should be changed. In the proposed improved DCT design [32], rollers 21 and 22 move on the inclined conical surfaces 26 and 27 of the support disc. The corresponding design schemes are presented in Figure 7.  
It is convenient to characterize the clutch operation when the \(k\)-th clutch is switched on by changing the position of the rotary lever \(N_{k}P_{k}\) with the inclination angle \(\alpha_{k}\). The extreme positions of the friction pressure plates are conditionally marked by vertical lines \(M_{k}\). Point \(N_{k}\) of the rotary lever has the coordinate \(x_{Mk}=\text{const}\). The following dependencies determine the coordinates of characteristic points \(N_{k}\) and \(P_{k}\) for the swivel disc:  
\[ \begin{array}{ll}N_{k}:&x_{N_{k}}=(-1)^{k}z;&y_{N_{k}}=Lcos\alpha_{k};\\ P_{k}:&x_{P_{k}}=-(-1)^{j}(Lsin\alpha_{k}-z_{k});&y_{P_{k}}=0,\end{array}  \tag{9}\]  
where \(z_{k}=\left\lvert\,x_{Mk}\,\right\rvert.\)  
When the clutch is entirely switched on, gap neglect occurs, and the friction linings are elastically deformed. Therefore, the initial position of the rotary lever (at the initial position of the carriage \(G_{0}\)) can be represented by levers \(ON_{10}\) and \(ON_{20}\). In this case, \(x_{N10}=x_{M1}\), \(x_{N20}=x_{M2}\), and the initial inclination of the rotary disc is characterized by angles \(\alpha_{10}\), \(\alpha_{20}\). At a specific position of the rotary lever, the carriage position is determined from the following expressions:  
\[ \begin{array}{ll}G_{1}:&x_{G_{1}}=x_{P_{1}}+\Delta_{K1}tg\alpha_{1};&y_{G_{ 1}}=-\Delta_{K1};\\ G_{2}:&y_{G_{2}}=-\Delta_{K2};&x_{G_{2}}=x_{P_{2}}-\Delta_{K2}tg\alpha_{2}, \end{array}  \tag{10}\]  
where \(\Delta_{Kk}\)--vertical movement of the carriage [mm]. The pressing force \(Q_{k}\) of the friction pairs and the force \(F_{np1}\) from the pressure spring (when the \(j\)-th clutch is switched on) are determined by Formulas (5)-(8). The current deformation \(\Delta_{k}\) of the pressure spring (the value of \(OP_{k}\)) is determined by the coordinate \(x_{pk}\). For the investigated clutch design (Figure 1b), under the switching-off of the 1 st clutch, the pressure spring is additionally compressed (\(\Delta_{1}>0\)).