초록 ▼

A device for controlling a hydraulically operable switching element (2) of an automatic transmission of a vehicle with a position valve mechanism (3) having a main switch piston (6) which is spring biased into a first switch position and a second switch position with a pilot pressure (P_MV) which is

A device for controlling a hydraulically operable switching element (2) of an automatic transmission of a vehicle with a position valve mechanism (3) having a main switch piston (6) which is spring biased into a first switch position and a second switch position with a pilot pressure (P_MV) which is adjustable through an electrically operated actuator (5). An additional switch piston (7) and the main switch piston (6) are axially actuated in a valve housing (8). Depending on the position of the pistons (6, 7), faces (6A, 7A) of the respective pistons are either spaced apart or adjacent. The additional switch piston (7) is adjustable depending on a pilot pressure (p_K) of a switching element which engages a gear for forward drive.

대표청구항 ▼

The invention claimed is: 1. A device (1) for controlling a single hydraulic switching element (2) of an automatic transmission of a vehicle, the device (1) comprising: a position valve mechanism (3) including a system pressure input port (32), a system pressure output port (33), at least two contr

The invention claimed is: 1. A device (1) for controlling a single hydraulic switching element (2) of an automatic transmission of a vehicle, the device (1) comprising: a position valve mechanism (3) including a system pressure input port (32), a system pressure output port (33), at least two control ports (36, 37, 38), a main switch piston (6), and an additional switch piston (7); and the additional switch piston (7) and the main switch piston (6) each being coaxially slidable within a valve housing (8) between respective first and second positions; and a pressure regulation valve (10) including an input port (101), an output port (102), a first control port (105) and a valve gate piston (12) coaxially slidable in a valve housing (11) between a first position and second position; wherein the main switch piston (6) is resiliently biased into its first switch position and hydraulically biased into its second switch position by an adjustable actuator pilot pressure (p_MV); the additional switch piston (7) is hydraulically biased, via a working chamber (9), to its second switch position with a switching element pilot pressure (p_K); the main switch piston (6) has a control area located between two lands of the main switch piston (6), the main switch piston (6) control area having a reduced diameter compared to the two lands, the system pressure input port (32) is connected to a system pressure (p_sys), and the system pressure output port (33) is connectable with the system pressure input port (32), depending on an axial position of the main switch piston (6), for controllably providing the system pressure (p_sys) at the system pressure output port (33); the additional switch piston (7) has a control area located between two lands (18, 19) of additional switch piston (7), the control area having a reduced diameter compared to the two lands (18, 19), a first of the at least two control ports (36) is connected to a valve mechanism pilot pressure (p_EDS) and is connectable with a second of the at least two control ports (37, 38), depending on an axial position of the additional switch piston (7), for controllably providing the valve mechanism pilot pressure (p_EDS) at the second of the at least two control ports (37, 38); the valve gate piston (12) being resiliently biased toward its first position and hydraulically biased toward its second position by the valve mechanism pilot pressure (p_EDS) provided to the first control input port (105) of the pressure regulation valve (10) from the second of the at least two control ports (37, 38) of the position valve mechanism (3); the valve gate piston (12) having a regulation control area located between two lands of the valve gate piston (12), and the regulation control area having a reduced diameter compared to the two lands, the input port (101) of the pressure regulation valve (10) is connected to the system pressure (p_sys) output port (33) of the position valve mechanism, and the output port (102) of the pressure regulation valve (10) controllably providing a switching element control pressure (p--2) to the switching element (2) of the clutch, depending on the position of the valve gate piston (12), and the switching element control pressure (p--2) is controlled by the adjustable actuator pilot pressure (p_MV), the valve mechanism pilot pressure (p_EDS) and the switching element pilot pressure (p_K). 2. The device according to claim 1, wherein the first of the at least two control ports (36) is combinable with the second of the at least two control ports (37) in the second position of the additional switch piston (7), and is supplied with the valve mechanism pilot pressure (p_EDS) for setting the switching element control pressure (p--2) of the switching element (2); and the second of the at least two control ports (37) is combinable with a further of the at least two control ports in the first position of the additional switch piston (7), and the second of the at least two control ports is connected to a control port (105) of the pressure regulation valve (10). 3. The device according to claim 1, wherein, in the first switch position of the main switch piston (6), the working chamber (9) of the position valve mechanism (3) communicates with a release space (16).