BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described, by way of example, with reference to the accompanying drawings in which:
FIG. 1 is an example of a design for determining an actuating pressure of an operating element from the deformation of a shifting fork;
FIG. 2 is an example of a design for determining an actuating pressure of an operating element from the deformation of spring elements in the operating element.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows one example of a design for determining a shifting pressure in an operating element 1, for example in an actuating cylinder. Pressurant lines 2, 3 are connected to pressure chambers 6, 7 of the actuating cylinder 1. The actuating cylinder 1 comprises a cylinder 5, a piston 4 and a piston rod 16. The piston rod 16 is connected to a shifting rod 8 on which a shifting fork 10 is located. The shifting fork 10 engages a sliding sleeve 11, which can move axially on a shaft 15, for example a gear shaft. By appropriately activating a pressure regulating device (not shown here), an appropriate control pressure is applied on the pressurant line 2, thus creating the appropriate shifting force in the pressure chamber 6 of the actuating cylinder 1. As a result of this control pressure and/or the shifting force in the pressure chamber 6 of the actuating cylinder 1, the piston 4 in the cylinder 5 and the piston rod 16 attached to the piston 4 are moved, to the right in the plane of FIG. 1. The piston 4 and the piston rod 16 can also be produced from one piece. As a result of the displacement of the piston 4 and thus of the piston rod 16, to the right in the plane of FIG. 1, the shifting rod 8, the shifting fork 10 and the sliding sleeve 11 are also displaced to the right. The piston 4 is thus displaced until the sliding sleeve 11 hits against a stop 12a, for example the teeth on a shifting gear. This displacement corresponds to the nominal displacement of the actuating cylinder 1. When the actuating pressure in the pressure chamber 6 of the actuating cylinder 1 is greater than is required for the nominal displacement, the shifting rod 8 is displaced further to the right, resulting in a deformation of the shifting fork 10. By subtracting the nominal displacement from the total displacement of the piston 4, a difference in displacement 9 is obtained, which results from the deformation of the shifting fork 10. This difference 9 can be used in a device, such as a regulating and control unit, to compute the actuating pressure in the pressure chamber 6 of the actuating cylinder 1 with the pressure influenced by corresponding control and regulating functions.
The sliding sleeve 11 is actuated toward the left in the plane of FIG. 1 in a mirror process. The pressure chamber 7 in this case is supplied with an actuating pressure, via the pressurant line 3, to displace the piston 4 in the cylinder 5 to the left. The piston 4 is displaced until the sliding sleeve 11 hits against a stop 12b, for example, the teeth of a shifting gear.
FIG. 2 shows another example of a design for determining a shifting pressure in the operating element 1, for example in an actuating cylinder. Unlike in FIG. 1, the actuating pressure of the actuating cylinder 1 is not determined from a deformation of the shifting fork 10, but rather from a deformation of a spring element 13, 14. For this purpose, spring elements 13, 14 are positioned between the piston 4 and the limit stops of the actuating cylinder 1. By appropriately activating a pressure regulating device (not shown here), an appropriate control pressure is applied on the pressurant line 2 and thus in the pressure chamber 6 of the actuating cylinder 1. As a result of this control pressure and/or the shifting force in the pressure chamber 6 of the actuating cylinder 1, a piston 4 in the cylinder 5 and a piston rod 16 on the piston 4 are displaced to the right in the plane of FIG. 2. The piston rod 16 is connected to the shifting rod 8. As a result of the displacement of the piston 4 and thus of the piston rod 16 to the right in the plane of FIG. 2, the shifting rod 8, the shifting fork 10 and the sliding sleeve 11, which can move axially on the shaft 15, are likewise displaced to the right. The piston 4 is displaced until it hits the spring element 13. This displacement corresponds to the nominal displacement of the actuating cylinder 1. When the actuating pressure in the pressure chamber 6 of the actuating cylinder 1 is greater than is required for the nominal displacement, the shifting rod 8 is displaced further to the right, resulting in a deformation of the spring element 13. By subtracting the nominal displacement from the total displacement of the piston 4, a difference in displacement 9 is obtained, which results from the deformation of the spring element 13. This difference 9 can be used in a device such as a regulating and control unit, to determine the actuating pressure in the pressure chamber 6 of the actuating cylinder 1 such that the pressure can be influenced by corresponding control and regulating functions.
The sliding sleeve 11 is actuated to the left in the plane of FIG. 2 in a mirror process. The pressure chamber 7 in this case is supplied with an actuating pressure, via the pressurant line 3, to displace the piston 4 in the cylinder 5 to the left. When the actuating pressure in the pressure chamber 7 of the actuating cylinder 1 is greater than required for the nominal displacement, the shifting rod 8 is displaced further to the left, resulting in a deformation of the spring element 14.
REFERENCE NUMERALS
1 operating element, actuating cylinder
2 pressurant line for the operating element
3 pressurant line for the operating element
4 piston
5 cylinder
6 pressure chamber
7 pressure chamber
8 shifting rod
9 difference in displacement due to deformation
10 shifting fork
11 sliding sleeve
12
a stop
12
b stop
13 spring element
14 spring element
15 shaft
16 piston rod
Patent Application
20070256483
