BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described further, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is, as earlier described, a schematic representation of the interior of a four position switch in which the individual positions of the switch can be set to latched or momentary.
FIG. 2 shows the cam plate of FIG. 1.
FIG. 3 is a view similar to that of FIG. 1 showing an embodiment of the invention.
FIG. 4 shows the second cam plate of the embodiment of the invention shown in FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The configurable switch of FIG. 3 includes all the components described previously and these have been allocated the same reference numerals to avoid the need to describe them a second time. The main difference resides in the addition of a second cam plate 122 with a cam track 123 which interacts in the same manner as described previously with a detent 124, a spring plate 126, a catch 128 and a solenoid 132. These components obscure from view the detent 24, spring plate 26, catch 28 and solenoid 32 that interact with the first cam plate 22 and are still present.
The cam track 123 in this case has a cam profile resembling ratchet teeth which define stops interacting with a detent 126 which acts as a pawl. Hence, in the position illustrated in FIG. 3, the control lever 10 while in the neutral position can be pivoted only towards the forward and extended forward positions and is prevented from movement towards the reverse position. If the detent 124 engages the other ratchet tooth defined by the cam track 123, the control lever will only be able to move between the forward and extended forward positions and will be inhibited from reaching the neutral and reverse positions.
Hence, the cam 122 and the selective energizing of the solenoid 132 will determine the number of switch positions while the cam 22 and the selective energizing of the solenoid 32 will determine whether each of the switch positions is a latched or a momentary position.
In this way, the invention allows the same configurable switch to control any of the functions of a tractor and after its function has been selected the switch will operate in exactly the same way as a switch dedicated to that function.
A useful feature of the switch shown in FIG. 3 is that it additionally includes a display panel 150 to allow the function controlled by the switch to be displayed to the operator by means of a text message or preferably an icon.
Though described by reference to an electrical switch, it will be clear to the person skilled in the art that the switch module 18 could be replaced by hydraulic or pneumatic valves and that applications of the invention are not limited to tractors and agricultural vehicles.
Patent Application
20070284237
