Patent Application
20070246015
The present invention relates generally to solenoid-operated valves, and more particularly to sensing the position of the plunger of a vehicle valve.
Modern vehicles have many control systems in which a controller, in response to sensor signals, actuates vehicle components to control the vehicle. As one illustration, an engine control module (ECM) might receive input from various sensors and in response turn “on” and “off” actuation coils of various hydraulic valves to cause an automatic transmission to shift. Some applications where actuators are utilized require armature position sensing to help protect the system against severe failure modes. Such is the case for valves that are used to direct fluid to the engine cylinders to help cool and lubricate them. Closed-loop feedback is used to detect whether the actuator function has degraded or been lost. As understood herein, a need for simply, inexpensively, and elegantly indicating valve position is required.
A valve has a valve body and a plunger disposed in the valve body and reciprocally movable therein. An actuating solenoid is disposed in a surrounding relationship with the plunger and is energizable to cause the plunger to move, while a position sensing coil is also disposed in a surrounding relationship with the plunger and outputs a signal representative of the position of the plunger.
In some embodiments the plunger may be formed with a first segment and a second segment having a diameter smaller than the diameter of the first segment, with the actuating solenoid surrounding the first segment and the position sensing coil surrounding the second segment. The actuating solenoid and position sensing coil can be coaxial with each other, and if desired the position sensing coil can have a smaller diameter than the actuating solenoid.
In non-limiting implementations a rod may be centrally disposed in the plunger and staked thereto. In the non-limiting implementation the rod extends through a stop that is press-fit into the valve body, and the rod terminates in a poppet.
In another aspect, a valve has an actuating solenoid, a position sensing coil axially spaced from the actuating solenoid, and a plunger axially movable centrally in the actuating solenoid and the position sensing coil.
In yet another aspect, a valve has a plunger, electrically energizable actuating means for moving the plunger, and coil means for sensing a position of the plunger.
The details of the present invention, both as to its structure and operation, can best be understood in reference to the accompanying drawings, in which like reference numerals refer to like parts, and in which:
The present invention is intended for application in automotive vehicle suspension systems and will be described in that context. It is to be understood, however, that the present invention could also be successfully applied in many other applications.
Referring initially to
A rod 30 is centrally affixed to the poppet 28 and has a smaller diameter than the poppet 28. The rod 30 extends down the center of the valve 10 through an immovable stop 32 that is affixed with the valve body 12 by, e.g., press-fitting and that radially bears the rod 30. The rod 30 is bound to a movable plunger 34 by a bond structure 36, which can be, in one non-limiting implementation, staking.
The plunger 34 can be moved by the energizable actuator solenoid 14. Surrounding the actuator solenoid 14 and disposed within or otherwise coupled to the valve body 12 is a frame 39. Coaxially aligned with the frame 39 is a secondary plate 41 with a diameter as large as that of the actuator solenoid 14.
In accordance with the present invention, the actuator solenoid 14 is disposed in a surrounding relationship with a first, relatively (radially) large segment 34a of the plunger 34. The plunger 34 is also formed with a second segment 34b that has a smaller diameter than the first segment 34a and that is surrounded by the position sensing coil 16. Accordingly, the position sensing coil 16 is coaxially aligned with the actuator solenoid 14 so that it outputs a signal that varies linearly with the position of the plunger 34 as shown in
In the non-limiting embodiment shown, a spring 42 may be coaxially aligned with the actuator solenoid 14 and disposed around the rod 30 to urge the plunger to the right looking down in
Once the actuator solenoid 14 is energized, the plunger 34 moves left looking down on
As mentioned above, the inductive sensing relationship to distance in one non-limiting implementation is shown in
While the particular SOLENOID-OPERATED VALVE WITH COIL FOR SENSING PLUNGER POSITION as herein shown and described in detail is fully capable of attaining the above-described objects of the invention, it is to be understood that it is the presently preferred embodiment of the present invention and is thus representative of the subject matter which is broadly contemplated by the present invention, and that the scope of the present invention is accordingly to be limited by nothing other than the appended claims, in which reference to an element in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more”. It is not necessary for a device or method to address each and every problem sought to be solved by the present invention, for it to be encompassed by the present claims. Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims.
