1. Related Applications
This application claims priority from British application No. 9003394.5 filed Feb. 14, 1990 and British application No. 9100926.6 filed Jan. 16, 1991.
2. Field of the Invention
The present invention relates to a rotational speed sensor assembly of the type comprising a rotating exciter fixed for rotation with the monitored device and a fixed probe transducer mounted to and extending through a housing for sensing relative rotation of the exciter.
In particular, the present invention relates to the structure of a speed sensor assembly probe transducer subassembly for mounting said probe in a fixed position extending through an aperture in a housing.
The probe transducer subassembly has a sensing probe end, an electrical termination/connection end and intermediate clamping and/or sealing means. The intermediate clamping/sealing means cooperate with a shroud allowing the probe end to be secured in a hostile environment subject to vibration, shock loading, lubricants and/or condensation.
3. Description of the Prior Art
Rotational speed sensor assemblies, especially for vehicular drive components, are well known in the prior art. Typically, such rotational speed sensor assemblies are utilized to sense the rotational velocity of a monitored object, such as a gear, shaft and/or wheel, relative to a fixed housing, or similar support. Examples of vehicular applications for rotational speed sensor assemblies include fully or partially automated transmission systems, anti-lock brake systems, differential lock-up systems and traction control systems. Examples of such systems may be seen by reference to U.S. Pat. Nos. 4,949,806; 4,947,331; 4,930,081; 4,849,899; 4,361,060; 4,263,824; 4,097,756; 4,724,935; 4,029,180; 4,804,237 and 3,966,267, the disclosures of which are incorporated herein by reference.
The rotational speed sensor assemblies typically comprise an exciter rotor subassembly rotationally fixed to the relatively rotatable monitored gear, shaft and/or wheel and a probe transducer subassembly fixed to a support housing and positioned in a predetermined manner relative to the exciter rotor.
Such rotational speed sensor assemblies are typically electromagnetic in nature and utilize the making and breaking of flux paths resulting from rotation of the exciter rotor relative to the probe to generate an induced current in the probe output, the magnitude, amplitude, and/or frequency of which is indicative of the relative rotational velocity of the exciter. In certain situations, the function of the exciter rotor may be provided by gear teeth, splines, or the like.
Examples of prior art vehicular rotational speed sensor assemblies may be seen by reference to U.S. Pat. Nos. 4,029,180; 4,862,025; 4,937,522; 4,893,075; 3,769,533; 4,854,556, 4,090,592 and 4,097,756, the disclosures of which are incorporated herein by reference.
A problem with prior art vehicular rotational speed sensor assemblies of the type having a probe transducer subassembly mounted to a housing and extending through an opening therein has been protecting the probe from damage due to vibrations, shock loadings, lubricants and/or water of condensation.
USPTO Backgrounds
USPTO Backgrounds