Abstract: A compound of formula (I): wherein all symbols have the same meanings as defined in the specification; a salt thereof, a solvate thereof, an N-oxide thereof, or a prodrug thereof, has a Btk inhibitory activity, and is useful as a method for preventing and/or treating a rheumatoid arthritis, an autoimmune disease, a B cell lymphoma of cancer, and the like.

Abstract: Disclosed are substituted benzimidazole compounds of formula (I): wherein R1, R2, R3, R4 and Xa are defined herein. The compounds of the invention inhibit Itk kinase and are therefore useful for treating diseases and pathological conditions involving inflammation, immunological disorders and allergic disorders. Also disclosed are processes for preparing these compounds and to pharmaceutical compositions comprising these compounds.

Abstract: The invention is directed to an auxiliary drive system for the front wheels of a belted track crawler. The auxiliary drive wheels and the main drive wheels are provided with overrunning clutches. In the first two embodiments a mechanical system is used to drive the auxiliary wheels. In the third embodiment electric motors are used to drive the auxiliary wheels. With all the systems when the crawler is being driven forward the auxiliary drive wheel is driven slower than the main drive wheel. In a no slip situation the auxiliary drive wheel freely rotates at the speed of the main drive wheel. When sufficient slippage occurs between the main drive wheel and the track, the auxiliary drive wheel is driven at the slower speed driving the track. In reverse, the auxiliary drive wheel is driven faster than the main drive wheel. In a no slip condition, the auxiliary drive wheel drives the crawler in reverse.

Abstract: A crawler having a friction driven elastomeric belted track which is driven by rear mounted main drive wheels and front mounted auxiliary drive wheels. The auxiliary drive wheels are operatively coupled through hydraulic clutches to hydraulic motors that are fluidically coupled to a reversible variable displacement pump. An electronic controller controls the output of the pump so that the auxiliary drive wheels are driven at a speed less than the main drive wheels in the forward direction at a speed equal to or greater than the speed of the main drive wheels in the reverse direction. A valve assembly selectively couples and decouples the hydraulic clutches for engaging and disengaging the motor when turning the vehicle.