Patent ID: 6050346
Filing Date: 2000-04-18
Classification: E21B

Abstract:
A fluid operated drill motor that operates with gaseous or liquid well drilling fluid or drilling mud, comprising:a) an elongated tool body having a flow bore, an upper end portion with a connector that enables the tool body to be attached to work string, and a lower connector that enables a drill bit to be connected to the lower end of the tool body;b) a reciprocating valving member that travels between a first upper and a second lower position within the tool body bore;c) a piston carried in the tool body bore below the valving member, the piston having an upper end portion with a valve seat, and the valving member having a lower end portion that can form a seal with the seat;d) the piston being powered to move downwardly within the flow bore with the valving member from differential fluid pressure applied to the combination of valving member and piston when the valving member lower end portion forms said seal at said seat;e) compressible valving member spring positioned in the tool body to engage the valving member, the springs gradually compressing as the valving member moves downwardly within the flow bore;f) a full compression of the valving member springs enabling the springs to override the fluid pressure acting on the combination of piston and valving member so that the valving member can separate from the piston and its seat;g) a drill bit attached to the lower connector; andh) a transmission that rotates the drill bit without transmitting impact thereto from the reciprocating piston and valving member.