초록 ▼

A hydraulic circuit for borehole telemetry apparatus is presented wherein a mud pulse valve is operated by hydraulic pressure applied to differential areas of an actuating piston. The system includes a hydraulic pump, a filter in the line between the pump and the piston to be actuated, an accumulato

A hydraulic circuit for borehole telemetry apparatus is presented wherein a mud pulse valve is operated by hydraulic pressure applied to differential areas of an actuating piston. The system includes a hydraulic pump, a filter in the line between the pump and the piston to be actuated, an accumulator upstream of the filter, a regulating and relief valve downstream of the filter, and solenoid actuated valves to control delivery of hydraulic fluid to the piston. The system also includes a pressure compensating bellows to compensate for changes in pressure in the drilling mud.

대표청구항 ▼

A hydraulic circuit for borehole telemetry apparatus, including: pump means for delivering pressurized hydraulic fluid to a first conduit; filter means positioned in said first conduit from said pump means to receive hydraulic fluid from said pump means; return conduit means for returning hydraulic

A hydraulic circuit for borehole telemetry apparatus, including: pump means for delivering pressurized hydraulic fluid to a first conduit; filter means positioned in said first conduit from said pump means to receive hydraulic fluid from said pump means; return conduit means for returning hydraulic fluid to the inlet to said pump means; second conduit means for delivering hydraulic fluid from said filter means to valve actuator means to actuate said valve actuator means in a first direction; regulating and relief valve means connected to said second conduit means downstream of said filter means and between said second conduit means and said return conduit means; third conduit means connected to said second conduit means downstream of the connection to said regulating and relief valve means; solenoid valve means connected to said third conduit means and to said return conduit means; fourth conduit means between said solenoid valve means and said valve actuator means; said solenoid valve means in a first position thereof delivering pressurized hydraulic fluid to said valve actuator via said third and fourth conduit means to actuate said valve actuator means in a second direction, and said solenoid valve means in a second position thereof connecting said fourth conduit means to said return conduit means to return hydraulic fluid to the inlet of said pump; and pressure compensation means connected to said return conduit means to vary the pressure of hydraulic fluid in said return conduit means as a function of changes in pressure of an environment to which said pressure compensating means is exposed.