Apparatus for driving an elongated piece into and/or out of the ground

In a drilling apparatus wherein means are connectible with an elongated tubular piece to form a tubular anvil at one end thereof for the transmission of impact forces to the piece, a drill string is inserted through the anvil into the one end of the piece, and the piece is driven into the ground or the like by impacting the anvil while the drill string is operated in the piece, the improvement comprising a support, an anvil-impacting ram movably guided on the support to reciprocate along an axis parallel to the longitudinal axis of the piece, said ram having an axial bore therethrough to enable the drill string to be inserted therethrough and a plurality of hollow chambers operatively symmetrically enclosed therewithin about the bore, said support having means thereon defining elongated guides in the respective chambers and septa thereon which are relatively fixed in the chambers transverse the reciprocable axis of the ram to form pistons separating the relatively axially opposing end portions of the chambers, said axially opposing end portions of the chambers having a common cross-sectional area about the guides transverse the reciprocable axis of the ram, and means for driving the ram with equal force in the alternate reciprocable directions thereof, including a source of gaseous fluid under pressure, valve means interconnecting the gaseous fluid source with the respective end portions of the chambers through the opposing end portions of the guides to admit the pressurized fluid to corresponding portions of the chambers independently of one another and independently of the opposing portions thereof and vice versa, means defining an outlet for discharging the used fluid to atmosphere, control means on the ram and the suppport which are cooperatively engagable with one another adjacent the reciprocable path of the ram and responsive to reciprocation of the ram to cause the valve means to admit the fluid to corresponding portions of the chambers while the use fluid is exhausted to the outlet from the opposing portions of the chambers and vice versa, and means connected with the valve means to reverse the fluid flow to and from the respective corresponding and opposing portions of the chambers when the ram has undergone a predetermined length of travel in each reciprocable direction thereof, said valve means including a reciprocable valve member and means for applying a pair of mutually opposing fluid pressure signals to the valve member to balance the same against reciprocation, and said control means including a pair of spaced parallel grooves in one face of the ram which are mutually offset longitudinally the reciprocable axis of the ram to form collateral mutually longitudinally offset lands on the one face of the ram, and fluid connections between the respective fluid pressure signals on the valve member and points in the paths of the respective grooves in the one face of the ram and the lands corresponding thereto, whereby the respective fluid pressure signals are alternately discharged to a relatively low pressure zone in the respective grooves while the opposing signals are closed to the same by the lands, to generate a differential between the signals to unbalance the valve member in the sense of admitting the fluid to one portion of each chamber while the used fluid is exhausted to the outlet from the other portion thereof, and vice versa.

In a drilling apparatus wherein means are connectible with an elongated tubular piece to form a tubular anvil at one end thereof for the transmission of impact forces to the piece, a drill string is inserted through the anvil into the one end of the piece, and the piece is driven into the ground or the like by impacting the anvil while the drill string is operated in the piece, the improvement comprising a support, an anvil-impacting ram movably guided on the support to reciprocate along an axis parallel to the longitudinally axis of the piece, said ram having an axial bore therethrough to enable the drill string to be inserted therethrough and a plurality of hollow chambers operatively symmetrically enclosed therewithin about the bore, said support having means thereon defining elongated guides in the respective chambers and septa thereon which are relatively fixed in the chambers transverse the reciprocable axis of the ram to form pistons separating the relatively axially opposing end portions of the chambers, said axially opposing end portions of the chambers having a common cross-sectional area about the guides transverse the reciprocable axis of the ram, and means for driving the ram with equal force in the alternate reciprocable directions thereof, including a source of gaseous fluid under pressure, valve means interconnecting the gaseous fluid source with the respective end portions of the chambers through the opposing end portions of the guides to admit the pressurized fluid to corresponding portions of the chambers independently of one another and independently of the opposing portions thereof and vice versa, means defining an outlet for discharging the used fluid to atmosphere, control means on the ram and the support which are cooperatively engagable with one another adjacent the reciprocable path of the ram and responsive to reciprocation of the ram to cause the valve means to admit the fluid to corresponding portions of the chambers while the used fluid is exhausted to the outlet from the opposing portions of the chambers and vice versa, and means connected with the valve means to reverse the fluid flow to and from the respective corresponding and opposing portions of the chambers when the ram has undergone a predetermined length of travel in each reciprocable direction thereof, the control means including a pair of spaced parallel grooves in one face of the ram which are mutually offset longitudinally the reciprocable axis of the ram to form collateral mutually longitudinally offset lands on the one face of the ram, and sensory means operatively opposed to the grooves and lands to interface with points in the paths of the same on reciprocation of the ram to cause the valve means to admit the fluid to one portion of each chamber while the used fluid is exhausted to the outlet from the other portion thereof, and vice versa.

In apparatus wherein means connectible with an elongated piece to form an anvil on one end thereof for the transmission of impact forces to the piece, and the piece is driven into the ground or the like by impacting the anvil, the improvement comprising support means, an anvil impacting ram movably guided on the support means to reciprocate along an axis parallel to the longitudinal axis of the piece, said ram having a plurality of hollow chambers operatively symmetrically enclosed therewithin and said support means having means thereon defining elongated guides in the respective chambers and septa thereon which are relatively fixed in the chambers transverse the reciprocable axis of the ram to form pistons which separate the relatively axially opposing sets of end portions of the chambers from one another, and drive means for reciprocating the ram through the stroke thereof, including means defining a source of pressurized gas and an outlet for exhausting used gas to atmosphere, valve means operable to interconnect the pressurized gas source and the outlet with alternate but opposing sets of chamber portions, and means responsive to reciprocation of the ram to operate the valve means including means defining a pair of elongated control surfaces extending parallel to the reciprocable axis of the ram on one laterally oriented face of the ram, and having first portions thereof spaced apart from one another along lines extending parallel to the reciprocable axis of the ram, to correspond to the end portions of the stroke of the ram, said surfaces being mutually offset from one another longitudinally of the axis so that they have second portions thereof which overlap one another longitudinally of the axis from line to line, sensor means disposed adjacent the one face of the ram on the support means to register with the control surfaces during the stroke of the ram, and actuator means operable to cause the valve means to admit the pressurized gas to one set of chamber portions while discharging used gas to the outlet from the other set of chamber portions when the sensory means are in registry with the respective first portions of the control surfaces and the second portions thereof are moving relatively toward the sensory means, and to cause the valve means to reverse the gas flow to and from the respective sets of chamber portions when the sensory means are in registry with the respective first portions of the control surfaces and the second portions thereof are moving relatively away from the sensory means.

A ram for use in apparatus wherein means are connectible with an elongated piece to form an anvil on one end thereof and the piece is driven into the ground or the like by impacting the anvil with a reciprocable ram driven by a drive mechanism that is operated by a valve which is reciprocably mounted in a normally balanced two directional fluid pressure circuit to reciprocate in the alternate directions thereof when the circuit is unbalanced in the respective directions thereof, said circuit having a pair of fluid outlets therein which are connected with the opposing ends of the valve and disposed to slidably engage with the ram during the stroke thereof, comprising an anvil impacting body having a striking surface on one end thereof and a pair of grooves in one laterally oriented face thereof which are mutually offset longitudinally the reciprocable axis of the body on spaced parallel lines to form collateral mutually longitudinally offset lands on the lines, and which are adapted in axial extent, respectively, to discharge fluid from one of the outlets while the corresponding land covers the other outlet, and vice versa, to generate opposing fluid pressure differentials in the circuit across the valve and thereby unbalance the circuit in the respective directions thereof, when the body is reciprocably supported and guided in the apparatus and driven by the mechanism so that the lines of the grooves and lands intersect the outlets.