A drill comprising a drill bit comprising a first drill part and a second drill part configured to slide relative to each other, wherein the first and second drill parts are pivotally coupled at one end to a first member and a second member respectively; a cam engaged with the first member and the second member, wherein the first and second members act as followers to slide the parts of the drill bit in a reciprocating motion with respect to each other, between a retracted and an extended position; and a wedge comprising a first angled surface engaged with the first member and a second angled surface engaged with the second member, the wedge configured to urge the drill bit to pivot in a first direction when the first member is moved towards the retracted position and to pivot in a second direction when the second member is moved towards the retracted position.

A drill comprising a drill bit comprising a first drill part and a second drill part configured to slide relative to each other, wherein the first and second drill parts are pivotally coupled at one end to a first member and a second member respectively; a cam engaged with the first member and the second member, wherein the first and second members act as followers to slide the parts of the drill bit in a reciprocating motion with respect to each other, between a retracted and an extended position; and a wedge comprising a first angled surface engaged with the first member and a second angled surface engaged with the second member, the wedge configured to urge the drill bit to pivot in a first direction when the first member is moved towards the retracted position and to pivot in a second direction when the second member is moved towards the retracted position.

An experimental apparatus for rock-breaking through vibration impact, including a confining pressure loading assembly, a drill bit, a drill rod, a drilling fluid circulation assembly, a rotary impact assembly and an axial impact assembly. The confining pressure loading assembly is configured to apply pressures to a core sample located in a core cavity in three directions perpendicular to each other. The drill bit is capable of inserting into the core cavity to drill the core sample. The drilling fluid circulation assembly includes a drilling fluid inlet, a drilling fluid outlet and a mud pump connected therebetween. The rotary impact assembly includes a hydraulic rotary motor and a hydraulic swing motor connected to the drill rod, respectively. The axial impact assembly includes a first hydraulic cylinder, and a servo linear actuator connected to the first hydraulic cylinder and the drill rod.

An experimental apparatus for rock-breaking through vibration impact, including a confining pressure loading assembly, a drill bit, a drill rod, a drilling fluid circulation assembly, a rotary impact assembly and an axial impact assembly. The confining pressure loading assembly is configured to apply pressures to a core sample located in a core cavity in three directions perpendicular to each other. The drill bit is capable of inserting into the core cavity to drill the core sample. The drilling fluid circulation assembly includes a drilling fluid inlet, a drilling fluid outlet and a mud pump connected therebetween. The rotary impact assembly includes a hydraulic rotary motor and a hydraulic swing motor connected to the drill rod, respectively. The axial impact assembly includes a first hydraulic cylinder, and a servo linear actuator connected to the first hydraulic cylinder and the drill rod.

An experimental apparatus for rock-breaking through vibration impact, including a confining pressure loading assembly, a drill bit, a drill rod, a drilling fluid circulation assembly, a rotary impact assembly and an axial impact assembly. The confining pressure loading assembly is configured to apply pressures to a core sample located in a core cavity in three directions perpendicular to each other. The drill bit is capable of inserting into the core cavity to drill the core sample. The drilling fluid circulation assembly includes a drilling fluid inlet, a drilling fluid outlet and a mud pump connected therebetween. The rotary impact assembly includes a hydraulic rotary motor and a hydraulic swing motor connected to the drill rod, respectively. The axial impact assembly includes a first hydraulic cylinder, and a servo linear actuator connected to the first hydraulic cylinder and the drill rod.

An experimental apparatus for rock-breaking through vibration impact, including a confining pressure loading assembly, a drill bit, a drill rod, a drilling fluid circulation assembly, a rotary impact assembly and an axial impact assembly. The confining pressure loading assembly is configured to apply pressures to a core sample located in a core cavity in three directions perpendicular to each other. The drill bit is capable of inserting into the core cavity to drill the core sample. The drilling fluid circulation assembly includes a drilling fluid inlet, a drilling fluid outlet and a mud pump connected therebetween. The rotary impact assembly includes a hydraulic rotary motor and a hydraulic swing motor connected to the drill rod, respectively. The axial impact assembly includes a first hydraulic cylinder, and a servo linear actuator connected to the first hydraulic cylinder and the drill rod.

The present invention relates to a drilling device. The device comprises at least one drill rod, the or each drill rod having a first cylindrical wall defining an elongate chamber for receiving a working fluid to form a fluid column, the length of the fluid column being equal to a total length of the elongate chambers of the or each drill rod. The device also comprises a displacement excitation device arranged at a proximal end of the fluid column and configured to excite the fluid column to cause the working fluid in the fluid column to oscillate, wherein the excitation device is configured to excite the fluid column at an excitation frequency at or within 10% of a natural frequency of the fluid column determined based on the fluid column having a fixed boundary condition at a proximal end thereof. The device further comprises a tool piston moveably mounted at a distal end of the fluid column and a drilling tool connected to the tool piston such that the oscillation of the working fluid in the fluid column imparts an oscillating force to the drilling tool.

The device is operated with a conventional rotary drive with pile hammer. The torque and the ramming impacts of the drill head are transmitted to a drilling initial tube with drill bit. A sleeve without rotation stands inside the rotating initial tube. It rests at the bottom on the inside of the drill bit rotating below it. As a special feature, the sleeve is connected to the rotating drill head by means of a sleeve adapter with axially consecutive parts that can be rotated against each other and a PFR pressure, flushing and recovery tube connected to it. The PFR rotates with the drill head and the drill pipe, and the sleeve adapter communicates with the non-rotating sleeve. The PFR is used firstly to apply compressive force to the sleeve from above, secondly to flush it by guiding the flushing water for drilling in the PFR and forcing it out of the sleeve, and thirdly to allow the sleeve to be recovered for an almost undisturbed drilling test.

The device is operated with a conventional rotary drive with pile hammer. The torque and the ramming impacts of the drill head are transmitted to a drilling initial tube with drill bit. A sleeve without rotation stands inside the rotating initial tube. It rests at the bottom on the inside of the drill bit rotating below it. As a special feature, the sleeve is connected to the rotating drill head by means of a sleeve adapter with axially consecutive parts that can be rotated against each other and a PFR pressure, flushing and recovery tube connected to it. The PFR rotates with the drill head and the drill pipe, and the sleeve adapter communicates with the non-rotating sleeve. The PFR is used firstly to apply compressive force to the sleeve from above, secondly to flush it by guiding the flushing water for drilling in the PFR and forcing it out of the sleeve, and thirdly to allow the sleeve to be recovered for an almost undisturbed drilling test.