Abstract: The optimized soil penetrating machine is characterized by parameters that are optimized with respect to maximum kinetic energy that the machine cyclically obtains for soil deformation during the forward mode of operation. The optimization of the parameters is based on the author's analytical investigation that revealed the existence of the optimal values of the lengths of the striker and its forward stroke at which the machine's kinetic energy reaches its maximum value, resulting in the maximum performance efficiency. The investigation shows that the optimal value of the length of the striker is shorter than the length of its forward stroke. In the existing machines the striker is longer than its forward stroke. This investigation also shows that the efficiency of the existing machines is about 2.5 times less than for their optimized hypothetical counterparts. Since the existing machines cannot be optimized it is required to implement new design concepts.

Abstract: The optimized soil penetrating machine is characterized by parameters that are optimized with respect to maximum kinetic energy that the machine cyclically obtains for soil deformation during the forward mode of operation. The optimization of the parameters is based on the author's analytical investigation that revealed the existence of the optimal values of the lengths of the striker and its forward stroke at which the machine's kinetic energy reaches its maximum value, resulting in the maximum performance efficiency. The investigation shows that the optimal value of the length of the striker is shorter than the length of its forward stroke. In the existing machines the striker is longer than its forward stroke. This investigation also shows that the efficiency of the existing machines is about 2.5 times less than for their optimized hypothetical counterparts. Since the existing machines cannot be optimized it is required to implement new design concepts.

Abstract: The optimized pneumatic hammer is characterized by maximum performance efficiency that is achieved due to author's analytical investigations which revealed the existence of the optimal value of the striker's length with respect to maximum kinetic energy of the tool. On the contrary to the existing hammers, in the optimized hammers the length of the strikers is shorter than their strokes. Calculations based on the mentioned investigation show that the kinetic energy of optimized hammers could be about 2.5 times higher than of their existing counterparts. The optimized pneumatic hammer has two modes of operation—the regular mode of operation during which the tool interacts with the target media and the retracting mode of operation for releasing the severely jammed tool from the media. Optimized pneumatic hammers allow for a considerable decrease of their weight and diameters without compromising their performance while making easier the work of the operators.

Abstract: The invention represents a new design of a reversible penetrating machine (90) with a pneumatically controlled differential air distributing mechanism. This design eliminates the springs, the rear anvil assembly, and several other components found in the prior machine. The chisel and the tail of the machine are also redesigned to eliminate the need of a special attachment in case of retracting a failed machine. In addition, a simplified modification of the machine for special applications is disclosed in which the rear valve chest with associated parts is replaced by a single flange having appropriate air ducts. Finally, the new design of the chisel causes a reduction of the lateral friction between the body of the machine and soil. All this significantly increases the reliability and efficiency of the machine and results in decrease of the related manufacturing and operating cost.

Abstract: The invention represents a monotube differential pneumopercussive self-propelled reversible soil penetrating machine with stabilizers (100) having an increased efficiency, reliability, durability, and directional stability, and also a lower cost compared to existing machines. All of these achievements are associated in part with the development of an innovative monotube housing with rigidly secured to its outside surface structurally shaped longitudinal directional stabilizers, creating closed longitudinal air passages between the outside surface of the monotube housing and inside surface of the structurally shaped stabilizers. The invention offers a rigid connection of the air-distributing mechanism without use of any tail nuts, which simplifies the machine and reduces its cost. The chisel assembly is simplified and the overall weight of the machine is reduced.

Abstract: The invention represents a differential pneumopercussive self-propelled reversible soil penetrating machine (100) having essentially higher efficiency, reliability, durability, and controllability compared to conventional machines. All of these achievements are associated in part with the development of an innovative differential air-distributing mechanism (106) which inherently allows for relatively long strokes of the striker (104) resulting in relatively high impact energy of the striker. The operation of this mechanism is based on the difference between the pressures in the two separate nominal (high) and reduced (low) pressure air lines which deliver compressed air to the machine. In order to switch over the machine (100) from the forward to the reverse mode operation or vice versa it is just necessary to adjust properly the pressure in the reduced (low) pressure air line by a conventional air pressure regulator associated with the source of compressed air.

Abstract: A self-propelled, pneumopercussive, cyclic action, ground penetrating machine (200) has decreased energy consumption and increased average working velocity compared to conventional machines. This is obtained in part by a valve-operated air-distribution mechanism (203) having separate forward and reverse compressed air supply lines (35, 37), which mechanism (203) does not limit the length of the forward and backward strokes of the striker (202). This mechanism allows the backward stroke chamber (75) to be connected with the atmosphere during the entire forward stroke of the striker (202). This eliminates generation of an air buffer in the backward stroke chamber (75) and, consequently, the striker (202) does not lose part of its kinetic energy before impact.

Abstract: A self-propelled, pneumopercussive, cyclic action, ground penetrating machine (200) has decreased energy consumption and increased average working velocity compared to conventional machines. This is obtained in part by a valve-operated air-distribution mechanism (203) having separated forward and reverse compressed air supply lines (35, 37), which mechanism (203) does not limit the length of the forward and backward strokes of the striker (202). This mechanism allows the backward stroke chamber (75) to be connected with the atmosphere during the entire forward stroke of the striker (202). This eliminates generation of an air buffer in the backward stroke chamber (75) and, consequently, the striker (202) does not lose part of its kinetic energy before impact.