Motor Piston Movement Modified Relative To Motive Fluid Port Patents (Class 173/17)
  • Patent number: 10189153
    Abstract: A leveling device assembly for use with a hydraulic hammer is provided. The leveling device assembly comprises a control unit, a leveling sensor in communication with the control unit, and a laser generator in communication with the control unit. Additionally, the laser generator is configured to produce a first colored light beam and a second colored light beam different from the first colored light beam. The control unit is further configured to cause the laser generator to produce the first colored light beam when the leveling sensor indicates the hydraulic hammer is in a substantially vertical position and produce the second colored light beam when the leveling sensor indicates the hydraulic hammer is in a substantially non-vertical position.
    Type: Grant
    Filed: March 3, 2017
    Date of Patent: January 29, 2019
    Inventor: Sonny Frank
  • Patent number: 10022850
    Abstract: Provided is a stepless variable auto stroke hydraulic breaker system capable of reducing impact energy reflected in the event of an idle blow by detecting a frequency of vibrations generated when a chisel breaks objects such as bedrocks using a vibration sensor, operating according to a short stroke if the frequency of vibrations does not exceed a preset frequency, and automatically switching the short stroke into a long stroke if the frequency of vibrations exceeds the preset frequency. The breaker system includes a vibration sensor configured to detect vibrations generated when a chisel breaks rocks, a transmitter provided with the vibration sensor and configured to transmit signals generated from the vibration sensor, a receiver configured to receive the signals transmitted from the transmitter, and a stepless variable auto stroke hydraulic breaker controlled by a reception micro controller unit (MCU) of the receiver.
    Type: Grant
    Filed: July 29, 2015
    Date of Patent: July 17, 2018
    Inventors: Won Hae Lee, Hak Kyu Kim
  • Patent number: 9193057
    Abstract: The absorber for a hand machine tool according to the invention with a linear drive has a case and a body of mass moveable alongside of an absorber axis relative to the case. Force is applied toward a first direction to a first coupling element moveable alongside of the absorber axis, which is coupled with the body of mass using a first spring. Force is applied toward a second direction to a second coupling element moveable alongside of the absorber axis using a second spring coupled with the case. With a movement toward the first direction, the first coupling element is frictionally coupled with the second coupling element and with a movement toward the second direction, it is uncoupled from the second coupling element.
    Type: Grant
    Filed: April 20, 2012
    Date of Patent: November 24, 2015
    Inventor: Franz Mossnang
  • Patent number: 9016404
    Abstract: The invention relates to a ram boring device for creating horizontal boreholes, having an impact piston which moves in an oscillatory manner within a casing of the ram boring device and of which the impact frequency or impact intensity can be varied by displacing the center position of the impact piston inside the casing.
    Type: Grant
    Filed: August 20, 2010
    Date of Patent: April 28, 2015
    Assignee: TRACTO-TECHNIK GmbH & Co. KG
    Inventor: Franz-Josef Püttmann
  • Patent number: 8276682
    Abstract: A ball valve assembly for use as a control valve for controlling the flow of gas through a continuous stroke pneumatic tool. The valving element is generally spherical and non-magnetizable. The generally spherical valving element is loosely confined between two concave generally conical surfaces, which are provided on valve seat members. The concave generally conical surfaces are opposed to one another to define a valve chamber therebetween. Sufficient clearance is provided so the generally spherical valving element is free to roll and tumble as it moves in the valve chamber between the concave generally conical surfaces. This allows the ball valve assembly to be self purging of excess lubricant, dust, and the like. Wear is distributed over the entire generally spherical surface of the valving element. The loose confinement is also sufficient to provide a relatively large cross-section of gas passageway through the control valve assembly.
    Type: Grant
    Filed: February 1, 2008
    Date of Patent: October 2, 2012
    Assignee: American Pneumatic Tools, Inc.
    Inventor: Andrew Hall
  • Patent number: 8176995
    Abstract: A method and means of minimizing the effect of elastic valve recoil in impact applications, such as percussive drilling, where sliding spool valves used inside the percussive device are subject to poor positioning control due to elastic recoil effects experienced when the valve impacts a stroke limiting surface. The improved valve design reduces the reflected velocity of the valve by using either an energy damping material, or a valve assembly with internal damping built-in, to dissipate the compression stress wave produced during impact.
    Type: Grant
    Filed: April 16, 2009
    Date of Patent: May 15, 2012
    Assignee: Sandia Corporation
    Inventors: Yarom Polsky, Mark C. Grubelich, Mark R. Vaughn
  • Patent number: 8006776
    Abstract: A pneumatic device control apparatus and method comprising a ported valve slidably fitted over a feed tube of the pneumatic device, and using a compliant biasing device to constrain motion of the valve to provide asymmetric timing for extended pressurization of a power chamber and reduced pressurization of a return chamber of the pneumatic device. The pneumatic device can be a pneumatic hammer drill.
    Type: Grant
    Filed: February 3, 2009
    Date of Patent: August 30, 2011
    Assignee: Sandia Corporation
    Inventor: Yarom Polsky
  • Patent number: 7992652
    Abstract: A fluid distributor cylinder is for a percussive drill assembly that includes a casing having an inner circumferential surface defining a central bore, a central axis extending through the bore, a bit movably coupled with the casing and a piston movably disposed within the casing bore. The distributor cylinder includes a generally tubular body disposeable within the casing bore and having first and second ends, a central axis extending generally between the first and second ends, an outer circumferential surface. At least a section of the outer surface is configured to engage with the inner surface of the casing so to form an interference fit between the body and the casing. The cylinder includes an exterior thread and/or a radially-extending shoulder configured to releasably engage with the casing inner surface so as to substantially prevent axial displacement of the distributor body with respect to the casing.
    Type: Grant
    Filed: February 5, 2009
    Date of Patent: August 9, 2011
    Assignee: Atlas Copco Secoroc LLC
    Inventor: Timothy J. Plunkett
  • Patent number: 7757779
    Abstract: Pressure-air driven percussion device for a down-the-hole drill with a hammer-piston which is axially reciprocally movable in a hammer-piston chamber through a driving device. The hammer-piston in operation acting with a hammer-end against an upper end of a drill bit which is positioned inside a chuck. An air-cushion for reducing percussive power is arranged to be formed at the hammer-end of the hammer-piston in positions where the drill bit has been moved past a predetermined distance in the percussion direction. The drill bit is sealingly slidingly supported in a drill bit bushing, and the hammer-end of the hammer-piston is formed so that it sealingly cooperates with the drill bit bushing in the positions in order to form the air-cushion.
    Type: Grant
    Filed: November 29, 2002
    Date of Patent: July 20, 2010
    Assignee: Atlas Copco Secoroc AB
    Inventors: Torbjörn Jacobsson, Berndt Ekwall
  • Patent number: 7607490
    Abstract: A pneumatic impact tool and method includes a cylinder pipe or housing closed with a cover, as well as an impact piston that forms a first pressure chamber between an impact plate and the impact piston, and a second pressure chamber between the cover and the impact piston. The cover is provided with at least one opening, the surface of which is smaller than the piston surface, whereby the impact piston seals the opening when it is in its fully retracted position.
    Type: Grant
    Filed: June 7, 2006
    Date of Patent: October 27, 2009
    Assignee: Netter GmbH
    Inventor: Thomas Reis
  • Patent number: 7600578
    Abstract: A percussion adapter for a positive displacement motor including a housing, a torque tube and a reciprocating percussive piston operable by application of fluid pressure thereto. The piston can be driven to create a percussive effect by rotary movement of the torque tube. The percussion adapter can have a bypass option to allow flow through the percussion adapter without operation of the piston.
    Type: Grant
    Filed: September 13, 2007
    Date of Patent: October 13, 2009
    Inventor: Dale G. Crooks
  • Patent number: 7469751
    Abstract: A pneumatic hammer comprises an elongate hollow casing with operatively upper and lower ends and has a piston slidingly received within the casing and operable to reciprocate within the casing between upper and lower pressure chambers defined within the casing. The hammer further has an axially displaceable bit assembly at the lower end of the casing and a backend assembly at the upper end of the casing. The piston has a striking face at an end thereof proximate the bit assembly, and the piston is operable to impact on a contact surface of the bit assembly in an impact region of the casing. The hammer is characterized in that the piston is shaped and dimensioned at its proximal end to have a snug sliding fit with an interior of the casing in the impact region of the casing.
    Type: Grant
    Filed: May 12, 2005
    Date of Patent: December 30, 2008
    Inventor: Bernard Lionel Gien
  • Publication number: 20080245541
    Abstract: The invention relates to a percussive tool having an oscillatory drive (3), the force of which is transmitted to a tool bit holder (25) by way of a drive member (17). Extending through the percussive tool is a longitudinal opening that allows a rod-shaped object, such as, for example, a guide wire, to be guided through the percussive tool. The tool bit holder (25) has a seat (34), which can receive the tool bit in different orientations. Moreover, the tool bit holder (25) is made of a combination of light metal and steel, which allows a reduction in acceleration forces and noise generation.
    Type: Application
    Filed: May 17, 2005
    Publication date: October 9, 2008
    Inventor: Daniel Grunig
  • Patent number: 7426965
    Abstract: The invention discloses a fluid-driven impactor, a power transmission mechanism for the impactor and the use of the impactor. In the prior art, the working life of the impactor is short, since a rubber primary seal and an upper fluid-diverging lid for the fluid-driven impactor are both liable to erosion and the efficiency in transmitting power is low due to the complexity of the power transmission mechanism. In order to increase the drilling speed and/or extend the life of the impactor, the side cavity passage is formed in such a way that the inner wall of the outer pipe is isolated from the side cavity passage in a watertight manner without the use of the rubber primary seal. The loss in transmitting power is minimized by integrating the anvil of the power transmission mechanism and the lower joint.
    Type: Grant
    Filed: January 14, 2003
    Date of Patent: September 23, 2008
    Assignees: China Petroleum & Chemical Corporation, Exploration & Production Research Institute, Sinopec
    Inventors: Xinghua Tao, Guoqiang Xu, Xutian Hou, Yijin Zeng
  • Patent number: 7422074
    Abstract: A sleeve carried by and preferably slidable relative to the piston, for controlling air passages associated with a central air feed tube, whereby retraction pressure is applied to the piston substantially at impact. It is the impact itself of the piston against the bit, which enhances sliding of the sleeve relative to the piston, over the feed tube, and thereby switches the airflow at the moment of impact.
    Type: Grant
    Filed: May 19, 2006
    Date of Patent: September 9, 2008
    Assignee: Numa Tool Company
    Inventor: Robert J. Meneghini
  • Patent number: 7422073
    Abstract: The invention relates to a ground working implement and to a method for introducing a working element into the ground, using vibrations. By means of a vibration generator vibrations are generated and transmitted to the working element during its introduction into the ground. According to the invention a gentle vibration generation and transmission are brought about in that the vibration generator has at least one vibrating piston mounted in linearly displaceable manner in a casing spaced from the working element. The vibrating piston is driven in oscillating manner in the casing for generating vibrations. The vibrations are transmitted via the casing to the working element.
    Type: Grant
    Filed: August 31, 2005
    Date of Patent: September 9, 2008
    Assignee: Eurodrill GmbH
    Inventor: Carl Hagemeyer
  • Patent number: 7353890
    Abstract: A down-the-hole hammer includes a casing and a piston movable in the casing between a lowermost operating position and an uppermost operating position. A recess is provided between the piston and the casing so that the piston and the casing define an intermediate chamber between a top end of the piston and a bottom end of the piston. A passageway is provided between a source of pressurized fluid and the intermediate chamber such that, at all positions of the piston between the lowermost and the uppermost operating positions, the source of pressurized fluid is in flow communication with the intermediate chamber through the passageway. An opening in the piston at least partially defines the passageway.
    Type: Grant
    Filed: January 9, 2006
    Date of Patent: April 8, 2008
    Assignee: Sandvik Intellectual Property AB
    Inventor: Matthew Floyd Shofner
  • Patent number: 7051995
    Abstract: A pressure-fluid driven device for generating a reciprocating movement includes a first (5) and a second relatively movable part (3), wherein a working chamber (7) is intended to be alternatively pressurised and depressurised so as to drive the parts in a movement relative to each other when the working chamber is pressurised. A valve arrangement (8) is intended to control the fluid flow into as well as from the working chamber. The inlet into the working chamber (7) is separate from the discharge from the working chamber (7). The invention also concerns a valve arrangement and a pneumatic tool.
    Type: Grant
    Filed: March 1, 2003
    Date of Patent: May 30, 2006
    Inventor: Peter Tornqvist
  • Patent number: 6883618
    Abstract: The lower end portion of a pneumatic impact hammer cylinder has at least one upper fluid passage and at least one lower fluid passage. A U-shaped sleeve is mounted in a circumferential groove in the lower end portion of the piston. The sleeve includes a base, upper and lower legs extending radially outward from the base, and a cavity extending axially between the legs. The sleeve has an axial length that is less than the axial length of the piston groove such that the sleeve is slidably movable within the piston groove between an upstroke position and a downstroke position. The upper fluid passage and the lower fluid passage cooperate with the sleeve cavity, as the piston reciprocates between the impact position and the recovery position, to supply pressure fluid to the impact end of the operating chamber for a portion of each upstroke and each downstroke.
    Type: Grant
    Filed: June 15, 2004
    Date of Patent: April 26, 2005
    Assignee: Numa Tool Company
    Inventor: Jack H. Pascale
  • Patent number: 6827156
    Abstract: An air hammer includes an air hammering mechanism and a vibration suppressing device to absorb the vibration transmitted from the air hammering mechanism. The vibration suppressing device includes a cylinder forming a front channel and a rear channel in communication with each other. First and second air passageways are defined in the cylinder and in communication with the front and rear channels respectively. A valve is movably received in the front channel. The valve defines a bore and third air passageways selectively alignable with the first air passageways. A piston is movably received in the rear channel and forms a projection. A jacket surrounds the cylinder to form therebetween an air chamber that communicates the second air passageways. The jacket has a closed end defining a hole into which the projection is selectively received to block the hole.
    Type: Grant
    Filed: September 22, 2003
    Date of Patent: December 7, 2004
    Inventor: Wen-Liang Hsiao
  • Patent number: 6799641
    Abstract: A fluid channeling device is for a percussive drill including a casing having an interior space, drive and valve chambers defined within the interior space, a piston disposed within the casing and having an upper end disposeable within the drive chamber and a longitudinal through-bore, and a valve for controlling flow into the drive chamber. The device includes a first member partially disposed within the drive chamber so as to extend into the piston bore when the piston end is within the drive chamber. The first member has an outer surface, an interior space and one or more ports extending between the outer surface and interior space and fluidly connectable with the drive chamber. A second member is disposed within the first member interior and has a passage fluidly connected with the valve chamber and fluidly connectable with the port(s) to establish fluid communication between the drive and valve chambers.
    Type: Grant
    Filed: June 20, 2003
    Date of Patent: October 5, 2004
    Assignee: Atlas Copco AB
    Inventors: Leland H. Lyon, Warren Thomas Lay, Jeffrey P. White
  • Patent number: 6702045
    Abstract: There is provided drilling apparatus (10) comprising a hammer casing (11), a free piston motor piston guide and porting sleeve (12), a drive sub (13), a drill bit (15) splined by shank (16) to the drive sub (13). Below the splined portion (17) the drive sub is relieved at (23) to form an annular air space for motor exhaust air from the splines (16) and (17). The drive sub (13) retains a gauge sleeve (24) via an annular flange (25) between the hammer casing (11) at (26) and a shoulder (27) on the drive sub (13). Below the shoulder (27) the outer diameter of the drive sub (13) is provided with eight grooves that form conduits (30) with the lower portion (31) of the gauge sleeve (24) extending parallel to the drill axis in communication with the space (23) via ports (32). The lower portion (31) extends down the side of the drive sub (13) and terminates with it at (34) adjacent the shoulder (33) at the transition from the bit shank (16) and the bit head (35).
    Type: Grant
    Filed: May 31, 2002
    Date of Patent: March 9, 2004
    Assignee: Azuko Party Ltd
    Inventor: John Elsby
  • Patent number: 6609577
    Abstract: A percussive rotational impact hammer assembly for creating high torques. A generally cylindrical piston rotatably mounted on a hammer inside an outer casing oscillates on the hammer and strikes an impact surface on the hammer. The piston and housing have pressurized fluid ports and passageways for conducting pressurized fluid to alternately load an impact-driving chamber and return chamber. The piston is accelerated against the impact surface and the kinetic energy of the piston is transmitted to the hammer transmitting the rotational movement to a member engaged with the hammer, such as a drill bit or other member. The rotational impact hammer assembly can be adapted for use in a downhole hammer, in break out tongs for drill pipe, in wrenches for loosening or tightening nuts and bolts, or in other mechanical devices where high torque is desired.
    Type: Grant
    Filed: September 28, 2002
    Date of Patent: August 26, 2003
    Assignee: Bark International, Inc.
    Inventor: Rainer Sebastiano Beccu
  • Patent number: 6557647
    Abstract: An impact hammer system for driving an elongate member comprising a ram member, a frame assembly, an actuator assembly, and a power source. The ram member defines a ram bore. The frame assembly supports the ram member such that the ram member may move relative to the frame assembly between first and second positions. The actuator assembly is operatively connected between the frame assembly and the ram member and is operable in extended and retracted configurations. At least a portion of the actuator assembly is disposed within the ram bore and a substantial portion of the actuator assembly extends out of the ram bore when the cylinder is in the extended position. The power source is operatively connected to the actuator assembly to place the actuator assembly in the extended and retracted configurations. Extension and retraction of the actuator assembly moves the ram member between the first and second positions, respectively.
    Type: Grant
    Filed: May 29, 2001
    Date of Patent: May 6, 2003
    Assignee: American Piledriving Equipment, Inc.
    Inventor: John L. White
  • Patent number: 6334495
    Abstract: A fluid-operated percussion device (1) having a percussive piston (3), which alternately executes a work stroke and a return stroke due to the effect of a control. To avoid no-load strikes, in one embodiment of the percussion device (1), the percussive piston (3) is shut down if it has overshot the extended position occurring in normal operation (long- and/or short-stroke operation) by a predetermined distance in the work-stroke direction (arrow 3e) and reached a no-load-strike position. For this purpose, the interior (2d) of the work cylinder (2) that receives the percussive piston (3) additionally has a no load-strike opening (20a), which is connected to the pressure line (8) of the percussion device (1) with an interposed safety element (21) that can be switched between an inoperative position and an operative position.
    Type: Grant
    Filed: March 16, 2001
    Date of Patent: January 1, 2002
    Assignee: Krupp Berco Bautechnik GmbH
    Inventors: Thomas Deimel, Marcus Geimer, Marcus Mellwig, Heinz-Jürgen Prokop
  • Patent number: 6131672
    Abstract: A down-the-hole percussive drill comprises a casing, a drill bit mounted at a lower end of the casing, a hollow feed tube fixed within the casing and extending along a center axis thereof, and a piston mounted for axial reciprocation within the casing for transmitting impacts to the drill bit. The upper portion forms a downwardly facing surface at the junction between the upper and lower portions. Passages for conducting lubricant-containing pressurized air are formed in the piston. At least one of those passages constitutes a vertical recess formed in the outer periphery of the piston. The piston includes a radially outwardly projecting rib disposed between upper and lower ends of the recess. Air is blocked from traveling past the rib until the rib becomes located opposite an annular groove formed in an inner surface of the casing.
    Type: Grant
    Filed: February 14, 2000
    Date of Patent: October 17, 2000
    Assignee: Sandvik AB
    Inventors: Rainer Beccu, Matt Shofner, Kenneth Ahlhorn
  • Patent number: 6062322
    Abstract: A down-the-hole percussive drill comprises a casing, a drill bit mounted at a lower end of the casing, a hollow feed tube fixed within the casing and extending along a center axis thereof, and a piston mounted for axial reciprocation within the casing for transmitting impacts to the drill bit. The piston has a stepped configuration in that a lower portion thereof is of smaller outer diameter than an upper portion thereof. The upper portion forms a downwardly facing surface at the junction between the upper and lower portions. Air-conducting passages are formed in the upper portion of the piston and are supplied with pressurized air from the hollow feed tube. One of those passages intersects the downwardly facing surface of the upper portion of the piston. The hollow feed tube is mounted to a top sub of the drill by pins which are mounted in the top sub and extend radially into a sidewall of the feed tube, the pins being situated outside of the central passage.
    Type: Grant
    Filed: June 15, 1998
    Date of Patent: May 16, 2000
    Assignee: Sandvik AB
    Inventors: Rainer Beccu, Matt Shoffner, Kenneth Ahlhorn
  • Patent number: 6050347
    Abstract: An in-hole hammer for boring in ground has an elongated hollow housing carrying an internal striking piston in a piston chamber. An exchangeable boring head is threadably connected to the forward end of the housing and the striking piston impacts against the forward wall of the housing defining the piston chamber to transmit forward driving impact energy to the boring head. A boring rod which urges the hammer forwardly and rotates it about the longitudinal axis is connected to the rear end of the housing through a connecting piece non-rotatably fixed, but slidable relative, to the housing so that the axially directed impact energy produced by the striking piston is not transmitted to the boring rod.
    Type: Grant
    Filed: December 16, 1997
    Date of Patent: April 18, 2000
    Assignee: Terra AG fuer Tiefbautechnik
    Inventor: Dietmar Jenne
  • Patent number: 5992537
    Abstract: A pneumatic downhole impact drill has a backhead for mounting an inlet check valve and a mounting hub for mounting a fluid delivery tube. A split ring has an interior circumferential groove forming upper and lower shoulders and comprises two substantially identical semi-circular ring segments. The ring segments are positioned around flanges on the backhead and the mounting hub such that the upper shoulder of the split ring slidably engages the upper surface of the backhead flange and the lower shoulder slidably engages the lower surface of the mounting hub flange to mount the backhead to the mounting hub. A first gap is formed between the outside surface of the split ring and the inside surface of the casing. A second gap is formed between the inside surface of the groove and the outside surfaces of the mounting hub and backhead flanges. Taken together, the gaps allow lateral relative movement between the mounting hub and backhead flanges.
    Type: Grant
    Filed: May 29, 1998
    Date of Patent: November 30, 1999
    Assignee: Numa Tool Company
    Inventor: Jack H. Pascale
  • Patent number: 5984021
    Abstract: A pneumatic downhole impact drill has a porting system for automatically supplying pneumatic pressure fluid from a fluid delivery tube received within an axial bore in the impact piston to the opposite ends of the piston operating cylinder as the piston reciprocates. A flange on the delivery tube is slidably mounted in a cavity in a mounting hub assembly. Passageways provide fluid communication between the pressure fluid inlet plenum and the operating chamber side of the cavity and between the back chamber and the inlet plenum side of the cavity. Fluid pressure forces acting on the opposite faces of the flange and on the top end surface of the delivery tube reciprocate the delivery tube between upstroke and downstroke positions. Positioning the delivery tube in the upstroke position increases the axial distance that the piston must travel before the pressure fluid supply is connected to the back end of the operating chamber on the piston upstroke.
    Type: Grant
    Filed: January 27, 1998
    Date of Patent: November 16, 1999
    Assignee: Numa Tool Company
    Inventor: Jack H. Pascale
  • Patent number: 5944117
    Abstract: An improved fluid actuated percussive impact tool of the valveless type adapted for down hole drilling is provided. The impact tool includes a casing, a back head, a distributor located at a first end of the casing, and an impact receiving device located at a second end of the casing. A chamber is located between the distributor and the impact receiving device. A cylinder sleeve is located in the chamber adjacent to the distributor. A first pressurized fluid passage is located between the casing and the cylinder sleeve for passing pressurized fluid from the distributor to the chamber. A piston is located in the chamber for reciprocating axial movement. Axially extending ports are located on at least one of the piston, the cylinder sleeve and the casing in the chamber for alternately supplying pressurized fluid to upper and lower chamber portions.
    Type: Grant
    Filed: May 7, 1997
    Date of Patent: August 31, 1999
    Assignee: Eastern Driller's Manufacturing Co., Inc.
    Inventors: Titus H. Burkholder, Duane H. Fetter
  • Patent number: 5887665
    Abstract: The striking element (1) according to the invention serves for the production of shocks which act on a tool. It has a body (3) with a plurality of parallel bores (4). A piston (2), heavy in mass, runs pressure-tight in each of these bores (4) and strikes stops which may be mounted without or within the piston (2). An end space (9) lies at each of the faces of the piston (2). The pistons (2) serve to control the function of the striking element (1). At least one of the pistons (2) produces shocks on the tool. The striking element may execute working shocks in the direction of the tool and, in a special embodiment, execute loosening shocks in the opposite direction. In a special embodiment the magnitude of the energy of loosening shocks may be adjusted or suppressed.The striking element is employed principally in surgery, but also in the general manufacture of apparatus.
    Type: Grant
    Filed: August 19, 1996
    Date of Patent: March 30, 1999
    Assignee: Synthes (U.S.A.)
    Inventors: Hans-Carsten Seifert, Peter Delfosse
  • Patent number: 5875857
    Abstract: A hydraulically operated rock drill including a cylinder, a piston mounted for reciprocating movement in the cylinder, a hydraulic fluid line connected to the cylinder, and an accumulator. A chamber with a section of reduced dimensions is formed in the cylinder, and the piston includes an annular formation which moves within the chamber and into and out of the section as the piston reciprocates. The accumulator is connected via a port to the section, and the hydraulic fluid line is connected to the chamber and is in communication with the accumulator when the annular formation is out of the section and which is cut off from the accumulator, by the annular formation, when the annular formation moves into the section, the annular formation then pressurizing hydraulic fluid in the section whereby hydraulic energy, produced by kinetic energy developed over at least part of a return stroke of the piston, is stored in the accumulator. A second accumulator is connected at least to the high pressure line.
    Type: Grant
    Filed: September 20, 1996
    Date of Patent: March 2, 1999
    Inventors: Jarmo Uolevi Leppanen, Roger Robarts Briggs
  • Patent number: 5860481
    Abstract: A fluid-operated striker assembly includes a working cylinder and a striker piston slidably received in the working cylinder for executing working (forward) and return strokes. The striker piston delivers a blow to a tool bit during the working stroke when the striker piston is either in a limit position or in an advanced position which is beyond the limit position in the direction of the working stroke. A control arrangement applies an alternating fluid pressure to the striker piston to execute the working and return strokes. Further, a precontrol arrangement is provided for affecting the control arrangement dependent on whether the striker piston has exceeded its limit position.
    Type: Grant
    Filed: August 29, 1997
    Date of Patent: January 19, 1999
    Assignee: Krupp Bautechnik GmbH
    Inventors: Heinz-Jurgen Prokop, Karlheinz Fritz, Marcus Geimer
  • Patent number: 5787995
    Abstract: A water driven hammer device has a machine housing and a hammer piston movable to-and-fro in the machine housing. The hammer piston is guided in the machine housing in two guides separated from each other. The guides are formed from two parts each having different inner diameters, and the parts with the largest inner diameters on the guide are turned towards each other. A room between the guides is pressurized and chambers on the other side of the guides are kept at a lower pressure, resulting in fluid flow through the guides for centering the hammer piston in the machine housing to avoid seizure of the hammer piston.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: August 4, 1998
    Assignee: Atlas Copco Rock Drills AB
    Inventors: Berndt Ekwall, Gunnar Wijk
  • Patent number: 5718296
    Abstract: A kind storing energy type of impact control mechanism for pneumatic wrench comprises a flying hammer and a centrifugal valve fitted in the flying hammer, a timing mechanism, a spring, a retaining ring, a limiting device composed of a limiting key-slot on the centrifugal valve and a limiting plunger head with one end sticking into the centrifugal valve chamber and an impact pin. Besides, there are a stretching air duct to make the impact pin stretch and a transition air duct, and a retracting air duct to make the impact pin retract. And on the outer periphery of the centrifugal valve there are a concentric annular slot and an eccentric slot communicating with each other, and another concentric annular spaced apart from them. The above-mentioned structure can raise the controlled air pressure in pneumatic wrench, lower machining difficulty and reduce flying hammer height.
    Type: Grant
    Filed: August 29, 1996
    Date of Patent: February 17, 1998
    Inventor: Lijun Chen
  • Patent number: 5715897
    Abstract: An in-hole rock drilling machine has a hydraulic impact motor within a housing. The hydraulic impact motor has a spool valve contained within a valve housing. The spool valve has two operating positions to alternately pressurize and depressurize a drive chamber to reciprocate a hammer. The spool valve has a continuously pressurized third control surface that biases the spool valve towards a second operating position, a first control surface that acts opposite the third control surface to move the spool valve to a first operating position, and a second control surface that acts with the third control surface to return the spool valve to the second operating position. The valve housing guides the rear portion of the hammer, and a guide bushing guides the front portion of the hammer. The guide bushing, valve housing, and a distance sleeve are clamped against a shoulder of the housing.
    Type: Grant
    Filed: June 12, 1996
    Date of Patent: February 10, 1998
    Assignee: G-Drill AB
    Inventor: Per Gustafsson
  • Patent number: 5605197
    Abstract: A unitary valve assembly for a fluid-activated, percussive paving breaker includes a valve chest having an outer sidewall forming an internal valve chamber, a sidewall within the internal chamber forming a valve bore, a reciprocal valve within the valve bore and a bottom plate permanently fastened to the outer sidewall. The inner sidewall forms a first annular, upstanding sealing seat for the valve, and the bottom plate forms a second annular, upstanding sealing seat for the valve. Passageways through the valve assembly are positioned so as to connect with high and low pressure chambers of a paving breaker, when the valve assembly is inserted into the paving breaker. For weight reduction, the valve assembly is made of acetal resin.
    Type: Grant
    Filed: November 27, 1995
    Date of Patent: February 25, 1997
    Assignee: Ingersoll-Rand Company
    Inventors: Ted C. Chang, Steven W. Bodell, Robert R. Kimberlin, Robert M. Diesel, Scott Barker
  • Patent number: 5573073
    Abstract: A vibration dampened percussive tool has a handle assembly and a cover surrounding a barrel and piston assembly which are caused to oscillate relatively to the handle assembly. The barrel assembly receives a tool retainer and a trigger controls primary air supply. To reduce air consumption when the tool is not actually applied to a workpiece and thereby to reduce exposure of the operator's hand/arm to vibration, an air metering device is provided, which includes a tube slidably mounted in a bush and having a bleed hole in an end of the tube which enters the bush. In one position of the tube within the bush, apertures in the tube are sealed to allow the tool idle and in another position of the tube the apertures are exposed. The tube connects the air line with the piston assembly and moves within the bush responsive to pressure applied by the actual tool on the workpiece.
    Type: Grant
    Filed: January 9, 1995
    Date of Patent: November 12, 1996
    Assignee: Ingersoll-Rand Company
    Inventors: John H. L. Schofield, David A. Hill, Graham Dewhurst, Paul J. Fairhurst
  • Patent number: 5533579
    Abstract: A pneumatic tool includes: a main cylinder having an operating lever for on-off control for the supply of compressed air into the pneumatic tool, a barrel member resiliently coupled to the main cylinder and having a tool unit secured at its front end portion, and an automatically closed throttle valve held in the main cylinder, whereby upon touching on a working object when starting the pounding job, the barrel member will be retracted to open the throttle valve for performing the pneumatic operation by the pneumatic tool; and when subjected to no load condition, the throttle valve will be restored and closed automatically to temporarily stop the pounding of the pneumatic tool to minimize vibration hazard, and an air cushion is inherently formed between the barrel member and the main cylinder for dampening or absorbing the vibration shock of the pneumatic tool.
    Type: Grant
    Filed: October 31, 1994
    Date of Patent: July 9, 1996
    Inventor: Eric Chu
  • Patent number: 5526885
    Abstract: A hydraulic device for driving piles including a casing accommodating a striker with an anvil block, a hydraulic power cylinder, having a rod connected to the striker and a hydraulic directional control selector. A control unit is separated from the directional control selector and is secured on a housing of the power cylinder coaxially with the striker. The hydraulic directional control selector comprises two valves, each of which is provided with two pilot chambers, communication pairwise with each other. The first valve puts the head end of the power cylinder in communication with the rod end, and the second valve establishes communication between the head end and the return flow line.
    Type: Grant
    Filed: February 17, 1995
    Date of Patent: June 18, 1996
    Assignee: Aktsionernoe obschestvo zakrytogo tipa "Rossiiskaya Patentovannaya Tekhnika" (ROPAT)
    Inventors: Viktor A. Kuvshinov, Vladimir M. Ermolaev, Sergei V. Rusin, Vyacheslav A. Goldobin
  • Patent number: 5517740
    Abstract: A tool for removing a metal plug from a tube with repeated pulling impulses includes a pneumatic cylinder defining an interior, cylindrical chamber. A distal end surface of the cylinder defines an anvil. A cylindrical slug, or hammer, is sealingly slidable within the chamber in response to a pressure difference above and below the hammer within the chamber. The cylinder is rigidly connected to the plug so as to hang therefrom, the weight of the cylinder providing a static pull force working in conjunction with the pulling impulses. A pulling impulse is provided by first raising the hammer above the anvil by pneumatically creating a first pressure difference wherein the pressure below the hammer is greater than the pressure above the hammer, then creating a second pressure difference wherein the pressure below the hammer is no greater than the pressure above the hammer in order to drive the hammer against the anvil at speed.
    Type: Grant
    Filed: February 28, 1994
    Date of Patent: May 21, 1996
    Assignee: Westinghouse Electric Corporation
    Inventors: Annette M. Costlow, James J. Roberts, Paul J. Boone, Randall A. Holmes
  • Patent number: 5494116
    Abstract: A pneumatic impact tool useful in pipe insertion operations has a simplified construction as compared to the pneumatic ground piercing tools currently in use for such operations. The body of the tool is a thin walled sleeve clamped between a nose section and an end plate by one or more tying devices such as rigid metal tie rods. This eliminates the need for a thick walled tool body having a tapered nose as is common in existing tools made to move through the soil.
    Type: Grant
    Filed: February 4, 1994
    Date of Patent: February 27, 1996
    Assignee: Earth Tool Corporation
    Inventor: Steven W. Wentworth
  • Patent number: 5485887
    Abstract: The impact tool is provided with a piston (15) oscillating within a cylinder (10). For selecting, with which piston impact surface the piston (15) impacts on the head (7) of a tool holder (2) and accordingly for the selection whether the impact tool generates forward or rearward strikes, respectively, the cylinder (10) is displaced pneumatically between two positions. The displacement occurs depending on the position of a switch (21). This changing of the impact direction is simple and makes it possible to fix the tool holder in the housing (1) making the impact tool sturdy.
    Type: Grant
    Filed: March 22, 1994
    Date of Patent: January 23, 1996
    Assignee: IMT Integral Medizintechnik AG
    Inventor: Georges Mandanis
  • Patent number: 5427187
    Abstract: A method for adjusting the impact force on a hammer operated by a compressible pressure medium utilizes a hammer including a working cylinder having a to-and-fro moving percussion piston and a spindle positioned therein for striking a tool. The working cylinder is positioned inside an outer shell and the spindle is attached to the outer shell. The working cylinder is movable relative to the outer shell and the spindle. A pressure chamber is formed between the working cylinder and the outer shell and pressure medium is fed into or removed from the chamber to adjust the position of the working cylinder relative to the outer shell. In making this adjustment, the strength and frequency of impact of the piston against the opposite end of the spindle is adjusted.
    Type: Grant
    Filed: June 1, 1993
    Date of Patent: June 27, 1995
    Inventor: Valto Ilomaki
  • Patent number: 5402854
    Abstract: A fluid distributor for a debris flushing system in a fluid-activated jackhammer includes a bore through a reciprocal piston, for fluid flow into an exhaust chamber, a fluid distributor removably mounted in the piston bore, the fluid distributor operating by forming passageways through the bore and blocking flow in other portions of the bore. The distributor can have a tapered body that can be severed along its length by the operator to provide a plurality of preselected, fixed flow rates.
    Type: Grant
    Filed: February 17, 1994
    Date of Patent: April 4, 1995
    Assignee: Ingersoll-Rand Company
    Inventors: Robert R. Kimberlin, Duane K. Emerson, Richard S. Holland
  • Patent number: 5392865
    Abstract: Apparatus comprising a striking piston driven hydraulically in a reciprocating fashion by an incompressible fluid inside a cylinder and striking against a tool, of the type in which the piston slides in a cylinder having two concentric piston bearing surfaces of different sections, of which that situated on the tool side has a section smaller than that remote from the tool, the piston and the cylinder delimiting two antagonistic chambers, an annular bottom chamber and a top chamber of larger section.According to the invention the interior of the top chamber is permanently at a regulated pressure of a value intermediate between the inlet or high pressure and the outlet or low pressure, and the annular bottom chamber is connected alternately by a distributor to the high pressure supply circuit during the upward phase of the piston and to the top chamber during the accelerated downward phase of the piston.
    Type: Grant
    Filed: May 28, 1992
    Date of Patent: February 28, 1995
    Assignee: Etablissements Montabert
    Inventor: Bernard Piras
  • Patent number: 5350023
    Abstract: A pneumatic hammer is provided with an adjusting piston (37) dependent on the supply pressure, which adjusts the stroke length of the working piston (16). Thereby, the same pneumatic hammer may be operated both at low and high supply pressures. With high supply pressures, either the early ending of the acceleration phase or the early start of the compression phase or the shortening of the working cylinder shortens the stroke length. Thereby, the pneumatic hammer performs impacts with a substantially constant single-impact energy, regardless of the supply pressure. High supply pressures increase the impact frequency. This results in a considerably improved efficiency at a high drill capacity, a reduced wear and a reduced risk of ruptures of the components of the hammer.
    Type: Grant
    Filed: June 22, 1993
    Date of Patent: September 27, 1994
    Assignee: Ing. G. Klemm Bohrtechnik GmbH
    Inventor: Guenter W. Klemm
  • Patent number: 5325926
    Abstract: A reversible casing for a down-the-hole drill has a predetermined snap ring groove length centered between the casing ends, based upon the casing bore, the snap ring groove depth and the snap ring body length, whereby a snap ring will be retained in the snap ring groove, while permitting lengthwise movement of the snap ring during reverse orientation of the casing.
    Type: Grant
    Filed: February 5, 1993
    Date of Patent: July 5, 1994
    Assignee: Ingersoll-Rand Company
    Inventors: Warren T. Lay, Leland H. Lyon
  • Patent number: RE36166
    Abstract: An air percussion hammer drill is disclosed for operation in an earthen formation. The air compression hammer mechanism comprises a piston that reciprocates while simultaneously rotating within its housing. A hammer drill bit slidably keyed to the bottom of the piston transfers the impact energy to the formation and rotates during operation independent of an attached drill string. The air percussion hammer assembly is therefore ideally suited to directional drilling activities.
    Type: Grant
    Filed: April 24, 1996
    Date of Patent: March 30, 1999
    Assignee: Smith International, Inc.
    Inventors: Roger P. Johns, Michael S. Oliver, Huy D. Bui