Motive Fluid Constantly Applied To One Working Member Face (235) (417) Patents (Class 91/321)
  • Patent number: 10876359
    Abstract: The present invention relates to a hydraulically powered percussion mechanism (12), comprising a piston (6) to impact a percussion bit (8). The percussion mechanism also includes a first accumulator assembly (3a) for hydraulic fluid. The first accumulator assembly comprises a plurality of first accumulator elements (27). In a first aspect, the plurality of first accumulator elements are arranged in a common housing (14). In a second aspect, each of the first accumulator elements is arranged at the same proximity to the piston. In a third aspect, each of the first accumulator elements comprises an accumulator membrane (32) or piston, and wherein the primary direction of movement of the membrane or piston in contact with the hydraulic fluid is substantially parallel to a longitudinal axis of the mechanism.
    Type: Grant
    Filed: June 26, 2014
    Date of Patent: December 29, 2020
    Assignee: MINCON INTERNATIONAL LIMITED
    Inventors: Joseph Purcell, John Kosovich
  • Patent number: 10662741
    Abstract: The present application describes a velocity chamber to regulate a velocity of fluid between an outer diameter of a piston, and an insert to limit, reduce, etc. erosion against the tool and casing.
    Type: Grant
    Filed: April 12, 2019
    Date of Patent: May 26, 2020
    Assignee: COMITT WELL SOLUTIONS US HOLDING INC.
    Inventors: Mohamed Ibrahim Saraya, Roger Antonsen, Peter Kris CLeven
  • Patent number: 8151900
    Abstract: A percussion apparatus driven by a pressurized incompressible fluid includes a body with two coaxial bores for slidably mounting of a tool, and separately slidably mounting a striking piston having a stepped configuration. A control device varies a stroke of the striking piston between a long and a short stroke, and is connected to the directional flow valve and to a bottom chamber of the piston cylinder. The control device includes a cylinder in which a spool is mounted. A first face of the spool is situated in a first chamber permanently subjected to a determined pressure, and a second face of the spool is situated in a second chamber connected to the braking chamber for controlling the varying of the stroke of the striking piston.
    Type: Grant
    Filed: June 27, 2007
    Date of Patent: April 10, 2012
    Assignee: Montabert
    Inventor: Bernard Piras
  • Patent number: 7861641
    Abstract: The invention relates to an impulse generator for a rock breaking tool, the impulse generator (2) comprising a main chamber (4) for receiving a first pressurizeable fluid volume (6), an in the main chamber (4) received impulse piston (8) which is arranged for transfer of pressure energy in the fluid volume (6) into impulses in the tool (10), and a on the side opposite the main chamber (4) side of the impulse piston (8) situated prepressurizing chamber (12) for receiving a second pressurizeable fluid volume (14), where the impulse generator (2) further comprises a on the side opposite the main chamber (4) side of the impulse piston (8) situated pressure relief chamber (16) for receiving a third pressurizeable fluid volume (18), where the relationship between the pressurizing pressures in the fluid volumes (6,14,18) and the relations between the areas of the impulse piston (8) facing the chambers (4,12,16) are such that pressurizing of at least the prepressurizing chamber (12) displaces the impulse piston (8) i
    Type: Grant
    Filed: May 19, 2006
    Date of Patent: January 4, 2011
    Assignee: Atlas Copco Rock Drills AB
    Inventor: Kenneth Weddfelt
  • Patent number: 7677154
    Abstract: In an electrohydraulic control unit for rotor blade adjustment of a wind farm via a hydraulic cylinder, the hydraulic cylinder has one piston chamber and one piston rod chamber. Via an inflow valve assembly, a pressure fluid connection can be established between the pump and the piston chamber, while via an outflow valve assembly, a pressure fluid connection can be established between the piston rod chamber and the tank. Each valve assembly has at least two parallel-connected switch valves, which open and can be closed in various combinations in order to establish a desired position of the hydraulic cylinder. This control unit makes precise regulation of the rotor blade possible.
    Type: Grant
    Filed: March 6, 2007
    Date of Patent: March 16, 2010
    Assignee: Robert Bosch GmbH
    Inventor: Stefan Schmidt
  • Patent number: 7484570
    Abstract: Percussion device including a machine housing (1), a forwards and backwards movable percussion piston (2) in the machine housing, and a reciprocatingly movable tubular valve body (6) inside the machine housing, said percussion piston (2) being arranged to subject a tool (3) to impact, and said percussion piston including a first (4) and a second (5) driving surface arranged to be pressurized in order to drive the percussion piston forwards and backwards, said valve body (6) including a first end surface (12) and a second end surface (13), wherein pressurizing the first end surface (12) tends to drive the valve body in a first direction and pressurizing the second end surface (13) tends to drive the valve body in a second direction, whereby the valve body (6) is arranged, over a channel (7) arranged in the machine housing, to connect at least the second (5) of the driving surfaces alternately to a pressure source (8) or to low pressure (9), wherein an inner room (31) in the tubular valve body (6) is continuous
    Type: Grant
    Filed: September 28, 2005
    Date of Patent: February 3, 2009
    Assignee: Atlas Copco Rock Drills AB
    Inventors: Kurt Andersson, Jörgen Rodert
  • Patent number: 7434503
    Abstract: A percussive apparatus comprises a body inside of which a striking piston is mounted in a cylinder bore. Two axially offset pieces are mounted inside the cylinder bore of the body while being concentric to the piston, and a deformable washer is placed between said pieces. One of the pieces is stationary with regard to the other piece that, however, is mounted in a manner that enables it to slide inside the cylinder bore and to be displaced in the direction of the stationary piece while being subjected to the action of the supply pressure of the hydraulic fluid that acts upon the surface of the moving piece facing away from the side opposite the stationary piece. The displacement of the moving piece causes the elastic washer to deform in order to create a passage with a variable cross-section on the return circuit of the hydraulic fluid to the reservoir or on a circuit that diverts, to the return circuit, a portion of the delivery flow of the apparatus whereby regulating the input pressure.
    Type: Grant
    Filed: December 2, 2004
    Date of Patent: October 14, 2008
    Assignee: Montabert
    Inventor: Jean-Sylvain Comarmond
  • Patent number: 7410010
    Abstract: A hydraulic impact mechanism includes a housing with a cylinder bore, a forward working chamber and a rear working chamber, a hydraulic fluid supply passage connected to the forward working chamber and a drain passage connected to the rear working chamber, a hammer piston reciprocally guided in the cylinder bore for delivering blows to a working implement attached to the housing, a pressure accumulator pre-loaded to a certain pressure level, and a distribution valve for alternatingly connecting the rear working chamber to the supply passage and the drain passage to thereby reciprocate the hammer piston, wherein a sequence valve is provided in the drain passage to keep up the pressure in the rear working chamber so that the resulting forward directed force prevents the piston from being moved backwards in the cylinder bore at pressure levels in the supply passage below the pre-load pressure level of the accumulator.
    Type: Grant
    Filed: August 24, 2005
    Date of Patent: August 12, 2008
    Assignee: Atlas Copco Construction Tools AB
    Inventors: Roland Stig Henriksson, Anders Wilhelm Lundgren
  • Publication number: 20080011154
    Abstract: A pneumatic pump has a valve body having a piston compartment and a receiving compartment, wherein a piston is slidably and sealedly disposed in the valve body to move between a first position and a second position. The valve body also has an exit opening communicating with the piston compartment and a resilient element to help pushing the piston to the first position. An actuator pumps air into the piston compartment and pushes the piston to the second position. The pneumatic pump further has a valve control which has a sealing member sealedly formed at the piston compartment, a driving member which is connected to the exiting opening, wherein a pressure drives the driving member automatically to unseal the sealing member to release the air inside the piston compartment to a releasing cavity and eventually allows the piston to move back to its original position.
    Type: Application
    Filed: November 29, 2006
    Publication date: January 17, 2008
    Inventors: Shuyong Kong, Lingyu Song, Jihui Wang
  • Patent number: 7311502
    Abstract: A method for supplying solvent to an ultra-high pressure liquid chromatography system using a hydraulic amplifier. The hydraulic amplifier system includes a hydraulic cylinder comprising a primary piston chamber in which a primary piston is disposed and a secondary piston chamber in which a secondary piston is disposed. The cross-sectional area of the primary piston is larger than the cross-sectional area of the secondary piston. The difference in the cross-sectional areas of the pistons creates an amplification of the pressure in the primary piston chamber and a reduction in flow rate.
    Type: Grant
    Filed: March 1, 2004
    Date of Patent: December 25, 2007
    Assignee: Waters Investments Limited
    Inventors: Geoff C. Gerhardt, Bruce J. Compton
  • Patent number: 7178447
    Abstract: The invention relates to a control valve, a percussion device and a method of controlling a working cycle of a percussion device. A percussion device (1) for breaking rock includes an impact element (8) controlled by a control valve (2). The control valve includes a control element (5) arranged to control channels (7b) leading to a working pressure surface (9) of the impact element (8). The control element, during a working cycle of the control valve, is arranged to open and close pressure channels at several connecting moments so that during one working cycle of the valve, several impact pulses are arranged to be produced.
    Type: Grant
    Filed: February 23, 2004
    Date of Patent: February 20, 2007
    Assignee: Sandvik Tamrock Oy
    Inventors: Antti Koskimäki, Markku Keskiniva, Jorma Mäki, Mauri Esko, Erkki Ahola, Aimo Helin
  • Patent number: 7174824
    Abstract: The invention relates to a control valve, a percussion device and a method of controlling a working cycle of a percussion device. The percussion device (1) used for breaking rock comprises an impact element (8), which is controlled by a control valve (2). The control valve comprises a control element (5), which is arranged to control channels (7b) leading to a working pressure surface (9) of the impact element (8). The movement of the control element to its extreme position is arranged to form a closed pressure space, where pressure medium compresses and converts kinetic energy of the control element into pressure energy. The pressure energy is re-converted into kinetic energy and utilized when the control element changes its direction.
    Type: Grant
    Filed: February 23, 2004
    Date of Patent: February 13, 2007
    Assignee: Sahdvik Tamrock Oy
    Inventors: Antti Koskimäki, Markku Keskiniva, Jorma Mäki, Erkki Ahola
  • Patent number: 7147442
    Abstract: An automatic oil pump includes a drive chamber, having a reciprocal driving device, and an oil chamber, having a sucking device, located on two sides of a main body. The reciprocal driving device has a piston unit having a valve chamber at its center and a balance valve and is pushed by a spring. The drive chamber has grooves on its inside wall. The piston unit has two channels, allowing air to flow into the valve chamber past two sides of the piston unit. On the piston unit is a driving rod. The driving rod penetrates into the main body and reaches into the oil chamber. A hermetic cover and a movable piston are attached to an end of the driving rod. On the wall of the piston are pluralities of through holes. The reciprocal driving device drives the piston in the oil chamber to move reciprocally, so oil is sucked into and out of the oil chamber continuously. Thereby, oil sucking speed and volume are upgraded to save time and labor, and oil pumping efficiency is enhanced.
    Type: Grant
    Filed: May 22, 2003
    Date of Patent: December 12, 2006
    Inventor: Kuo-Chung Yeh
  • Patent number: 6971301
    Abstract: An asymmetrical vibrator is provided, which is actuated by compressed air. The vibrator operates in a case, which has two bores disposed parallel on opposite sides of the casing. One of the bores is smaller than the second bore and the piston operating in the small bore is called the slow piston, since it is actuated with air to a relatively slow motion and the piston operating in the second larger bore is called the fast piston, since it is moves at a larger speed when driven directly by the compressed air. The asymmetric vibration motion can be employed to transport materials upwardly in factories and assembly stations. The air operated asymmetric vibrators need low maintenance and do not entail the spark dangers caused by the presence of electrical wiring for electrical drive motors.
    Type: Grant
    Filed: November 10, 2003
    Date of Patent: December 6, 2005
    Assignee: vibro Industries, Inc.
    Inventor: Leroy A. Johnson
  • Patent number: 6829975
    Abstract: A percussive hydraulic apparatus includes a body inside which is mounted a cylinder in which an impact piston is guided. Fluid distribution providing the motion of the piston is produced by a distributor housed in a distribution box mounted in the body. The cylinder and the distribution box are entirely contained in the enclosure defined by the body, with the cylinder being mechanically supported by one of its ends of the body. The distribution box is mounted coaxial to the cylinder and is mechanically supported thereon. Surfaces perpendicular to the axis of the apparatus, subjected to pressure, are arranged and dimensioned such that the resultant hydraulic forces applied on the cylinder and distribution box during all the phases of the operating cycle thereof are directed in the same direction towards a support located in the body of the apparatus.
    Type: Grant
    Filed: January 13, 2003
    Date of Patent: December 14, 2004
    Assignee: Montabert S.A.
    Inventor: Bernard Piras
  • Patent number: 6712587
    Abstract: A hydraulic amplifier system for an ultra-high pressure liquid chromatography system. The hydraulic amplifier system includes a hydraulic cylinder comprising a primary piston chamber in which a primary piston is disposed and a secondary piston chamber in which a secondary piston is disposed. The cross-sectional area of the primary piston is larger than the cross-sectional area of the secondary piston. The difference in the cross-sectional areas of the pistons creates an amplification of the pressure in the primary piston chamber and a reduction in flow rate.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: March 30, 2004
    Assignee: Waters Investments Limited
    Inventors: Geoff C. Gerhardt, Bruce J. Compton
  • Patent number: 6415704
    Abstract: A pneumatic oil pump has a cylinder, a piston, a pedal and an oil reservoir. The cylinder has a central bore, a sealed front end and a sealed rear end. An air connector is mounted in a cover on the front end of the cylinder. An actuating valve is mounted in the cover on the front end of the cylinder and communicating with the air connector and the central bore of the cylinder. The piston is movably mounted in the bore of the cylinder to divide the central bore of the cylinder into a first chamber and a second chamber. A piston seat is attached to the piston at an end facing the rear end of the cylinder. A ventilative, sound-absorbing material is arranged between the air outlets of the piston and the piston seat. By such an arrangement, the shock of the air flow can be absorbed by the ventilative, sound absorbing material. Therefore, noise and shock will not occur when the pneumatic pump is in operation.
    Type: Grant
    Filed: January 4, 2001
    Date of Patent: July 9, 2002
    Inventor: Ta-Chin Wang
  • Patent number: 6152013
    Abstract: A hydraulically actuated breaker with a lost-motion preventing device includes a cylinder portion (26) defining a first chamber (23) constantly communicated with a hydraulic pressure source (47) and having a small pressure receiving area for upwardly moving a piston (22) and a second chamber (24) having a large pressure receiving area for downwardly moving the piston, by inserting the piston into a piston bore (21) of a breaker main body (20); a chisel (28) inserted within a chisel insertion hole (27) of the breaker main body in opposition to the piston; a main switching valve (40) being switched between a first position (E) communicating the second chamber with a tank (48) and a second position (F) communicating the second chamber with the hydraulic pressure source; and a valve mechanism (30) placing the main switching valve at the first position when the piston is in an effective lower stroke end position, placing the main switching valve at the second position when the piston is in an effective upper strok
    Type: Grant
    Filed: December 7, 1998
    Date of Patent: November 28, 2000
    Assignee: Komatsu Ltd.
    Inventors: Shigeru Shinohara, Mitsuru Arai, Takayuki Muto, Naoki Ishizaki
  • Patent number: 5979291
    Abstract: A hydraulically operated percussion hammer comprising a percussion piston that reciprocates by means of the pressure of the pressure fluid, a main valve that is controlled by the position of the percussion piston and that guides the pressure fluid to the percussion piston in order to provide a reciprocating motion, and a pressure control valve that is placed in an outlet duct for pressure fluid and that prevents the flow of the pressure fluid from the percussion apparatus before the pressure of the pressure fluid in the inlet duct exceeds the set value of the pressure control valve. The percussion apparatus comprises a separate by-pass duct which allows the pressure fluid to flow from the pressure chamber of the percussion piston past the pressure control valve to the outlet duct until the percussion piston has reached a certain point during its return motion.
    Type: Grant
    Filed: July 15, 1997
    Date of Patent: November 9, 1999
    Assignee: Tamrock Oy
    Inventor: Esko Juvonen
  • Patent number: 5890548
    Abstract: Hydraulic percussion hammer, in which a motion of a percussion piston (1) is controlled by a main valve (3), the control motion of which is controlled by a separate control valve (9) in such a way that the main valve changes its state, when the pressure acting on the control valve (9) rises to a predetermined value. The percussion hammer comprises a controller (21) mounted in its return duct (13), by which controller an outflow of pressure fluid from the percussion hammer can be adjusted in such a way that the filling rate of a pressure accumulator (7) and thus the length of a return motion of the percussion piston (1) are proportional to the flow resistance provided by the controller (21).
    Type: Grant
    Filed: June 24, 1996
    Date of Patent: April 6, 1999
    Assignee: Bretec Oy
    Inventor: Esko Juvonen
  • Patent number: 5794717
    Abstract: A rock drill with a percussion mechanism which includes a piston, a body in which is formed a chamber, at least a first cylinder which is located in the chamber and which, on an inner side, forms at least part of a sleeve for the piston, and a valve, for controlling movement of the piston, which is located on an outer side of the first cylinder. A stop structure integrally attached to the first cylinder prevents the valve from being removed.
    Type: Grant
    Filed: October 20, 1995
    Date of Patent: August 18, 1998
    Inventors: Roger Robarts Briggs, Jarmo Uolevi Leppanen
  • Patent number: 5765462
    Abstract: A web cutting device for cutting a web in which a an actuator acts upon a cutter blade so as to produce the cutting stroke. The actuator includes several cylinders placed inside a container or alternatively a number of cylinders placed individually in a plurality of containers. Each of the cylinders includes a piston and a piston rod, the piston rods being attached to the cutter blade with a certain spacing along the length of the cutter blade in a direction transverse to the running direction of the web.
    Type: Grant
    Filed: April 26, 1996
    Date of Patent: June 16, 1998
    Assignee: Valmet Corporation
    Inventor: Aaron Mannio
  • Patent number: 5653369
    Abstract: A pneumatically operated driving device is constructed and arranged to operate in a single actuation sequence and an automatic actuation sequence. The device includes an improved control valve assembly for communicating reservoir pressure to move a piston in a direction to effect a drive stroke of a fastener driving element and for permitting the piston to move in a direction to effect the return stroke of the fastener driving element. The control valve assembly includes a main valve, a secondary valve, and first and second actuating members for controlling movement of the main and secondary valves, a trigger member for moving the actuating members, and trigger member adjustment structure constructed and arranged to adjust pivotal movement of the trigger member thereby providing operator selection of single actuation followed by automatic actuation of the device, or automatic actuation thereof only. The control valve assembly may be removed from the device as a unit.
    Type: Grant
    Filed: November 16, 1995
    Date of Patent: August 5, 1997
    Assignee: Stanley-Bostitch, Inc.
    Inventor: Brian M. White
  • Patent number: 5628444
    Abstract: A control module for a pneumatically operated fastener driving device is constructed and arranged to be mounted with respect to a main frame portion of the device housing so as to open a passageway to operate the device.
    Type: Grant
    Filed: November 16, 1995
    Date of Patent: May 13, 1997
    Assignee: Stanley-Bostitch, Inc.
    Inventor: Brian M. White
  • Patent number: 5626016
    Abstract: The invention provides a vibrator which may be used to vibrate industrial apparatus such as a conveyor, hopper, bin, screen, shaker table, or to agitate a fluid. The vibrator has a element comprising a concave outer skin on one side and a convex outer skin on the other side which define between them a cavity. The cavity is connected to a hydraulic driving circuit which provides a continuous series of high pressure pulses. Each pulse causes the deformable element to change shape. The continuous application of a series of pulses causes the deformable element to continuously vibrate. The high pressure pulses are generated by creating a water hammer within a conduit by means of a valve which can be rapidly opened and closed to allow fluid to flow through the conduit and then suddenly block the fluid flow. The vibrating apparatus may be used to shake industrial structures such as shaking screens, shaking tables, hoppers, bins or the like.
    Type: Grant
    Filed: October 26, 1994
    Date of Patent: May 6, 1997
    Inventor: Bruno H. Walter
  • Patent number: 5492556
    Abstract: A method and apparatus for powering a fluid pump (P) for circulation of a regenerated liquid absorber from a treating vessel or regenerator (R) to a liquid/gas contacting vessel (T) where the liquid absorber removes a predetermined component from a gas. The fluid pump (P) is driven by a shaft from fluid motor (M) and an auxiliary electric motor (E, E-1) assisting the fluid motor (M). The fluid pump (P) receives the entire output of regenerated liquid absorber from the regenerator (R) for pumping the regenerated liquid absorber to the contacting vessel (T). A bypass fluid conduit (49, 48) is utilized for initial circulation of glycol during the start up operation. A glycol measuring device (42) is effective for removing trapped air in conduits (18, 15) between the reboiler (R) and the contactor (T), and in bypass conduits (48, 49) in addition to measuring the flow rate for the liquid absorber.
    Type: Grant
    Filed: October 25, 1994
    Date of Patent: February 20, 1996
    Assignee: Rotor-Tech, Inc.
    Inventor: Richard H. Garrett
  • Patent number: 5370037
    Abstract: The present invention relates to a valve control apparatus for operating a working piston, comprising a main valve spool including a smaller piston face subjected to compressed air from a reservoir and a larger piston face facing a main control space, further comprising an auxiliary valve spool having a first effective area which can be connected by a trigger valve to atmosphere or to a compressed air reservoir to displace the main control spool into an open position, and having a second effective area which is connected to a piston stroke chamber for displacing the main valve spool into a closed position, wherein the auxiliary valve spool is returned when the pressure acting on its second effective area falls below a predetermined value, wherein this effective area is connected to a shift valve which communicates with atmosphere when the trigger is not actuated and which is closed when being actuated and wherein the trigger is provided to move a first length of travel and a second length of travel to actuate
    Type: Grant
    Filed: November 16, 1993
    Date of Patent: December 6, 1994
    Inventors: Joachim Bauer, Klaus Albrecht, Rolf Krahmer
  • Patent number: 5261311
    Abstract: The invention relates to a reciprocating hydraulic motor having a differential piston interposed between an inlet pipe for fluid at a pressure P1 and an exhaust pipe for fluid at a pressure P2 which is less than the pressure P1 The moving assembly constituted by the different-section pistons that slide in a stepped cylinder includes a flap having two positions and controlling three ports, the flap being mounted to pivot about an axis. In each of its positions, the flap bears against two wall portions disposed on opposite sides of the flap and at different distances from the pivot axis so that the effect of the pressures P1 and P2 on the faces of the flap is to establish a positive closure torque.
    Type: Grant
    Filed: July 16, 1992
    Date of Patent: November 16, 1993
    Assignee: Societe Civile De Recherche Sam
    Inventor: Philippe Cloup
  • Patent number: 5222425
    Abstract: This invention relates to a cyclic hydraulic actuator, and more particularly to an actuator for a rock drill and includes: a housing; at least two chambers in the housing; a fluid passage between a first of the chambers and the outside of the housing for feeding a liquid at supply pressure to the chamber during operation of the actuator; a fluid passage between a second of the chambers and the outside of the housing for exhausting liquid from the second chamber during operation of the actuator; a piston reciprocable on an axis in at least the first and second chambers with the piston including an exposed piston area in each of the two chambers for causing, with the liquid at supply pressure, reciprocation of the piston; an inlet valve for opening and closing the second chamber to liquid at supply pressure in the first chamber; an exhaust valve for opening and closing the exhaust passage; the inlet and exhaust valves, chambers and exposed piston areas being so arranged that during cyclic operation of the actua
    Type: Grant
    Filed: January 6, 1992
    Date of Patent: June 29, 1993
    Assignee: Novatek Drills (Proprietary) Limited
    Inventor: Michael R. Davies
  • Patent number: 5209152
    Abstract: An air operated reciprocating piston pump having a differential area piston is provided with an annular shaped airfoil device having a chevron cross-section and which is located beneath the bottom air intake plate to utilize increasing air velocity at the initiation of bottom changeover in order to assure more reliable changeover.
    Type: Grant
    Filed: March 31, 1992
    Date of Patent: May 11, 1993
    Assignee: Graco, Inc.
    Inventor: Andrew M. Olson
  • Patent number: 5188015
    Abstract: An automatically sequenced hydraulic cylinder mechanism, including a hydraulic cylinder having a piston rod which is attached to a working member. The hydraulic system includes a pump which supplies hydraulic fluid to opposite sides of the cylinder. Due to the differential in surface area on opposite sides of the piston, the piston is moved in a direction to extend the piston rod. When the piston bottoms out in its stroke of travel, the pressure in the system is increased and the increased pressure will operate a three-position valve to decrease the pressure in one end of the cylinder and automatically retract the piston rod. The cylinder is thus automatically sequenced to extend the piston rod and retract the piston rod without the use of auxiliary switched or sensors.
    Type: Grant
    Filed: December 26, 1991
    Date of Patent: February 23, 1993
    Assignee: Kelley Company, Inc.
    Inventor: Martin P. Hageman
  • Patent number: 5174387
    Abstract: A control system for a hydraulic percussion mechanism (6) is based on the continuous measurement of the striking rate (z) of the striking piston, or on the continuous measurement of the striking rate (z) of the striking piston together with the quantity per unit time (Q.sub.e) of the hydraulic driving medium coming into the percussion mechanism (6). One, or possibly both, of these parameters is measured from outside the percussion mechanism itself. The control system is configured in such a way that the internal resistance of the percussion mechanism or the hydraulic pump which powers it is increased if there is an increase in the striking rate (z) or the ratio z/Q of the striking rate to the incoming stream rate beyond respective limit values.
    Type: Grant
    Filed: November 20, 1991
    Date of Patent: December 29, 1992
    Assignee: Krupp Maschinentechnik Gesellschaft mit beschrankter Haftung
    Inventors: Friedrich K. Arndt, Robert-Jan Bartels, Heribert Vielhaber
  • Patent number: 5170691
    Abstract: A continually operating fluid pressure amplifier having a reciprocating piston system comprising a broad low pressure piston and a narrow high pressure piston, of which the latter, together with its piston cylinder, is arranged as a three-way pilot valve for operating a bistable control valve that controls the reciprocation of the piston system. The control valve has a primary valve slide controlling the said reciprocation and an auxiliary slide operable to open and close relevant conduit connections for initial amplification of the shift control signals governing the operation of the control valve, whereby a very safe operation of the entire system is ensured. Also ensured is a rapid return stroking of the piston system, such that the produced high pressure can be maintained substantially constant.
    Type: Grant
    Filed: August 15, 1990
    Date of Patent: December 15, 1992
    Inventor: Johannes V. Baatrup
  • Patent number: 5150643
    Abstract: An actuator is driven in a first direction by equal working fluid pressures acting on different piston areas acting in opposite directions, and is driven in a second direction by applying equal pressures on both sides of one of the piston areas. Working fluid from an inlet port, acting in a working fluid chamber, pushes up a valve plate, closes ventilation holes and opens working fluid discharge holes, thereby permitting the working fluid to push the piston upward. Working fluid contained in the working fluid chamber is exhausted from working fluid discharge holes to the outside of the system through a working fluid discharge pipe. When the upward movement of piston reaches its limit, a valve plate is pushed by a spring, thereby causing simultaneous closing of the working fluid discharge holes and the opening of the ventilation holes. As a result of the opened ventilation holes, working fluid pressures in a lower working fluid chamber and an upper working fluid chamber become equal.
    Type: Grant
    Filed: October 22, 1990
    Date of Patent: September 29, 1992
    Assignee: Kabushiki Kaisha Yamada Corp.
    Inventor: Seiji Saita
  • Patent number: 5076140
    Abstract: A hydraulic positioning means is provided which includes means for selectively allowing or prohibiting the flow of the first hydraulic fluid under the operating pressure. It also includes means in the hydraulic positioning means for selectively positioning the workpiece to a plurality of predetermined locations for performing work operations thereon in response to allowing or prohibiting the flow of the first pressurized hydraulic fluid under the operating pressure. Means are also furnished for supplying the first pressurized fluid under the operating pressure to the hydraulic positioning means for such selective positioning of the workpiece. First fluid conduit means transfer the first pressurized fluid at said operating pressure from the pressurized fluid supply means to the hydraulic positioning means. A hydraulic impact load cushioning means is also bifurcatedly provided.
    Type: Grant
    Filed: December 18, 1990
    Date of Patent: December 31, 1991
    Assignee: Pacific Fluid Systems, Corp.
    Inventors: Stanley D. Nelsen, James I. Ott
  • Patent number: 5038668
    Abstract: The invention relates to a hydraulic striking mechanism including a cylinder, a percussion piston guided therein and a piston return device which is supported on the percussion piston and is displaceable independently thereof and can be connected on its side facing the percussion piston tip alternatingly to a pressure source or a pressure-free return conduit. The piston return device is configured as an annular piston which is freely displaceable along the percussion piston and the cylinder and forms therewith a piston chamber. The percussion piston has an abutment face at its end remote from the percussion piston tip which cooperates with the annular piston for moving percussion piston in the return stoke direction. The percussion piston, together with the cylinder, defines an oil chamber which axially follows the piston chamber in a spaced relationship. The percussion piston is provided with a cylindrical shoulder within the oil chamber which determines its end position during the return stroke.
    Type: Grant
    Filed: April 20, 1990
    Date of Patent: August 13, 1991
    Assignee: Krupp Maschinentechnik GmbH
    Inventors: Friedrich-Karl Arndt, Robert Bartels
  • Patent number: 5031402
    Abstract: A wellhead mounted pneumatic actuator for bottom hole oil pumps designed for operation by compressed air or gas. The preferred embodiment utilizes a single action cylinder with the downstroke actuated by the weight of the sucker rods and the fluid contained therein. Sufficient relatively high pressure air or gas from an external source is supplied under the piston of the cylinder to lift the piston at all times. A pressure or solenoid control floating piston bleeder valve selectively routes air or gas into the power cylinder on both sides of the piston to accomplish the downstroke. First and second contactors are mounted to cables suspended from a spreader reciprocating with the piston to contact respective first and second pivot arms to pivot the pivot arms into engagement with the respective first and second activator buttons of the bleeder valve to shift the bleeder valve from one position to the other to effectuate the selective routing of air or gas to the top of the piston as well as under the piston.
    Type: Grant
    Filed: August 2, 1990
    Date of Patent: July 16, 1991
    Inventor: Joseph H. Klaeger
  • Patent number: 4919039
    Abstract: A turning gear is used to rotate a turbine rotor under conditions where it is heating up or cooling down without sufficient motive fluid to cause it to rotate. The turning gear avoid the occurence of a thermal bow. A hydraulic turning gear is disclosed for application in confined areas where a substantial force is required to provide rotation to the rotor. A booster cylinder is used to elevate low pressure fluid for use in a reduced diameter hydraulic cylinder. A ratchet wheel and pawl mechanism uses an adjustable friction force to withhold the pawl from the ratchet wheel after initial contact and further employs a stationary guide rail to reset the pawl for the next contact.
    Type: Grant
    Filed: July 25, 1988
    Date of Patent: April 24, 1990
    Assignee: General Electric Company
    Inventor: Norman E. Nutter
  • Patent number: 4879943
    Abstract: This invention relates to an air motor having a snap-acting overcentering spring mechanism for snapping the valving of the air motor between first and second positions as the piston completes each stroke in the cylinder to ensure reliable stall-free operation of the motor.
    Type: Grant
    Filed: May 17, 1988
    Date of Patent: November 14, 1989
    Assignee: McNeil (Ohio) Corporation
    Inventor: Ayzik Grach
  • Patent number: 4870890
    Abstract: A fluid energized double acting motor is provided for use as the drive for reciprocating mechanisms such as paint pumps for airless spray painting. A piston within the pump housing is moved by pressurized fluid controlled by an automatic reversing valve including spaced check valves. The check valves are selectively seated and unseated by a spring biased piston and fluid pressure controlled valve actuator assembly. The reversing valve system includes anti-stalling features and is of single, low cost, field repairable nature. The motor system also includes features to prevent chattering oscillation due to abrupt changes in motor load.
    Type: Grant
    Filed: August 22, 1988
    Date of Patent: October 3, 1989
    Inventor: Philip L. Cowan
  • Patent number: 4807514
    Abstract: A differential hydraulic jack with a damping system for the control of electric circuit-breakers is provided with a floating ring which produces a damping action at the end of travel and is also provided with a damping extension stud which forms part of the jack piston and penetrates into the damping ring. No provision is made on the jack piston for any packing ring forming a seal with the jack cylinder. The damping ring carries two projecting lips constituting a double valve which forms a leak-tight seal with the bottom face of the jack piston and the internal face of the cylinder end. At the end of the travel of the piston, the damping ring forms a double sealing valve for shutting-off the supply/drain orifice of the jack.
    Type: Grant
    Filed: April 4, 1988
    Date of Patent: February 28, 1989
    Inventor: Claude A. Gartzmuller
  • Patent number: 4807515
    Abstract: An airfoil deicer and method for deicing an airfoil wherein the deicer has an outer skin having an elevated modulus of elasticity and a means for introducing a small deflection into the outer skin thereby creating substantial chord-wise tension in the outer skin, the deflection being induced in less than 0.250 seconds. In the method of deicing, the deflection is induced periodically and being completed within a time span of about 0.250 seconds to remove accumulations of ice as thin as 0.06 centimeters.
    Type: Grant
    Filed: April 3, 1987
    Date of Patent: February 28, 1989
    Assignee: The B. F. Goodrich Company
    Inventors: James A. Briscoe, James C. Putt, Ronald W. Phillips, II
  • Patent number: 4800797
    Abstract: A hydraulic percussion device comprises a housing defining a longitudinal cylinder, a piston longitudinally reciprocal in the cylinder and subdividing same into a front compartment and a rear compartment, and a tool engageable longitudinally with the piston at the front compartment. The compartments are alternately and oppositely hydraulically pressurized to move the piston forward to strike the tool while traveling at an end speed and to move the piston backward away from the tool, the rate of alternation being a frequency parameter and the speed being a force parameter. A controller varies at least one of the parameters by detecting how much the piston rebounds from the tool after striking same and operating the control means in accordance with how much rebound is detected. How much the piston rebounds can be detected by sensing the pressure in one of the compartments immediately after the piston strikes the tool.
    Type: Grant
    Filed: August 7, 1987
    Date of Patent: January 31, 1989
    Assignee: Etablissements Montabert
    Inventor: Jean S. Comarmond
  • Patent number: 4798125
    Abstract: This invention pertains to a pneumatic mode under which the structure of a hydraulic system is driven, particularly denoting the pneumatic mode under which a mini air compressor is being used as a means to elevate a hydraulic jack.This invention makes use of a working lever and a working body attached to the hydraulic mechanism which is compactly closed inside a body to drive the hydraulic lever of the hydraulic mechanism which is compactly closed at the other end of the body to conduct a continuous backward/forward movement which will press against and elevate the hydraulic jack. Such a movement is similar to a continuous backward/forward movement conducted by a piston in a cylinder body. However, the entire structure and effected of this invention is found much better because of its easy fabrication and its function of elevating the hydraulic jack by means of a pneumatic mode, which saves both time and strength and thus meet the requirement of a simple and automatic operation.
    Type: Grant
    Filed: November 3, 1987
    Date of Patent: January 17, 1989
    Inventors: Fung M. Chang, Chien C. Hsu, Wen C. Chen
  • Patent number: 4796428
    Abstract: A double-acting accelerated forging hammer and method of operation are disclosed. The hammer is of the type having a vertically oriented cylinder, a piston slidably mounted within the cylinder having a downwardly depending piston rod extending along the cylinder and attached to a hammer. A gas accumulator communicates with the cylinder above the piston for supplying gas under pressure thereto during a forging stroke, and a fluid accumulator communicating with the cylinder below the piston for supplying fluid thereto at a higher pressure than the gas to dirve the piston upwardly during a return stroke. A fluid tank supplies fluid to recharge the accumulator and receives fluid from the cylinder during the forging stroke. Variable valves control the rate of fluid flow from the cylinder and thereby control the rate at which the piston descends within the cylinder.
    Type: Grant
    Filed: January 17, 1983
    Date of Patent: January 10, 1989
    Assignee: Oilgear Towler, Inc.
    Inventor: Richard W. Hall
  • Patent number: 4785997
    Abstract: An improvement in a hydraulic motor for use with an airless paint sprayer system which includes releasable stop means that lock a spool means within said motor to a surrounding sleeve which stop means signal the end of upper and lower strokes of a reciprocating piston associated with said sleeve. In addition, hydraulic fluid anti shock means are provided to prevent the rupture of outlet filter means.
    Type: Grant
    Filed: November 2, 1987
    Date of Patent: November 22, 1988
    Assignee: Durotech Co.
    Inventors: Miroslav Liska, Anthony Tomsicek
  • Patent number: 4784228
    Abstract: An impact device that consists of a housing having a bore, a piston, and a change-over valve for control of the reciprocal movement of the piston is presented in the present invention. In the present invention, it is not necessary to employ a long-size piston and a high piston speed is obtained and, further, a compact device in which the fluctruation of the pressure in the low pressure path is small can be obtained.
    Type: Grant
    Filed: September 9, 1987
    Date of Patent: November 15, 1988
    Assignee: Teisaku Co., Ltd.
    Inventor: Ikuo Ito
  • Patent number: 4745981
    Abstract: A hydraulic impact tool having a housing, a working tool, a ram, an energy storage device, and a valve slide. The tool also has a high pressure hydraulic fluid inlet port, an intermediate pressure hydraulic fluid inlet port, and two return lines. One of the return lines is for exhausting fluid from an upper annular chamber, and the other return line is for exhausting fluid from an intermediate annular chamber.
    Type: Grant
    Filed: July 30, 1985
    Date of Patent: May 24, 1988
    Assignee: Consolidated Technologies Corp.
    Inventor: Robert J. Buske
  • Patent number: 4674397
    Abstract: The fluid-powered, reciprocating motor includes a cylinder having an inlet chamber and an outlet chamber, a differential area piston mounted in the cylinder, and an output or power shaft connected to the piston. A pressurized fluid, either a gas or a liquid, is continuously introduced into the cylinder inlet chamber and acts on the smaller piston area to move the piston in one direction. A small stream of the fluid flows from the cylinder inlet chamber into the cylinder outlet chamber through a control passage in the piston and is exhausted from the cylinder outlet chamber through an outlet passage until the piston is moved far enough for a valve member carried by the piston to close the outlet passage. Fluid pressure subsequently building up in the cylinder outlet chamber acts on the larger piston area and moves the piston in the opposite direction.
    Type: Grant
    Filed: February 21, 1985
    Date of Patent: June 23, 1987
    Inventor: Thomas J. Wilcox
  • Patent number: 4635531
    Abstract: A hydraulically operated impacting device includes a differential piston slidably disposed in a bore, and having an impacting surface and a piston rod facing at the other end a valve sleeve circumscribing the piston rod, there being an annular space between the rod and the valve, the valve having a first and a second position; a first duct leads from a pressure source to the bore and is governed by the valve for acting or not acting on the larger one of the two piston surfaces respectively in the first and second positions of the valve; a second duct leads from the source to the bore for acting on the smaller one of the piston surfaces; a third duct leads from the bore at a location below the valve to a ring chamber adjacent the valve, the valve having a collar which is movable in the ring chamber, the piston has a portion which depending on the position of the piston permits or prevents communication between the annular space and the third duct to obtain or not obtain pressurization of the ring chamber for s
    Type: Grant
    Filed: January 2, 1985
    Date of Patent: January 13, 1987
    Assignee: Mannesmann AG
    Inventor: Wilhelm Rode