Working Member Or Part Carried Thereby Uncovers Inlet Port Patents (Class 91/25)
-
Patent number: 10996016Abstract: A hydraulic cylinder with a load distribution nut connected to an end cap reduces fatigue experience by the end cap portion of the cylinder. The load distribution nut separates the axial load generated in the system from a single to multiple load paths. By introducing additional load paths, the load experienced by the traditional load path is reduced. Additionally, the load experienced by the end cap can be tailored by modifying the design of the load distribution nut and end cap. By either increasing or decreasing the surface area of the load distribution nut the axial load reduction on the end cap is correspondingly decreased or increased.Type: GrantFiled: August 22, 2019Date of Patent: May 4, 2021Assignee: U.S. Government as Represented by the Secretary of the ArmyInventors: Adam Jarvis, Joseph Troll, Matthew Jones, Luke Helsel
-
Patent number: 10988358Abstract: An apparatus includes a housing, a piston, an input cavity, a first actuating shaft, a first output cavity, and a second output cavity. The housing comprises an input port, a first output port, a second output port, a first end, a second end, a first wide wall having a first internal surface, and a chamber at least partially defined by the first end and the first internal surface. The piston is able to actuate along the first internal surface of the first side wall. The input cavity is in fluid communication with the input port. The first output cavity is in fluid communication with the first output port. The second output cavity is in fluid communication with the second output port. The first actuating shaft is fixed to the piston and helps fluidly isolate the first output port from the second output port.Type: GrantFiled: September 24, 2018Date of Patent: April 27, 2021Assignee: Vehicle Service Group, LLCInventors: Steven H. Taylor, Brian E. Kelley, Kevin S. Katerberg, Austin Deuerling
-
Patent number: 7624574Abstract: A piston apparatus which configures an air bearing by introducing a compressed working media into an inside of a piston, and ejecting the working media from plural holes arranged on a circumferential portion of the piston into a clearance between the piston and the cylinder, which prevents a back-flow of the working media in the piston to a working space, and which readily secures reliability and longevity is provided.Type: GrantFiled: December 27, 2005Date of Patent: December 1, 2009Assignee: Toyota Jidosha Kabushiki KaishaInventors: Daisaku Sawada, Hiroshi Yaguchi, Shinichi Mitani
-
Patent number: 6293175Abstract: A web cut-off device including a frame defining a piston chamber, a piston movable in the piston chamber, a cutter blade attached to the piston such that upon movement of the piston in a first direction, the cutter blade is adapted to engage and cut a web, at least one pressure chamber and lower connecting ducts for connecting the pressure chamber(s) to a lower part of the piston chamber. The ducts opening directly into opposed side walls defining the piston chamber such that the piston operates as a valve between the piston chamber and the pressure chamber(s).Type: GrantFiled: June 7, 1999Date of Patent: September 25, 2001Assignee: Valmet CorporationInventors: Petri Enwald, Aaron Mannio, Pekka Ruha, Kalevi Vesterinen
-
Patent number: 5778754Abstract: A valve assembly (10) for controlling a pneumatic brake booster comprises a valve housing (16) with a first and a second valve seat (18, 20) as well as with a valve body (26) adapted to be applied to both valve seats (18, 20). In one position of an operating member (24) the valve body (26) is lifted off the first valve seat (18) only, while in another position of the operating member (24) it is lifted off the second valve seat (20). Radially outside the valve housing (16) an annular third valve seat (64) and a control sleeve (60) surrounding the valve housing are arranged, which as an additional valve body can be axially moved by means of the operating member (24) relative to the valve housing (16).Type: GrantFiled: March 26, 1997Date of Patent: July 14, 1998Assignee: Lucas Industries public limited companyInventor: Manfred Kaub
-
Patent number: 5228380Abstract: A linear drive comprising a drive member adapted to be reciprocated axially in a housing between two end positions. Opposite to the former there is a wall on at least one axial side. There are means to reduce the impact in the end position, such means having an annular lip. The lip is arranged on the drive member or on the wall and respectively faces the wall or the housing. The lip defines a damping space which is open on an impact side. If the drive member approaches one end position thereof, the damping space is occluded and reduced in volume so that some trapped fluid will escape via a relief opening so that there is a braked part of the stroke. Using simple means it is therefore possible to provide an extremely efficient fluid damping at the end position.Type: GrantFiled: August 28, 1992Date of Patent: July 20, 1993Assignee: Festo KGInventors: Kurt Stoll, Eugen Schlotzer, Herbert Kongeter
-
Patent number: 4858937Abstract: The sealing apparatus is designed to automatically maintain the pressure of a buffer fluid above that of the sealed fluid. The apparatus consists of a cylinder (1) which has a movable piston (4, 5) therein. The piston (4, 5) is coupled to a valve shaft (8) and a first chamber (Z) in communication with sealed fluid is disposed on one side of the piston and a second chamber (Y) is on the other side of the piston for continuous communication with the buffer fluid. Recharging means in the form of a valve (12) and third chamber (X) which contains buffer fluid is a pressure greater than (Y) are associated with the second chamber (Y) so that in response to failure of seals the buffer fluid pressure drops in chamber (Y) and the pistons (4, 5) rise so that shaft mounted valve (12) is disengaged from valve seat (14) allowing high pressure buffer fluid to be transferred from chamber X to chamber Y.Type: GrantFiled: June 8, 1987Date of Patent: August 22, 1989Inventors: Anthony C. Fairlie-Clarke, Charles O. Etheridge
-
Patent number: 4843951Abstract: A servocylinder (1, 3, 4) with an electric piston end position transmitter is suggested. It is constructed as a piezoelectric converter (17 and 18). By means of applying voltage to the piezoelectric converter (17 and 18) the latter becomes a regulating element which overcomes a force holding the piston (2) in its stroke end position and removes the piston (2) from its position in which the feed line (7 and 8) of the pressure medium is sealed.Type: GrantFiled: October 6, 1987Date of Patent: July 4, 1989Assignee: Robert Bosch GmbHInventors: Gerhard Bruggen, Manfred Gaugler, Dieter Karr, Josef Winkler
-
Patent number: 4823588Abstract: The present invention is a hydraulic hand-tool which includes an elongate piston having at least two sections of different transverse cross-sectional areas, a housing including a hollow front end portion having an interior surface defining a plurality of sections with different inner diameters corresponding in size, position and number to accommodate the sections of the piston in a manner which permits the piston to slide in a reciprocating manner within the hollow forward end of the housing and to define a main chamber and at least one auxiliary chamber for receiving hydraulic fluid as the piston slides in a forward direction; an hydraulic fluid conduit having a primary line with an end opening directly into the main chamber and at least one supplemental line communicating with at least one of the auxiliary chambers after the piston slides in a forward direction a predetermined distance; an hydraulic fluid or reservoir adapted to supply hydraulic fluid to another end of the primary line; and a pump in communType: GrantFiled: November 6, 1987Date of Patent: April 25, 1989Assignee: Societe D'Etudes Et De Methode D'ApplicationsInventors: Marcel Bussereau, Alain Courtois, Jean-Pierre Huet
-
Patent number: 4807514Abstract: 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: GrantFiled: April 4, 1988Date of Patent: February 28, 1989Inventor: Claude A. Gartzmuller
-
Patent number: 4785712Abstract: A hydraulic operating apparatus in which a differential piston is used as a drive unit, and in which the differential piston is driven by applying a high pressure fluid on a large piston face side through a hydraulic pressure control device for controlling the hydraulic pressure, and a high pressure fluid always being applied on the small piston face side. The hydraulic operating apparatus is constructed such that a high pressure fluid is applied concurrently on both piston faces when the differential piston stops at its receded position, and a thrust generated due to the difference between the forces applied on the both piston faces is held in check by a holding device acting on the differential piston or its extension. The differential piston is moved forward upon the removal of the holding force of the holding device, and the piston is moved backward upon the removal of the high pressure fluid on the large piston face side.Type: GrantFiled: May 27, 1986Date of Patent: November 22, 1988Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Toshiaki Yoshizumi, Tsutomu Sugiyama
-
Patent number: 4766802Abstract: Small-sized engine operated by an expanding gaseous fluid, which comprises a cylinder (18), a piston (20) and an inlet valve (38), the upper parts of the cylinder (18) and the piston (20) cooperating momentarily with a perforated (29) resilient membrane (28) circumferentially secured to the cylinder (18) and performing the functions of a pneumatic seal temporarily.Type: GrantFiled: March 27, 1987Date of Patent: August 30, 1988Inventors: Alessandro Caenazzo, Silvana Pasqualotto
-
Patent number: 4730540Abstract: The cylinder for a two cycle engine includes at least a port opened and closed by a piston in the cylinder the port being divided into a plurality of port portions by a rib extending longitudinally of the cylinder. The inner surface of the cylinder is formed with elongated concave recesses at the respective ends of the rib extending in the direction of extension thereof for regulating the pressing force per unit area of honing process. Each of the concave recesses has preferably substantially the same width as the width of the rib and the sum of the lengths of the concave recesses is preferably substantially the same as the length of the port.Type: GrantFiled: June 27, 1986Date of Patent: March 15, 1988Assignee: Kawasaki Jukogyo Kabushiki KaishaInventor: Sosuke Kinouchi
-
Patent number: 4569271Abstract: An hydraulic booster has a housing provided with a bore, an inlet connected to a source of pressure fluid, and an outlet connected to a reservoir for fluid, a boost piston being advanced in the bore in response to pressurization of a boost chamber, the boost chamber being pressurized under the control of a valve mechanism operative in response to a load applied to an input member. Two connections are provided between the source and the boost chamber, both connections being closed when the booster is inoperative, and when the booster is operated the first connection is opened following initial movement of the input member, and the second connection is opened following initial movement of the boost piston in response to pressurization of the boost chamber. Thus the booster is in a closed center mode when inoperative, but operates in an open center mode. The connections are preferably controlled by valves. The input load may be applied in tension or compression.Type: GrantFiled: June 6, 1983Date of Patent: February 11, 1986Assignee: Lucas Industries Public Limited CompanyInventor: Desmond H. J. Reynolds
-
Patent number: 4563938Abstract: A cylinder (15) is reciprocable in the housing (11) of a hydraulic percussive tool and a piston hammer (16) is reciprocable in the cylinder. The force between the cylinder and the housing is constant during the cycle of reciprocation and as a result the housing (11) is practically not vibrating at all. The piston hammer (16) and the cylinder (15) are coupled together to move conjointly during a part of each forward stroke of the hammer piston, which ensures the timing of the reciprocation of the hammer piston 16 and the cylinder (15).Type: GrantFiled: July 23, 1984Date of Patent: January 14, 1986Assignee: Atlas Copco AktiebolagInventor: Stig R. Henriksson
-
Patent number: 4480525Abstract: A control device for working cycles of a self-propelled pneumatic boring device with a non-rotatable axially displaceable impact piston controllable by control edges of a control sleeve supported axially non-displaceably but rotatably and at its front end forming a control head with the control edges. The control head engaging in a cylindrical recess at a rear end of the impact piston cooperates with a radial main control opening formed in the impact piston in the vicinity of the recess. The control edges form two different pairs of the control edges, offset peripherally as well as axially such that respectively in one rotated position of the control sleeve only one of the pairs is aligned for cooperation with the main control opening. The impact piston is formed with at least one additional control opening which cooperates with the other pair and has a flow cross-section considerably smaller than that of the main control opening.Type: GrantFiled: January 27, 1982Date of Patent: November 6, 1984Inventor: Gustav Jenne
-
Patent number: 4467699Abstract: A valveless, pneumatic motor including a cylinder within which a hammer piston reciprocates and a buffer ring fixedly secured within the cylinder. A source of motive fluid under pressure cooperates with the buffer ring which through supply porting provides pressurized motive fluid alternately to opposed faces of the piston head. Intake ports are formed within the piston stem and adapted to cooperate intermittently with the buffer ring supply porting to provide motive fluid to the piston interior wherein an axial bore transmits the fluid along the stem toward the piston head and discharge porting delivers the motive fluid to the forward face of the piston head thereby urging the piston rearwardly. A reduced diameter portion of the piston stem then comes into communication with the buffer ring supply porting and permits the motive fluid to impinge directly on the rearward face of the piston head without passage through the piston to urge the piston forwardly.Type: GrantFiled: November 4, 1981Date of Patent: August 28, 1984Assignee: Joy Manufacturing CompanyInventor: Louis H. LeBlanc
-
Patent number: 4434704Abstract: An apparatus for converting pressure into motion includes a housing having a plurality of ports formed therein. Movably disposed within the housing is a piston having a first plurality of apertures communicating with a first chamber and a second plurality of apertures communicating with a second chamber therein. The piston is positioned within the housing so that the apertures can register with consecutive ones of the ports as the piston is moved in either of two directions within the housing. The movable member is moved by a pressurizing substance applied to a selectable one of the ports through an appropriate valve circuit. The valve circuit is operated by excitation signals from a control member. By operating the valve circuit in an appropriate sequence, the pressurizing substance is sequentially applied to consecutive ones of the ports to move the piston longitudinally through the housing.Type: GrantFiled: April 14, 1980Date of Patent: March 6, 1984Assignee: Halliburton CompanyInventor: Jim B. Surjaatmadja
-
Patent number: 4399968Abstract: An actuator for ejecting a store from an aircraft, with a pre-selected force vs stroke profile, is disclosed. The actuator comprises a cylinder and a fixed tubular member coupled to a source of fluid under pressure having a first array of orifices for flowing fluid into the cylinder. A piston assembly is provided, which is adapted to engage and eject the store. The iston assembly is slidably mounted within the cylinder and telescopically movable over the fixed tubular member from a first position, wherein the piston assembly covers a portion of the first array of orifices, to a second position, wherein the first array of orifices is uncovered. Typically, the pressure level of the source of fluid varies, generally as a function of the flow into the cylinder during the stroke of the piston assembly.Type: GrantFiled: May 16, 1980Date of Patent: August 23, 1983Assignee: Rockwell International CorporationInventors: William H. Stock, Bernard C. Holland, Jr.
-
Patent number: 4362475Abstract: A compressor having an inlet valve which includes a valve housing and a control tube having a portion adapted to be in communication with a source of fluid. A piston is normally spring biased away from a valve element which is adapted to be alternately placed in sealing contact with a valve seat and withdrawn from such contact. The piston and valve element are movably mounted on the exterior of the control tube. Orifices in the control tube are adapted to control movement of the piston against the bias of the spring and also to provide a modulating influence as well as additional pressure balancing characteristics. The valve is also adapted to function as a bypass valve, a check valve and a blowdown function.Type: GrantFiled: March 16, 1981Date of Patent: December 7, 1982Assignee: Joy Manufacturing CompanyInventor: William R. Seitz
-
Patent number: 4359930Abstract: A variable speed multi-cylinder assembly is provided with expandable bushing seals to block leakage of fluid from higher speed stages to lower speed stages.Type: GrantFiled: May 4, 1981Date of Patent: November 23, 1982Assignee: Western Gear CorporationInventors: Robert M. Brown, John H. Short
-
Patent number: 4323002Abstract: A hydraulically actuable piston and cylinder unit comprising a hollow piston rod, slidably housing, at least partially, an elongate extension piece having a circular outer periphery, means to connect mechanically, the extension piece to the piston rod at the outer end of the latter remote from the piston head, at least one fluid passageway communicating between the annulus side of the piston head and the hollow interior of the piston rod, and a fluid seal carried by the extension piece and sealing against the internal periphery of the hollow piston rod, the arrangement being such that the seal always lies between the passageway and the outer end of the hollow piston rod.Type: GrantFiled: May 16, 1980Date of Patent: April 6, 1982Assignee: Fletcher Sutcliffe Wild LimitedInventor: Malcolm Wake
-
Patent number: 4323001Abstract: A bracing jack comprising a cylinder and a jack bar slidable in the cylinder from a bar extended position to a bar retracted position, the jack having an internal locking mechanism including a hydraulic and a mechanical actuator for unlocking under load.Type: GrantFiled: August 21, 1978Date of Patent: April 6, 1982Assignee: Messier-Hispano-BugattiInventors: Jean Masclet, Jacques Veaux
-
Patent number: 4266465Abstract: Fluid-actuated percussion mechanism includes a housing with an internal cylindrical space receiving a reciprocating piston dividing the space into a working stroke chamber and an idle stroke chamber. The mechanism further includes distributing means mounted in the housing and communicating the chambers and the source of the working fluid. The housing also accommodates a work-performing member adapted to receive impacts from the piston. The distribution means includes at the inlet of at least one of the chambers a valve made in the form of a resilient element. The surface of the distribution means has made therein valve seats of which the number corresponds to that of inlets for supplying the working fluid into the chamber.Type: GrantFiled: July 2, 1979Date of Patent: May 12, 1981Inventors: Viktor A. Gaun, Anatoly V. Belousov, Vadim D. Petukhov, Gennady I. Suxov, Nikolai A. Belyaev, Vitaly K. Alyabiev, Klimenty E. Rassomakhin
-
Patent number: 4194435Abstract: The fluid-actuated percussion mechanism includes a housing with an internal ylindrical space wherein a reciprocating piston, which divides the space into a working stroke chamber and an idle stroke chamber, is received. The mechanism further includes fluid distributing means and a distribution unit mounted in the housing for placing the chambers and a source of the working fluid in communication. The housing also accommodates a work-performing member adapted to receive impacts from the piston. The distribution unit includes at the inlet of at least one of the chambers a valve made in the form of a resilient annular element. The surface of the distribution unit has valve seats made in it, the number of which corresponds to that of the inlets for supplying the working fluid into the chambers. The resilient valve element is taut about the surface of the distribution unit in opposition to the inlets and encircles the periphery of the unit.Type: GrantFiled: June 30, 1977Date of Patent: March 25, 1980Assignee: Institut Gornogo Dela Sibirskogo Otdelenia Akademii Nauk SSSRInventors: Viktor A. Gaun, Anatoly V. Belousov, Vadim D. Petukhov, Gennady I. Suxov, Nikolai A. Belyaev, Vitaly K. Alyabiev, Klimenty E. Rassomakhin
-
Patent number: 4173171Abstract: At the beginning of a working stroke of a compressed air loaded working piston disposed reciprocally in a pneumatic operated ramming tool said piston is initially set in motion under the action of minor amounts of compressed air until its top becomes immersed into stored compressed air and the working piston is then exposed to the full force of said stored compressed air to perform its working stroke. This working process permits to use a substantially simpler ramming apparatus.Type: GrantFiled: June 17, 1977Date of Patent: November 6, 1979Assignee: Firma Dieter Haubold Industrielle NagelgerateInventor: Wilfried Lange
-
Patent number: 4154146Abstract: A fluid motor or vacuum break for use with the carburetor of an internal combustion engine in which an output plunger of the motor moves in two stages and at different rates in each of the stages through means of an auxiliary housing supported within the main housing. Upon admission of vacuum pressure to the primary housing and output plunger moves in a first stage at the end of which vacuum pressure is admitted to the auxiliary housing causing it to collapse and move the plunger in a second stage.Type: GrantFiled: September 21, 1977Date of Patent: May 15, 1979Assignee: Schmelzer CorporationInventor: Benjamin C. Benjamin
-
Patent number: 4151784Abstract: A shock absorber of the kind having an infinitely adjustable damping characteristic comprises a main cylinder containing a piston fixed to a piston rod which extends from the main cylinder and liquid within the cylinder acting on the piston. The main cylinder has openings for the flow from it of the liquid upon movement of the piston in the cylinder and an adjustment device is provided for restricting these openings to provide the adjustment of the damping characteristic. The openings are situated in the peripheral wall of the main cylinder and are axially spaced apart from each other in positions in which they are successively passed over and closed by the piston as the piston approaches the end of its stroke at one end of the main cylinder in a damping movement. Thus the flow of liquid from the main cylinder is progressively further throttled by closure of the openings as the piston approaches the end of its movement.Type: GrantFiled: September 13, 1977Date of Patent: May 1, 1979Inventor: Hubert Fussangel
-
Patent number: 4109894Abstract: A pilot valve device adapted to be brought to an open position in response to a mechanical signal so as to cause a compressed fluid to actuate an operating valve. The pilot valve device comprises a main valve located in a pilot valve chamber, and a daughter valve located in a daughter valve chamber formed in the main valve. When a mechanical signal is applied to the daughter valve and brings the same to an open position, a compressed fluid contained in the pilot valve chamber is introduced into a main valve actuating chamber, with the result that the main valve is brought to an open position to permit the compressed fluid to flow into an operating valve actuating chamber.Type: GrantFiled: June 4, 1976Date of Patent: August 29, 1978Assignee: Hitachi, Ltd.Inventors: Haruo Honda, Hiroshi Itoh
-
Patent number: 4103863Abstract: A valve actuator for an expanding gate valve having a gate and a segment thereon. The actuator includes a piston connected to a gate stem and mounted within a cylinder with a pressurized gas on the upper side of the piston and liquid on the lower side of the piston. The gate valve moves from an open position to a closed position across the flow passage at a rapid rate and decelerates adjacent the end of its downward movement upon a metering of the liquid in the cylinder. The expanding gate valve expands laterally into fluid-tight sealing relation at the end of the downward stroke after moving across the flow passage. The bonnet is mounted internally of the valve body and a pressure seal is positioned between the bonnet and the valve body to permit operation of the valve actuator and gate valve even after failure of the pressure seal.Type: GrantFiled: October 4, 1976Date of Patent: August 1, 1978Assignee: ACF Industries, IncorporatedInventors: Robert C. Houlgrave, Larry J. Talafuse
-
Patent number: 4070946Abstract: The actuator piston has a generally cylindrical central projection about the exterior of which a similarly formed rolling diaphragm is closely fitted. The piston rod can turn freely, to avoid any twisting of the piston and diaphragm, and can also be axially withdrawn from its engagement with the piston. Return spring means extends into the diaphragm enclosed part of the piston.Type: GrantFiled: May 3, 1976Date of Patent: January 31, 1978Assignee: Design & Manufacturing CorporationInventors: Roger H. Sandvik, Richard G. Huebscher
-
Patent number: 4056040Abstract: A shock absorber of the kind having an infinitely adjustable damping characteristic comprises a cylinder containing a piston fixed to a piston rod which extends from the cylinder and liquid within the cylinder acting on the piston. The cylinder has openings for the flow from it of the liquid upon movement of the piston in the cylinder and means are provided for restricting these openings to provide the adjustment of the damping characteristic. The openings are situated in the peripheral wall of the cylinder and are axially spaced apart from each other in positions in which they are successively passed over and closed by the piston as the piston approaches the end of its stroke at one end of the cylinder in a damping movement. Thus the flow of liquid from the cylinder is progressively further throttled by closure of the openings as the piston approaches the end of its movement.Type: GrantFiled: April 16, 1975Date of Patent: November 1, 1977Inventor: Hubert Fussangel
-
Patent number: 4026192Abstract: A motor driven by a pressurized fluid medium for operating an impact tool in a linear direction adapted for metal stamping and high velocity milling comprising a housing and a piston unit. The latter comprises a drive piston, a piston rod and a tool. In addition, the motor includes a kinetic energy absorbing device comprising a hydraulic fluid chamber and a retard piston which is rigidly connected to said piston unit and arranged to reciprocate in said fluid chamber. The retard piston retards the piston unit at the end of the strokes only and is freely passed by hydraulic fluid during the working stroke. Cup-shaped means are provided to restrict said by-pass flow of hydraulic fluid at the end of the strokes and thereby protect the motor from excessive stresses during no-load conditions.Type: GrantFiled: May 17, 1974Date of Patent: May 31, 1977Assignee: Atlas Copco AktiebolagInventors: Carl Anders Noren, Bertil Waldemar Sundin
-
Patent number: 4009639Abstract: A hydraulic swing motor which is provided so as to assure an improved cushioning effect near the end of its stroke and ultimately to make possible a reduction in the cushion stroke sector or an increase in the effective stroke, with fluid inlet and outlet passages at the casing being connected to chambers partitioned with a first vane fixed to the shaft side and a second vane fixed to the casing side and which are closed by means of the said first vane when the relative motion of the first and the second vanes nears its end, and with throttle valves to control the fluid discharge rate and relief valves to release the discharge fluid when its pressure rises beyond a certain limit in a section which remains open throughout the whole stroke.Type: GrantFiled: November 28, 1975Date of Patent: March 1, 1977Assignee: Kayabakogyo-Kabushiki-KaishaInventor: Toshihiko Sabashi
-
Patent number: 3973468Abstract: An extendible and contractible shaft comprises a number of shaft members on a common longitudinal axis, each except the outermost member being telescoped within the one next adjacent. Each telescoped member has a piston slidably sealed to the inner wall of the next adjacent outer member to form a series of tandem arranged sealed pistons. Fluid passageways are provided between adjacent shaft members so that fluid supplied under pressure to an inlet port of the device flows through the passageways to all the piston heads, thereby extending the telescoped shaft members and at the same time driving fluid out from under each piston through fluid passageways to an exit port of the device. When the pressurized fluid flow is reversed to send pressurized fluid to the undersides of the pistons, thereby driving fluid above the piston heads out through the first mentioned port, there would normally be incurred substantial shock as each piston head strikes its stop in the retraction operation.Type: GrantFiled: August 2, 1974Date of Patent: August 10, 1976Inventor: Wayne B. Russell, Jr.