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WO2002042649A1 - Cylindre hydraulique de type amortisseur progressif - Google Patents

Cylindre hydraulique de type amortisseur progressif Download PDF

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Publication number
WO2002042649A1
WO2002042649A1 PCT/KR2001/002027 KR0102027W WO0242649A1 WO 2002042649 A1 WO2002042649 A1 WO 2002042649A1 KR 0102027 W KR0102027 W KR 0102027W WO 0242649 A1 WO0242649 A1 WO 0242649A1
Authority
WO
WIPO (PCT)
Prior art keywords
cushion
backward
piston
hydraulic cylinder
stepless
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/KR2001/002027
Other languages
English (en)
Inventor
Hag-Bong Choi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from KR2020000032812U external-priority patent/KR200221797Y1/ko
Application filed by Individual filed Critical Individual
Priority to AU2002223150A priority Critical patent/AU2002223150A1/en
Publication of WO2002042649A1 publication Critical patent/WO2002042649A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20—Other details, e.g. assembly with regulating devices
    • F15B15/22—Other details, e.g. assembly with regulating devices for accelerating or decelerating the stroke
    • F15B15/222—Other details, e.g. assembly with regulating devices for accelerating or decelerating the stroke having a piston with a piston extension or piston recess which throttles the main fluid outlet as the piston approaches its end position

Definitions

  • the present invention relates to a stepless cushion type hydraulic cylinder, and more particularly, to a stepless cushion type hydraulic cylinder capable of minimizing or preventing impact, which is generated at a cushion start time or a cushion termination time by a hydraulic piston when a hydraulic cylinder is stopped at an ahead stage or an astern stage, through a stepless cushion type, thereby preventing all problems due to impact.
  • a hydraulic cylinder In general, for a short- distance transfer of an article or a transfer requiring great power, a hydraulic cylinder has been widely used as an actuator, which transfers the article connected to a piston rod end by moving a piston through an intermediate piston from a low pressure side to a high pressure side using a pressure difference of right and left sides of the piston.
  • Such hydraulic cylinder used for the transfer of the article includes: a piston for converting hydraulic difference between a forward port and a backward port, through which hydraulic pressure comes in and out, into a transfer power; a piston rod transmitting power to the article; a body supporting the piston and the piston rod and facilitating their operation; and a cover.
  • the hydraulic cylinder further includes a cushion device for relieving impact generated when the article transferred with great power at high speed is stopped suddenly.
  • FIG. 1 illustrates a conventional hydraulic cylinder having the conventional cushion device used for reducing impact generated when the article transferred at high speed is stopped suddenly.
  • the reference numeral 101 designates a tube, 102 a rod, 103 a piston, 104 a rod cover, 105 a head cover, 10 a cushion ring, 107 a cushion control valve, 108 a locker, and 109 a cushion channel.
  • the conventional hydraulic cylinder having the cushion device can provide somewhat of an impact relieving effect by reducing the speed of the piston once(i.e., to 1 stage), which moves at the high speed, at a prescribed position without moving the piston to a termination.
  • a speed difference between the high speed transfer and the 1 stage cushion transfer is wide and the piston is moved at a uniform speed controlled by the cushion valve after the 1 stage cushion, it only divides impact into two and the great impact is still applied to the end part.
  • the cushion valve is controlled to a minimum value (or a lowest speed) to reduce impact of a final stopper, impact applied to the stopper at the time that the piston is stopped is reduced, but the impact value of the 1 stage cushion is increased and it takes much time till the stop time due to the low speed transfer of the piston.
  • Such 1 stage cushion impact moves a machine and the machine is deviated from the right path due to a failure of the level of the machine, and thereby, a poor process or a permanent deformation of the machine may occur.
  • a coupling bolt may be loosed so as to cause various accidents.
  • a second impact applied to the stopper may damage the stopper and the machine may be damaged or cause accidents, and thereby, it may cause a loss of lots of time due to repair.
  • the cushion value is adjusted to the minimum value (or lowest speed) to reduce the impact value at the time that the piston is stopped, the impact value of the 1 stage cushion is increased as much as the reduced value. It increases problems due to the 1 stage cushion and requires more time in carrying out the same work or operation, and thereby, a manufacturing cost is increased.
  • the present invention provides a stepless cushion type hydraulic cylinder, which is applied to a hydraulic or pneumatic actuator using a piston reciprocating by a pressure difference between an inlet side and an outlet side of the hydraulic cylinder, including: forward and backward cushion parts gradually reducing cushion channels of working fluid, which moves toward forward and backward ports by the piston as the piston is inserted into holes concavely fo ⁇ ned in a bottom surface of a rod cover or a head cover.
  • the stepless cushion type hydraulic cylinder according to the present invention adopts the steplessly decelerated cushion part instead of the conventional cushion control valve and the cushion control channel, the cushion control valve and the channel for the control valve are not needed and a manufacturing cost is reduced. Furthermore, because a first deceleration impact value is minimized and a stop impact value of both ends of the cylinder is nearly zero, the hydraulic cylinder can prevent all problems caused by impact at the time of the first deceleration and stop in transferring an article using the hydraulic cylinder, thereby preventing the poor process due to impact, the damage of the stopper and a life reduction of relevant components.
  • FIG. 1 illustrates a vertical sectional view of a conventional hydraulic cylinder
  • FIG. 2 illustrates a vertical sectional view of a hydraulic cylinder according to the present invention
  • FIG. 3 illustrates a vertical sectional view and right and left side views of a slot type detachable cushion part of the hydraulic cylinder according to the present invention
  • FIG. 4 illustrates a partial side view taken along the line of AA' of FIG. 2, showing an operational state of the cushion part of FIG. 3;
  • FIGS. 5 through 16 illustrate a vertical sectional view and right and left side views of cushion parts according to other preferred embodiments of the present invention, wherein FIG. 5 illustrates a taper type detachable cushion part, FIG. 6 illustrates a combined type detachable cushion part, FIG. 7 illustrates a triangle type detachable cushion part, FIGS. 8 and 9 illustrate through hole type detachable cushion parts, FIG. 10 illustrates a slot type integrated cushion part, FIG. 11 illustrates a taper type integrated cushion part, FIG. 12 illustrates a combined type integrated cushion part, FIGS. 13 through 16 illustrate piston detachable type cushion parts;
  • FIG. 17 illustrates a vertical sectional view of the hydraulic cylinder to which a cushion part according to another preferred embodiment of the present invention is applied.
  • FIG. 18 illustrates a vertical sectional view of the hydraulic cylinder to which a cushion part according to a further preferred embodiment of the present invention is applied.
  • a stepless cushion type hydraulic cylinder 1 As shown in FIG. 1, like a conventional hydraulic cylinder widely used in a hydraulic and pneumatic actuator, a stepless cushion type hydraulic cylinder 1 according to the present invention includes a tube 2 forming a body, a rod cover 10 and a head cover 12 inserted into open surfaces of backward and forward sides, a hydraulic piston 3 reciprocating between the covers 10 and 12, and a piston rod 5 connected to the piston 3.
  • the tube 2 is filled with working fluid introduced or discharged through a forward port 20 of the rod cover 10 or introduced or discharged through a backward port 22 of the head cover 12, and the hydraulic working fluid is introduced or discharged by an external hydraulic pump. Furthermore, the piston 3 has forward and backward boss parts 13 and 15 mounted at both sides thereof. Holes 14 and 16, in which cushion parts 7 and 9 formed at the boss parts 13 and 15 of the piston 3 are inserted at a start time or a determination time of the reciprocating motion, are concavely formed in bottom surfaces, i.e., inner surfaces, of the head cover 10 and the rod cover 12.
  • the tube 2 is made of general steel and serves to support the covers 10 and
  • the piston 3 moves along an inner surface of the tube 2 in a working fluid discharging or introducing direction, with power proportioned to a pressure difference between an inlet side and an outlet side of the working fluid and at speed proportioned to a flow rate of the introduced or discharged working fluid.
  • the cushion parts 7 and 9 have a cross- sectional area gradually reduced as becoming more distant form the piston 3. It is preferable that the cushion parts 7 and 9 are made of the same material as the piston 3, the rod cover 10 and the head cover 12. Alternatively, the cushion parts may be made of material having similar thermal expansion coefficient. Additionally, the cushion parts 7 and 9 may be processed by turning, end mill, wire cutting or grinding.
  • the cushion parts 7 and 9 may be formed by detaohably mounting cushion bushes 17 and 19 on the boss parts 13 and 15 of both sides of the piston or by integrating the cushion bushes with outer surfaces of the forward and backward boss parts 13 and 15.
  • the cushion parts 7 and 9 are formed by detachably coupling the cushion bushes 17 and 19 to the boss parts 13 and 15 of the piston 3, and the cushion parts may be divided into 6 types.
  • the cushion parts 7 and 9 shown in FIGS. 2 and 3 have at least one or more of slant slot type cushion channels 11 formed radially on outer surfaces of the cushion bushes 17 and 19.
  • Each slant slot type cushion channel 11 has an inner diameter surface of a tapered rectangular cross-section, which has a radial direction length, i.e., depth, becoming deeper as the channel 11 becomes more distant from the piston 3. Therefore, while the cushion parts 7 and 9 are inserted into the holes 14 and 16 of the forward and backward sides, each slant slot gradually reduces the area of the cushion channel 11 of the rectangular section formed with an inlet edge part of the hole.
  • the cushion bushes 17 and 19 have outer surfaces tapered in the form of a truncated circular cone, of hich a radius is reduced as the cushion bushes become more distant from the piston 3. Also, in this case, when the cushion parts 7 and 9 are inserted into the holes 14 and 16 of the forward and backward sides, the annular cushion channels 11 formed between the outer surfaces of the cushion bushes 17 and 19 and the inner surfaces of the holes 14 and 16 are gradually reduced.
  • the cushion bushes 17 and 19 may have the tapered slant slot type cushion channels 11, which become deeper as becoming more distant from the piston 3.
  • the cushion channels 11 may be ring-type cushion channels 11 formed in such a manner that a plurality of protrusions are formed into the cushion channels 11 when outer end portions of the cushion bushes 17 and 19, which are partly tapered in a beveled form, are inserted into the holes 14 and 16.
  • the cushion parts 7 and 9 shown in FIG. 7 have the cushion bushes 17 and
  • the cushion parts 7 and 9 shown in FIGS. 8 and 9 have at least one or more of cushion channels 11 formed radially by perforating a plurality of through holes 35 in a radial direction to the cushion bushes 17 and 19 mounted on the forward and backward boss parts 13 and 15.
  • the through holes 35 are arranged in uniform width without regard to the distance from the piston 3, and have diameter becoming larger as becoming more distant from the piston 3.
  • the through holes 35 have the same diameter, and are increased in the number and arranged wider as becoming more distant from the piston 3.
  • the through holes 35 of FIGS. 8 and 9 are connected to the holes 14 and 16 by a fluid passing hole 39 formed longitudinally at lower ends of the through holes 35.
  • the cushion parts 7 and 9 according to another preferred embodiment of the present invention, differently from the previous embodiments, have the boss parts 13 and 15 formed in a type of the cushion bushes 17 and 19 shown in FIGS. 3 to 9.
  • the slant slot type cushion channels 11 are directly formed on the outer surfaces of the boss parts 13 and 15.
  • the cushion part 7, 9 are tapered to make the outer surfaces of the boss parts 13, 15 inclined as shown in FIG. 5.
  • the cushion parts 7, 9 are formed by properly combining the cushion parts of FIGS. 10 and 11.
  • the cushion channel shown in FIGS. 7 to 9 may be directly formed on the boss parts 13 and 15.
  • FIGS. 13 to 16 illustrate the hydraulic cylinder 1 of another type.
  • the piston 3 may be formed separately from the piston rod 5. Therefore, without regard to whether the forward cushion part 7 is formed by the detachable cushion bush 17 as shown in FIGS. 13 and 14, or formed on the boss part 13 as shown in FIGS. 15 and 16, the piston 3 and the backward cushion bush 19 are detachably connected on the front and the rear of the outer surface of the backward boss part 15 extending from the forward boss part 13 respectively.
  • the backward cushion part 9 shown in FIGS. 13 and 15 fixes the piston and the backward cushion bush 19 inserted into the outer surface of the backward boss part 15 by a double nut 23 coupled to a screw part 21 extending from the backward boss part 15.
  • the backward cushion part 9 shown in FIGS. 14 and 16 fixes the piston 3 and the backward cushion bush 19 inserted into the outer surface of the backward boss part 15 by a bolt 27 and a washer 28 inserted and coupled into a tap hole 25 formed in the center of the boss part 15.
  • FIG. 17 illustrates a hydraulic cylinder 201 according to a further preferred embodiment of the present invention.
  • the hydraulic cylinder 201 is similar to the hydraulic cylinder 1 in the whole configuration.
  • cushion parts 207 and 209 decelerating the speed of a piston 203 at a start time or a termination time of the reciprocating motion are formed on inner surfaces of forward and backward holes 214 and 216 formed in lower surfaces of a rod cover 210 and a head cover 212.
  • the cushion parts 207 and 209 may have cushion bushes 217 and 219 detachably mounted on the inner surfaces of the holes 214 and 216, or the cushion bushes may be formed integrally with the inner surfaces of the holes 214 and 216 (not shown).
  • the cushion parts 207 and 209 may have at least one or more of tapered slant slot type cushion channels 211 formed radially on the inner surfaces of the cushion bushes 217 and 219 or the inner surfaces of the holes 214 and 216.
  • the cushion channel 211 has a radial direction depth, which becomes shallower toward forward and backward ports 220 and 222.
  • the cushion parts 207 and 209 may have conical cushion channels having a tapered inner surface, which becomes narrower toward the forward and backward ports 220 and 222, like the cushion parts 7 and 9 shown in FIG. 5.
  • the cushion parts 207 and 209 may have combined type cushion channels, in which the tapered slant slot type cushion channels becoming narrower toward the ports 220 and 222 as in the cushion parts 7 and 9 shown in FIG. 6 and the conical cushion channels beveled at inlet edge portion of the inner surface are combined.
  • holes 214 and 216, in which the cushion channels are formed, or forward and backward cushion rings 206 and 208, each of which has an outer diameter equal to each inner diameter of the cushion bushes 217 and 219, are detachably mounted on the outer surfaces of the piston rod 205 and the backward boss part 215, and inserted into the cushion parts 207 and 209. At this time, each cushion ring can be formed integrally with the outer surfaces of the piston rod 205 and the backward boss part 215.
  • FIG. 18 illustrates a hydraulic cylinder 301 according to a still further preferred embodiment of the present invention.
  • the hydraulic cylinder 310 can be applied to the hydraulic cylinders 1 and 201 having all the above types of cushion parts 7, 9, 207 and 209.
  • the hydraulic cylinder 301 includes a tube 302 forming a body, a rod cover 310 and a head cover 312 inserted into forward and backward open surfaces of the tube 302, and a hydraulic piston 303 and a hydraulic piston rod 305 reciprocating the inside of the tube 302.
  • the deeper forward and backward cushion parts 307 and 309 of the piston 303 are inserted into holes 314 and 316, the narrower cushion channels 311 formed at inlet edge portions of holes 314 and 316.
  • Cushion control valves 330 and 331 for controlling buffering power are mounted on the rod cover 310 and the head cover 312, to control a cushion flow rate of working fluid through cushion channels 333 and 335 formed in lower surfaces of the holes 314 and 316 and through cushion channels 337 and 339 connected to the forward and backward ports 320 and 322.
  • cushion bushes 317 and 319 forming the cushion parts 307 and 309 by being coupled detachably or integrally with the outer surfaces of the piston rod 305 and the backward boss part 315 have at least one or more of slant slot type cushion channels 311 formed radially on the outer surface.
  • the cushion channel has an outer diameter surface of a tapered rectangular cross-section in such a manner that the cushion channel, which has a radius smaller than inner diameter of the holes 314 and 316 and maintains a uniform cross-sectional area to a prescribed distance(d) from the piston 303, is deeper in a radial direction as becoming more distant than the prescribed distance(d).
  • a protrusion 329 inserted into the baclcward port 322 is formed at an end surface of the backward boss part 315.
  • a function of the cushion control valves 330 and 331 may be utilized more effectively.
  • various types of cushion parts such as the cushion bushes 317and 319 having beveled type cushion channels 311, each of which has an outer surface tapered in such a manner that the channel has a uniform cross-sectional area to a prescribed distance(d) from the piston 303 and becomes narrower as becoming more distant from the piston 303.
  • the piston 3 is decelerated steplessly in proportion to the tapered angle of the cushion channel or the number(i.e., cross-sectional area) of the slant slots, the moment the cushion parts 7 and 9 are inserted into the holes 14 and 16.
  • the piston 3 introduces or discharges hydraulic working fluid to the forward port 20 or the backward port 22, in the same method as the conventional cylinder, before the cushion parts 7 and 9 are inserted into the holes 14 and 16 formed in the rod cover 10 and the head cover 12.
  • the cushion channel 11 shown in an oblique line in FIG. 4 reduces a flow rate of working fluid toward the backward port 22 because a sectional area of the channel indicated by multiplying width and depth of the channel is gradually reduced from the left to the right.
  • the piston 3 discharges working fluid through the cushion channel 11 having the cross-sectional area reduced from the time that the cushion parts 7 and 9 are inserted into the holes 14 and 16, the piston 3 is gradually decelerated in proportion to a shape and the cross-sectional area of the cushion channel 11 and stopped when touching the external stopper, the rod cover 10 or the head cover 12.
  • the cushion parts 7 and 9 not only the cushion parts 7 and 9 but also the residual cushion channels 11 have a wide area at an initial time that they are inserted into the holes 14 and 16, but the area becomes smaller and finally zero as they are inserted deeper into the holes 14 and 16.
  • the piston 3 discharges hydraulic working fluid in proportion to the area, and moves at speed proportioned to an amount of the discharged hydraulic working fluid. So, also an article connected . to the piston rod is moved at the same speed as the piston 3, and thereby, the speed of the article and impact applied to the article become zero or so when being stopped.
  • the sectional area of the oblique line part has a width of 2mm in consideration of practicality and process efficiency, is deep to the utmost to reduce first deceleration impact, thereby minimizing the first deceleration impact by making the flow rate similar to the time of rapid transfer, i.e., the time before being inserted into the holes 14 and 16.
  • the cushion channel 11 may be formed in various shapes, or the number of the cushion channels 11 may be varied according to size, shape and use purpose of the hydraulic cylinder, like the generally tapered cushion parts 7 and 9 shown in FIG. 5 or the cushion channel 11 of the triangular plane shown in FIG. 7. Furthermore, the cushion bushes 17 and 19 can be removed from the cushion parts 7 and 9 and replaced with other cushion bushes, which are different in the inclined level, number or shape of the cushion channels 11, according to a used condition of the hydraulic cylinder 1.
  • the amount of working fluid introduced into the through holes 35 and discharged to the fluid passing hole 39 becomes smaller as the cushion parts 7 and 9 are inserted deeper into the holes 14 and 16, and thereby a deceleration effect of the piston 3 can be obtained.
  • the cushion parts 207 and 209 are formed on the inner surfaces of the holes 214 and 216, but the deceleration occurs when the cushion rings 206 and 208 of the piston 203 are inserted into the holes 214 and 216. That is, the sectional area of the cushion channel 211 formed by the inlet edge portions of the outer surfaces of the cushion rings 206 and 208 and the inner surfaces of the holes 214 and 216 is gradually reduced while the cushion rings 206 and 208 mounted on the outer surface of the piston rod 205 or the backward boss part 215 are inserted into the holes 214 and 216. Therefore, the amount of the working fluid discharged to the ports 220 and 222 is reduced, and also the piston 205 reduces gradually its speed and stops at the rod cover 210 or the head cover 212.
  • the first embodiment shows the piston mounting type cushion parts 7 and
  • the second embodiment shows the cover mounting type cushion parts 207 and 209.
  • the cushion parts of the first and second embodiments may be combined properly according to a use condition or an operation condition of the hydraulic cylinder by forming the cushion part 7 on the piston rod in the forward side and forming the cushion part 209 on the hole of the head cover in the backward side.
  • the sectional area of the cushion channel 311 is largest at the moment the cushion parts 307 and 309 are inserted into the holes 314 and 316, and is gradually reduced as moving forward or backward, and thereby, the piston 303 is decelerated steplessly during a prescribed period of time in the same way as the first embodiment.
  • the cushion channel 311 maintains the sectional area uniformly to the extent of the prescribed distance (d) right before its sectional area becomes zero.
  • the protrusion 329 is inserted into the backward port 322 at the time that the sectional area becomes uniform, the deceleration action similar to the 1 stage deceleration by the conventional hydraulic cylinder 101 is instantaneously generated within the backward side hole 316, and thereby a double deceleration effect to the piston 303 can be obtained.
  • the buffering power can be controlled immediately and actively according to the use condition by controlling the diameter of the cushion channel 333 using the cushion control valve 331.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Actuator (AREA)

Abstract

La présente invention concerne un cylindre hydraulique de type amortisseur progressif qui peut minimiser ou empêcher les détériorations imputables à des impacts en minimisant ou en empêchant l'impact généré par un piston hydraulique au départ et à la fin du mouvement de va et vient, grâce à un type d'amortisseur progressif. Ce cylindre hydraulique de type amortisseur progressif, qui est appliqué à un actionneur hydraulique ou pneumatique utilisant un piston (3) en va et vient par une différence de pression entre un côté d'orifice d'entrée et un côté d'orifice de sortie du cylindre (1) hydraulique, comprend: des parties (7, 9) amortisseur avant et arrière qui réduisent progressivement les canaux amortisseur (11) de liquide de travail, lequel se déplace vers des orifices (20, 22) avant et arrière par la force du piston (3) lorsque celui-ci est introduit dans des trous (14, 16) concaves formés sur la surface de fond d'un manchon (10) ou d'un capot (12). Cette invention qui adopte des parties (7, 9) d'amortisseur progressif à la place des clapets et des trous de commande d'amortisseur conventionnels, peut réduire un coût de fabrication et minimiser la valeur de l'impact au moment du premier amortissement et du premier arrêt, permettant ainsi de facilement porter un article quelconque à l'aide de ce cylindre hydraulique.
PCT/KR2001/002027 2000-11-23 2001-11-23 Cylindre hydraulique de type amortisseur progressif Ceased WO2002042649A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2002223150A AU2002223150A1 (en) 2000-11-23 2001-11-23 Stepless cushion type hydraulic cylinder

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR2020000032812U KR200221797Y1 (ko) 2000-10-10 2000-11-23 무단 완충식 유압 실린더
KR2000/0032812U 2000-11-23

Publications (1)

Publication Number Publication Date
WO2002042649A1 true WO2002042649A1 (fr) 2002-05-30

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PCT/KR2001/002027 Ceased WO2002042649A1 (fr) 2000-11-23 2001-11-23 Cylindre hydraulique de type amortisseur progressif

Country Status (2)

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AU (1) AU2002223150A1 (fr)
WO (1) WO2002042649A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7395749B2 (en) 2005-05-12 2008-07-08 Michael R Adams Pneumatic cylinder
CN103759002A (zh) * 2013-12-31 2014-04-30 中冶海水淡化投资有限公司 一种带有安全装置的水压缸活塞
WO2016079653A1 (fr) * 2014-11-18 2016-05-26 Camozzi S.P.A. Societa' Unipersonale Cylindre pneumatique comprenant un manchon amortisseur
US20220154740A1 (en) * 2019-02-01 2022-05-19 Cnh Industrial America Llc Improved hydraulic cylinder for a work vehicle
US12221178B2 (en) 2020-05-01 2025-02-11 Caterpillar Sarl Articulated truck steering

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52127566A (en) * 1976-04-19 1977-10-26 Toyo Umpanki Co Ltd Fluid pressure cylinder
JPS53112678U (fr) * 1977-02-15 1978-09-08
JPS5996404U (ja) * 1982-12-20 1984-06-30 伊藤鉄工株式会社 流体圧作動シリンダの速度制御装置
JPS6240305U (fr) * 1985-08-30 1987-03-10
JPS62180103A (ja) * 1986-01-31 1987-08-07 Daido Steel Co Ltd 流体圧シリンダ
JPS63118406U (fr) * 1987-01-26 1988-07-30
JPH0444506U (fr) * 1990-08-15 1992-04-15

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52127566A (en) * 1976-04-19 1977-10-26 Toyo Umpanki Co Ltd Fluid pressure cylinder
JPS53112678U (fr) * 1977-02-15 1978-09-08
JPS5996404U (ja) * 1982-12-20 1984-06-30 伊藤鉄工株式会社 流体圧作動シリンダの速度制御装置
JPS6240305U (fr) * 1985-08-30 1987-03-10
JPS62180103A (ja) * 1986-01-31 1987-08-07 Daido Steel Co Ltd 流体圧シリンダ
JPS63118406U (fr) * 1987-01-26 1988-07-30
JPH0444506U (fr) * 1990-08-15 1992-04-15

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7395749B2 (en) 2005-05-12 2008-07-08 Michael R Adams Pneumatic cylinder
CN103759002A (zh) * 2013-12-31 2014-04-30 中冶海水淡化投资有限公司 一种带有安全装置的水压缸活塞
CN103759002B (zh) * 2013-12-31 2016-07-06 中冶海水淡化投资有限公司 一种带有安全装置的水压缸活塞
WO2016079653A1 (fr) * 2014-11-18 2016-05-26 Camozzi S.P.A. Societa' Unipersonale Cylindre pneumatique comprenant un manchon amortisseur
CN107250569A (zh) * 2014-11-18 2017-10-13 卡莫齐机械工具股份公司 具有阻尼套筒的气压缸
CN107250569B (zh) * 2014-11-18 2019-12-10 卡莫齐自动化股份公司 具有阻尼套筒的气压缸
US20220154740A1 (en) * 2019-02-01 2022-05-19 Cnh Industrial America Llc Improved hydraulic cylinder for a work vehicle
US12221178B2 (en) 2020-05-01 2025-02-11 Caterpillar Sarl Articulated truck steering

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