US3344890A - Lifting arrangement - Google Patents

Lifting arrangement Download PDF

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Publication number
US3344890A
US3344890A US591898A US59189866A US3344890A US 3344890 A US3344890 A US 3344890A US 591898 A US591898 A US 591898A US 59189866 A US59189866 A US 59189866A US 3344890 A US3344890 A US 3344890A
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United States
Prior art keywords
column
plunger
motor
pulley means
bottom portion
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Expired - Lifetime
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US591898A
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English (en)
Inventor
Loef Jakob
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Steinbock GmbH
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Steinbock GmbH
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075—Constructional features or details
    • B66F9/08—Masts; Guides; Chains
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075—Constructional features or details
    • B66F9/20—Means for actuating or controlling masts, platforms, or forks
    • B66F9/205—Arrangements for transmitting pneumatic, hydraulic or electric power to movable parts or devices

Definitions

  • the invention is concerned with a lifting arrangement in which hydraulic power is used for telescopically moving the portions of the column between positions of maximum and minimum length, and for moving the load carrier along the column in an upright path.
  • a primary object of the invention is the provision of a pressure-fluid operated lifting arrangement in which tension members connect the hydraulic motor to the several portions of the column and to the load carrier, and in which the combined length of the tension members is as small as possible.
  • the tension members such as chains, ropes, or cables are subject to wear, and need to be replaced from time to time. A reduction in the length of the tension members significantly reduces the maintenance cost of the lifting arrangement.
  • Yet another object is the provision of a minimum number of guide pulleys or their equivalents over which the tension members are trained, the rate of wear of the tension members being a direct function of this number.
  • a further object is the provision of a unitary hydraulic motor for moving the several portions of the column relative to each other and for moving the load carrier relative .to the column, the motor being supported directly on the vehicle frame so that the motor does not have to be lifted with a movable column portion or with the load carrier.
  • An additional object is the provision of a lifting arrangement in which the hydraulic motor, if interposed between the operator of the vehicle and the load carrier, is not in the normal field of view of the operator when the column is at its minimum height, and does not significantly interfere with inspection of the load carrier by the operator in other positions of the lifting arrangement. More specifically, the invention aims at providing a hydraulic motor whose cylinder and plunger move vertically relative to each other, and whose overall axial dimension in the retracted position of the plunger is not significantly greater than one half of the minimum length of the column.
  • the invention in one of its aspects resides in a lifting arrangement includ ing an elongated column of telescopically variable height, a bottom portion of the column being fastened to the vehicle frame for support, and the top portion being guided on the bottom portion.
  • a load carrier is arranged for movement along the column, and a single, pressure-fluid operated motor mounted on the support causes relative movement of the column portions and of the load carrier.
  • the motor has a cylinder and a plunger of which one, preferably the cylinder, is attached to the support so that the other one, preferably the plunger, moves upwardly away from the cylinder during the axial expansion of the motor and downward toward the cylinder during the contraction of the motor.
  • the first tension member is trained over a first pulley rotatably mounted on the plunger, and its ends are fastened respectively to the column portions in such a manner that the end portions are at least in part downwardly spaced from the first pulley.
  • the second tension member is trained over a second pulley high on the top portion of the column and a third pulley on the plunger.
  • One of its ends is attached to the load carrier, and the other end is fastened either to the top portion of the column or the plunger in such a manner that the load carrier moves upward when the plunger is retracted into the cylinder and third pulley moves with the plunger.
  • FIG. 1 shows as much of a fork lift truck as is needed for an understanding of the invention, the view being in side-elevation and partly in section;
  • FIGS. 2 and 3 show the apparatus of FIG. 1 in different operating positions in corresponding views
  • FIGS. 4 and 4a jointly show the apparatus of FIG. 1 together with its hydraulic circuit, further portions of the apparatus being broken away to reveal internal structure;
  • FIGS. 5 to 7 illustrate a portion of the hydraulic circuit of FIG. 4a in different respective operating positions
  • FIGS. 8 to 10 show a modified embodiment of the invention in views respectively corresponding to those of FIGS. 1, 3, and 2;
  • FIG. 11 shows a portion of the apparatus of FIG. 8 in front elevation and partly in section
  • FIGS. 12 and 13 show a third embodiment of the invention in views corresponding to those of FIGS. 1 and 3;
  • FIG. 14 shows a portion of the device of FIG. 13 in front elevation.
  • FIGS. 1 to 7 there is shown the telescoping column of a fork lift truck.
  • the cylindrical tubular bottom portion of the column is fixedly attached to the front end of the truck body 51 in the usual manner.
  • the coaxial tubular top portion 2 of the column is guided in the bottom portion 1 for vertical movement.
  • An upright stationary cylinder 3 is fixedly mounted in the bottom portion 1, and a hollow cylindrical plunger 4 is coaxially received in the stationary cylinder 3 for vertical movement inward and outward of the open top of the latter.
  • the plunger 4 is hollow and downwardly open toward the stationary cylinder 3.
  • a piston 6 divides the cavity of the plunger 4 into two compartments.
  • a piston rod 5 extends upwardly through a packing 17 in the otherwise closed top of the plunger 4 and carries a U-shaped bracket 7 which rotatably support a pulley 8.
  • Two similar pulleys 9 are mounted on the topmost portion of the plunger 4 for rotation about a common horizontal axis. Yet another pulley it) is mounted at the upper end of the top column part 2.
  • a chain 11 is trained from a fastener 16 near the upper end of the column portion 2 over the pulley 8 on the piston rod 5 and the pulley 10 to a fastener 15 of the load lifting fork 50.
  • the fork is guided vertically on a frame which is fixedly fastened to the top portion 2 of the column in a manner not shown since it is entirely conventional.
  • a pair of chains 12 are trained over the pulleys 9 respectively from fasteners 13 in the bottom part 1 of the column slightly below the upper end of the stationary cylinder 3 to fasteners 14 at the lower end of the column portion 2.
  • the bottom portion 1 of the column is downwardly closed, and a cover (not shown) is normally provided on the top portion 2 to close the column except for an aperture which accommodates the pulley 10.
  • a flexible pressure hose 26 connected to the nipple 18 is wound on a reel 21 rotatably attached to the bottom portion 1 of the column.
  • the reel is equipped with a non-illustrated spring which tends to turn the reel 21 counterclockwise, as viewed in FIG. 4, and thereby wind the hose 29 on the reel.
  • the nipple 18 travels in non-illustrated vertical slots of the column portions 1, 2 when the apparatus moves between the positions illustrated in FIGS. 1, 2, and 3.
  • the hose 20 is connected to a hollow trunnion of the reel 21 in a conventional manner.
  • Pipes 22, 23 lead from the trunnion on the reel 21 and from the nipple 19 to a rotary control valve 28 which is operated by means of a radial arm 25.
  • the rotary member 24 of the valve 28 has two circumferentially spaced recesses 26, 27 in its otherwise cylindrical face.
  • the recesses may be aligned with openings in the valve housing which communicate respectively with the pipes 22, 23, with extensions 29, 30 of the pipes 23, 22, with a return line 31, and with the discharge pipe 34 of a motor driven pump 33.
  • the return line 31 has an open end in a sump 32 in which the suction pipe of the pump 33 is partly immersed.
  • the afore-described telescopic column is hydraulically operated by means of the Valve 28 in the following manner 1 Let it be assumed that the apparatus is initially in the position shown in FIG. 3 in which the upper column portion 2 is fully retracted into the bottom portion 1, the piston 6 is in its upmost position, the plunger 4 is retracted into the cylinder 3 and the fork 50 rests on the ground. The valve 28 is brought into the position shown in FIG. 7, and the pump 33 is started.
  • Hydraulic fluid is pumped from the sump 32 through the discharge pipe 34, the recess 27, the extension 30, the pipe 22, and the hose 20 into the plunger compartment above the piston 6 while the cylinder 3 and the communication compartment of the plunger 4 under the piston 6 are vented to the sump 32 through the pipe 23, the recess 26 of the valve 28, and the return line 31 which is equipped with a non-illustrated check valve.
  • the piston rod is retracted by the pressure fluid into the plunger 4, and the fork 50 is raised until the position of FIG. 2 is reached.
  • a limit switch in the circuit of the pump motor and a check valve (not shown) in the pipe 34 may be employed in a conventional manner to limit the inward movement of the piston rod 5.
  • the valve 28 is next slowly shifted to the position shown in FIG. 6 in which both pipes 22, 23 are connected to the pump discharge pipe 34 by the extensions 29, 30 and the valve recess 27.
  • the plunger 4 is expelled from the cylinder 3. Because the effective area of the piston 6 is smaller on the annular top face of the piston than on the circular bottom face, the piston rod 5 moves outward of the plunger 4.
  • the rate of fluid flow from the recess 27 to the extension 29 can be throttled by suitably positioning the rotary valve member 24 so that the outward movement of the piston 6 and the piston rod 5 is never faster than the movement of the plunger 4, whereby the fork 50 moves continuously upward until the position of FIGS. 1 or 4 is reached in which the column is extended to its greatest length, and the fork 50 arrives at the highest point to which it can be lifted.
  • valve 28 When the fork 50 is to be lowered, the valve 28 may be shifted to a non-illustrated position intermediate the positions of FIGS. 5 and 6 in which the recess 27 connects the pipe 23 with the return line 31 whereas the pipe 22 and the corresponding extension 30 are blocked. Pressure fluid is thereby released from the cylinder 3 for return to the condition of FIG. 3. It is also possible to shift the valve into the position illustrated in FIG. 5 for lowering the fork 50 whose weight keeps the piston rod 5 in its projecting position.
  • the apparatus may be blocked in the position of FIGS. 1 and 4 by shifting the valve 28 to the position shown in FIG. 4a in which the pipes 22, 23 are connected by the recess 26, and the pump output is directly returned to the sump 32.
  • the fork 5t) and the hydraulic control circuit have been shown in FIG. 4 on the same side of the column 1, 2 for the convenience of pictorial representation. It will be understood that they are actually offset relative to the column axis to prevent interference of the control circuit with the necessary vertical movement of the fork 50.
  • the modified apparatus of the invention shown in FIGS. 8 to 11 has a stationary cylinder 3 in which a hollow plunger 4 is vertically movable.
  • the lower end of the plunger 4 is closed by a bottom plate 36 as is best seen in FIG. 11.
  • a cylindrical plunger rod 5' is coaxially slidable inthe top wall of the plunger 4' so that the end face 6' of the rod 5 may be moved inward of the plunger 4' from the position seen in FIG. 11.
  • a horizontal cross bar 7 on the upper end of the rod 5 carries two freely rotatable pulleys 8.
  • a shaft 37 on the uppermost portion of the plunger 4' carries two coaxial pairs of pulleys 9, 35.
  • the cylinder 3, plunger 4', and rod 5 are arranged coaxially in a tubular column mainly consisting of a bottom portion 1 and a top portion 2 equipped with fasteners 13, 14 and a pulley 10 as described with reference to FIGS. 1 to 7.
  • a load lifting fork 50 is guided on a non-illustrated frame and is suspended by fasteners 15 from two chains 11 trained in sequence over two coaxial pulleys 10 of which only one is visible in the drawing, the pulleys 9 on the plunger 4' and the pulleys 8 on the cross bar 7'.
  • the free ends of the chain 11 are fastened to the shaft 37.
  • Another pair of chains 12 extends between the fasteners 13 and 14, and is trained over the pulleys 35 on the plunger 4'.
  • the cavities within the cylinder 3 and the plunger 4' are connected to a pump and to a sump by means of a control valve arrangement similar to that shown in FIGS. 4a to 7 which permits pressure fluid to be admitted to the cavities and withdrawn to a sump through nipples 18, 19.
  • FIGS. 8 to 11 The apparatus shown in FIGS. 8 to 11 is operated as follows:
  • Pressure fluid is simultaneously released from the cavity of the plunger 4' so that the cross bar 7' and the pulleys 8 mounted thereon move by one half of the stroke of the plunger 4' relative to the top portion 2 of the column from the position indicated by broken lines in FIG. 8 to the fully drawn position in which the fork 50 reaches the highest level above ground.
  • the available displacement of the fork 50 in the apparatus of FIGS. 1 to 7 is twice the combined strokes of the hollow plunger 4 and of the piston 6.
  • the hydraulic apparatus is capable of lifting the fork 50 a distance equal to the sum of twice the stroke of the plunger 4' plus three times the stroke of the rod 5.
  • the difference in available lifting height between the two hydraulic devices is due to the fact that the chain 11 travels over two reversing pulleys in FIGS. 1 to 7 and over three pulleys in FIGS. 8 to 11.
  • the telescoping bottom and top portions 1, 2 of a column are axially moved relative to each other by a hydraulic lifting arrangement which differs from that shown in FIGS. 1 to 7 mainly by the absence of the piston 6 and piston rod 5 and by the provision of a solid plunger 4 having three coaxial pulleys 8', 9, and 9 mounted thereon.
  • a cable 11' whose ends are attached to a fastener 15 on the fork 50 and to a fastener 16' in the axially central part of the column portion 2 is trained over a pulley near the top of the column portion 2 and the pulley 8' on the plunger 4".
  • Two cables 12' are attached to respective fasteners 13 on the column portion 1 and fasteners 14 at the lower end of the column portion 2. The position of the fastener 16 is higher than that of the pulley 8 in all operative positions of the apparatus.
  • the hydraulic control circuit for the apparatus of FIGS. 12 to 14 consists essentially of a non-illustrated three-way valve which permits the cavity of the cylinder 3 to be blocked or to be connected with a pump or with a return line for movement of the apparatus between the positions of FIGS. 12 and 13.
  • the valve may be of the rotary type shown in FIGS. 4a to 7.
  • the hydraulic motor constituted by the cylinder 3 together with the plunger 4 and the piston rod 5, by the cylinder 3 together with the plunger 4 and the rod 5', and by the cylinder 3 together with the plunger 4" has an axial length when in the retracted condition which is not significantly greater than one half of the axial length of the top portion 2 of the column which is equal to the minimum length of the column.
  • the combined length of the tension members emloyed, such as chains and cables, is relatively small, and is particularly small in the embodiment of the invention described with reference to FIGS. 1 to 7.
  • the tension members are subject to unavoidable wear and must be replaced from time to time.
  • the savings achieved by the use of shorter tension members in the first-described embodiment as compared to the embodiment illustrated in FIGS. 12 to 14 more than balance the cost of the more complex structure of the first embodiment during the normal life of the apparatus. Even the apparatus shown in FIGS. 12 to 14, however, is fully effective with cables, ropes, or chains of a much smaller combined length than was possible in similar devices known heretofore.
  • the column of the invention has been shown to consist of cylindrical tubes, it will be understood that the tubes may be replaced by two elongated, telescopically engaged lattice girders as is conventional in this art.
  • Such girders have openings which permit the operator of the fork lift to view the fork and the material to be loaded thereon from a station behind the column.
  • the relatively small height of the several hydraulic motors of the invention even when the fork 50 is at its highest position leaves the operators field of view virtually unobstructed. Only the slim rods 5, 5 may enter the field under the most unfavorable conditions. In the embodiment of the invention shown in FIGS. 8 to 11, the rod 5' moves downward and out of the operators field of view during the lifting operation.
  • the hydraulic motors are free of plungers, piston rods or the like which move outward of a pressure cylinder in a downward direction.
  • the oil leaks due to gravity which are practically unavoidable where a packing extends downward toward the ambient atmosphere are thus safely avoided in the devices of this invention.
  • the hydraulic motors of the invention are readily controlled by a single valve unit as has been shown in FIGS. 4a to 7.
  • the application of analogous valve systems to the second and third embodiments of the invention will be obvious to those skilled in the art.
  • the hydraulic motors have each but a single cylinder member on which all other elements of the motor are arranged.
  • the motors require a minimum of space.
  • the hydraulic motors are subjected to axial stresses only. Forces having radial components cannot be transmitted to the motors by the flexible tension members which connect the motors with the fork 50 and with the movable top portion 2 of the column.
  • the cylinder member is fixedly fastened to the supporting vehicle frame and carries the other element of the hydraulic motor. It transmits the weight of the other elements directly to the vehicle frame 51 which provides its support.
  • the forks 50 of the devices of the invention shown in FIGS. 1 to 11 may be lifted over the full height of the top portion 2 of the column while the latter is retracted.
  • a lifting arrangement for a fork truck and like vehicle comprising, in combination:
  • a pressure-fluid operated motor including a cylinder member having an upright axis and defining a cavity therein, and a plunger member axially movable inward and outward of said cavity, whereby said motor axially contracts and expands during relative axial movement of said members,
  • one of the members of said motor being fixedly mounted on said support, and the other member moving upwardly away from said one member during the expansion of said motor;
  • said end portions being respectively fastened to said bottom portion and to said top portion, and being at least in part downwardly spaced from said pulley means when said column is at said maximum length and at said minimum length thereof;
  • fastening means fastening the other end portion of said second tension member to one of said top portion and said other member for upward movement of said load carrier when said plunger member moves inward of said cylinder member.
  • valve means include means for sequentially admitting said pressure fluid to said one compartment and to said cylinder member.
  • valve means include means for admitting said pressure fluid first to said one compartment and for thereafter admitting said pressure fluid to the cavity of said cylinder member at a throttled rate.
  • said plunger member being formed with another, substantially closed cavity therein, and said rod member being axially movable inward and outward of said cavity
  • valve means connecting said source to said cavities for admitting said fluid to said cavities, and for withdrawing said fluid from the cavities

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  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Structural Engineering (AREA)
  • Civil Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Forklifts And Lifting Vehicles (AREA)
US591898A 1966-05-06 1966-11-03 Lifting arrangement Expired - Lifetime US3344890A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DEST025357 1966-05-06
DEST025551 1966-06-20

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Publication Number Publication Date
US3344890A true US3344890A (en) 1967-10-03

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US591898A Expired - Lifetime US3344890A (en) 1966-05-06 1966-11-03 Lifting arrangement

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US (1) US3344890A (fr)
DE (2) DE1456892C3 (fr)
FR (1) FR1513611A (fr)
GB (1) GB1135814A (fr)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3970171A (en) * 1974-06-26 1976-07-20 Linde Aktiengesellschaft Three-stage load-lifting assembly for fork-lift trucks
US4026432A (en) * 1972-07-06 1977-05-31 Linde Aktiengesellschaft Lift-vehicle assembly
JPS5288169U (fr) * 1975-12-25 1977-07-01
WO1984001765A1 (fr) * 1982-10-25 1984-05-10 Bushnell Sherman W Jr Elevateur
US4552250A (en) * 1983-04-22 1985-11-12 Crown Controls Corporation Lift truck
DE4315823A1 (de) * 1993-05-12 1994-11-17 Jungheinrich Ag Hubgerüst für Flurförderzeuge
EP1136428A2 (fr) * 2000-03-17 2001-09-26 Still Gmbh Dispositif de levage pour un chariot élévateur
EP1357080A2 (fr) * 2002-04-24 2003-10-29 Werner Georg Schröder Chariot élévateur avec mât central
US20060130713A1 (en) * 2004-12-17 2006-06-22 Steelcase Development Corporation Load compensator for height adjustable table
US20100065377A1 (en) * 2008-09-12 2010-03-18 Crown Equipment Corporation Monomast for a materials handling vehicle
US20110225903A1 (en) * 2010-03-22 2011-09-22 Said Lounis Telescopic mast system
US20170275144A1 (en) * 2016-03-24 2017-09-28 Toyota Motor Engineering & Manufacturing North America, Inc. Pneumatic lifting device

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2812102A1 (de) * 1978-03-20 1979-09-27 Jungheinrich Kg Hubgeruest fuer hubgeraete
NL189558C (nl) * 1978-08-14 1993-05-17 Asea Ab Hefinrichting voor vorkhefvoertuigen.
JP2716876B2 (ja) * 1991-04-01 1998-02-18 三菱重工業株式会社 フォークリフトの制御装置
CN103058099B (zh) * 2012-12-28 2017-04-26 上思县东岽电子科技有限责任公司 一种手车式的通用叉车

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2877868A (en) * 1956-05-31 1959-03-17 Multi Lift Co Hydraulic lift for industrial trucks and tractors
US3077951A (en) * 1958-09-22 1963-02-19 Knickerbocker Company Lift truck mast operation sequence mechanism

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2877868A (en) * 1956-05-31 1959-03-17 Multi Lift Co Hydraulic lift for industrial trucks and tractors
US3077951A (en) * 1958-09-22 1963-02-19 Knickerbocker Company Lift truck mast operation sequence mechanism

Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4026432A (en) * 1972-07-06 1977-05-31 Linde Aktiengesellschaft Lift-vehicle assembly
US3970171A (en) * 1974-06-26 1976-07-20 Linde Aktiengesellschaft Three-stage load-lifting assembly for fork-lift trucks
JPS5288169U (fr) * 1975-12-25 1977-07-01
JPS5419027Y2 (fr) * 1975-12-25 1979-07-14
WO1984001765A1 (fr) * 1982-10-25 1984-05-10 Bushnell Sherman W Jr Elevateur
US4458785A (en) * 1982-10-25 1984-07-10 Bushnell Jr Sherman W Lift
US4552250A (en) * 1983-04-22 1985-11-12 Crown Controls Corporation Lift truck
DE4315823A1 (de) * 1993-05-12 1994-11-17 Jungheinrich Ag Hubgerüst für Flurförderzeuge
EP1136428A2 (fr) * 2000-03-17 2001-09-26 Still Gmbh Dispositif de levage pour un chariot élévateur
EP1136428A3 (fr) * 2000-03-17 2004-04-21 Still Gmbh Dispositif de levage pour un chariot élévateur
EP1357080A2 (fr) * 2002-04-24 2003-10-29 Werner Georg Schröder Chariot élévateur avec mât central
EP1357080A3 (fr) * 2002-04-24 2006-05-31 Werner Georg Schröder Chariot élévateur avec mât central
US20060130713A1 (en) * 2004-12-17 2006-06-22 Steelcase Development Corporation Load compensator for height adjustable table
US10420417B1 (en) 2004-12-17 2019-09-24 Steelcase Inc. Load compensator for height adjustable table
US9591920B2 (en) 2004-12-17 2017-03-14 Steelcase Inc. Load compensator for height adjustable table
US10051955B1 (en) 2004-12-17 2018-08-21 Steelcase Inc. Load compensator for height adjustable table
US8091841B2 (en) * 2004-12-17 2012-01-10 Steelcase Inc. Load compensator for height adjustable table
US9913532B1 (en) 2004-12-17 2018-03-13 Steelcase Inc. Load compensator for height adjustable table
US9826825B1 (en) 2004-12-17 2017-11-28 Steelcase Inc. Load compensator for height adjustable table
US20100068023A1 (en) * 2008-09-12 2010-03-18 Crown Equipment Corporation Fork carriage apparatus for a materials handling vehicle
US8851825B2 (en) 2008-09-12 2014-10-07 Crown Equipment Corporation Fork carriage apparatus for a materials handling vehicle
US8714311B2 (en) 2008-09-12 2014-05-06 Crown Equipment Corporation Monomast for a materials handling vehicle
US10144626B2 (en) 2008-09-12 2018-12-04 Crown Equipment Corporation Fork carriage apparatus for a materials handling vehicle
US20100065377A1 (en) * 2008-09-12 2010-03-18 Crown Equipment Corporation Monomast for a materials handling vehicle
US8276326B2 (en) * 2010-03-22 2012-10-02 Serapid Inc. Telescopic mast system
US20110225903A1 (en) * 2010-03-22 2011-09-22 Said Lounis Telescopic mast system
US20170275144A1 (en) * 2016-03-24 2017-09-28 Toyota Motor Engineering & Manufacturing North America, Inc. Pneumatic lifting device
US10160628B2 (en) * 2016-03-24 2018-12-25 Toyota Motor Engineering & Manufacturing North America, Inc. Pneumatic lifting device

Also Published As

Publication number Publication date
DE1456892B2 (de) 1974-10-10
DE1456896C3 (de) 1975-05-28
GB1135814A (en) 1968-12-04
DE1456896B2 (de) 1974-09-26
DE1456892A1 (de) 1969-01-09
DE1456896A1 (de) 1968-12-19
DE1456892C3 (de) 1975-05-28
FR1513611A (fr) 1968-02-16

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