US3672159A - Apparatus for crane jibs adapted to be extended and retracted telescopically - Google Patents

Apparatus for crane jibs adapted to be extended and retracted telescopically Download PDF

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Publication number
US3672159A
US3672159A US13991A US3672159DA US3672159A US 3672159 A US3672159 A US 3672159A US 13991 A US13991 A US 13991A US 3672159D A US3672159D A US 3672159DA US 3672159 A US3672159 A US 3672159A
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US
United States
Prior art keywords
jib
valve
pressure
cylinder
chamber
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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.)
Expired - Lifetime
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US13991A
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English (en)
Inventor
Anders Erik Sundin
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A E SUNDIN PRODUKTER AB
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A E SUNDIN PRODUKTER AB
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C23/00—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes
    • B66C23/62—Constructional features or details
    • B66C23/64—Jibs
    • B66C23/70—Jibs constructed of sections adapted to be assembled to form jibs or various lengths
    • B66C23/701—Jibs constructed of sections adapted to be assembled to form jibs or various lengths telescopic
    • B66C23/705—Jibs constructed of sections adapted to be assembled to form jibs or various lengths telescopic telescoped by hydraulic jacks
    • 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
    • F15B15/08—Characterised by the construction of the motor unit
    • F15B15/14—Characterised by the construction of the motor unit of the straight-cylinder type
    • F15B15/16—Characterised by the construction of the motor unit of the straight-cylinder type of the telescopic type

Definitions

  • valve means and control means for applying fluid [56] keferencescned tpressure through the valve means to the hvdraulic cylinders or telescoplng said sect1ons substantially s1multaneously for UNITED STATES PATENTS extension and retraction of the jib.
  • a crane jib which is telescopically extensible and comprises a double-acting hydraulic cylinder, but the latter only operates directly one of the telescopic sections at a time.
  • the retracting and extending movement of the other telescopic sections is brought about by means of a very complicated rope system with running wheels arranged at the outside of the crane jib.
  • the tractive force when extending or shortening the jib by means only a short working life, since it is easily damaged.
  • each individual telescopic section with a hydraulic unit, these hydraulic units being connected in parallel with one another and connected to an actuating device.
  • parallel arrangement of the hydraulic units involves the disadvantage that both the magnitude of the force and the rate of movement of the hydraulic cylinders are different in the two directions of movement. Accordingly, the telescopic sections are not extended simultaneously, and instead the section which has the least frictional resistance is extended first. Since the sequence in which the telescopic sections are extended is not correctly predetermined, the guiding of the hose for the hydraulic fluid within the crane jib is made substantially more difficult. If for example the foremost jib section is extended first, the hydraulic fluid hoses must be capable of being extended in order not to be fractured at the rear edge of the central section.
  • an apparatus which is characterized in that the two hydraulic cylinders are secured to an end wall and situated within the central telescopic section, the piston rod of the one (first) hydraulic cylinder being secured to the end of the inner telescopic section pivotably arranged on the crane column and the piston rod of the second hydraulic cylinder being secured to the end wall of the outer telescopic section, and in that the hydraulic cylinders are connected in series in a pressure fluid system.
  • the apparatus according to the invention is also characterized by elements which, for extension of the crane jib, conduct a pressure fluid from a pressure source by way of a first pressure fluid supply conduit directly into the inner pressure chamber i.e. the pressure chamber situated at that end of the second hydraulic cylinder which is nearest to the crane column, the piston and the piston rod of this hydraulic cylinder being displaced outwardly and pressure fluid present in the outer pressure chamber of this second pressure cylinder being pressed out through an outer communicating conduit and supplied to the outer pressure chamber of the first hydraulic cylinder, whereby this cylinder is displaced relatively to its piston and by means of the said piston pressure fluid present in the inner chamber of the first hydraulic cylinder is pressed by way of an inner communicating conduit, through a valve arrangement and a pressure fluid duct and then introduced into the inner pressure chamber of the second hydraulic cylinder.
  • the apparatus according to the invention is also characterized by elements which in order to shorten the crane jib, introduce a pressure fluid from a pressure source by way of a second pressure fluid supply conduit, through the valve arrangement and the forward communicating conduit and into the inner pressure chamber of the first hydraulic cylinder that is displaced inwards relatively to its piston and pressing pressure fluid through the outer communicating conduit into the outer pressure chamber of the second hydraulic cylinder, whereby the piston of this hydraulic cylinder is displaced inwards relatively to its cylinder, and pressure fluid present in the inner pressure chamber is pressed through the first pressure fluid supply conduit, serving as an inlet when the jib is extended, and supplying it to a pressure fluid container of the pressure source.
  • An apparatus makes it possible to effect a substantially simultaneous extension and also a substantially simultaneous retraction of the individual telescopic sections, and furthermore e.g. the outer most telescopic section can be given, by special choice of dimensions, a greater travel length and a higher speed of displacement than the telescopic section adjacent it.
  • the pressure produced by the lifted load and acting on the bearing parts of the hydraulic section is uniformly distributed, so that at the extension or retraction of the jib the bearing pressure is kept as low as possible in every section.
  • the outermost telescopic section is given a greater travel length, the telescopic sections situated nearer the crane column are given larger bearing surfaces, so that a still more uniform distribution of the bearing pressure in the sections is achieved.
  • FIG. 1 is a side view, partly in section, of a crane jib according to the invention with the telescopic sections fully extended,
  • FIG. 2 shows a longitudinal sectional view through the crane jib in the retracted state
  • FIG. 3 shows the hydraulic system during the extension of the jib, in a diagrammatic view
  • FIG. 4 is again a diagrammatic view, showing the hydraulic system during the retraction of the crane jib and
  • FIG. 5 shows a partial elevational view of a further form of embodiment, illustrating the bearing or mounting of the pressure cylinders on one of the telescopic sections.
  • the crane jib l is mounted to be pivotable on a crane column 2 which is arranged to be rotatable for example on the back of a lorry for pivoting the crane jib 1 in the horizontal plane.
  • the crane jib l is adapted to be lifted and lowered by means of a hydraulic cylinder 3 and consists of three telescopic sections 4,5,6 which are conveniently of rectangular crosssection and of which the inner telescopic section 4, mounted pivotably on the crane column 2, is not mobile in the longitudinal direction of the crane jib l.
  • the two telescopic sections and 6 are arranged to be displaceable whithin one another and to be capable of being contracted into extended from the telescopic section 4.
  • the outer telescopic section 6 is provided at its end wall 21 with a load hook 17 on which the load to be lifted is suspended either directly or by means of a rope, to be then loaded for example on to a motor lorry.
  • the inner and central telescopic sections 4 and 5 are provided within their outer end respectively both above and below with shoulders 43, 43', 44, 44' which serve together with shoulders 45, 45', 46, 46' (see FIG.2) arranged on the inner end of the central and outer telescopic sections 5, 6 above and below and extending radially outwardly, as supporting surfaces, guide shoulders and end stops.
  • FIG. 2 of the drawings also shows that the two hydraulic cylinders 7, 8 are arranged with their end nearest to the crane column 2 at the end wall 13 of the central telescopic section 5.
  • the hydraulic cylinder 7 (in future referred to as the first hydraulic cylinder) is provided with a piston 14 and a piston rod 15 which extends through the end wall 13 of the central telescopic section 5 and at its inner end, nearest the crane column 2, is secured to the end 16 of the inner telescopic section 4 ar ranged pivotably on the crane column 2.
  • the securing element 18'for the hydraulic cylinder 7,- serving as a support, must, owing to the unavoidable deflection of the telescopic sections 5,6 when the crane jib is subjected to considerable load, be made to be somewhat yieldable in a plane transversely to the direction of displacement of the crane jib 1.
  • the second hydraulic cylinder 8 is provided with a piston 19 and a piston rod 20 whose outer end is secured to the end wall 21 of the outer telescopic section 6.
  • the inner end, nearest to the crane column 2, of the hydraulic cylinder 8 (designated hereinafter as the second hydraulic cylinder") is also mounted in the end wall 13 of the central telescopic section 5, as shown in FIG. 2.
  • the hydraulic system comprises the aforesaid pressure fluid container 10, from which the pressure fluid is conveyed by means of the hydraulic pump 9 to the change-over device 11, which changeover device is adjustable to three different positions, namely one position for extension of the crane jib 1, one position for retraction of the said jib, and an intermediate position wherein the pressure fluid is returned directly to the pressure fluid container 10 without influencing the two hydraulic cylinders 7,8.
  • two pressure fluid supply conduits 22, 23 lead to the crane jib 1, the first of which 22 is connected directly to the second hydraulic cylinder 8 and the second 23 to a double-acting non-retum valve 24, which valve is arranged in an inner end portion 25 of the second hydraulic cylinder 8 which is nearest the crane jib 2.
  • This double-acting non-return valve is formed by a valve ball 27 which is mobile in a valve chamber 26 and which blocks the second pressure fluid supply conduit 23 and a pressure fluid duct 28 situated between the valve chamber 26 and the first pressure fluid supply conduit 22.
  • valve chamber 26 Leading to the valve chamber 26 is a further pressure fluid conduit which is referred to hereinafter as the inner communicating conduit 29, which is constantly open and connects the valve chamber 26 to the inner pressure chamber 30, nearest to the crane column 2, of the first hydraulic cylinder 7.
  • the two outer pressure chambers 31, 32, nearest to the load hook 17 (see FIG. 2), of the hydraulic cylinders 7,8 are connected by a pressure fluid conduit, in future referred to as the outer communicating conduit 33, to one another.
  • the piston 14 of the first hydraulic cylinder 7 is also provided with a throughflow duct 34 in the outer end of which there is arranged a spring-loaded valve 35 with a projection 36 which, when the piston 14 has reached its outer end position, abuts against the end wall 37 of the hydraulic cylinder 7 and holds the valve 35 open.
  • the valve 35 is closed by the action of the pressure spring 38 associated therewith.
  • FIG. 5 shows a partial view, shown in longitudinal section, of the mounting or securing of the hydraulic cylinders according to a further form of embodiment, which has a few constructional advantages relatively to the form of embodiment described hereinbefore.
  • the inner end portion 18, 25, nearest to the crane column 2, of the two hydraulic cylinders 7, 8 is constructed as a single end portion 39 and provided with a common mounting portion 40 which is arranged in the end wall 13 of the central telescopic section 5 and is mobile in a plane transversely to the longitudinal direction of the crane jib 1.
  • the pressure fluid duct 28 opens directly into the inner pressure chamber 41 of the hydraulic cylinder 8 and the non-return valve 24 with the connections is so arranged that the valve ball 27 carries out a horizontal movement.
  • pressure fluid is pressed into the inner pressure chamber 30 of the first hydraulic cylinder 7, through the inner communicating conduit 29 and introduced into the valve chamber 26 of the non-return valve 24, the valve ball 27 blocking the second pressure fluid supply conduit 23, which is thus completely inoperative.
  • the pressure fluid is therefore conducted through the pressure fluid duct 28 and into the inner pressure chamber 41 of the second hydraulic cylinder 8 again.
  • Pressure fluid is introduced through the outer communicating conduit 33 into the outer pressure chamber 32 of the second hydraulic cylinder 8, whereby the piston 19 with the piston rod 20 associated therewith and with it also the outer telescopic section 6 are shifted inwards i.e. retracted.
  • the pressure fluid present in the inner pressure chamber 41 of this hydraulic cylinder 8 is conveyed through the first pressure fluid supply conduit 22, which is connected by the change-over device 11 to the pressure fluid container 10, back into the pressure fluid container which itself communicates with the hydraulic pump 9.
  • the valve 35 is opened, the pressure fluid being pressed through the throughflow duct 34 and flowing into the second hydraulic cylinder 8 until the piston 19 thereof has reached its inner end position.
  • the travel length of the hydraulic cylinders 7,8 and their effective cross-sectional areas can be so chosen that the piston 14 of the first hydraulic cylinder 7 reaches its end position before the piston 19 of the second hydraulic cylinder 8 has reached its end position i.e. the central telescopic section 5 has already run in before the running-in movement of the outer telescopic section 6 terminates. If the apparatus is so dimensioned that the pistons 14, 19 reachtheir particular end positions simultaneously, relatively small displacements may occur in time owing to leakage at the piston seals. But the valve 35 guarantees that the two pistons 14, 19 actually occupy their relevant end positions. Since the two outer pressure chambers 31, 32 of the hydraulic cylinders 7, 8 form with the outer communicating conduit 39 a closed hydraulic system, the valve 35 is extremely important for the filling of the system with pressure fluid.
  • the apparatus according to the invention provides a crane jib which is very compact in the retracted position in relation to its operating circle, which is very advantageous when used for example in the case of crane lorries, since cranes used in these are usually arranged, during transport, behind the drivers cab transversely to the longitudinal direction of the lorry, and for this reason should be somewhat less than the overall width of the vehicle.
  • the piston of the second hydraulic cylinder can be provided with a throughflow duct and a valve.
  • several apparatus according to the present invention can be connected following one another in a telescopically reu'actable and extensible crane jib, in which case, for shifting for example six telescopic units, a hydraulic cylinder pair according to the present invention is arranged in the second telescopic section and a further pair of hydraulic cylinders within the fifth telescopic section.
  • a crane jib for attachment to a crane column including in combination a jib inner section pivotally attached to said crane column, a jib central section telescopically disposed with respect to said inner section, a jib outer section telescopically disposed with respect to said central section, first, second and third interior walls of said jib inner, central and outer sections respectively, first and second hydraulic cylinders rigidly attached to said second wall, first and second piston rods respectively of said first and second hydraulic cylinders attached respectively to said first and third walls, a first piston head mounted on said first piston rod within said first cylinder, inner and outer first cylinder chambers separated by said first piston head, a second piston head mounted on said second piston rod within said second cylinder, inner and outer second cylinder chambers separated by said second piston head, an outer communicating conduit connecting said outer cylinder chambers, a flow-through duct in said first piston head connecting said inner and outer first cylinder chambers, a valve within said flow-through duct, a double-acting non
  • a crane jib in accordance with claim 1 in which the valve within said flow-through spring loaded member so that at the outer end position of said piston head said inner and outer first cylinder chambers are connected through said flow-through duct.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Engineering & Computer Science (AREA)
  • Jib Cranes (AREA)
US13991A 1969-02-28 1970-02-25 Apparatus for crane jibs adapted to be extended and retracted telescopically Expired - Lifetime US3672159A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE02764/69A SE329245B (es) 1969-02-28 1969-02-28

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US3672159A true US3672159A (en) 1972-06-27

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US (1) US3672159A (es)
JP (1) JPS49585B1 (es)
CA (1) CA922672A (es)
DE (1) DE2007279A1 (es)
ES (1) ES377311A1 (es)
FI (1) FI52322C (es)
FR (1) FR2033422B1 (es)
SE (1) SE329245B (es)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS49104350A (es) * 1973-02-14 1974-10-02
US3990349A (en) * 1974-04-08 1976-11-09 Charbonnages De France Device for effecting translational movement of a machine
US4141281A (en) * 1975-07-09 1979-02-27 Alfred Herbert Limited Pressure fluid operated feed drive system for a movable member
US4255076A (en) * 1976-06-23 1981-03-10 Jonsereds Ab Loading apparatus with extension boom (telescopic boom) and with hydraulic lines carried by the boom
US4589642A (en) * 1983-08-10 1986-05-20 Stierlen-Maquet Ag Operating table
US4928488A (en) * 1987-09-08 1990-05-29 Walter Hunger Hydraulically-operated support device for semitrailers
EP0567218A1 (en) * 1992-04-23 1993-10-27 Japanic Corporation Telescopic arm assembly with two interconnected hydraulic activators for grab bucket excavator
US5324086A (en) * 1991-07-24 1994-06-28 Mordechai Hammer Device capable of positive extension and retraction using a casading force transfer
CN104875030A (zh) * 2015-05-01 2015-09-02 安庆安星电气有限公司 一种摇臂钻床的伸缩式悬臂
CN104874828A (zh) * 2015-05-01 2015-09-02 安庆安星电气有限公司 一种摇臂钻床
DK201600564A1 (en) * 2016-09-26 2017-09-11 Innovatorlab V/Marcus Reinholdt Pedersen Adjustable arm davit apparatus
US20180273352A1 (en) * 2017-03-22 2018-09-27 Wetherell Mfg Co. Sequential piggyback cylinders for extendable boom crane
CN110386540A (zh) * 2019-07-08 2019-10-29 浙江双金机械集团股份有限公司 用于水平轴冲击式破碎机的锤头提升装置

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU8247382A (en) * 1981-04-14 1983-04-21 Coles Cranes Ltd. Telescopic booms for cranes
SE454268B (sv) * 1987-05-21 1988-04-18 Forshaga Mek Verk Ab Anordning vid hydrauliskt styrda forlengningsbommar for kranar

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2646025A (en) * 1951-02-07 1953-07-21 Bendix Aviat Corp By-pass valve for hydraulic motors
US2984373A (en) * 1958-07-16 1961-05-16 Warner Swasey Co Material handling apparatus
US3212604A (en) * 1962-04-09 1965-10-19 Eaton Metal Products Company Extensible derrick
US3240008A (en) * 1963-04-08 1966-03-15 Wayne W Mcmullen Control system for a material handling vehicle
US3250182A (en) * 1963-08-01 1966-05-10 Harold K Nansel Multiple extension apparatus
US3300060A (en) * 1965-02-03 1967-01-24 Pettibone Mulliken Corp Booms with sequential hydraulic extension
US3407947A (en) * 1965-12-22 1968-10-29 Antonio Valla & C S N C Material-moving device for moving objects

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2646025A (en) * 1951-02-07 1953-07-21 Bendix Aviat Corp By-pass valve for hydraulic motors
US2984373A (en) * 1958-07-16 1961-05-16 Warner Swasey Co Material handling apparatus
US3212604A (en) * 1962-04-09 1965-10-19 Eaton Metal Products Company Extensible derrick
US3240008A (en) * 1963-04-08 1966-03-15 Wayne W Mcmullen Control system for a material handling vehicle
US3250182A (en) * 1963-08-01 1966-05-10 Harold K Nansel Multiple extension apparatus
US3300060A (en) * 1965-02-03 1967-01-24 Pettibone Mulliken Corp Booms with sequential hydraulic extension
US3407947A (en) * 1965-12-22 1968-10-29 Antonio Valla & C S N C Material-moving device for moving objects

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS49104350A (es) * 1973-02-14 1974-10-02
JPS5328705B2 (es) * 1973-02-14 1978-08-16
US3990349A (en) * 1974-04-08 1976-11-09 Charbonnages De France Device for effecting translational movement of a machine
US4141281A (en) * 1975-07-09 1979-02-27 Alfred Herbert Limited Pressure fluid operated feed drive system for a movable member
US4255076A (en) * 1976-06-23 1981-03-10 Jonsereds Ab Loading apparatus with extension boom (telescopic boom) and with hydraulic lines carried by the boom
US4589642A (en) * 1983-08-10 1986-05-20 Stierlen-Maquet Ag Operating table
US4928488A (en) * 1987-09-08 1990-05-29 Walter Hunger Hydraulically-operated support device for semitrailers
US5324086A (en) * 1991-07-24 1994-06-28 Mordechai Hammer Device capable of positive extension and retraction using a casading force transfer
EP0567218A1 (en) * 1992-04-23 1993-10-27 Japanic Corporation Telescopic arm assembly with two interconnected hydraulic activators for grab bucket excavator
AU669885B2 (en) * 1992-04-23 1996-06-27 Nikken Corporation Deep excavator
CN104875030A (zh) * 2015-05-01 2015-09-02 安庆安星电气有限公司 一种摇臂钻床的伸缩式悬臂
CN104874828A (zh) * 2015-05-01 2015-09-02 安庆安星电气有限公司 一种摇臂钻床
DK201600564A1 (en) * 2016-09-26 2017-09-11 Innovatorlab V/Marcus Reinholdt Pedersen Adjustable arm davit apparatus
DK179039B1 (en) * 2016-09-26 2017-09-11 Innovatorlab V/Marcus Reinholdt Pedersen Adjustable arm davit apparatus
US20180273352A1 (en) * 2017-03-22 2018-09-27 Wetherell Mfg Co. Sequential piggyback cylinders for extendable boom crane
CN110386540A (zh) * 2019-07-08 2019-10-29 浙江双金机械集团股份有限公司 用于水平轴冲击式破碎机的锤头提升装置

Also Published As

Publication number Publication date
JPS49585B1 (es) 1974-01-08
FI52322B (es) 1977-05-02
ES377311A1 (es) 1972-06-16
FR2033422A1 (es) 1970-12-04
SE329245B (es) 1970-10-05
FR2033422B1 (es) 1975-01-10
DE2007279A1 (de) 1970-09-17
FI52322C (fi) 1977-08-10
CA922672A (en) 1973-03-13

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