EP0835220B1 - Fleche extensible particulierement destinee a des grues - Google Patents
Fleche extensible particulierement destinee a des grues Download PDFInfo
- Publication number
- EP0835220B1 EP0835220B1 EP96915286A EP96915286A EP0835220B1 EP 0835220 B1 EP0835220 B1 EP 0835220B1 EP 96915286 A EP96915286 A EP 96915286A EP 96915286 A EP96915286 A EP 96915286A EP 0835220 B1 EP0835220 B1 EP 0835220B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- piston
- piston rod
- cylinder
- transmission element
- chamber
- 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.)
- Expired - Lifetime
Links
- 230000005540 biological transmission Effects 0.000 claims abstract description 17
- 230000033001 locomotion Effects 0.000 claims description 7
- 238000006073 displacement reaction Methods 0.000 claims description 6
- 239000004519 grease Substances 0.000 claims description 5
- 230000002779 inactivation Effects 0.000 claims 1
- 238000010276 construction Methods 0.000 description 4
- 239000000969 carrier Substances 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 210000002445 nipple Anatomy 0.000 description 1
Images
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
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
- F15B11/20—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors controlling several interacting or sequentially-operating members
- F15B11/205—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors controlling several interacting or sequentially-operating members the position of the actuator controlling the fluid flow to the subsequent actuator
-
- 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
Definitions
- the present invention relates to an extendible boom comprising a plurality of telescopical boom sections which are displaceable into and out of each other by means of double-acting hydraulic units, of which each one separately comprises a cylinder and a hollow piston rod with a piston that divides the interior of the cylinder into two chambers, namely a piston side chamber between the piston and a first gable portion of the cylinder and a piston rod chamber between the piston and a second gable portion with a hole through which the piston rod is reciprocally displaceable, two main conduits being arranged between co-operating, adjacent hydraulic units, of which conduits a first one has the purpose of feeding oil or a hydraulic medium from an inner hydraulic unit to the piston side chamber in the outwardly next unit in order to push the piston rod out of the cylinder of the latter unit, while the other conduit has the purpose of feeding oil to the piston rod chamber in the same cylinder from the inwardly located unit in order to push the piston rod into it.
- Extendible booms of the type generally defined above are often included as jib levers in cranes.
- a primary object of the invention is to create a boom whose hydraulic units for a sequential adjustment of the different telescopic boom sections are of such a nature that they are capable of reliably holding their piston rod in the pushed-out end position as long as the piston rod in each outwardly located hydraulic unit is not pushed into its inner end position.
- a further object is to achieve this sequential adjustment automatically and in a mechanical way, i.e., without necessitating for instance an electric regulation of valves.
- a further object of the invention is to realize the problem solution by means of hydraulic units which are hydraulically connected to each other via stationary or stiff conduits.
- reference numeral 1 generally designates a hydraulic unit or a so called hydraulic cylinder which comprises a cylinder 2 as such, a piston 3 and a piston rod 4.
- the piston 3 divides the interior of cylinder 2 into two chambers, namely a piston side chamber 5 between the piston and a first gable portion or bottom 6, and a piston rod chamber 7 between the piston and a second gable portion 8 in which there is a hole 9 through which the piston rod 4 is reciprocally movable.
- a first main conduit 10 is connected to the piston rod chamber 7.
- the piston rod 4 is hollow by comprising a tubular portion 12 that confines a cavity 13.
- piston rod 4 At its free end, piston rod 4 has a head 14. In the area of this head, two further hydraulic conduits designated 10' and 11', respectively, are connected to the piston rod.
- FIG 2 illustrates how an extendible boom according to the invention comprises several further hydraulic units 1', 1" and 1''' beside the unit 1.
- the individual telescopic boom sections that together form an extendible boom, are not shown in the drawings, in practice the first hydraulic unit 1 is mounted on an inner boom section, the head 14 on the piston rod of the unit being connected to the second innermost boom section on which in turn the hydraulic unit 1' is mounted.
- the hydraulic unit 1' has the head 14' of the piston rod connected with the next telescopic boom section, and so forth. All the hydraulic units with the exception of the outer unit 1"' are of the design shown in figure 1.
- the outer hydraulic unit 1"' is of a simpler construction and comprises beside a cylinder merely a simple piston and a simple piston rod.
- the conduits 10', 11' hydraulically connect the unit 1 with the unit 1'.
- the conduits 10", 11" connect the unit 1' with the unit 1", and so forth.
- carriers designated 15 are connected to the free ends of the piston rods to all hydraulic units except the unit 1.
- a transmission element 16 is arranged within the hollow piston rod 4, which element co-operates in the region of its inner end with a locking device designated by reference numeral 17 in its entirety, and which at its opposite end may at least indirectly be activated by a carrier 15 of an adjacent hydraulic unit.
- the transmission element 16 has the shape of a tube whose interior forms a duct or intermediate conduit 18.
- the locking device 17 comprises one or several radially movable taps arranged to, when in an active locking state, engage into a seat 19, which in the example is illustrated in the form of a circumscribing groove on the inside of a ring-shaped flange 20 that protrudes from the inside of the gable portion 8.
- the tube 16 has a wedge body 21 that has an oblique or conical surface arranged to cooperate with a correspondingly oblique surface on the locking tap or taps, more specifically in such a way that each locking tap is radially displaced outwardly when the wedge body 21 is distanced from the piston 3.
- the wedge body 21 is accommodated in a chamber 22 inside the piston portion.
- the chamber 22 is sealed relative to the cavity 13 in the piston rod 4 by a gasket 23.
- the chamber 22 communicates with the piston rod chamber 7 via a constantly open transverse hole 24. Further, chamber 22 communicates with the duct 18 within tube 16 via a second transverse hole 25 in the wall of the tube.
- the piston 3 further comprises a non-return or clack valve which is schematically exemplified in the form of a sphere 27 that is loaded by a spring force, as illustrated in the form of a pressing coil spring 27'.
- a non-return or clack valve which is schematically exemplified in the form of a sphere 27 that is loaded by a spring force, as illustrated in the form of a pressing coil spring 27'.
- the ball 27 is shown in a closing state in which it impedes communication between the piston side chamber 5 and a duct 28 extending through the piston, which duct leads to the cavity 13 of the piston rod.
- the clack valve may be opened against the force of spring 27', permitting communication between chamber 5 and duct 28. This happens when the piston arrives to its outer end position and the free end of tap 29 gets in contact with the annular flange 20.
- conduit 10' is connected to and communicates with cavity 13 in the piston rod 4.
- the tube 16 has on one hand a transverse hole 30 in the tube wall, and on the other hand a first auxiliary piston 31.
- the transverse hole 30 is located in a chamber 32 which on one hand is sealed relative to the cavity 13 by a gasket 33, and on the other hand by a second gasket 34 relative to a space 35 in which the first auxiliary piston 31 is reciprocally movable.
- the auxiliary piston 31 divides the space 35 into two part-chambers 36, 37.
- Auxiliary piston 31 is actuated by a spring force that is schematically illustrated in the form of a pressing coil spring 38, which constantly strives to move the auxiliary piston in a direction outwards, towards the free end of the piston rod.
- Part-chamber 37 is also delimited by a second auxiliary piston 39 which is reciprocally movable in a course 40 in the piston rod head 14.
- Part-chamber 37 is filled with a hydraulic medium, preferably in the form of a grease that may be filled up via a nipple 41.
- a pressure is upheld in the grease mass, which guarantees that the auxiliary piston 31 and the tube 16 are kept in an inner end position against the force of the spring 38. In this state, the locking device 17 is inactive.
- reference numeral 42 designates a hole in which suitable means may be placed, for instance bolts, for mechanical fastening of the free end of the piston rod to an adjacent telescopic boom section or its hydraulic unit.
- the directional valve connects the conduit 10 with the pump, while the conduit 11 is kept open relative to the tank. Oil is fed into the piston side chamber 5 and sets the piston 3 into motion towards the outer end position. Thereby, any oil in the piston rod chamber 7 is evacuated to the tank via the conduit 11.
- the displacement of the piston the whole way from the inner end position to the outer end position is secured by means of the clack valve 27, which during the displacement prevents any communication between the piston side chamber and the duct 28.
- the oil in the piston rod chamber 7 is forcibly pressed out into the conduit 11 in spite of the fact that the communication with the conduit 11' is open via the transverse hole 24, the chamber 22, the transverse hole 25, the tube conduit 18, the transverse hole 30 and the chamber 32, because of the fact that the piston rod chambers in all the other hydraulic units 1', 1" and 1"' are filled with oil.
- the locking device 17 is located opposite to the seat 19.
- the carrier tap 29 opens the clack valve 27; something that allows communication between the piston side chamber 5 and the duct 28.
- oil may be fed from the chamber 5 into the ring-shaped cavity 13 inside the piston rod and further through the conduit 10' into the piston side chamber in the adjacent hydraulic unit 1'.
- a displacement is initiated of the piston 3' of the latter unit in the direction towards its outer end position, resulting in the piston rod 4' being pushed out of the associated cylinder 2'.
- the carrier 15 is distanced from the free end or head 14 of the first piston rod 4 and liberates the auxiliary piston 39 so that it may move outwardly, out of the appurtenant course.
- the pressure in part-chamber 37 is reduced so that the spring 38 forces the auxiliary piston 31 and the tube 16 to move towards an outer end position.
- wedge body 21 actuates the locking device 17 so that the locking taps of said device engage with the seat 19.
- the device 17 locks the piston 3 mechanically in its outer end position.
- the oil from the conduit 11 may be fed via the previously mentioned flow path (transverse hole 24, chamber 22, transverse hole 25, tube duct 18, transverse hole 30 and chamber 32) to the conduit 11' and further through the hydraulic units 1', 1" and the conduits 11" and 11''' to the piston rod chamber of the unit 1"'.
- the piston 3"' is displaced from its outer end position to its inner end position. Since the clack valves in all mechanically locked pistons are open, the oil in the piston side chamber of the unit 1"' may be evacuated via the conduits 10"', 10" and 10 to the tank.
- the associated carrier 15 urges the auxiliary piston 39 into the associated course in the piston rod head of the adjacent hydraulic unit.
- each controlled hydraulic unit mechanically locks the associated piston rod in a fully pushed-out state as soon as the pushing-out of the piston rod in the outwardly adjacent hydraulic unit is started, a distinct and reliable sequential adjustment of the different telescopic boom sections is attained independently of whether the boom is extended or contracted.
- stiff or stationary hydraulic conduits may be arranged between co-operating units, for instance in the form of tubes.
- the two conduits between adjacent units are connected to on one hand only one piston rod head and on the other hand to only one cylinder.
- the invention makes it possible to connect an unlimited number of cylinders with each other for the adjustment of an arbitrary number of telescopic boom sections.
- the clack valve 27 in this case is opened by an auxiliary piston 43 that is provided in a chamber filled with a hydraulic medium in the form of grease.
- the pressure in the grease is increased so that the piston 43 is set in motion and distances the valve ball from its associated seat.
- the locking device 17 comprises three peripherically equidistantly separated, radially movable locking taps.
- the auxiliary piston 39 which is actuatable by a carrier 15 of an adjacent hydraulic unit and has the purpose of setting in motion the tube 16 that serves as a transmission element, in this case is placed at a certain distance from the part-chamber 37 in which the auxiliary piston 31 is movable.
- the positioning of the auxiliary piston 39 is not critical. On the contrary, it may be placed far distant from the piston rod head as such and be connected with the part-chamber 37 via a suitable conduit.
- auxiliary piston 31 is not connected to any spring (cf. spring 38 in figure 1), but instead influenced by the internal oil pressure in the piston rod 11 which is always striving at pushing the auxiliary piston towards the outer end position.
- the invention is not restricted only to the embodiments as described and shown in the drawings.
- it is feasible to provide a separate transmission element within the hollow piston rod, for adjusting the locking device although the tube serving as an intermediate conduit advantageously is used as a transmission element.
- Opening and closing of the clack valve in the main piston of the cylinder may be effected in another way than by means of the schematically shown spring 27' and auxiliary piston 43.
- the concrete design of the locking device 17 per se may be varied within wide limits.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Engineering & Computer Science (AREA)
- Actuator (AREA)
- Jib Cranes (AREA)
Claims (5)
- Flèche extensible, en particulier pour des grues, comportant plusieurs sections de flèche télescopiques qui peuvent être déplacées dans et hors l'une de l'autre au moyen d'unités hydrauliques à double effet (1), chacune comprenant séparément un cylindre (2) et une tige de piston creuse (4) avec un piston (3) qui divise l'intérieur du cylindre en deux chambres (5, 7), c'est-à-dire une chambre du côté piston (5) entre le piston et une première partie d'extrémité (6) du cylindre et une chambre de tige de piston (7) disposée entre le piston et une deuxième partie d'extrémité (8) avec un trou (9) à travers lequel la tige de piston (4) peut être déplacée de manière alternative, deux conduits principaux (10', 11'; 10", 11'') étant disposés entre des unités hydrauliques adjacentes qui coopèrent (1, 1'; 1', 1''), un premier (10', 10'') des conduits délivrant de l'huile ou un fluide hydraulique depuis une unité hydraulique interne (1, 1') à la chambre du côté piston (5) dans l'unité suivante à l'extérieur afin de pousser la tige de piston (4) hors du cylindre de la dernière unité (2), alors que l'autre conduit (11', 11'') délivre de l'huile à la chambre de tige de piston (7) dans le même cylindre depuis l'unité intérieure (1, 1') afin de pousser la tige de piston dedans, caractérisée en ce qu'un élément de transmission déplaçable (16) est placé à l'intérieur de la tige de piston creuse (4), lequel élément est, dans la zone d'une de ses extrémités, prévu pour actionner un dispositif de blocage (17) qui, dans un état actif, bloque le piston (3) et la tige de piston (4) dans un état axialement immobile par rapport au cylindre (2) lorsque la tige de piston (4) est poussée au maximum hors du cylindre, et qui, dans un état inactif, permet un déplacement de la tige de piston par rapport au cylindre, l'élément de transmission (16) étant, dans la zone de son extrémité opposée, au moins actionné indirectement par un support (15) qui suit de manière asservie les mouvements de la tige de piston (4) de l'unité hydraulique (1', 1'') disposée à l'extérieur suivante, plus spécialement d'une manière telle que le support (15) maintient le dispositif de blocage (17) dans l'état inactif par l'intermédiaire de l'élément de transmission (16) tant que la dernière tige de piston est dans sa position d'extrémité totalement rentrée, mais permet au dispositif de blocage (17) d'être actionné aussitôt que la tige de piston quitte cette position d'extrémité.
- Flèche selon la revendication 1, caractérisée en ce que le dispositif de blocage comporte au moins un robinet (17) qui est mobile radialement par rapport au piston (3) et prévu pour s'engager dans une position de blocage dans un siège (19) dans l'autre partie d'extrémité (8) du cylindre (2), plus spécialement par déplacement axial de l'élément de transmission déplaçable (16) dans une direction à l'écart du piston (3), un corps en coin (21) réglant le robinet dans un mouvement radial.
- Flèche selon la revendication 1 ou 2, caractérisée en ce que l'élément de transmission se compose d'un tube (16) qui sert de premier conduit intermédiaire pour l'alimentation en huile entre les chambres de tige de piston (7) des deux unités hydrauliques qui coopèrent, une cavité en forme de bague (13) entre l'extérieur du tube (16) et une partie tubulaire (12) de la tige de piston (4) servant de deuxième conduit intermédiaire pour l'alimentation en huile entre les chambres du côté piston (5) des unités.
- Flèche selon l'une quelconque des revendications précédentes, caractérisée en ce que, à son extrémité qui est à distance du piston principal (3) de l'unité hydraulique, l'élément de transmission (16) est relié à un premier piston auxiliaire (31) qui confine une extrémité d'une chambre (37) remplie avec un fluide hydraulique, par exemple de la graisse, laquelle chambre est prévue à l'intérieur d'une tête (14) sur l'extrémité libre de la tige de piston, et dont l'extrémité opposée est confinée par ou est reliée à un deuxième piston auxiliaire (39) qui est mobile dans et hors d'une course (40) par actionnement direct ou indirect par ledit support, et en ce que le premier piston auxiliaire (31) est actionné par une force de ressort qui essaie constamment d'éloigner l'élément de transmission (16) du piston principal (3) afin d'actionner le dispositif de blocage (17) et à l'encontre de l'action duquel le premier piston auxiliaire (31) est mobile dans la direction oppose lorsque le deuxième piston auxiliaire (39) est poussé dans la course associée pour l'inactivation du dispositif de blocage (17).
- Flèche selon l'une quelconque des revendications précédentes, caractérisée en ce qu'une soupape à clapet (27) est disposée dans le piston principal (3), laquelle soupape empêche une communication entre la chambre du côté piston (5) et l'autre conduit intermédiaire (13) tant que la tige de piston (4) est éloignée de sa position d'extrémité totalement repoussée à l'extérieur, mais qui est ouvert mécaniquement et automatiquement aussitôt que le piston atteint ladite position d'extrémité.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE9502099 | 1995-06-08 | ||
SE9502099A SE504463C2 (sv) | 1995-06-08 | 1995-06-08 | Förlängningsbar arm, särskilt för kranar |
PCT/SE1996/000606 WO1996041764A1 (fr) | 1995-06-08 | 1996-05-09 | Fleche extensible particulierement destinee a des grues |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0835220A1 EP0835220A1 (fr) | 1998-04-15 |
EP0835220B1 true EP0835220B1 (fr) | 2001-04-04 |
Family
ID=20398559
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP96915286A Expired - Lifetime EP0835220B1 (fr) | 1995-06-08 | 1996-05-09 | Fleche extensible particulierement destinee a des grues |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP0835220B1 (fr) |
AT (1) | ATE200266T1 (fr) |
AU (1) | AU5709596A (fr) |
DE (1) | DE69612380T2 (fr) |
SE (1) | SE504463C2 (fr) |
WO (1) | WO1996041764A1 (fr) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
ES2194560A1 (es) * | 2000-07-11 | 2003-11-16 | Partek Cargotec S A | Cilindro hidraulico para brazos telescopicos. |
DE102013012528A1 (de) * | 2013-07-27 | 2015-01-29 | Hydrosaar Gmbh | Druckversorgungseinrichtung |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
ITTO20010586A1 (it) * | 2001-06-18 | 2002-12-18 | Fassi Gru Idrauliche S P A | Dispositivo perfezionato di sfilamento e rientro sequenziali di sezioni di bracci telescopici di gru idrauliche. |
ATE393755T1 (de) | 2005-04-01 | 2008-05-15 | Cargotec Patenter Ab | Mehrstufiger teleskopausleger. |
AT12645U1 (de) | 2011-03-10 | 2012-09-15 | Palfinger Ag | Ladekran-ausleger |
CZ306692B6 (cs) * | 2015-11-03 | 2017-05-10 | ENTRACON s.r.o. | Teleskopické hydraulické vedení |
DE102017009183A1 (de) * | 2017-09-30 | 2019-04-04 | Walter Biedenbach | Kran |
CN109973463B (zh) * | 2019-04-22 | 2021-03-02 | 韶关市起重机厂有限责任公司 | 一种能可靠顺序伸缩的油缸、多油缸顺序伸缩机构及工程机械 |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3770138A (en) * | 1971-04-15 | 1973-11-06 | Fmc Corp | Sequenced crane boom |
US4433515A (en) * | 1981-11-04 | 1984-02-28 | Kidde, Inc. | Remotely operable latch and locking pin for a multi-section boom including a manual fly section |
AT398304B (de) * | 1991-11-11 | 1994-11-25 | Palfinger Ag | Mehrstufiger teleskopausleger |
-
1995
- 1995-06-08 SE SE9502099A patent/SE504463C2/sv not_active IP Right Cessation
-
1996
- 1996-05-09 WO PCT/SE1996/000606 patent/WO1996041764A1/fr active IP Right Grant
- 1996-05-09 EP EP96915286A patent/EP0835220B1/fr not_active Expired - Lifetime
- 1996-05-09 DE DE69612380T patent/DE69612380T2/de not_active Expired - Fee Related
- 1996-05-09 AU AU57095/96A patent/AU5709596A/en not_active Abandoned
- 1996-05-09 AT AT96915286T patent/ATE200266T1/de not_active IP Right Cessation
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
ES2194560A1 (es) * | 2000-07-11 | 2003-11-16 | Partek Cargotec S A | Cilindro hidraulico para brazos telescopicos. |
DE102013012528A1 (de) * | 2013-07-27 | 2015-01-29 | Hydrosaar Gmbh | Druckversorgungseinrichtung |
DE102013012528B4 (de) * | 2013-07-27 | 2015-09-24 | Hydrosaar Gmbh | Druckversorgungseinrichtung |
Also Published As
Publication number | Publication date |
---|---|
SE504463C2 (sv) | 1997-02-17 |
SE9502099D0 (sv) | 1995-06-08 |
DE69612380T2 (de) | 2001-09-13 |
WO1996041764A1 (fr) | 1996-12-27 |
EP0835220A1 (fr) | 1998-04-15 |
SE9502099L (sv) | 1996-12-09 |
AU5709596A (en) | 1997-01-09 |
DE69612380D1 (de) | 2001-05-10 |
ATE200266T1 (de) | 2001-04-15 |
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