EP1679284B1 - Telescopic lifting column - Google Patents
Telescopic lifting column Download PDFInfo
- Publication number
- EP1679284B1 EP1679284B1 EP05075090A EP05075090A EP1679284B1 EP 1679284 B1 EP1679284 B1 EP 1679284B1 EP 05075090 A EP05075090 A EP 05075090A EP 05075090 A EP05075090 A EP 05075090A EP 1679284 B1 EP1679284 B1 EP 1679284B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- cylinder
- lifting column
- piston unit
- piston
- operating 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.)
- Not-in-force
Links
Images
Classifications
-
- 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
- B66F3/00—Devices, e.g. jacks, adapted for uninterrupted lifting of loads
- B66F3/24—Devices, e.g. jacks, adapted for uninterrupted lifting of loads fluid-pressure operated
- B66F3/25—Constructional features
- B66F3/26—Adaptations or arrangements of pistons
- B66F3/28—Adaptations or arrangements of pistons telescopic
-
- 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
- F15B15/1404—Characterised by the construction of the motor unit of the straight-cylinder type in clusters, e.g. multiple cylinders in one block
Definitions
- the invention relates to a telescopic lifting column, comprising a plurality of tube bodies which are arranged concentrically inside one another and are axially movable in each case with respect to each other, and a hydraulic actuator unit which is arranged in the tube bodies so as to be operating in the axial direction.
- This actuator unit comprises a first hydraulic cylinder-piston unit and a second hydraulic cylinder-piston unit connected with the first, the first cylinder-piston unit being connected to a first end of the telescopic lifting column and the second cylinder-piston unit being connected to a second end of the telescopic lifting column, with the first cylinder-piston unit having a variable operating chamber and the second cylinder-piston unit having a variable operating chamber, said operating chambers being in communication with one another.
- US 2002/0144349 A1 shows a lifting column for an operating table.
- the lifting column has four tube bodies which are arranged concentrically inside one another and a hydraulic actuator unit.
- the actuator unit has two cylinder-piston units of the type where each has a first and a second variable operating chamber.
- the first cylinder-piston unit is connected to a base by means of a piston rod.
- the second cylinder-piston unit is connected to the table top by means of a piston rod.
- the first operating chamber of the first cylinder-piston unit is connectable to a pump or to a reservoir via a control valve.
- the first operating chambers of the first and second cylinder-piston units are connected to one another via a hydraulic line, so that the first operating chambers are simultaneously in communication with the pump or the reservoir.
- the second operating chamber of the second cylinder-piston unit is connectable to the pump and the reservoir via a valve.
- the second operating chambers of the first and second cylinder-piston units are likewise connected to one another via a hydraulic line, so that the second operating chambers are likewise simultaneously in communication with the pump or the reservoir.
- a consequence of the design of the cylinder-piston units of the known lifting column is that both the first and the second operating chambers have to be connectable to the pump and the reservoir and therefore at least one connection port and one supply/discharge line for hydraulic fluid have to be provided for each cylinder-piston unit. Furthermore, at least two control valves are required in order to be able to connect the operating chambers to the pump or to the reservoir.
- a lifting column with three tube bodies in which a hydraulic actuator unit is arranged.
- the hydraulic actuator unit has two cylinder-piston units of the double acting type, thus each of them having a first and a second operating chamber.
- the first operating chamber of the first cylinder-piston unit is connected to the first operating chamber of the second cylinder-piston unit.
- the second operating chamber of the first cylinder-piston unit is connected to the second operating chamber of the second cylinder-piston unit.
- the two operating chambers of the first cylinder-piston/unit are each, via an external connection, connected to a separate supply/discharge hose for supplying/discharging hydraulic fluid from the operating chambers.
- a lifting column according to the preamble of claim 1, characterized in that the first cylinder-piston unit is of the type having a first variable operating chamber and a second variable operating chamber, and the second cylinder-piston unit is of the type having a single variable operating chamber which is in communication with the second operating chamber of the first cylinder-piston unit.
- the operating chamber of the second cylinder-piston unit and the second operating chamber of the first cylinder-piston unit together therefore form a substantially closed space.
- a decrease in volume of the second operating chamber of the first cylinder-piston unit takes place and, as a result of the connection, an increase in volume of the operating chamber of the second cylinder-piston unit takes place.
- Only one external connection is required to push the pistons of the respective cylinder-piston units out or to pull them in in order to supply hydraulic fluid from a pump or to discharge it to a reservoir.
- the lifting column according to the invention requires less hydraulic fluid to achieve the same outward stroke because, in the known design, fluid from the operating chamber of which the volume is decreased during pushing out, is discharged to a reservoir without being utilized.
- the lifting column comprises three tube bodies, wherein the hydraulic actuator unit is connected to the middle tube body.
- the outermost tube sections are extended or retracted synchronously over an equal distance with respect to the middle tube section when the actuator unit is being operated. This results in a more stable lifting column capable of assuming any position between the completely extended state and the completely retracted state.
- Figs 1 and 2 show a telescopic lifting column 1 according to the invention in the completely retracted and the completely extended states.
- the preferred embodiment shown is designed to be used in an upright position.
- the lifting column 1 has a bottom tube section 2, a middle tube section 3 and a top tube section 4.
- the middle tube section 3 has a smaller outer diameter than the internal diameter of the bottom tube section 2.
- the top tube section 4 has a smaller outer diameter than the inner diameter of the middle tube section 3.
- the tube sections 2, 3, 4 are arranged concentrically inside one another.
- the sliding bearings 5 and 6 are provided on their underside with a radially inward flange 5a and 6a, respectively.
- a groove 10 is provided in the sliding bearing 5, which groove 10 extends in the axial direction.
- a projection 11 is arranged on the outer surface of the middle tube section 3, near the bottom thereof, which projection 11 is accommodated in the groove 10.
- a groove 12 is provided in the sliding bearing 6 , which groove 12 extends in the axial direction, and a projection 13 is arranged near the bottom of the top tube section 4, which projection 13 is accommodated in the groove 12.
- a sealing cap 7 is arranged at the top end of the bottom tube section 2 and with the outside bears against the inner surface of the bottom tube section 2 and with the inside bears against the outer surface of the middle tube section 3.
- the sealing cap 7 has a flange 7a which bears against the end side of the bottom tube section 2.
- the sealing cap 7 serves as a spacer between the bottom tube section 2 and the middle tube section 3.
- a sealing cap 8 having a flange 8a is arranged in an identical manner between the middle tube section 3 and the top tube section 4 and serves as a spacer between the middle tube section 3 and the top tube section 4.
- the bottom tube section 2 is provided with a base plate 14 which serves as a sealing cover for the underside of the bottom tube section 2.
- the top tube section 4 is provided with a cover plate 15 at the top.
- the lifting column 1 comprises a hydraulic actuator unit 20 which is arranged in the interior space delimited by the tube sections 2, 3, 4.
- the actuator unit 20 comprises a first cylinder-piston unit 30 having a cylinder 31 with a cylinder head 38 and extending in the axial direction of the tube sections 2-4, and a piston 32 arranged in the cylinder 31 and having a piston rod 33.
- a cylinder 41 of a second cylinder-piston unit 40 is arranged substantially parallel with and next to the cylinder 31 of the first cylinder-piston unit 30.
- the second cylinder-piston unit 40 has a piston 42 with a piston rod 43.
- the cylinders 31 and 41 are arranged in an upright position and next to one another on a base plate 21 and are fixedly attached to the latter, said base plate 21 in turn being fixedly mounted on the underside of the middle tube section 3.
- the piston rod 33 of the first cylinder-piston unit 30 extends through an aperture in the base plate 21 downwards and is connected by a bottom end 33a to a nipple 14a which is fitted on the base plate 14 of the bottom tube section 2, for example by means of a threaded connection.
- the piston rod 34 preferably extends at right angles to the bottom.
- the piston rod 43 of the second cylinder-piston unit 40 is connected to the cover plate 15 of the top tube section 4.
- the piston rod 33 and the piston 32 are provided with a supply/discharge duct 34, 35 for hydraulic fluid.
- a connection port 22 is arranged in the base plate 14, to which port a hydraulic line can be connected which joins the lifting column to a hydraulic assembly (not shown) comprising a pump, a reservoir and at least one control valve.
- a duct 23 is formed in the base plate 14, between the connection port 22 and the nipple 14a, connecting the connection port to the supply/discharge duct 34 in the piston rod 33.
- Hydraulic fluid can be supplied to and/or discharged from a first operating chamber 36 in the cylinder 31 via the supply/discharge duct 34, 35 in the piston 32 and piston rod 33, which first operating chamber 36 is delimited by the cylinder wall, the cylinder head 38 and the piston 32.
- the first cylinder-piston unit 30 has a second operating chamber 37 which is delimited by the cylinder wall, the piston 32, the piston rod 34 and the base plate 21 which is connected to the middle tube section.
- the second operating chamber 37 is at a maximum volume and the first operating chamber 36 at a minimum volume.
- the first operating chamber is at a maximum volume and the second operating chamber 37 at a minimum volume.
- the second cylinder-piston unit 40 is of the type which has only one operating chamber 47.
- the operating chamber 47 of the second cylinder-piston unit 40 is connected to the second operating chamber 37 of the first cylinder-piston unit 30 via a duct 24 which is arranged in the base plate 21.
- the operating chamber 47 of the second cylinder-piston unit 40 and the second operating chamber 37 of the first cylinder-piston unit 30 in principle form a closed entity and together have a constant volume.
- the first cylinder-piston unit 30 and the second cylinder-piston unit 40 have an identical stroke length and the maximum volume of the operating chamber 47 (see Fig. 2 ) is equal to the maximum volume of the second operating chamber 37 (see Fig. 1 ).
- the second cylinder 41 having an inner diameter which corresponds to the difference between the inner diameter of the first cylinder 31 and the outer diameter of the piston rod 34. This means that it is possible to push the cylinder-piston units 30, 40 out at a constant and uniform speed, independently of the load.
- the total length of the lifting column in the completely retracted state could be approximately 35 cm, for example, and in the completely extended state ( Fig. 2 ) approximately 75 cm.
- the first and second cylinder-piston units 30, 40 each have a length of stroke of 20 cm.
- a bypass 39 is provided at the bottom end of the cylinder 31 of the first cylinder-piston unit 30, by which hydraulic fluid can flow along the piston 32 of the first operating chamber 36 to the second operating chamber 37 when the piston is near the end of the stroke, as is indicated in Fig. 2 .
- the bypass 39 by way of example, is in the shape of a small recess on the inside of the cylinder wall, but may, for example, also be designed as a duct.
- the purpose of the bypass 39 is to prevent the second operating chamber not being filled to its maximum volume as a result of hydraulic oil leaking out of the second operating chamber 37 and the operating chamber 47 if the gasket is not completely sealed. Any shortfall in oil is supplemented via the bypass 39 and the telescopic lifting column 1 can thus still reach its maximum extended state despite the losses due to leakage.
- a discharge duct 27 is arranged in the base plate 21 and serves for discharging hydraulic fluid which has leaked from the hydraulic actuator unit 20 onto the base plate 21 down towards the bottom tube section.
- a discharge duct 25 is arranged in the base plate 14 and is connected to a discharge port 26 in order to discharge hydraulic fluid which has leaked onto the base plate 14 to a reservoir.
- hydraulic fluid is supplied under pressure via connection port 22 and supply/discharge ducts 23, 34 and 35 to the first operating chamber 36.
- the first operating chamber 36 increases in volume and the cylinder 31 is pushed upwards with respect to the piston 32 while carrying the base plate 21 along.
- the volume of the second operating chamber 37 decreases and hydraulic fluid is pumped from the second operating chamber 37 to the operating chamber 47 of the second cylinder-piston unit via the duct 24, as a result of which the operating chamber 47 increases in volume and the piston 42 inside the cylinder 41 is pushed upwards, by which the top tube section 4 which is connected to the piston rod 43 is moved upwards with respect to the cylinder 41.
- the projection 11 is positioned against a bottom edge of the groove 10 in the sliding bearing 5.
- the projection 13 is likewise positioned against a bottom edge of the groove 12 in the sliding bearing 6.
- the first operating chamber 36 can be connected to a reservoir via the connection port 22 and the ducts 35, 34 and 23. This leads to a loss of pressure in the first operating chamber 36, causing the lifting column 1 to be pushed into one another by the effect of the load which is acting on them.
- hydraulic fluid flows from the operating chamber 47 of the second cylinder-piston unit 40 to the second operating chamber of the first cylinder-piston unit 30 via the duct 24. Furthermore, hydraulic fluid flows from the first operating chamber 36 to the reservoir.
- the projections 13 and 11, respectively, are guided downwards in the associated grooves 12 and 10, respectively, until they reach the bottom edge of the grooves 12 and 10, respectively, after which the sliding bearings 6 and 5, respectively, are pulled along downwards by the tube sections 4 and 3, respectively.
- the sliding bearings 5, 6 which slide along concomitantly have a positive effect on the rigidity of the lifting column 1.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Structural Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Engineering & Computer Science (AREA)
- Actuator (AREA)
- Vibration Dampers (AREA)
- Vehicle Body Suspensions (AREA)
- Forklifts And Lifting Vehicles (AREA)
Abstract
Description
- The invention relates to a telescopic lifting column, comprising a plurality of tube bodies which are arranged concentrically inside one another and are axially movable in each case with respect to each other, and a hydraulic actuator unit which is arranged in the tube bodies so as to be operating in the axial direction. This actuator unit comprises a first hydraulic cylinder-piston unit and a second hydraulic cylinder-piston unit connected with the first, the first cylinder-piston unit being connected to a first end of the telescopic lifting column and the second cylinder-piston unit being connected to a second end of the telescopic lifting column, with the first cylinder-piston unit having a variable operating chamber and the second cylinder-piston unit having a variable operating chamber, said operating chambers being in communication with one another.
- A lifting column of this type is known.
US 2002/0144349 A1 shows a lifting column for an operating table. The lifting column has four tube bodies which are arranged concentrically inside one another and a hydraulic actuator unit. The actuator unit has two cylinder-piston units of the type where each has a first and a second variable operating chamber. The first cylinder-piston unit is connected to a base by means of a piston rod. The second cylinder-piston unit is connected to the table top by means of a piston rod. The first operating chamber of the first cylinder-piston unit is connectable to a pump or to a reservoir via a control valve. The first operating chambers of the first and second cylinder-piston units are connected to one another via a hydraulic line, so that the first operating chambers are simultaneously in communication with the pump or the reservoir. The second operating chamber of the second cylinder-piston unit is connectable to the pump and the reservoir via a valve. The second operating chambers of the first and second cylinder-piston units are likewise connected to one another via a hydraulic line, so that the second operating chambers are likewise simultaneously in communication with the pump or the reservoir. When the volume of the first operating chambers increases, the distance of the table top to the floor surface increases. - A consequence of the design of the cylinder-piston units of the known lifting column is that both the first and the second operating chambers have to be connectable to the pump and the reservoir and therefore at least one connection port and one supply/discharge line for hydraulic fluid have to be provided for each cylinder-piston unit. Furthermore, at least two control valves are required in order to be able to connect the operating chambers to the pump or to the reservoir.
- In
AU-B-452690 - It is an object of the invention to provide an improved lifting column of simplified design.
- This object is achieved by a lifting column according to the preamble of claim 1, characterized in that the first cylinder-piston unit is of the type having a first variable operating chamber and a second variable operating chamber, and the second cylinder-piston unit is of the type having a single variable operating chamber which is in communication with the second operating chamber of the first cylinder-piston unit.
- According to the invention, the operating chamber of the second cylinder-piston unit and the second operating chamber of the first cylinder-piston unit together therefore form a substantially closed space. When the first operating chamber of the first cylinder-piston unit increases in volume, a decrease in volume of the second operating chamber of the first cylinder-piston unit takes place and, as a result of the connection, an increase in volume of the operating chamber of the second cylinder-piston unit takes place. Only one external connection is required to push the pistons of the respective cylinder-piston units out or to pull them in in order to supply hydraulic fluid from a pump or to discharge it to a reservoir. As a result, in principle only one control valve or valve assembly is required to be able to connect to first operating chamber of the first cylinder-piston unit to the pump or to the reservoir. Furthermore, compared to the known design according to
US 2002/0144349 and alsoAU-B-452 690 - According to a preferred embodiment of the invention the lifting column comprises three tube bodies, wherein the hydraulic actuator unit is connected to the middle tube body.
- As a result of this design of the lifting column, the outermost tube sections are extended or retracted synchronously over an equal distance with respect to the middle tube section when the actuator unit is being operated. This results in a more stable lifting column capable of assuming any position between the completely extended state and the completely retracted state.
- The invention will be explained in more detail using a preferred embodiment and with reference to the drawing, in which:
-
Fig. 1 shows a longitudinal cross section of a preferred embodiment of a lifting column according to the invention in the completely retracted state, -
Fig. 2 shows a longitudinal cross section of the lifting column ofFig. 1 in the completely extended state, and -
Fig. 3 shows a cross section of the lifting column on line III-III ofFig. 1 . -
Figs 1 and 2 show a telescopic lifting column 1 according to the invention in the completely retracted and the completely extended states. The preferred embodiment shown is designed to be used in an upright position. In this preferred embodiment, the lifting column 1 has abottom tube section 2, amiddle tube section 3 and atop tube section 4. Themiddle tube section 3 has a smaller outer diameter than the internal diameter of thebottom tube section 2. Thetop tube section 4 has a smaller outer diameter than the inner diameter of themiddle tube section 3. In the completely retracted state (Fig. 1 ), thetube sections - A substantially sleeve-shaped sliding bearing 5, which is slideable with respect to the two
tube sections tube sections tube sections tube sections bearings groove 10 is provided in the sliding bearing 5, whichgroove 10 extends in the axial direction. Aprojection 11 is arranged on the outer surface of themiddle tube section 3, near the bottom thereof, whichprojection 11 is accommodated in thegroove 10. In an identical manner, agroove 12 is provided in the sliding bearing 6 , whichgroove 12 extends in the axial direction, and aprojection 13 is arranged near the bottom of thetop tube section 4, whichprojection 13 is accommodated in thegroove 12. - A sealing cap 7 is arranged at the top end of the
bottom tube section 2 and with the outside bears against the inner surface of thebottom tube section 2 and with the inside bears against the outer surface of themiddle tube section 3. The sealing cap 7 has aflange 7a which bears against the end side of thebottom tube section 2. The sealing cap 7 serves as a spacer between thebottom tube section 2 and themiddle tube section 3. Near the top end of themiddle tube section 3, asealing cap 8 having aflange 8a is arranged in an identical manner between themiddle tube section 3 and thetop tube section 4 and serves as a spacer between themiddle tube section 3 and thetop tube section 4. - The
bottom tube section 2 is provided with abase plate 14 which serves as a sealing cover for the underside of thebottom tube section 2. Thetop tube section 4 is provided with acover plate 15 at the top. - The lifting column 1 comprises a
hydraulic actuator unit 20 which is arranged in the interior space delimited by thetube sections actuator unit 20 comprises a first cylinder-piston unit 30 having acylinder 31 with acylinder head 38 and extending in the axial direction of the tube sections 2-4, and apiston 32 arranged in thecylinder 31 and having a piston rod 33. Acylinder 41 of a second cylinder-piston unit 40 is arranged substantially parallel with and next to thecylinder 31 of the first cylinder-piston unit 30. The second cylinder-piston unit 40 has apiston 42 with apiston rod 43. Thecylinders base plate 21 and are fixedly attached to the latter, saidbase plate 21 in turn being fixedly mounted on the underside of themiddle tube section 3. - The piston rod 33 of the first cylinder-
piston unit 30 extends through an aperture in thebase plate 21 downwards and is connected by abottom end 33a to anipple 14a which is fitted on thebase plate 14 of thebottom tube section 2, for example by means of a threaded connection. Thepiston rod 34 preferably extends at right angles to the bottom. Thepiston rod 43 of the second cylinder-piston unit 40 is connected to thecover plate 15 of thetop tube section 4. - The piston rod 33 and the
piston 32 are provided with a supply/discharge duct connection port 22 is arranged in thebase plate 14, to which port a hydraulic line can be connected which joins the lifting column to a hydraulic assembly (not shown) comprising a pump, a reservoir and at least one control valve. Aduct 23 is formed in thebase plate 14, between theconnection port 22 and thenipple 14a, connecting the connection port to the supply/discharge duct 34 in the piston rod 33. - Hydraulic fluid can be supplied to and/or discharged from a
first operating chamber 36 in thecylinder 31 via the supply/discharge duct piston 32 and piston rod 33, whichfirst operating chamber 36 is delimited by the cylinder wall, thecylinder head 38 and thepiston 32. The first cylinder-piston unit 30 has asecond operating chamber 37 which is delimited by the cylinder wall, thepiston 32, thepiston rod 34 and thebase plate 21 which is connected to the middle tube section. InFig. 1 , thesecond operating chamber 37 is at a maximum volume and thefirst operating chamber 36 at a minimum volume. InFig. 2 , the first operating chamber is at a maximum volume and thesecond operating chamber 37 at a minimum volume. - The second cylinder-
piston unit 40 is of the type which has only oneoperating chamber 47. The operatingchamber 47 of the second cylinder-piston unit 40 is connected to thesecond operating chamber 37 of the first cylinder-piston unit 30 via aduct 24 which is arranged in thebase plate 21. The operatingchamber 47 of the second cylinder-piston unit 40 and thesecond operating chamber 37 of the first cylinder-piston unit 30 in principle form a closed entity and together have a constant volume. Preferably, the first cylinder-piston unit 30 and the second cylinder-piston unit 40 have an identical stroke length and the maximum volume of the operating chamber 47 (seeFig. 2 ) is equal to the maximum volume of the second operating chamber 37 (seeFig. 1 ). This is achieved by thesecond cylinder 41 having an inner diameter which corresponds to the difference between the inner diameter of thefirst cylinder 31 and the outer diameter of thepiston rod 34. This means that it is possible to push the cylinder-piston units - In a practical embodiment, the total length of the lifting column in the completely retracted state (
Fig. 1 ) could be approximately 35 cm, for example, and in the completely extended state (Fig. 2 ) approximately 75 cm. In that case, the first and second cylinder-piston units - A
bypass 39 is provided at the bottom end of thecylinder 31 of the first cylinder-piston unit 30, by which hydraulic fluid can flow along thepiston 32 of thefirst operating chamber 36 to thesecond operating chamber 37 when the piston is near the end of the stroke, as is indicated inFig. 2 . In this embodiment, thebypass 39, by way of example, is in the shape of a small recess on the inside of the cylinder wall, but may, for example, also be designed as a duct. The purpose of thebypass 39 is to prevent the second operating chamber not being filled to its maximum volume as a result of hydraulic oil leaking out of thesecond operating chamber 37 and the operatingchamber 47 if the gasket is not completely sealed. Any shortfall in oil is supplemented via thebypass 39 and the telescopic lifting column 1 can thus still reach its maximum extended state despite the losses due to leakage. - A
discharge duct 27 is arranged in thebase plate 21 and serves for discharging hydraulic fluid which has leaked from thehydraulic actuator unit 20 onto thebase plate 21 down towards the bottom tube section. Adischarge duct 25 is arranged in thebase plate 14 and is connected to adischarge port 26 in order to discharge hydraulic fluid which has leaked onto thebase plate 14 to a reservoir. - In use, with the lifting column in the completely retracted state (
Fig. 1 ), hydraulic fluid is supplied under pressure viaconnection port 22 and supply/discharge ducts first operating chamber 36. As a result, thefirst operating chamber 36 increases in volume and thecylinder 31 is pushed upwards with respect to thepiston 32 while carrying thebase plate 21 along. At the same time, the volume of thesecond operating chamber 37 decreases and hydraulic fluid is pumped from thesecond operating chamber 37 to the operatingchamber 47 of the second cylinder-piston unit via theduct 24, as a result of which theoperating chamber 47 increases in volume and thepiston 42 inside thecylinder 41 is pushed upwards, by which thetop tube section 4 which is connected to thepiston rod 43 is moved upwards with respect to thecylinder 41. - In the completely retracted state of
Fig. 1 , theprojection 11 is positioned against a bottom edge of thegroove 10 in the slidingbearing 5. Theprojection 13 is likewise positioned against a bottom edge of thegroove 12 in the slidingbearing 6. When the top tube section moves upwards, theprojection 13 will be guided upwards through thegroove 12 until it hits the top edge of thegroove 12, after which the slidingbearing 6 will be moved upwards by theprojection 13 with respect to themiddle tube section 3. Theprojection 11 on themiddle tube body 3 will be guided upwards through thegroove 10 in a similar way until it hits the top edge of thegroove 10, after which the slidingbearing 5 will be moved upwards by themiddle tube body 3 and displaced upwards with respect to thebottom tube body 2. - When the lifting column 1 is in the completely extended state according to
Fig. 2 , thefirst operating chamber 36 can be connected to a reservoir via theconnection port 22 and theducts first operating chamber 36, causing the lifting column 1 to be pushed into one another by the effect of the load which is acting on them. In the process, hydraulic fluid flows from the operatingchamber 47 of the second cylinder-piston unit 40 to the second operating chamber of the first cylinder-piston unit 30 via theduct 24. Furthermore, hydraulic fluid flows from thefirst operating chamber 36 to the reservoir. Theprojections grooves grooves bearings tube sections bearings
Claims (13)
- Telescopic lifting column (1), comprising:- a plurality of tube bodies (2,3,4) which are arranged concentrically inside one another and are axially movable in each case with respect to each other,- a hydraulic actuator unit (20) which is arranged in the tube bodies (2, 3, 4) so as to be operating in the axial direction, comprising a first hydraulic cylinder-piston unit (30) and a second hydraulic cylinder-piston unit (40) connected with the first, the first cylinder-piston unit (30) being connected to a first end of the telescopic lifting column and the second cylinder-piston unit being connected to a second end of the telescopic lifting column (1), in which the first cylinder-piston unit (30) as a variable operating chamber (37) and the second cylinder-piston unit (40) has a variable operating chamber (47), said operating chambers (37,47) being interconnected,wherein the first cylinder-piston unit (30) is of the type having a first variable operating chamber (36) and a second variable operating chamber (37), and characterized in that the second cylinder piston unit (40) is of the type having a single variable operating chamber (47) which is in communication with the second operating chamber (37) of the first cylinder-piston unit (30).
- Telescopic lifting column according to claim 1, in which a bypass (29) is arranged in the first cylinder-piston unit (30), in the region of the end of the piston stroke, where the volume of the second operating chamber (37) is minimal, which bypass (39) connects the first and second operating chambers (36,37) of the first cylinder-piston unit (30) with one another.
- Telescopic lifting column according to claim 1 or 2, in which the piston rod (33) and the piston (32) of the first cylinder-piston unit (30) are provided with a supply duct (34,35) for supplying hydraulic fluid to the first operating chamber (36).
- Telescopic lifting column according to claim 3, in which the first end of the telescopic column (1) is provided with a first cover plate (14) on which the piston rod (33) of the first cylinder-piston unit (30) is mounted substantially at right angles thereto.
- Telescopic lifting column according to claim 4, in which the first cover plate (14) is provided with a connection port (22) and a fluid duct (23) connected thereto, the latter being connected to the supply duct (34) in the piston rod (33).
- Telescopic lifting column according to claim 4 or 5, in which the second end of the telescopic column is provided with a second cover plate (15) on which the piston rod (43) of the second cylinder-piston unit (40) is mounted substantially at right angles thereto.
- Telescopic column according to one of the preceding claims, in which the first cylinder-piston unit (30) and the second cylinder-piston unit (40) have an identical stroke length and the maximum volume of the operating chamber (47) of the second cylinder-piston unit (40) is equal to the maximum volume of the second operating chamber (37) of the first cylinder-piston unit (30).
- Telescopic column according to one of the preceding claims, in which the first end of the lifting column (1) is designed to be placed on a base.
- Telescopic lifting column according to one of the preceding claims, in which the lifting column (1) comprises three tube bodies (2,3,4) the hydraulic actuator unit (20) being connected to the middle tube body (3).
- Telescopic lifting column according to claim 9, in which the cylinders (31,41) of the hydraulic actuator unit (20) are fixedly connected to the middle tube body (3).
- Telescopic lifting column according to claim 9 or 10, in as far as dependent on claim 8, in which the middle tube body (3) has a base plate (21) on which the first and second cylinders (31,41) rest.
- Telescopic lifting column according to claim 11, in which the base plate (21) of the middle tube body (3) is provided with a return duct (27) for discharging the hydraulic fluid, which has leaked from the actuator unit (20) to the bottom tube body (2).
- Telescopic lifting column according to claim 12, in which the first cover plate (14) is provided with a return duct (25) for discharging hydraulic fluid which has leaked from the actuator unit (20), from the bottom tube body (2) to a reservoir.
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT05075090T ATE399738T1 (en) | 2005-01-11 | 2005-01-11 | TELESCOPIC LIFTING COLUMN |
DK05075090T DK1679284T3 (en) | 2005-01-11 | 2005-01-11 | Telescopic lifting column |
EP05075090A EP1679284B1 (en) | 2005-01-11 | 2005-01-11 | Telescopic lifting column |
DE602005007849T DE602005007849D1 (en) | 2005-01-11 | 2005-01-11 | Telescopic lifting column |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP05075090A EP1679284B1 (en) | 2005-01-11 | 2005-01-11 | Telescopic lifting column |
Publications (2)
Publication Number | Publication Date |
---|---|
EP1679284A1 EP1679284A1 (en) | 2006-07-12 |
EP1679284B1 true EP1679284B1 (en) | 2008-07-02 |
Family
ID=34937993
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP05075090A Not-in-force EP1679284B1 (en) | 2005-01-11 | 2005-01-11 | Telescopic lifting column |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP1679284B1 (en) |
AT (1) | ATE399738T1 (en) |
DE (1) | DE602005007849D1 (en) |
DK (1) | DK1679284T3 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101581354B (en) * | 2008-04-21 | 2012-01-11 | 梅西耶-布加蒂公司 | Actuator with main rod and auxiliary rod |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2936292B1 (en) * | 2008-09-25 | 2011-07-22 | Messier Bugatti | TELESCOPIC ACTUATOR WITH MAIN ROD AND AUXILIARY ROD |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AU452690B2 (en) * | 1970-11-17 | 1974-08-27 | Cranes And Shovels Proprietary Limited | Fluid operable extensible device |
GB2176845B (en) * | 1985-06-21 | 1989-04-26 | 600 Group Plc The | Improvements in telescopic devices such as crane jibs |
JP2005500083A (en) * | 2001-01-25 | 2005-01-06 | ヒル−ロム サービシーズ,インコーポレイティド | Hydraulic actuator device for surgical table |
-
2005
- 2005-01-11 DE DE602005007849T patent/DE602005007849D1/en active Active
- 2005-01-11 DK DK05075090T patent/DK1679284T3/en active
- 2005-01-11 EP EP05075090A patent/EP1679284B1/en not_active Not-in-force
- 2005-01-11 AT AT05075090T patent/ATE399738T1/en not_active IP Right Cessation
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101581354B (en) * | 2008-04-21 | 2012-01-11 | 梅西耶-布加蒂公司 | Actuator with main rod and auxiliary rod |
Also Published As
Publication number | Publication date |
---|---|
ATE399738T1 (en) | 2008-07-15 |
DE602005007849D1 (en) | 2008-08-14 |
EP1679284A1 (en) | 2006-07-12 |
DK1679284T3 (en) | 2008-10-20 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7171890B2 (en) | Telescopic lifting device | |
US2933070A (en) | Double-acting hydraulic jack | |
US4726281A (en) | Hydraulic cylinder | |
JP5881144B2 (en) | lift device | |
CA2246863C (en) | One-side fed, double-acting, pneumatic actuator | |
KR101653839B1 (en) | Device for proportioned distribution of lubricant | |
WO2006089582A8 (en) | Piston/cylinder unit | |
FI70302B (en) | HYDRAULISK STYRVENTIL | |
US6247307B1 (en) | Hydraulic raising apparatus with automatic regulated speeds | |
SE504248C2 (en) | Gear maneuvering device | |
US20130008538A1 (en) | Valve for alternately filling two working chambers of a piston-cylinder system of a pump | |
US10895269B2 (en) | Double acting hydraulic pressure intensifier | |
US20130284010A1 (en) | Telescopic cylinder | |
US6851349B2 (en) | Bleederless telescopic cylinder | |
EP1679284B1 (en) | Telescopic lifting column | |
JPH11500516A (en) | Hydraulic intensifier | |
US20110036084A1 (en) | Vehicle cab tilting device with telescopic tilting cylinder | |
CA2674961C (en) | Positive displacement pump apparatus | |
US7685927B1 (en) | Hydraulic synchronizing cylinder | |
CN109268322A (en) | Energy-storage hydraulic device | |
JP2002070809A (en) | Double-acting multistage cylinder | |
JP2015158258A (en) | Double motion type fluid pressure cylinder | |
JP6564225B2 (en) | Control valve | |
CN210087728U (en) | Telescopic cylinder and telescopic bracket | |
KR101379794B1 (en) | 3-position controlling type hydraulic or pneumatic cylinder |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU MC NL PL PT RO SE SI SK TR |
|
AX | Request for extension of the european patent |
Extension state: AL BA HR LV MK YU |
|
17P | Request for examination filed |
Effective date: 20061206 |
|
17Q | First examination report despatched |
Effective date: 20070116 |
|
AKX | Designation fees paid |
Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU MC NL PL PT RO SE SI SK TR |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU MC NL PL PT RO SE SI SK TR |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: EP |
|
REF | Corresponds to: |
Ref document number: 602005007849 Country of ref document: DE Date of ref document: 20080814 Kind code of ref document: P |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: SE Ref legal event code: TRGR |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20080702 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20080702 |
|
NLV1 | Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act | ||
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20080702 Ref country code: IS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20081102 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: ES Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20081013 Ref country code: AT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20080702 Ref country code: BG Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20081002 Ref country code: FI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20080702 Ref country code: PT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20081202 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: BE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20080702 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: EE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20080702 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20080702 Ref country code: RO Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20080702 |
|
26N | No opposition filed |
Effective date: 20090403 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: MC Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20090131 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20090111 |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: MM4A |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LI Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20090131 Ref country code: CH Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20090131 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20090111 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20090111 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: PL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20080702 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: IT Payment date: 20100127 Year of fee payment: 6 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20081003 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LU Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20090111 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: HU Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20090103 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: TR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20080702 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: CY Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20080702 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20110111 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: PLFP Year of fee payment: 11 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DK Payment date: 20150126 Year of fee payment: 11 Ref country code: DE Payment date: 20150128 Year of fee payment: 11 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: SE Payment date: 20150128 Year of fee payment: 11 Ref country code: FR Payment date: 20150119 Year of fee payment: 11 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: CZ Payment date: 20160302 Year of fee payment: 12 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R119 Ref document number: 602005007849 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: DK Ref legal event code: EBP Effective date: 20160131 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST Effective date: 20160930 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20160802 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20160112 Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20160201 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DK Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20160131 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: CZ Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20170111 |