DE102018209089A1 - Piston-cylinder unit and telescopic column, in particular for a seat-upright furniture, comprising a piston-cylinder unit - Google Patents

Abstract

The present invention relates to a piston-cylinder unit (10), comprising a first cylinder (12) having a first cylinder longitudinal axis, a first piston assembly (14) inserted into the first cylinder (12) and having a first piston rod (16) first cylinder (12) at a first end face (S1-1) passes through, and a first piston (18), which interior of the first cylinder (12) in a first working space (A1-1) and a second working space (A2-1 ), wherein the first working space (A1-1) on one side of the first end face (S1 -1) is arranged and the second working space (A2-1) on one side of the first end face (S1-1) opposite the second end face ( S2-1) of the first cylinder (12) is arranged, a second cylinder (22) with a substantially parallel to the first cylinder longitudinal axis aligned second cylinder longitudinal axis and in the second cylinder (22) inserted second piston assembly (24) with a second n piston rod (26), which passes through the second cylinder (22) on one of the first end face (S1-1) of the first cylinder (12) opposite the second end face (S2-2) of the second cylinder (22), and a second piston ( 28) dividing an interior of the second cylinder (22) into a first working space (A1-2) and a second working space (A2-2), the second working space (A1-2) of the second cylinder (22) being on one side the second end face (S2-2) of the second cylinder (22) is arranged and the first working space (A1-2) of the second cylinder (22) on one side of the second end face (S2-2) of the second cylinder (22) opposite the first end face (S1-2) of the second cylinder (22) is arranged, wherein the first piston (18) or the second piston (28) comprises a valve (30) which is adapted to the first in an open state Working space (A1-1, A1-2) and the second working space (A2-1, A2-2) of the respective cylinder rs (12, 22) with each other, wherein the piston-cylinder unit (10) is arranged such that a fluid exchange between the first working space (A1-1) of the first cylinder (12) and the second working space (A2-2) of

Description

The present invention relates to a piston-cylinder unit, comprising a first cylinder having a first cylinder longitudinal axis, a first piston assembly inserted into the first cylinder having a first piston rod, which passes through the first cylinder at a first end face, and a first piston, which Interior of the first cylinder into a first working space and a second working space, wherein the first working space is disposed on one side of the first end face and the second working space is disposed on a side of the first end face opposite second end face of the first cylinder, a second cylinder with a second cylinder longitudinal axis aligned substantially parallel to the first cylinder longitudinal axis and a second piston assembly inserted into the second cylinder having a second piston rod, which adjusts the second cylinder to one of the first end face of the first cylinder a second piston, which divides an inside of the second cylinder into a first working space and a second working space, wherein the second working space of the second cylinder is arranged on one side of the second end face of the second cylinder and the first working space of the second cylinder is disposed on one side of a second end face of the second cylinder opposite to the second end face of the second cylinder. Furthermore, the present invention relates to a telescopic column comprising a piston-cylinder unit.

For example, in office workstations, it is sometimes desirable to provide, in addition to conventional office chairs or office swivel chairs, also standing aids which, in conjunction with height-adjustable tables, can for example improve a user's posture, relieve the back or simply provide an alternative work position.

According to the current state of the art, there are either office swivel chairs or standing aids with respective adjusting elements for small or medium adjustment paths in the chairs and correspondingly larger adjustment paths in the standing aids. The adjustment elements cover either the sitting or the standing area.

So it will require two different products to allow both a sitting function as well as a standing function.

Against this background, it is an object of the present invention to provide an adjustment with a relative to a retracted length particularly large adjustment or stroke. It is also an object of the present invention, an adjusting for a piece of furniture, which is suitable both as seating and as a standing furniture to provide, with which by a correspondingly large adjustment on the one hand low seat heights, on the other hand, but also heights, which is a function of Furniture as a standing aid allow, can be achieved.

According to a first aspect, the object of the invention is achieved by a piston-cylinder unit, comprising a first cylinder having a first cylinder longitudinal axis, a first piston assembly inserted into the first cylinder with a first piston rod, which passes through the first cylinder at a first end face, and a a first piston dividing an interior of the first cylinder into a first working space and a second working space, wherein the first working space is disposed on one side of the first end surface and the second working space is located on a side of a second end surface of the first cylinder opposite the first end surface a second cylinder having a second cylinder longitudinal axis aligned substantially parallel to the first cylinder longitudinal axis; and a second piston assembly having a second piston rod inserted into the second cylinder and supporting the second cylinder on one of the first end faces of the first cylinder a second piston, which divides an inside of the second cylinder into a first working space and a second working space, the second working space of the second cylinder being arranged on one side of the second end face of the second cylinder and the first working space of the second cylinder is disposed on one side of a first end face of the second cylinder opposite the second end face of the second cylinder, the first piston or the second piston having a valve arranged to open the first one Working space and the second working space of the respective cylinder with each other, and wherein the piston-cylinder unit is arranged such that a fluid exchange between the first working space of the first cylinder and the second working space of the second cylinder is enabled and / or Fluid exchange between the first working space of the second cylinder and the second working space of the first cylinder is made possible.

The fact that a piston of the piston-cylinder unit has a valve and the other piston of the piston-cylinder unit has no valve, a fluid exchange is also possible with a working space of the other cylinder, however, the two oppositely directed piston arrangements (first and second piston assembly) as a single piston assembly, but with a longer stroke.

A maximum achievable stroke of the piston-cylinder unit is greater than their retracted length. As a result, the piston-cylinder unit according to the invention is suitable for many applications in which a relatively compact adjustment is required with a length in relation to the retracted length very large stroke, in particular for example as adjustment for a piece of furniture, both as a chair and as a standing aid should be used. Such a piece of furniture is hereinafter also referred to as sitting-upright furniture.

It should be noted that the term "cylinder" is not to be considered limiting to a cylinder member, but rather includes any "cylindrical cavity". For example, the first piston assembly and the second piston assembly may also be inserted into respective cylinder cavities that may be provided within a common housing.

Furthermore, it should be noted that the term "substantially parallel" here explicitly also includes arrangements in which the cylinder longitudinal axis of the first and second cylinders are arranged at a small angle of approximately up to 15 ° to each other.

In particular, the first working space of the first cylinder can be connected to the second working space of the second cylinder via at least one first connecting channel and / or the first working space of the second cylinder can be connected to the second working space of the first cylinder via at least one second connecting passage. Fluid exchange of the working fluid may thereby take place in a relatively direct way and, for example, by defining the cross-section of the at least one first connection channel and the at least one second connection channel in a predefined manner. The term "connecting channel" is to be understood here as meaning that a fluid exchange is made possible by the connecting channel or the connecting channels. That is, the term "communicating channel" is not to be understood as limiting to components such as pipes or hoses, but rather implies any "channel-like" clearance interconnecting the respective work spaces

The piston having the valve may comprise an actuating part which is adapted to open the valve when it is actuated and to close the valve when it is not actuated. In this way, a particularly favorable possibility of operating or switching the piston-cylinder unit can be ensured. Upon actuation of the operating part, the piston rods can extend and retract, the operating part is not actuated, the piston-cylinder unit may be resiliently blocked.

Particularly preferably, a maximum stroke of the piston-cylinder unit can be greater than a length of the retracted piston-cylinder unit, preferably, the maximum stroke of the piston-cylinder unit can be substantially twice the length of the retracted piston-cylinder unit. By this property, the piston-cylinder unit is ideal, for example, especially suitable for use as an adjustment for a seat-upright furniture, which requires a relatively compact retracted length of the adjustment and a relatively large stroke.

In a particularly preferred embodiment, a maximum stroke of the piston-cylinder unit may be at least 300 mm, preferably about 440 mm. This relatively large stroke or adjustment is advantageous for use as an adjusting element for a piece of furniture, which is to be used both as a chair and as a standing aid.

In addition, the first piston rod of the first piston assembly may have substantially the same diameter as the second piston rod of the second piston assembly. Likewise, the first piston of the first piston assembly may have substantially the same diameter as the second piston of the second piston assembly. If both piston rods and both pistons have substantially the same diameter, then both piston assemblies also produce substantially the same extension and locking forces and both piston rods can extend and retract substantially simultaneously and at substantially the same speed. However, it is also possible that the two piston rods and the two pistons do not have the same diameter. In this case, the order of entry and exit of the piston rods can be influenced or defined by small differences, such as in the piston rod diameter.

In an advantageous embodiment, a gas may be provided as the working fluid in the piston-cylinder unit, in particular in the working spaces of the first cylinder and the second cylinder. In this advantageous embodiment, the first cylinder together with the first piston arrangement forms a first gas spring and the second cylinder together with the second piston arrangement forms a second gas spring. Gas springs are relatively cheap and easy to manufacture and equally provide a very suitable means for use as an adjusting element for example Furniture but also for tailgates in automobiles, etc.

In an alternative advantageous embodiment, a gas and a hydraulic oil may be provided as working fluids in the piston-cylinder unit. Through the use of hydraulic oil, the diameter or the width of both cylinders and thus the piston-cylinder unit can be reduced by the gas springs are replaced by single-acting hydraulic cylinders.

According to a second aspect, the invention is achieved by a telescopic column, in particular for a seat-upright furniture, comprising a lower telescopic tube, a central telescopic tube which is displaceable relative to the lower telescopic tube and an upper telescopic tube, which relative to the central telescopic tube is displaceable, wherein in the central telescopic tube, a piston-cylinder unit according to the first aspect of the invention is arranged and extending in an extended state of the telescopic column and the piston-cylinder unit, the first piston rod of the first piston assembly in the upper telescopic tube and the second piston rod of the second piston assembly extends in the lower telescopic tube.

By the piston-cylinder unit according to the first aspect of the invention, the maximum achievable stroke of such a telescopic column according to the invention is greater than its retracted length. As a result, the telescopic column according to the invention is suitable for applications in which a relatively large stroke is required, in particular for example as a supporting element and at the same time as an adjusting element for a piece of furniture which is to be used both as a chair and as a standing aid. Other applications, for example, as legs for corresponding tables with large necessary adjustment paths are conceivable.

In a particularly preferred embodiment of the present invention, the central telescopic tube may be displaceable within the lower telescopic tube and the upper telescopic tube may be displaceable within the central telescopic tube. This results in a taper of the telescopic column upwards. This is in an application as a telescopic column of a chair or a standing aid, in particular a seat-upright furniture, common and due to the incoming with a taper upwards better stability than a reduction in the diameter of the telescopic tubes downwards also advantageous. The lowest telescopic tube takes on the largest forces when loaded, which is why it makes sense to arrange the telescopic tube with the largest diameter at the bottom or to arrange the arrangement of the telescopic tubes such that the central telescopic tube is displaceable within the lower telescopic tube and the upper telescopic tube is displaceable within the central telescopic tube.

Furthermore, the telescopic column may further comprise a support member which is connected at the upper end of the upper telescopic tube to the upper telescopic tube and forms a receptacle for the first piston rod, wherein the support member is adapted to a functional part of a piece of furniture, in particular a seat and / or an abutment surface for a user of a sit-stand furniture to be coupled. Such a carrier element may act as a connecting element between the telescopic column and a seat and / or a contact surface for the back or the buttocks of a user and be present for example in the form of a seat carrier. In another application of the telescopic column, for example in tables, the support element can act accordingly as a connecting element between the telescopic column and other components, such as a table top or the like. It should be noted that such a carrier element may preferably be formed as a cone, but also any other shapes are possible.

In an advantageous embodiment, the telescopic column may further comprise a triggering mechanism for triggering the piston-cylinder unit, in particular for actuating the actuating part of the piston-cylinder unit. The triggering mechanism can be arranged, for example, on the carrier element. Furthermore, in this advantageous embodiment, the release mechanism can be provided, for example, in particular as a pressure piece, which can be actuated by a lever to be pressed and / or pulled by a user. The pressure piece can then press on actuation of the actuating part, thereby open the valve in the piston and adjust the piston-cylinder unit. Such a triggering mechanism may be provided for actuating a length adjustment of the telescopic column. If the triggering mechanism is arranged on the carrier element, then it is ergonomically easy for a user to reach. In addition, a user is accustomed to an arrangement of the triggering mechanism on the support element of conventional office chairs and a length adjustment of the telescopic column by the user when used as a supporting element and adjusting element, especially in a seat-upholstered furniture can be done intuitively. It should be noted, however, that also differently arranged and differently implemented release mechanisms, such as an arrangement of the trigger mechanism on the lower piston rod or an actuation of the trigger mechanism by a Push button or another actuator instead of a lever, are conceivable.

Further, when the telescopic column includes a bearing assembly disposed at the lower end of the lower telescopic tube and including a receptacle for the second piston rod, the bearing assembly further comprising at least one thrust bearing, the telescopic column may be relative to the fixed portion rotate the bearing assembly, which may be designed in particular as a base of the telescopic column. This is particularly desirable and advantageous when used as a telescopic column of an office chair, a standing aid or a seat-standing aid. It should be noted, however, that it is also possible to make the telescopic column non-rotatable. Likewise, a limited rotation of the telescopic column is possible by providing stop means.

In a particularly advantageous variant, the telescopic column may further comprise a driver tube which is connected to the piston-cylinder unit and arranged around the second piston rod of the second piston assembly, wherein the driver tube is adapted to a rotation of the piston-cylinder To transfer unit to an upper part of the thrust bearing. By virtue of the driver tube transmitting a rotation of the piston-cylinder unit to an upper part of the axial bearing, the driver tube holds the alignment between the middle part of the telescopic column and the axial bearing. If such a driving tube were not present, the lower and the second piston rod would rotate the thrust bearing and would thus be exposed to transverse forces, which occur for example in a rotation in the use of the telescopic column as a supporting element of a seat-upstand, a chair or a stool can.

• 1 eine perspektivische Ansicht einer Kolben-Zylinder-Einheit in einem eingefahrenen Zustand gemäß einer ersten Ausführungsform der vorliegenden Erfindung.
• 2 eine Schnittansicht der Kolben-Zylinder-Einheit gemäß der ersten Ausführungsform in einem ausgefahrenen Zustand.
• 3 eine Schnittansicht der Kolben-Zylinder-Einheit gemäß der ersten Ausführungsform in einem halb ausgefahrenen Zustand.
• 4 eine Seitenansicht der Kolben-Zylinder-Einheit gemäß der ersten Ausführungsform.
• 5 eine Draufsicht der Kolben-Zylinder-Einheit gemäß der ersten Ausführungsform.
• 6 eine Seitenansicht einer teleskopischen Säule in einem ausgefahrenen Zustand gemäß einer Ausführungsform der vorliegenden Erfindung.
• 7 eine Schnittansicht der teleskopischen Säule in einem ausgefahrenen Zustand und eine Seitenansicht der in der teleskopischen Säule eingebauten Kolben-Zylinder-Einheit gemäß der ersten Ausführungsform in einem ausgefahrenen Zustand.
• 8 eine Schnittansicht der teleskopischen Säule in einem eingefahrenen Zustand und eine Seitenansicht der in der teleskopischen Säule eingebauten Kolben-Zylinder-Einheit gemäß der ersten Ausführungsform in einem eingefahrenen Zustand.
• 9 eine Schnittansicht eines unteren Teils der teleskopischen Säule in einem ausgefahrenen Zustand und eine Seitenansicht eines unteren Teils der in der teleskopischen Säule eingebauten Kolben-Zylinder-Einheit gemäß der ersten Ausführungsform in einem ausgefahrenen Zustand.
• 10 eine schematische Darstellung einer Kolben-Zylinder-Einheit gemäß einer zweiten Ausführungsform der vorliegenden Erfindung.

The invention will be explained in more detail below with reference to preferred embodiments with reference to the accompanying drawings. In detail show:

• 1 a perspective view of a piston-cylinder unit in a retracted state according to a first embodiment of the present invention.
• 2 a sectional view of the piston-cylinder unit according to the first embodiment in an extended state.
• 3 a sectional view of the piston-cylinder unit according to the first embodiment in a half-extended state.
• 4 a side view of the piston-cylinder unit according to the first embodiment.
• 5 a plan view of the piston-cylinder unit according to the first embodiment.
• 6 a side view of a telescopic column in an extended state according to an embodiment of the present invention.
• 7 a sectional view of the telescopic column in an extended state and a side view of the built-in telescopic column piston-cylinder unit according to the first embodiment in an extended state.
• 8th a sectional view of the telescopic column in a retracted state and a side view of the built-in telescopic column piston-cylinder unit according to the first embodiment in a retracted state.
• 9 a sectional view of a lower part of the telescopic column in an extended state and a side view of a lower part of the built-in telescopic column piston-cylinder unit according to the first embodiment in an extended state.
• 10 a schematic representation of a piston-cylinder unit according to a second embodiment of the present invention.

With reference to the 1 to 5 becomes a piston-cylinder unit 10 according to a first embodiment of the present invention. The piston-cylinder unit 10 includes a first cylinder 12 , one in the first cylinder 12 used first piston assembly 14 with a first piston rod 16 and a first piston 18 , a second cylinder 22 and one in the second cylinder 22 used second piston assembly 24 with a second piston rod 26 and a second piston 28 , The first cylinder 12 is substantially parallel to the second cylinder 22 aligned and the first piston rod 16 is substantially parallel to the second piston rod 26 aligned. The first piston rod 16 passes through the first cylinder 12 at a first end face S1-1 and the second piston rod 26 passes through the second cylinder 22 at one of the first end face S1-1 of the first cylinder 12 opposite second end face S2-2 of the second cylinder 22 , The first piston 18 divides an interior of the first cylinder 12 in a first workroom A1-1 and a second workspace A2-1 , The first workroom A1-1 is on one side of the first face S1-1 arranged and the second working space A2-1 is on one side of one of the first face S1-1 opposite second end face S2-1 of the first cylinder 12 arranged. The second piston 28 divides an interior of the second cylinder 22 in a first workroom A1-2 and a second workspace A2-2 , The second workroom A1-2 of the second cylinder 22 is on one side of the second face S2-2 of the second cylinder 22 arranged and the first work space A1-2 of the second cylinder 22 is on one side of one of the second end face S2-2 of the second cylinder 22 opposite first end face S1-2 of the second cylinder 22 arranged. The first piston 18 has a valve or a throttle or nozzle bore. The valve or the throttle or nozzle bore connects in an open state, the first working space A1-1 and the second workspace A2-1 of the first cylinder 12 with each other and interrupts the connection between the first working space in a closed state A1-1 and the second workspace A2-1 of the first cylinder 12 , The second piston 28 has no valve and no bore and accordingly, the first working space A1-2 and the second workspace A2-2 of the second cylinder 22 within the second cylinder 22 not directly connected. The first cylinder 12 and the second cylinder 22 can also be present as cylinder cavities in a common housing.

It should be noted that in an alternative embodiment, the second piston 28 instead of the first piston 18 a valve or a throttle or nozzle bore may have and according to the first working space A1-2 and the second working space A2-2 of the second cylinder 22 can be connected to each other and the first work space A1-1 as well as the second working space A2-1 of the first cylinder 12 within the same can not be directly connected.

The piston-cylinder unit 10 is arranged such that a fluid exchange between the first working space A1-1 of the first cylinder 12 and the second workspace A2-2 of the second cylinder 22 is possible and / or a fluid exchange between the first working space A1-2 of the second cylinder 22 and the second workspace A2-1 of the first cylinder 12 is possible.

Because of the first piston 18 the piston-cylinder unit 10 a valve and the second piston 28 the piston-cylinder unit 10 has no valve, a fluid exchange with a working space A1-1 . A2-1 . A1-2 . A2-2 the other cylinder 12 . 22 however, the two oppositely directed piston assemblies act 14 . 24 (First and second piston assembly), which together with the respective associated cylinders 12 . 22 (first and second cylinders) hereinafter also as gas springs due to the use of gas as the working fluid in the first embodiment 12 . 22 (First and second gas spring) are referred to as a single piston assembly or gas spring, but with a larger stroke. That means the two gas springs 12 . 22 essentially go in and out at the same time.

A maximum achievable stroke of the piston-cylinder unit 10 is larger than its retracted length. As a result, the piston-cylinder unit according to the invention is suitable 10 for many applications in which a relatively compact adjustment is required with a relation to the retracted length very large stroke, in particular, for example, as an adjustment for a seat-upright furniture.

In the first embodiment, the first working space A1-1 of the first cylinder 12 via at least one first connection channel 20 for example in the form of a connecting pipe or a connecting hose, in particular a high-pressure hose, with the second working space A2-2 of the second cylinder 22 be connected and / or the first workspace A1-2 of the second cylinder 22 can via at least one second connection channel 30 for example in the form of a connecting pipe or a connecting hose, in particular a high-pressure hose, with the second working space A2-1 of the first cylinder 12 be connected. That is, the fluid exchange between work spaces described above A1-1 and A2-2 as well as the workrooms A2-1 and A1-2 can advantageously by means of these connection channels 20 . 30 occur. The term "connecting channel" is to be understood here as meaning that a fluid exchange is made possible by the connecting channel or the connecting channels. That is, the term "communicating channel" is not to be understood as limiting to components such as pipes or hoses, but rather implies any "channel-like" clearance interconnecting the respective work spaces. The connection channels 20 . 30 can therefore also be present as channel systems or the like, as set forth in the introduction, for example, within a common housing.

The first piston 18 which has the valve in the first embodiment may include an operating part 17 include, which opens the valve when it is actuated and closes the valve when it is not operated. Will the operating part 17 So actuated by a user, in particular pressed, is a fluid exchange between all workspaces A1-1 . A2-1 . A1-2 . A2-2 possible and the piston-cylinder unit 10 can enter and exit. Will the operating part 17 not actuated is the piston-cylinder unit 10 springy blocked.

A maximum stroke of the piston-cylinder unit 10 may be greater than a length of the retracted piston-cylinder unit 10 , The maximum stroke of the piston-cylinder unit 10 can essentially a double length of retracted piston-cylinder unit 10 which is about 440 mm in the first embodiment. This relatively large stroke or adjustment is very favorable for use as an adjustment for a seat-upholstered furniture.

In the first embodiment, further, the first piston rod 16 the first piston assembly 14 have substantially the same diameter as the second piston rod 26 the second piston assembly 14 , Likewise, the first piston 18 the first piston assembly 14 have substantially the same diameter as the second piston 28 the second piston assembly 24 , Assign both piston rods 16 . 26 and both pistons 18 . 28 essentially the same diameter, so produce both piston arrangements 14 . 24 essentially the same ejection and locking forces and both piston rods 16 . 26 can retract and extend substantially simultaneously and at substantially the same rate when the valve of the first piston 18 is open. If the valve is closed, there is no pushing force. It is not exactly defined which gas spring 12 . 22 first goes out. By small differences, such as in the piston rod diameter, the sequence can be influenced or defined during extension and retraction.

In the first embodiment, a gas may be used as the working fluid in the work spaces A1-1 . A2-1 . A1-2 . A2-2 of the first cylinder 12 and the second cylinder 22 the piston-cylinder unit 10 be provided. As mentioned above, then forms the first cylinder 12 together with the first piston assembly 14 a first gas spring 12 and the second cylinder 22 forms together with the second piston assembly 24 a second gas spring 22 ,

With reference to the 6 to 9 becomes a telescopic column 50 according to an embodiment of the present invention, in which the piston-cylinder unit 10 is mounted. The telescopic column 50 includes a lower telescopic tube 52 , a middle telescopic tube 54 and an upper telescopic tube 56 , The middle telescopic tube 54 is relative to the lower telescopic tube 52 but especially not necessarily inside the lower telescopic tube 52 , movable and the upper telescopic tube 56 is relative to the middle telescopic tube 54 but especially not necessarily within the central telescopic tube 54 , movable. In the middle telescopic tube 54 is the piston-cylinder unit 10 arranged according to the first embodiment.

It should be noted that as an alternative to the piston-cylinder unit 10 according to the first embodiment also the below with reference to 10 described piston-cylinder unit 100 according to a second embodiment of the invention in the telescopic column 50 can be arranged.

Furthermore, the telescopic column 50 a carrier element 58 comprising, which at the upper end of the upper telescopic tube 56 with the upper telescopic tube 56 can be connected and a receptacle for the first piston rod 16 can form. The carrier element 58 may be coupled in the preferred embodiment with a seat and / or an abutment surface for the back or the buttocks of a user of a seat-upright furniture and as a connecting element between the telescopic column 50 and a seat and / or abutment surface for the back or buttocks of a user. In other applications of the telescopic column, such as tables, the support element 58 be coupled accordingly with a table top or the like. Preferably, the carrier element 58 be designed as a cone, but other shapes are possible. At the telescopic column 50 , in particular for example on the carrier element 58 , can be a trigger mechanism 60 for triggering the piston-cylinder unit 10 , in particular for actuating the actuating part 17 the piston-cylinder unit 10 be arranged. The trigger mechanism 60 can be provided in this advantageous embodiment, for example, in particular as a pressure piece, which can be actuated by a user to be pressed and / or pulled lever. The pressure piece can then upon actuation of the actuating part 17 Press, thereby the valve in the first piston 18 open and the piston-cylinder unit 10 adjust. Such as for example on the carrier element 58 arranged trigger mechanism can be used to actuate a length adjustment of the telescopic column 50 be provided. Is the trigger mechanism 60 on the carrier element 58 arranged, it is ergonomically easy to reach for a user. In addition, a user is an arrangement of the triggering mechanism 60 on the carrier element 58 used to conventional office chairs and a length adjustment of the telescopic column 50 by the user in an application as a supporting element and adjustment, especially in a seat-upright furniture can be done intuitively.

The telescopic column 50 may preferably be formed such that the gas springs 12 . 22 upon rotation of the telescopic column 50 when used for a rotatable piece of furniture, such as a seat-upright furniture, are not burdened with lateral forces. This can be the first gas spring 12 , their pistons 18 having the valve, be attached only at their ends. The fasteners can be designed so that small inclinations can be compensated and no torque or shear forces on the gas spring 12 Act. The cylinder 22 the downwardly directed second gas spring 22 with the piston 28 without valve or bore can by means of a guide 68 , in which also the lower end of the first gas spring 12 can be fixed, fixed to the middle telescopic tube 54 be connected.

To exclude a load with shear forces, the second piston rod can 26 on a thrust bearing 66 or in particular an axial ball bearing, in which the balls roll on disks, a bearing assembly 62 support. The bearing arrangement 62 may preferably be at the lower end of the lower telescopic tube 52 be provided and a recording 64 for the second piston rod 26 include. The fixed part of the bearing assembly 62 can rotate with the lower telescopic tube 52 be connected, the recording 64 can in the rotating part of the bearing assembly 62 be provided.

Because the second gas spring 22 and with it the second piston rod 26 can be arranged eccentrically to the axis of rotation, can around the second piston rod 26 preferably a driver tube around 70 be provided. This driver tube 70 may be a rotation of the piston-cylinder unit 10 on an upper rotating part of the thrust bearing 66 transferred and thus the alignment between the middle telescopic tube 54 and the bearing assembly 62 hold. Would this driver tube 70 not provided, would be the second gas spring 22 or the second piston rod 26 the thrust bearing 66 turn and would be exposed to lateral forces. To shear forces on the gas springs 12 . 22 further exclude, may additionally a rod 72 be provided with the guide 68 may be connected and in a longitudinal groove, not shown in the driver tube 70 can be guided. As a result, the stability of the entire arrangement with respect to momentary action and lateral forces on the gas springs 12 . 22 be further improved.

10 shows a schematic representation of a piston-cylinder unit 100 according to a second embodiment of the present invention.

In this alternative advantageous embodiment, a gas and a hydraulic oil may be used as working fluids in the piston-cylinder unit 100 be provided. Through the use of hydraulic oil can the diameter of the piston-cylinder unit 100 and thus also the telescopic column 50 be reduced, in which the piston-cylinder unit 100 alternatively to the piston-cylinder unit 10 The first embodiment can be installed. The gas springs of the first embodiment can be replaced by single acting hydraulic cylinders. These hydraulic cylinders 112 . 122 are rigid blocking. If a suspension is desired, as in the 10 illustrated embodiment gas with separating piston 118 . 128 in the cylinders 112 . 122 generate a hub-independent suspension. The seals 138 . 148 to the piston 118 . 128 are more heavily loaded than the seals 136 . 146 on the piston rods 116 . 126 , The seals 136 . 146 on the piston rods 116 . 126 are not exposed to abusive forces, but only seal against the filling pressure. A leak on these seals 136 . 146 however leads to oil loss.

When the telescopic column 50 with a piston-cylinder unit 100 equipped according to the second embodiment and is operated upside down, can gas in the cylinder 112 . 122 reach. If an actuation in the correct position, the cylinders are emptied 112 . 122 again.

Claims (15)

A piston-cylinder unit (10; 100) comprising: a first cylinder (12; 112) having a first cylinder longitudinal axis, a first piston assembly (14; 114) inserted into the first cylinder (12; 112) having a first piston rod (16; 116) penetrating the first cylinder (12; 112) at a first end face (S1-1; SF1-1) and a first piston (18; 118) defining an interior of the first cylinder (12; 112) in FIG a first workspace (A1-1; AR1-1) and a second workspace (A2-1; AR2-1), the first workspace (A1-1; AR1-1) being located on one side of the first endface (S1-1 SF1-1) and the second working space (A2-1; AR2-1) is disposed on one side of a second end face (S2-1; SF2-1) of the first face opposite to the first end face (S1-1; SF1-1) Cylinder (12; 112) is arranged, a second cylinder (22; 122) having a substantially parallel to the first cylinder longitudinal axis aligned second cylinder longitudinal axis and in the second Zy linder (22; 122) having a second piston rod (26; 126) which engages the second cylinder (22; 122) on one of the first end face (S1-1; SF1-1) of the first cylinder (12; A second piston (28, 128) penetrating an interior of the second cylinder (22, 122) into a first working space (A1 -2; AR1-2) and a second working space (A2-2; AR2-2), the second working space (A1-2; AR1-2) of the second cylinder (22; 122) being located on one side of the second end face (A2; S2-2; SF2-2) of the second cylinder (22; 122), and the first working space (A1-2; AR1-2) of the second cylinder (22; 122) is located on a side of one of the second end faces (S2-2 SF2-2) of the second cylinder (22; 122) is disposed opposite to the first end face (S1-2; SF1-2) of the second cylinder (22; 122), characterized in that the first piston (18; 118) or the second piston (28; 128) has a valve which is set up in such a way that in an opened state the first working space (A1-1, A1-2; 1, AR1-2) and the second working space (A2-1, A2-2, AR2-1, AR2-2) of the respective cylinder (12, 22, 112, 122), the piston-cylinder unit ( 10, 100) is arranged such that a fluid exchange between the first working space (A1-1; AR1-1) of the first cylinder (12; 112) and the second working space (A2-2; AR2-2) of the second cylinder (22 122) and / or a fluid exchange between the first working space (A1-2; AR1-2) of the second cylinder (22; 122) and the second working space (A2-1; AR2-1) of the first cylinder (12; 112) is enabled. Piston-cylinder unit (10; 100) after Claim 1 characterized in that the first working space (A1-1; AR1-1) of the first cylinder (12; 112) communicates with the second working space (A2-2; AR2-2) of the second one via at least one first connecting channel (20; 120) Cylinder (22; 122) is connected and / or the first working space (A1-2, AR1-2) of the second cylinder (22; 122) via at least one second connecting channel (30; 130) with the second working space (A2-1; AR2-1) of the first cylinder (12; 112). Piston-cylinder unit (10; 100) after Claim 1 or Claim 2 characterized in that the piston (18, 28, 118, 128) having the valve comprises an actuating part (17) adapted to open the valve when actuated and to close the valve when he is not pressed. Piston-cylinder unit (10) according to one of the preceding claims, characterized in that a maximum stroke of the piston-cylinder unit (10; 100) is greater than a length of the retracted piston-cylinder unit (10; 100), Preferably, that the maximum stroke of the piston-cylinder unit (10, 100) is substantially twice the length of the retracted piston-cylinder unit (10, 100). Piston-cylinder unit (10; 100) according to one of the preceding claims, characterized in that a maximum stroke of the piston-cylinder unit (10; 100) is at least 300 mm, preferably about 440 mm. Piston-cylinder unit (10; 100) according to one of the preceding claims, characterized in that the first piston rod (16; 116) of the first piston assembly (14; 114) has substantially the same diameter as the second piston rod (26; ) of the second piston assembly (24; 124). Piston-cylinder unit (10; 100) according to one of the preceding claims, characterized in that the first piston (18; 118) of the first piston assembly (14; 114) has substantially the same diameter as the second piston (28; ) of the second piston assembly (24; 124). Piston-cylinder unit (10) according to any one of the preceding claims, characterized in that a gas as the working fluid in the piston-cylinder unit (10), in particular in the work spaces (A1-1, A2-1, A1-2, A2-2) of the first cylinder (12) and the second cylinder (22) is provided. Piston-cylinder unit (100) according to one of Claims 1 to 7 , characterized in that a gas and a hydraulic oil are provided as working fluids in the piston-cylinder unit (100). Telescopic column (50), in particular for a seat-upright furniture comprising a lower telescopic tube (52), a central telescopic tube (54) which is displaceable relative to the lower telescopic tube (52) and an upper telescopic tube (56) relative to the central telescopic tube (54) is displaceable, characterized in that in the central telescopic tube (54) a piston-cylinder unit (10; 100) is arranged according to one of the preceding claims and that in an extended state of the telescopic column (50) and the piston-cylinder unit (10; 100) extends the first piston rod (16; 116) of the first piston assembly (14; 114) in the upper telescopic tube (56) and the second piston rod (26; 126) of the second Piston assembly (24, 124) in the lower telescopic tube (52) extends. Telescopic column (50) after Claim 10 , characterized in that the central telescopic tube (54) within the lower telescopic tube (52) is displaceable and the upper telescopic tube (56) within the central telescopic tube (54) is displaceable. Telescopic column (50) after Claim 10 or Claim 11 further comprising a support member (58) connected to the upper telescopic tube (56) at the upper end of the upper telescoping tube (56) and forming a receptacle for the first piston rod (16; 116), the support member (58) thereon is arranged to be coupled to a functional part of a piece of furniture, in particular a seat and / or a contact surface for a user of a seat-upright furniture. Telescopic column (50) after Claim 12 further comprising a triggering mechanism (60) for actuating the piston-cylinder unit (10; 100), in particular for actuating the actuating part (17) of the piston-cylinder unit (10). Telescopic column (50) according to one of Claims 10 to 13 further comprising a bearing assembly (62) disposed at the lower end of the lower telescoping tube (52) and including a receptacle (64) for the second piston rod (26; 126), the bearing assembly (62) further comprising at least one thrust bearing (62). 66). Telescopic column (50) after Claim 14 further comprising a drive tube (70) connected to the piston-cylinder unit (10; 100) and disposed about the second piston rod (26; 126) of the second piston assembly (24; 124), the drive tube (70). 70) is adapted to transmit rotation of the piston-cylinder unit (10, 100) to an upper part of the thrust bearing (66).

Images