Lift column for a piece of furniture

Abstract

This application relates to a lifting column for a piece of furniture, particularly a table. The lifting column includes a first element and a second element. The second element is introduced into the first element in at least some way. The first element has a spindle extending along the longitudinal axis of the first element and projecting into the second element in at least some way. The second element has a rotor rotatably mounted therein, and the rotor has at least one rolling element that moves in or on a threaded helix of the spindle. Rotation of the rotor relative to the spindle causes linear movement of the second element relative to the first element. The second element also has a stop that blocks rotation of the rotor relative to the spindle in a first state and releases rotation of the rotor relative to the spindle in a second state. At least one leg spring is clamped between the rotor and a fastening element fastened to the second element, and thus the leg spring subjectes the rotor to prestress.

Description

Technical Field

[0001] This invention relates to a lifting column for a piece of furniture, particularly a table, which provides weight compensation for the furniture. The invention also relates to a piece of furniture, particularly a table, having at least one lifting column with weight compensation for the furniture. Background Technology

[0002] Prior art discloses various lifting columns and / or height-adjustable legs for assembled furniture, particularly for tables. The length of the lifting column and / or legs can be adjusted by a motor or manually. Especially in the case of manual adjustment, it is advantageous if the lifting column and / or height-adjustable legs have a device that can compensate for the weight of the assembled furniture, particularly the weight of the tabletop.

[0003] US 7,658,359 discloses, for example, a device for adjusting the height of a table. The table leg includes a first outer column element and a second inner column element, a weight compensation device, a stopping device, and rollers arranged on the inner column element and interacting with raceways in the outer column element. The weight compensation device particularly includes a spring, a worm gear for compensating for a variable spring force, and a cable that interacts with the worm gear and is fastened to the inside of the outer column element. The prestress of the compression spring acting on the cable mounting can be set by means of a drum actuated by a knob. Summary of the Invention

[0004] The purpose of this invention is to create a lifting column that belongs to the technical field mentioned in the introduction and has a simple construction and weight compensation.

[0005] This objective is achieved by means of the features defined in claim 1. According to the invention, the lifting column includes a first element and a second element. The second element is at least partially incorporated into the first element. The first element includes a spindle extending along the longitudinal axis of the first element and at least partially projecting into the second element. The second element includes a rotor rotatably mounted within the second element and including at least one rolling element that moves in or on a threaded helix of the spindle. Rotation of the rotor relative to the spindle results in linear movement of the second element relative to the first element. The second element also includes a stop that blocks rotation of the rotor relative to the spindle in a first state and releases rotation of the rotor relative to the spindle in a second state. At least one leg spring is clamped between the rotor and a fastening element fixed to the second element, the leg spring subjecting the rotor to prestress.

[0006] The prestress of at least one leg spring can at least partially compensate for the weight of a piece of furniture connected to the lifting column. Furthermore, using at least one leg spring simplifies the construction of the lifting column. Moreover, the lifting column according to the invention requires very little maintenance.

[0007] In this application, the lifting column is understood as a device that can be positioned on a lower surface, particularly on the floor, and can be connected to a piece of furniture, the length of which can be changed in order to set the height of the furniture.

[0008] The lifting column according to the invention is particularly suitable for tables. In this case, the lifting column is preferably connected to the tabletop. The table preferably includes one, two, or even four lifting columns according to the invention.

[0009] The first and second elements are constructed as hollow bodies, with both elements having the same cross-sectional shape. To allow the second element to be inserted into the first element, the second element has a slightly smaller cross-sectional dimension. The cross-sectional dimensions of the first and second elements are preferably chosen such that a gap of a few millimeters, but particularly less than 1 cm, exists between the elements when the second element is inserted into the first element. The second element is inserted concentrically into the first element, that is, the longitudinal axis of the first element coincides with the longitudinal axis of the second element.

[0010] The first and second elements are preferably circular, rectangular, or polygonal in cross-section. The first and second elements are preferably made of metal or metal alloy, particularly stainless steel or aluminum. Both elements preferably have an elongated structure, that is, their length is significantly greater than their cross-section. The first and second elements preferably each have a length of at least 35 cm, particularly at least 45 cm. The maximum dimension of the two elements in cross-section is preferably 3 cm, more preferably 5 cm.

[0011] The first element preferably has a closed surface area at its first end, by means of which the first element can be positioned on a lower surface, particularly a floor. The first element opens at a second end positioned opposite the first end, so that the first end of the second element can be inserted into the second end of the first element. At the second end of the second element, positioned opposite the first end, the second element preferably has means for fastening the second element to a piece of furniture. These means are preferably configured in the form of holes or slots for screws or bolts.

[0012] The length of the lifting column can be adjusted by moving the second element into and / or out of the first element. This length adjustment allows the height of a piece of furniture connected to the lifting column to be set. Therefore, depending on the length setting of the lifting column, the second element is inserted into the first element at its longer or shorter portion.

[0013] The mandrel is preferably centrally located within the first element and extends from a first end of the first element to a second end. Thus, the mandrel extends along the longitudinal axis of the first element. The mandrel may extend along the entire length of the first element, that is, from its first end to its second end. However, the mandrel preferably extends only along a portion of the length of the first element.

[0014] The mandrel preferably has a high-helix thread. The term "high-helix thread" should be understood in the following application to mean a thread with a pitch (helix height) of at least 10 mm, preferably at least 20 mm. The mandrel preferably has one threaded helix. However, as an alternative, the mandrel may also have more than one threaded helix, particularly two threaded helices.

[0015] The rotor is preferably mounted in the second element such that it can rotate via rolling bearings, and thus the rotor can rotate relative to the second element. The rotor is oriented such that it can rotate about the longitudinal axis of the second element. At least one rolling element of the rotor is preferably arranged at an angle corresponding to the pitch angle of the spindle. The rotor preferably has more than one rolling element, particularly three rolling elements, which in each case are arranged at an angle of 120° relative to each other in the circumferential direction of the rotor.

[0016] The rotation of the rotor means that, due to the movement of at least one rolling element in or on the threaded helix of the spindle, the rotor will be linearly displaced relative to the spindle. Since the rotor is rotatably mounted on the second element, the displacement of the rotor relative to the spindle also results in a linear displacement of the second element relative to the first element.

[0017] When the stop device blocks the rotation of the rotor, it prevents unintended length adjustments of the lifting column. If the lifting column is secured to a piece of furniture, the stop device remains in the first state and only transitions to the second state when the height of the furniture needs to be adjusted. To switch between (and return to) the first and second states, the stop device preferably has a human-actuable actuation element, particularly a lever or button.

[0018] The length adjustment of the lifting column according to the invention is preferably performed manually. This means that the length is adjusted by pulling the second element out of the first element or by pushing it into the first element. If a piece of furniture is connected to the lifting column, pulling the furniture upward or pushing it downward can result in the length adjustment of the lifting column, and ultimately the height adjustment of the furniture. In the first state, the stop device blocks the rotation of the rotor, and therefore also blocks the length adjustment of the lifting column and the height adjustment of the furniture connected to the lifting column.

[0019] However, as an alternative, the rotor can be rotated by an electric or electromechanical drive, which allows for automatic length adjustment of the lifting column and automatic height adjustment of a piece of furniture connected to the lifting column.

[0020] Preferably, the fastening element is fixed to the second element, meaning that the fastening element cannot rotate about the longitudinal axis of the second element. At least one leg of the support spring has its first leg connected to or abutting the fastening element, while the second leg is rotatably fixed to the rotor.

[0021] The support leg spring has two legs, with multiple coils of the spring located between the two legs. The at least one support leg spring is preferably arranged inside the second element such that the longitudinal axis of the support leg spring coincides with the longitudinal axis of the second element.

[0022] The prestress of the support leg springs subject the rotor to torque. If the rotor's rotation has been released by the stop device, this torque causes the rotor to rotate in one direction. Here, the support leg springs are arranged such that the prestress subject the rotor to torque, which causes the second element to move out of the first element, that is, causes the length of the lifting column to increase. Here, the second element is subjected to a force oriented in the corresponding direction. When the lifting column is used as intended, the first element stands on the lower surface, particularly the floor, with the longitudinal axes of the first element and the second element positioned perpendicular to the lower surface. Therefore, the longitudinal axes of the first and second elements are oriented substantially parallel to the direction of gravity. Therefore, the force acting on the second element is substantially vertically upward. Thus, this force counteracts the weight of a piece of furniture connected to the lifting column. This makes it possible to at least partially compensate for the weight of said piece of furniture, which makes it particularly easier to increase the length of the lifting column and the height of said piece of furniture. Therefore, a proper setting of the prestress of the support leg springs can also fully compensate for the weight of a piece of furniture connected to the lifting column. In this situation, even when the stop device is in the second state, the piece of furniture cannot be height adjusted without any external force, because the weight and the force acting on the second element cancel each other out.

[0023] The at least one rolling element is preferably configured as a ball, cylindrical roller, tapered roller, or tubular roller.

[0024] If the at least one rolling element is configured as a ball or a cylindrical roller, the at least one rolling element moves in or engages in a threaded helix. If the at least one rolling element is configured as a tapered roller or a cylindrical roller, the at least one rolling element preferably moves on a threaded helix of a spindle.

[0025] In order to set the prestress of at least one outrigger spring, the fastening element can preferably move in an arc around the longitudinal axis of the outrigger spring.

[0026] The circular movement of the fastening element allows for the setting of a prestress in the support leg spring corresponding to the spring force. Here, the fastening element has a device capable of preventing rotation of the fastening element. This allows the set prestress to be maintained. This device particularly has a lever or handle that can be operated manually. Furthermore, the second element preferably has an adjustment device by which the fastening element can be moved in a circular motion about the longitudinal axis of the support leg spring.

[0027] The fastening element is preferably arranged on a worm gear, which can be rotated by means of a worm connected to the second element in a rotationally fixed manner.

[0028] This achieves a particularly simple embodiment of the fastening element, which can move in a circular motion around the longitudinal axis of the support leg spring. Furthermore, the inherent self-locking action in the worm gear eliminates the need for additional devices to prevent the fastening element from moving in a circular motion around the longitudinal axis of the support leg spring.

[0029] The first element and the second element preferably have a circular cross-section, wherein the second element has a smaller diameter than the first element.

[0030] The second element is preferably guided in a linearly movable manner within the first element by at least one linear guide. The linear guide prevents the second element from rotating within the first element. The second element is preferably guided within the first element by more than one linear guide, particularly by two, three, or four linear guides. The linear guide can be configured, for example, as a pin moving in a groove or as a roller guide.

[0031] The second element preferably has at least one rolling bearing, wherein the outer ring of the rolling bearing is introduced into a groove in the first element to form at least one linear guide. This allows for the provision of a linear guide with very low resistance, and it also saves space in a direct manner.

[0032] The rolling bearings used are preferably ball bearings. However, cylindrical roller bearings or needle roller bearings can also be used as alternatives. The second element preferably has a plurality of circumferentially distributed rolling bearings, which are introduced into a corresponding number of grooves in the first element.

[0033] In a preferred embodiment, the first element has three rolling bearings, which in each case are arranged at an angle of 120° relative to each other about the longitudinal axis of the second element.

[0034] In another preferred embodiment, two of the three rolling bearings are arranged at an angle of 90° relative to each other, wherein each of these two rolling bearings is arranged at an angle of 135° relative to the third rolling bearing about the longitudinal axis of the second element. In this embodiment, the first element preferably has eight slots, which in each case are arranged at an angle of 45° relative to each other about the longitudinal axis of the first element. This allows the second element to be introduced into the first element at eight different angular positions.

[0035] The rotor is preferably connected to a hollow shaft that extends coaxially relative to the second element to a second end of the second element, which is not introduced into the first element, wherein the hollow shaft has a toothed structure in the region of the second end of the second element.

[0036] In the first state, the stop device is preferably engaged in the toothed structure by a rack fastened to the second element or by a gear connected to the second element in a rotationally fixed manner. This means that the rotating shaft, and therefore the rotor connected thereto, cannot rotate. In the second state, the rotation of the hollow shaft, and therefore the rotor, can be released by lifting, pushing, or pivoting away from the toothed structure via the rack or gear.

[0037] Furthermore, the toothed structure can be used to synchronize the length adjustment of multiple lifting columns, since the lifting columns are connected by means of at least one shaft, which uses gears or helical gears to engage in the toothed structure of the respective lifting column in each case.

[0038] The threaded helix of the mandrel preferably has a variable pitch. This allows for compensation of the leg spring force, which varies depending on the depth to which the second element is introduced into the first element.

[0039] The movement of the second element relative to the first element causes the rotor to rotate about the spindle. This means that, depending on the position of the second element relative to the first element, the helical spring experiences a greater or lesser degree of stress, resulting in a change in the spring force experienced by the rotor, or the torque thereby. Nevertheless, by using a corresponding change in the pitch of the threaded helix, the force applied to the rotor by the leg spring and thus to the second element can be kept constant. In regions where the leg spring experiences less stress and therefore exerts a smaller spring force, the pitch of the threaded helix is ​​smaller than the pitch in regions where the leg spring has a higher stress level and therefore a higher spring force.

[0040] The at least one rolling element is preferably a cylindrical roller, tapered roller, or tubular roller, configured as a rolling bearing in which the outer ring forms a cylindrical roller, tapered roller, or tubular roller and moves in or on a threaded helix of a spindle. This arrangement allows for a simple, low-maintenance construction of at least one rolling element, which also has very low rolling resistance.

[0041] In this embodiment, the outer ring of the rolling bearing thus forms a rolling element that moves within or on the threaded helix of the spindle. Therefore, the rolling element, designed as a rolling bearing, can be connected to the rotor via its inner ring. The shape of the outer ring corresponds to the shape of the rolling element.

[0042] The rolling bearings used are preferably ball bearings. However, cylindrical roller bearings or needle roller bearings can also be used as alternatives. The outer ring of the rolling bearing preferably has a convex surface extending around it, and this convex surface is complementary to the profile of the threaded helix. This results in at least one rolling element engaging in the threaded helix of the spindle with particularly good effect.

[0043] Multiple outrigger springs, particularly two outrigger springs, are preferably clamped between the rotor and the fastening element in a parallel configuration. This means that all of these multiple outrigger springs have one outrigger fastened to the rotor, while the other outrigger rests against or is connected to the fastening element.

[0044] This arrangement can increase the prestress exerted on the rotor by the support leg springs.

[0045] The present invention also relates to a piece of furniture having at least one of the aforementioned lifting columns, and further having at least one furniture element fastened to said at least one lifting column. The piece of furniture is preferably a table, in which case the furniture element fastened to said at least one lifting column is a tabletop.

[0046] The piece of furniture preferably has more than one lifting column, particularly two or four lifting columns. For example, the piece of furniture may be a height-adjustable table with two lifting columns secured to a rectangular tabletop.

[0047] The shaft is preferably mounted on a furniture element and has a helical gear that engages in the toothed structure of the hollow shaft of at least one lifting column.

[0048] This shaft synchronizes the rotation of the rotors of multiple lifting columns fastened to the furniture element. The shaft preferably has helical gears at both ends, and thus the shaft can synchronize the rotation of the rotors of two lifting columns fastened to the furniture element. If more than two lifting columns are fastened to the furniture element, multiple shafts with two helical gears are used accordingly.

[0049] The shaft is preferably mounted on the furniture element by means of a retainer, wherein the retainer has a double-wound spring brake acting on the shaft. Here, the double-wound spring brake serves as a stopping device because it can prevent and release the rotation of the hollow shaft, and thus prevent and release the rotation of the rotor connected to it. Preferably, the retainer has an actuating element, such as a rod, which can release the braking effect exerted on the shaft by the double-wound spring brake.

[0050] The crankshaft is preferably mounted on the furniture element, and the crankshaft can drive the worm gear. This simplifies the height adjustment of at least one furniture element, as this can be achieved by rotating the crankshaft.

[0051] Other advantageous embodiments and combinations of features of the invention can be obtained from the following detailed description and claims, in their entirety. Attached Figure Description

[0052] In the accompanying drawings, which are used for the purpose of explaining exemplary embodiments:

[0053] Figure 1 A cross-sectional view of one embodiment of the lifting column according to the present invention is shown;

[0054] Figure 2 It shows according to Figure 1 A perspective view of the rising column;

[0055] Figure 3 A detailed view of the second end of the second element is shown;

[0056] Figure 4a and Figure 4b A detailed specific view of a second embodiment of a lifting column according to the present invention is shown, the lifting column having rolling elements designed in the form of ball bearings; and

[0057] Figure 5a and Figure 5b A detailed specific view of a third embodiment of a lifting column according to the invention is shown, the lifting column having rolling elements designed in the form of tapered rollers.

[0058] In principle, identical components are given the same reference numerals in the drawings. Detailed Implementation

[0059] Figure 1 A cross-sectional view of an embodiment of a lifting column 1 according to the present invention is shown. The lifting column 1 includes a first element 2 having a surrounding first wall 6 that surrounds an interior space. A second element 3 having a second surrounding wall 7 is at least partially introduced into the first element 2, that is, introduced into the interior space of the first element 2. A first end of the second element 3 is located within the first element 2, while a second end of the second element 3 protrudes from the first element, opposite to the first end.

[0060] In the illustrated embodiment, the two elements 2 and 3 have circular cross-sections, wherein the diameter of the second element 3 is smaller than the diameter of the first element 2. The second element 3 can be linearly displaced within the first element 2. This means that the second element 3 can move linearly within the first element along the longitudinal axis A of the first element. The second element 3 has the same longitudinal axis A as the first element 2.

[0061] The second element 3 is mounted in the first element 2 in a displaceable manner via a linear guide. On the side of the first wall 6 that guides toward the interior space, the linear guide has grooves 19.1, 19.2, in which the corresponding outer rings of rolling bearings 18.1, 18.2, arranged at the first end of the second element 3, move. In the illustrated embodiment, the first element has eight grooves 19.1, 19.2. Figure 1 Only two of them are shown, distributed on the first wall 6 in each case offset from each other by 45° around the longitudinal axis A. The second element 3 also has three rolling bearings 18.1, 18.2. Figure 1 Only two of them are shown in the diagram. The first rolling bearing 18.1 and the second rolling bearing 18.2 are positioned at an angle of 135° relative to each other about the longitudinal axis A, while the third rolling bearing (not visible here) is positioned at an angle of 90° relative to the first rolling bearing 18.1 and the second rolling bearing 18.2 in each case.

[0062] The first element 2 also has a closed surface region 24 at its first end. The first element 2 can be positioned on the floor by means of this closed surface region 24. A mandrel 4 is centrally secured within the first element 2 at this closed surface region 24. The mandrel 4 extends along the longitudinal axis A of the first element 2, but does not extend all the way to the second end of the first element. This means that the mandrel 4 does not protrude from the internal space of the first element 2. The mandrel 4 has a threaded helix 5 with a variable pitch. The pitch of the threaded helix 5 decreases from the first end to the second end of the mandrel 4.

[0063] Rotor 8 is arranged in the region at the first end of second element 3. Rotor 8 is rotatably mounted on second element 3, which allows the rotor to rotate freely about longitudinal axis A, although it cannot be displaced relative to second element 3. Three rolling elements 9.1 are arranged on rotor 8. Figure 1 (Only one is shown), the rolling element is designed in the form of a cylindrical roller and engages in the threaded helix 5 of the spindle 4. The rolling element 9.1 is mounted at an angle relative to the rotor 8, and the rolling element is thus able to engage in the threaded helix 5 in a substantially clearance-free manner. Due to the engagement of the rolling element 9.1 in the threaded helix 5, the rotation of the rotor 8 causes the second element 3 to move linearly relative to the first element 2.

[0064] In the region at the second end, the second element 3 has two fastening elements 15.1 and 15.2. Two leg springs 14.1 and 14.2 are clamped between the fastening elements 15.1 and 15.2 and the rotor 8. The leg springs 14.1 and 14.2 are rotatably fastened to the rotor 8 and also to the corresponding fastening elements 15.1 and 15.2. The leg springs 14.1 and 14.2 prestress the rotor 8. This prestress subjectes the rotor 8 to torque. Here, the leg springs 14.1 and 14.2 are prestressed such that the torque causes the rotor 8 to rotate in the direction that moves the second element 3 out of the first element 2. If the lifting column 1 is standing on the floor, the prestress thus increases the length of the lifting column 1. Thus, the prestress can compensate for the weight of a piece of furniture fastened to the lifting column 1. That is, the prestress is chosen such that it substantially corresponds to the weight of the piece of furniture connected to the lifting column 1. This allows one to set the height of the piece of furniture relatively directly without applying any large force.

[0065] Depending on the position of the rotor 8 along the spindle 4, the prestress exerted by the support springs 14.1 and 14.2 on the rotor 8 varies because the support springs 14.1 and 14.2 rotate more or less from their rest positions as the rotor 8 rotates. To ensure that the prestress exerted by the rotor 8 on the second element 3 remains substantially constant at any position along the length of the rotor 8 along the spindle 4, the spindle 4 has the aforementioned variable thread pitch.

[0066] The worm gear 16 is arranged in the region of the second end of the second element 3 and has fastening elements 15.1 and 15.2 connected thereto. The worm gear 16 can be connected by means of the worm 17 (see...). Figure 3 The fastening elements 15.1 and 15.2 rotate simultaneously, thus changing the prestress of the outrigger springs 14.1 and 14.2.

[0067] The rotor 8 is connected to a hollow shaft 12, which extends along the second end of the second element 3 within the windings of the support springs 14.1 and 14.2. The hollow shaft 12 has a toothed structure 13 in the region of the second end of the second element 3. A helical gear 11 engages in this toothed structure 13. The helical gear 11 and the toothed structure 13 together form a stop device 10, which prevents rotation of the rotor 8 relative to the spindle 4 in a first state and releases that rotation in a second state. In the first state, rotation of the helical gear 11 is prevented, while in the second state, the rotation is released. This can be achieved by providing a suitable mechanism. For example, the helical gear 11 can be connected to a shaft (not shown) that interacts with a double-wound spring brake.

[0068] A fastening element 21 is arranged at the second end of the second element 3, which can be used to fasten the lifting column 1 to a piece of furniture, particularly to a tabletop. In addition, a flange is arranged in the region of the second end of the first element 2.

[0069] Figure 2 It shows according to Figure 1 A perspective view of the lifting column, wherein the first wall 6 and the second wall 7 have been omitted for illustrative purposes. The diagram clearly shows the arrangement of three rolling bearings 18.1, 18.2, and 18.3, which, together with the slots 19.1 and 19.2 of the first element 2, form a linear guide. Also clearly visible is the inclined arrangement of the rolling elements 9.1 and 9.2 of the rotor 8, which are designed in the form of cylindrical rollers and engage in the threaded helix 5 of the spindle 4.

[0070] According to Figure 1 Compared to the cross-sectional view, according to Figure 2 The perspective view shows the worm gear 16 for better performance. The worm 17 is held in a rotatable manner relative to the second element 3 by the retainer 22.

[0071] Figure 3 A perspective detail view of the second end of the second element 3 is shown. It clearly shows the worm 17 engaging with the worm gear 16. The worm 17 has an internal hexagonal actuator 25. The worm 17 can be rotated via a hexagonal key through this actuator 25.

[0072] The helical gear 11 is rotatably mounted in the cover 23 and engages with the toothed structure 13 of the hollow shaft 12. The helical gear 11 has a central hole 26 by means of which the helical gear 11 can be engaged with a shaft (not shown).

[0073] Figure 4a and Figure 4b A detailed view of a second embodiment of the lifting column 1 according to the invention is shown, in which the rolling elements 9.1-9.3 are designed in the form of balls. Figure 4a A perspective view of a spindle 4 with three threaded helices 5.1-5.3 is shown, in which corresponding rolling elements 9.1-9.3, designed in the form of balls, move. The three rolling elements 9.1 to 9.3 are arranged at an angle of 120° relative to each other in each case, which can be seen in this… Figure 4b The cross-sectional view is better represented. The threaded helix of the mandrel 4, 5.1-5.3, has a circular cross-section, so the rolling elements 9.1-9.3, designed in the form of balls, can move within it with the smallest possible clearance.

[0074] Figure 5a and Figure 5b A detailed specific view of a third embodiment of the lifting column 1 according to the invention is shown, in which the rolling elements 9.1-9.3 are designed in the form of tapered rollers. Figure 5a A perspective view of the mandrel 4 with rolling elements 9.1-9.3 is shown, while Figure 5b This is a cross-sectional view. These rolling elements 9.1-9.3 move on threaded helices 5.1-5.3 of the spindle 4, which are located in the form of regions on the surface of the spindle 4. Each rolling element 9.1-9.3, designed as a tapered roller, has a pin 27.1-27.3, through which the rolling element 9.1-9.3 is connected to the rotor 8.

Claims

1. A lifting column for a piece of furniture, comprising a first element and also a second element which is introduced at least partially into the first element, wherein The first element has a spindle which extends along a longitudinal axis of the first element and projects at least in some way into the second element, and wherein the second element has a rotor which is mounted in a rotatable manner in the second element and has at least one rolling body which moves in or on a threaded helix of the spindle, wherein a rotation of the rotor relative to the spindle causes a linear movement of the second element relative to the first element, wherein the second element has a stop device which blocks a rotation of the rotor relative to the spindle in a first state and releases a rotation of the rotor relative to the spindle in a second state, characterized in that at least one leg spring is clamped between the rotor and a fastening element which is fastened on the second element, which leg spring prestresses the rotor.

2. The lift column of claim 1, wherein, The at least one rolling body is configured in the form of a ball, a cylindrical roller, a conical roller or a barrel roller.

3. A lifting column according to any one of claims 1 and 2, characterized in that In order to set the prestress of the at least one leg spring, the fastening element is movable in the form of an arc of a circle about a longitudinal axis of the leg spring.

4. A lifting column according to claim 3, characterised in that The fastening element is arranged on a worm wheel which is rotatable by means of a worm which is connected in a rotationally fixed manner to the second element.

5. A lifting column according to claim 1 or 2, characterised in that The first element and the second element have a circular cross section, wherein the second element has a smaller diameter than the first element.

6. A lifting column according to claim 1 or 2, characterised in that The second element is guided by at least one linear guide in a linearly movable manner within the first element.

7. A lifting column according to claim 6, characterised in that The second element has at least one rolling bearing, wherein an outer ring of the rolling bearing is introduced into a groove of the first element in order to form the at least one linear guide.

8. A lifting column according to claim 1 or 2, characterised in that The rotor is connected to a hollow shaft which extends coaxially relative to the second element to a second end of the second element within the second element, which second end is not introduced into the first element, wherein the hollow shaft has a toothing in the region of the second end of the second element.

9. A lifting column according to claim 1 or 2, characterised in that The threaded helix of the spindle has a variable pitch.

10. A lifting column according to claim 1 or 2, characterised in that The at least one rolling body is a cylindrical roller, a conical roller or a barrel roller which is configured in the form of a rolling bearing, wherein an outer ring of the rolling bearing forms the cylindrical roller, the conical roller or the barrel roller and moves in or on the threaded helix of the spindle.

11. A lifting column according to claim 1 or 2, characterised in that A plurality of leg springs is clamped in a parallel state between the rotor and the fastening element.

12. The lifting column of claim 11, wherein, Two leg springs are clamped in a parallel state between the rotor and the fastening element.

13. A lifting column according to claim 1 or 2, characterised in that The piece of furniture is a table.

14. A piece of furniture having at least one lifting column according to any one of claims 1 to 12 and further having a furniture element on which the second element of the lifting column is fastened.

15. The piece of furniture of claim 14, wherein, The piece of furniture is a table.

16. The piece of furniture of claim 14, wherein The rotor is connected to a hollow shaft which extends coaxially within the second element to a second end of the second element which is not introduced into the first element, wherein the hollow shaft has a toothed structure in the region of the second end of the second element and a second shaft is fitted on the furniture element, the second shaft having a helical gear which engages in the toothed structure of the hollow shaft of the at least one lifting column.

17. The piece of furniture of claim 16, wherein The second shaft is fitted on the furniture element by means of a holder, wherein the holder has a double wrap spring brake which acts on the second shaft.

18. The piece of furniture of claim 16 or 17, wherein, In order to set the prestress of the at least one leg spring, the fastening element is movable in the form of a circular arc about a longitudinal axis of the leg spring and the fastening element is arranged on a worm wheel which is rotatable by means of a worm which is connected in a rotationally fixed manner to the second element, wherein a crankshaft is fitted on the furniture element, the crankshaft being able to drive the worm.

19. The piece of furniture according to any one of claims 14 to 17, characterized in that The furniture element is a table top.

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