HEIGHT-ADJUSTABLE TABLE LEG, TABLE FRAME AND TABLE

Description

Background of the invention

[0001] The invention relates to a height-adjustable table leg with a support device, a threaded spindle, and a bearing flange, via which the threaded spindle is rotatably supported on a base of the support device. The invention further relates to a height-adjustable table frame with two table legs and a height-adjustable table with a table top and a table frame.

[0002] Table legs of the type mentioned above are known from the prior art, for example, from WO 2013 / 159776 A1. Such table legs are used particularly for height-adjustable desks. To prevent damage to the table or the colliding parts in the event of collisions that may occur during height adjustment, it is generally known to use sensors to detect such collisions. According to the aforementioned WO 2013 / 159776 A1, the bearing flange can have a piezo element with a through hole for the spindle to detect forces acting on the spindle.

[0003] EP 1 704 797 B1 discloses a work table with a height-adjustable frame, for whose adjustment at least one electric motor acting on an actuator with a control device is provided. At least one load-bearing part connects the actuator to an adjustment part of a telescopic leg of the frame. The load-bearing part is provided with a strain gauge. The strain gauge controls the control device for the motor depending on the magnitude of a load change in the load-bearing part. The load-bearing part can be designed as a bending beam. A similar table is described in SE 516 479 C2.

[0004] DE 20 2010 015 736 U1 describes a linear drive comprising an electric motor arranged in a housing and having a motor shaft that drives a spindle via a gear mechanism. Attached to the spindle nut is a spindle nut that is fixed against rotation and is operatively connected to an actuating component or is itself designed as an actuating component. The actuating component comprises a clamping protection device with a force sensor that generates force sensor signals to detect obstacles or impediments to the movement of the actuating component and / or the spindle nut. The force sensor is mounted between the motor and the housing in such a way that it can be influenced by the motor. Object of the invention

[0005] It is an object of the invention to provide a precisely operating and structurally simple sensor system for collision detection in height-adjustable tables, which can in particular be easily adapted to existing table legs. Description of the invention

[0006] This object is achieved according to the invention by a table leg having the features specified in claim 1 as well as a table frame according to claim 13 and a table according to claim 15. Advantageous embodiments are specified in the respective subclaims and the description. Table leg according to the invention

[0007] According to the invention, a height-adjustable table leg is provided. In other words, the table leg is variable in length, allowing the height of a table to be adjusted using the table leg. The table leg is generally height-adjustable by a motor, i.e., a motor, in particular an electric motor, can be used to adjust the length.

[0008] The table leg has a support mechanism. The support mechanism serves to attach the table leg to a crossbar of a table frame or to a table top, or the support mechanism serves to attach the table leg to a foot extension or to support the table leg on a floor.

[0009] The receiving device can be designed in the form of a pot or as a substantially flat plate. In any case, the receiving device has a base. When the table leg is in the position of use, the base typically extends horizontally. Furthermore, the receiving device can have a side wall, preferably two opposing side walls, and / or a rear wall. The rear wall can extend between the two side walls and preferably run orthogonally to them.

[0010] The table leg further comprises a threaded spindle and a bearing flange. The threaded spindle is rotatably supported on the base of the support device via the bearing flange. The bearing flange allows the threaded spindle to rotate about its longitudinal axis without changing its translational position relative to the support device. For this purpose, a bearing, preferably a rolling bearing, can be arranged between an outer part of the bearing flange fixed to the base and an inner part of the bearing flange fixed to the threaded spindle. The outer part and / or the inner part can be made up of multiple parts.

[0011] The bearing flange is preferably held in a form-fitting manner on the base of the receiving device. Typically, the bearing flange is inserted into a recess in the base and overlaps one edge of the recess on both the top and bottom sides.

[0012] To create a change in the length of the table leg when the threaded spindle rotates around its longitudinal axis, the threaded spindle can engage a threaded piece. The threaded piece is rotationally fixed to a component of the table leg spaced apart from the receiving device, for example, to a base section of the table leg. When the threaded spindle rotates, the intermeshing threaded sections of the threaded spindle and the threaded piece move the threaded spindle and the threaded piece relative to each other along the longitudinal axis of the threaded spindle.

[0013] The table leg can comprise several interlocking tubular elements. The tubular elements can extend between the receiving device and the base. When the length of the table leg changes, the tubular elements are moved telescopically toward each other, i.e., pushed into each other or pulled apart. A foot extension can be provided on the base, which can extend orthogonally away from the tubular elements.

[0014] A motor, particularly an electric motor, can be provided to rotate the threaded spindle. The motor is preferably mounted on the mounting device. Alternatively, the motor can be mounted, for example, on a cross member of a table frame. The motor can engage directly on the threaded spindle. Alternatively, a gear can be provided between the motor and the threaded spindle.

[0015] According to the invention, the table leg has a sensor arm with a strain gauge. The sensor arm is attached to the support device and rests in contact with the bearing flange. The sensor arm contacts a part of the bearing flange fixed to the floor.

[0016] Any load on the table leg, especially a vertical load, is transmitted from the threaded spindle via the bearing flange into the base of the support device. The sensor arm is located outside this force flow path. The sensor arm therefore fundamentally does not contribute to the stability or load-bearing capacity of the table leg. This makes it easy to retrofit the sensor arm to an existing table leg. Furthermore, the sensor arm can be easily replaced in the event of a defect.

[0017] When the load, particularly the vertical load, on the table leg changes, the bearing flange and the support device deform slightly, particularly in an area adjacent to the bearing flange. Accordingly, a (minor) change in the position of a point on the bearing flange, particularly the point where the sensor arm touches the bearing flange, occurs relative to a point on the support device, particularly the point(s) where the sensor arm is attached to the support device. These deformations or changes in position can range from a few hundredths to a few tenths of a millimeter.

[0018] By placing the sensor arm against the bearing flange, the aforementioned movements are transferred to the sensor arm, causing it to deform (slightly). This deformation of the sensor arm represents a measure of the load on the table leg. The strain gauge allows the deformation of the sensor arm to be measured. Thus, loads or changes in load on the table leg can be precisely determined using the strain gauge on the sensor arm.

[0019] The strain gauge can have one or more strain gauges. Using a strain gauge, the strain gauge can be set up particularly easily. Furthermore, a strain gauge can precisely measure even the smallest deformations and easily evaluate them. Multiple strain gauges are preferably connected in a quarter, half, or full bridge. This can further improve the measurement accuracy of the strain gauge.

[0020] A control device can be provided to evaluate a signal from the strain gauge. The control device also generally serves to control the motor. In the event of a collision between a table, including the table leg, and an obstacle, the load on the table leg typically changes rapidly and significantly. If the control device detects a corresponding change in the deformation of the sensor arm using the strain gauge, it shuts off the motor. Typically, the control device is configured to reverse the direction of rotation of the motor (and thus the adjustment direction of the table leg) when a collision is detected.

[0021] The sensor arm can have a contact tongue. The contact tongue protrudes from a main section of the sensor arm. The contact tongue can be provided in the form of a projection on the main section. The contact tongue rests against the bearing flange. The main section of the sensor arm generally does not touch the bearing flange. By ensuring that (only) the contact tongue rests against the bearing flange in a defined manner, the accuracy of collision detection can be improved. The contact tongue makes it possible to initiate the relative movement between the bearing flange and the receiving device in a locally limited manner into the main section of the sensor arm. Furthermore, the contact tongue can simplify the arrangement of the sensor arm at a suitable location on the receiving device. In this embodiment, the strain gauge is typically arranged adjacent to the contact tongue on the main section. Recesses can be formed in the main section adjacent to the contact tongue.This further promotes a locally concentrated deformation of the sensor arm in the main section, which is beneficial for the measurement accuracy.

[0022] The contact tongue can have a neck section and two wing sections protruding beyond the neck section on either side. The wing sections rest against the bearing flange. The neck section connects the wing sections to the main section. This can further improve the sensitivity of the strain gauge, particularly with regard to transverse loads on the table leg or tilting of the bearing flange relative to the support device.

[0023] The sensor arm can be attached to the mounting device at both ends. This ensures a stable connection between the sensor arm and the mounting device and can improve the accuracy of the sensor. In this embodiment, the strain gauge is typically located centrally on the sensor arm. Accordingly, the sensor arm typically rests against the bearing flange in a central area, particularly with a contact tongue.

[0024] Alternatively, the sensor arm can be attached to the mounting device at one end and resting against the bearing flange at the other. This allows for a particularly compact sensor arm design.

[0025] The sensor arm can be attached to the base of the support device, for example, by screwing or riveting. This can also promote a compact design of the sensor arm.

[0026] The sensor arm is preferably attached to a side wall of the receiving device, particularly preferably to two opposing side walls of the receiving device. This can improve the accuracy of collision detection, particularly with regard to transverse loads. The side walls typically extend at right angles to the base of the receiving device. The sensor arm can be screwed or riveted to the side wall(s). Fastening elements, such as screws or rivets, are preferably used both to attach the sensor arm to the (respective) side wall and to attach the receiving device to another component, such as a cross member or a table frame. The effort required to integrate the sensor arm can thus be further reduced.

[0027] Particularly preferably, the sensor arm is supported on a rear wall of the receiving device. Rotation of the sensor arm around a fastening element can thus be easily prevented. This particularly simplifies the attachment of the sensor arm to the side walls of the receiving device. The sensor arm can be attached to the side walls by means of two fastening elements, for example rivets, arranged on a common axis. Supporting the sensor arm on the rear wall ensures a defined rotational alignment of the sensor arm with respect to this axis. The rear wall typically extends at right angles to the floor and the side walls.

[0028] The sensor arm can be mirror-symmetrical. The strain gauge is preferably located centrally on the sensor arm. This ensures that loads from opposite directions with respect to the plane of symmetry result in signal changes of equal magnitude in the strain gauge.

[0029] The sensor arm can be a bent sheet metal part. The thickness of the bent sheet metal part can be up to 1 mm. Such a sensor arm can be provided particularly cost-effectively.

[0030] The sensor arm is preferably a die-cast part, particularly preferably a die-cast aluminum part. Such a sensor arm enables particularly precise measurement of the load or load change on the table leg.

[0031] The sensor arm preferably has at least one guide section stiffened by a rib and an unstiffened, typically flat, deformation section. The deformation section can be weakened by indentations. The strain gauge is advantageously arranged in the deformation section. By stiffening the sensor arm outside the area of ​​the strain gauge, the deformation of the sensor arm is concentrated in the area of ​​the strain gauge, i.e., the deformation section. A given change in load on the table leg thus leads to a larger signal change at the strain gauge than with an unstiffened sensor arm. This improves the accuracy of collision detection. The rib is preferably formed integrally with the sensor arm. Table frame according to the invention

[0032] The invention further includes a height-adjustable table frame with at least two height-adjustable table legs. At least one of the table legs is a table leg according to the invention as described above. Preferably, both or all of the table legs are each a table leg according to the invention as described above. The table legs are typically attachable to a cross member of the table frame. The table legs can be fixedly or pivotably attached to the cross member. The table legs can also be attached directly to a table top. Several table frames, each with at least two table legs, can be connected to one another. This allows a jointly height-adjustable arrangement to be created with several table frames or tables.

[0033] In a table frame with two table legs according to the invention, a separate control device can be provided for each table leg to evaluate a signal from the respective strain gauge. Preferably, however, a single, common control device is provided to evaluate signals from the strain gauges of the two table legs. Preferably, the control device is configured to evaluate the signals from the two strain gauges independently of one another. In other words, the control device is configured to check whether the (individual) signal from one of the strain gauges itself indicates a collision. Alternatively, the control device could be configured to derive combined information from the individual signals from the two strain gauges and to evaluate the combined information to detect collisions.The control device can be located in or on the crosshead. Alternatively, the control device can be located in or on the support device or on the tabletop.

[0034] The table frame can have one, preferably two, tabletop supports for a tabletop. The tabletop supports are preferably each attached to the cross member. Alternatively, the tabletop supports can each be attached to one of the receiving devices. Table according to the invention

[0035] Furthermore, within the scope of the present invention is a height-adjustable table comprising a tabletop and a table frame according to the invention, as described above. The tabletop is typically attached to the table frame's plate supports. The sensor system with the sensor arm and the strain gauge allows collisions of the table—in particular, the tabletop, the cross member, and / or the plate supports—with an obstacle to be reliably detected during the height adjustment of the table, and their severity can be effectively reduced by deactivating or reversing the adjustment movement.

[0036] Further features and advantages of the invention will become apparent from the claims, the description, and the drawings. According to the invention, the above-mentioned and further-described features can be used individually or in combination in any convenient way. The embodiments shown and described are not intended to be exhaustive, but rather are exemplary in nature for describing the invention. Detailed description of the invention and drawing

[0037] The invention is illustrated in the drawing and described using exemplary embodiments. They show: Fig. 1 shows a table according to the invention with a table top and a table frame according to the invention, which has two table legs according to the invention, in a schematic perspective view; Fig. 2 shows the table frame of the table of Figure 1in a schematic perspective view; Fig. 3 a first table leg according to the invention with a threaded spindle, which is supported by means of a bearing flange on a base of a receiving device, wherein a sensor arm in the form of a bent sheet metal part is fastened to side walls of the receiving devices and rests with a contact tongue on the bearing flange, in a schematic perspective view; Fig. 4 an enlarged section of Figure 3 , one of the side walls not shown; Fig. 5 the table leg of Figure 3 in a schematic sectional view, with a motor acting on the threaded spindle and a control device symbolically drawn; Fig. 6 the sensor arm of the table leg of Figure 3in a schematic perspective view; Fig. 7 a second table leg according to the invention with a threaded spindle, which is supported by means of a bearing flange on a base of a receiving device, wherein a sensor arm in the form of an aluminum die-cast part is fastened to side walls of the receiving devices and rests with a contact tongue on the bearing flange, in a schematic perspective view; Fig. 8 the sensor arm of the table leg of Figure 7 in a schematic perspective view; Fig. 9 a third table leg similar to Figure 7 , wherein the contact tongue of the sensor arm has two wing sections which bear against the bearing flange, a schematic perspective view; Fig. 10 the sensor arm of the table leg of Figure 9in a schematic perspective view; Fig. 11 a fourth table leg according to the invention with a threaded spindle, which is supported by means of a bearing flange on a base of a receiving device, wherein a sensor arm in the form of an aluminum die-cast part is fastened to the base of the receiving device and rests with a contact tongue on the bearing flange, in a schematic perspective view; Fig. 12 the sensor arm of the table leg of Figure 11 in a schematic perspective view; Fig. 13 a sensor arm in the form of a cantilever arm for one-sided attachment to a base of a receiving device of a table leg according to the invention, wherein the sensor arm has a free end for contacting a bearing flange, in a schematic perspective view; Fig. 14 a fifth table leg according to the invention with a threaded spindle, which is supported by means of a bearing flange on a base of a receiving device, wherein the sensor arm of Figure 13 is attached to the bottom of the receiving devices and rests with a free end against the bearing flange, in a schematic perspective view.

[0038] Figure 1 shows a height-adjustable table 10. Table 10 has a Figure 2 shown table frame 12 and a table top 14 The table frame 12 has a cross member 16 and two plate carriers 18 The table top 14 is held on the table top supports 18. Furthermore, the table frame 12 has two table legs 20 The table legs 20 each have a receiving device 22 and a footrest 24 The reception facilities 22 are located in the Figures 1 and 2 covered by the table top 14 or the cross member 16. The foot parts 24 each comprise a foot extension 26.To adjust the height of the table 10 or the table legs 20, a distance (vertical in the use position) between the support devices 22 and the foot parts 24 can be changed. To detect any collisions that may occur during the height adjustment, a sensor arm is provided on each of the two support devices 22. 28 arranged (in the Figures 1 and 2 shown in dashed lines).

[0039] Figure 3 shows the upper section of a table leg 20 in use position. In Figure 4 is an enlarged section with a bearing flange 30, an upper end of a threaded spindle 32 and the sensor arm 28.

[0040] The receiving device 22 of the table leg 20 is cup-shaped. The receiving device 22 has a bottom 34, two opposite side walls 36 and a back wall 38The side walls 36 and the rear wall 38 protrude vertically from the floor 34. The rear wall 38 can connect the two side walls 36 to each other.

[0041] The bearing flange 30 can be made of several parts. Some of the components of the bearing flange 30 can be made of plastic, in particular fiber-reinforced plastic. The bearing flange can have a soft component, in particular for noise dampening during adjustment.

[0042] The bearing flange 30 is inserted into a recess of the base 34, see also Figure 5 . An outer part 40 of the bearing flange 30 engages on the top and bottom sides over an edge of the recess in the base 34. As a result, the outer part 40 is fixed to the base 34. An inner part 42of the bearing flange 30 is fixed to the threaded spindle 32. The inner part 42 is neither movable nor rotatable relative to the threaded spindle 32. Between the inner part 42 and the outer part 40, a bearing 44, for example, a rolling bearing. The threaded spindle 32 is rotatably supported on the receiving device 22 by the bearing flange 30. Rotation does not cause any (translational) displacement of the threaded spindle 32 relative to the receiving device 22. Forces acting along the threaded spindle 32 are introduced into the base 34 of the receiving device 22 via the bearing flange 30.

[0043] At the upper end, the threaded spindle 32 has a coupling section 46 (see especially Figures 3 and 4 ) for an engine 48 (compare Figure 5). The coupling section 46 can be designed in the form of an external polygon, here a hexagon. The motor 48 can engage directly on the coupling section 46 and be supported on the receiving device 22.

[0044] At the lower end (below the bearing flange 30), the threaded spindle 32 has an external thread section 50 The external thread section 50 engages with an internal thread section 52 a threaded piece 54 of the foot part 24. The threaded piece 54 is held non-rotatably on the foot part 24, here via a piece of pipe 55, which can be made of aluminum. The base part 24 and the receiving device 22 are connected by several, here three, tubular elements 56 connected to each other and fixed in their rotational alignment. A rotation of the threaded spindle 32 thus causes a change in the length or height of the table leg 20 or table 10.

[0045] Figure 6 shows a first variant of the sensor arm 28. The sensor arm 28 is designed according to the Figures 3 to 6 as a bent sheet metal part. A sheet thickness can be less than 1 mm. The sensor arm 28 has a main section 58 and two fastening sections angled relative to the main section 58, here angled at right angles 60 From the main section 58 protrudes a tongue 62 The contact tongue 62 can be angled relative to the main section 60, for example, between 5° and 25°. The sensor arm 28 is mirror-symmetrical with respect to a center plane through the contact tongue 62.

[0046] On the sensor arm 28 there is a strain gauge 64The strain gauge 64 comprises at least one, here two, strain gauges (not shown in detail). The two strain gauges can be connected to form a half-bridge. The strain gauge 64 is attached centrally to the main section 58 of the sensor arm 28 at the level of the contact tongue 62. The strain gauges of the strain gauge 64 can be glued to the sensor arm.

[0047] The main section 58 and the fastening sections 60 could be stiffened on both sides of the strain measuring device 64 by means of ribs not shown in detail, for example embossed beads.

[0048] The sensor arm 28 is connected at both ends by a rivet 66 connected to the side walls 36 of the receiving device 22, compare Figures 3 to 5 . The rivets 66 penetrate recesses in the fastening sections 60 of the sensor arm 28 and in the side walls 36.

[0049] Furthermore, the rivets 66 can penetrate recesses in the cross member 16 and connect the table leg 20 to the cross member 16.

[0050] The sensor arm 28 is supported on the rear wall 38 of the receiving device 22, see in particular Figure 5 . The sensor arm 28 can have extensions 68 (see also Figure 6 ), which rest against the rear wall 38. Due to the rivet connection with the side walls 36 and the contact with the rear wall 38, the sensor arm 28 is firmly fixed to the receiving device 22.

[0051] The sensor arm 28 rests with its contact tongue 62 against the bearing flange 30. Specifically, the contact tongue 62 is placed from above onto the outer part 40 of the bearing flange 30. The sensor arm 28 is designed and secured such that the contact tongue 28 always remains in contact with the bearing flange 30 when the table leg 20 is loaded or unloaded. For this purpose, the sensor arm 28 can be preloaded during assembly.

[0052] When the load on the table leg 20 changes, the bearing flange 30 moves slightly relative to the coupling points for the sensor arm 28 on the support device 22, particularly due to elastic deformation. This leads to a deformation of the sensor arm 28, particularly in the area of ​​the strain gauge 64. The support device 22 and the bearing flange 30 are significantly stiffer than the sensor arm 28. The sensor arm 28 therefore does not contribute significantly to load transfer. The sensor arm 28 merely absorbs the deformation of the support device 22 and the bearing flange 30, so that this can be detected by the strain gauge 64.

[0053] A control device 70monitors the strain gauge 64. The control device 70 also serves to control the motor 48. If the control device 70 detects a rapid and / or significant change in the deformation state of the sensor arm 28 while adjusting the height of the table leg 20 using the strain gauge 64, this indicates a collision. The control device 70 therefore initially switches off the motor 48. Preferably, the control device 70 briefly reverses the motor 48 to release a jam. The control device 70 can also monitor or control the strain gauge 64 and the motor 48 of a second table leg 20 of a table 10.

[0054] Figure 7 shows a similar table leg 20 as the Figures 3 to 5 . The table leg 20 from Figure 7 differs only in the design of its sensor arm 28 from the previously described table leg. The sensor arm 28 of the table leg 20 of Figure 7 is in Figure 8 shown.

[0055] Here, the sensor arm 28 is designed as a die-cast part, preferably an aluminum die-cast part. The sensor arm 28 has a deformation section in the center 72 On both sides of the deformation section 72 there are guide sections 74 The guide sections 74 are each formed by a rib 76 The deformation section 72, in contrast, is flat on the upper side. On the lower side, two recesses 78 introduced into the deformation section 72. The recesses 78 extend on both sides of a contact tongue 62 of the sensor arm 28. A deformation of the sensor arm 28 is therefore concentrated on the deformation section 72. The strain measuring device 64 is fastened to the sensor arm 28 in the deformation section 72, here glued to the top of the sensor arm 28.

[0056] The sensor arm 28 is attached to the side walls 36 via rivets 66, as described above. The sensor arm 28 rests against the rear wall 38 via the ribs 76.

[0057] Figure 9 shows a similar table leg 20 as Figure 7 . The Figure 10 shown sensor arm 28 of the table leg 20 of Figure 9 Except for the design of its tongue 62, corresponds to the Figures 7 and 8 shown sensor arm. In this case, the contact tongue 62 has a neck section 80 which protrudes from the main section 58 of the sensor arm 28. Two wing sections protrude above the neck section 80 82 laterally. The wing sections 82 rest against the bearing flange 30. The wing sections 82 can simulate a curvature of the bearing flange 30.

[0058] Figure 11 shows a similar table leg 20 as the Figures 3 to 5 or 7. The table leg 20 of Figure 11differs only in the design and attachment of its sensor arm 28 from the previously described table legs. The sensor arm 28 of the table leg 20 of Figure 11 is in Figure 12 shown.

[0059] Here, too, the sensor arm 28 is formed as a die-cast part, preferably made of aluminum. Recesses extend through a main section 58 of the sensor arm 28 on both sides of a contact tongue 62.

[0060] According to Figure 11 The sensor arm 28 is attached to the base 34 of the receiving device 22. For this purpose, fastening sections 60 of the sensor arm 28 can protrude from the main section 58 on both sides in the manner of feet.

[0061] Which also in Figure 11 shown side walls 36 as well as the rear wall 40 and an end wall 84could be omitted, so that the receiving device 22 would be plate-shaped. A motor for driving the threaded spindle 32 could then be mounted on a cross member 16.

[0062] Figure 13 shows a further sensor arm 28 for attachment to a base 34 of a receiving device 28 of a table leg 20, compare Figure 14 . Unlike the one in the Figures 11 and 12 The sensor arm shown is the sensor arm 28 of Figures 13 and 14 designed in the manner of a cantilever arm. The sensor arm 28 has a fastening section 60 at one end for attachment to the floor 34. A free end 86 The sensor arm 28 is used to attach to the bearing flange 30.

[0063] In summary, the invention relates to a motor-driven height-adjustable table leg with a sensor system for collision detection located outside the force flow. A rotatable threaded spindle is supported in a bearing flange on a support device. A sensor arm with a strain gauge, which typically has one or more strain gauges, is attached to the support device and rests against the bearing flange without being firmly connected to it. Deformations of the bearing flange and the support device resulting from a change in load are transmitted to the sensor arm and recorded by the strain gauge. List of reference symbols

[0064] Table 10 table frame 12 table top 14 traverse 16 Plate carrier 18 table legs 20 Reception facility 22 Footrest 24 Foot extension 26 Sensor arm 28 bearing flange30 threaded spindle 32 Floor 34 side walls 36 back wall 38 outer part 40 inner part 42 warehouse 44 Coupling section 46 Motor 48 External thread section 50 Internal thread section 52 threaded piece 54 Pipe section 55 Pipe elements 56 Main section 58 Fastening sections 60 Appendix tongue 62 Strain measuring device 64 rivet 66 Appendages 68 Control device 70 Deformation section 72 Guide sections 74 rib 76 Deepenings 78 neck section 80 Wing sections 82 front wall 84 free end 86

Claims

1. A height-adjustable table leg (20) having a receiving device (22) for fastening the table leg (20) to a crossbar (16) of a table support (12) or to a tabletop (14) or to a leg extension (26) or for supporting the table leg (20) on a floor, a threaded spindle (32) and a bearing flange (30), via which the threaded spindle (32) is rotatably supported on a bottom (34) of the receiving device (22), characterized in that a sensor arm (28) having a strain measurement device (64) is fastened to the receiving device (22) and rests against a part of the bearing flange (30) fixed to the bottom (34).

2. The table leg (20) according to claim 1, characterized in that the strain measurement device (64) has a strain gauge.

3. The table leg (20) according to claim 1 or 2, characterized in that the sensor arm (28) has a contact tongue (62) which protrudes from a main portion (58) of the sensor arm (28) and rests against the bearing flange (30).

4. The table leg (20) according to claim 3, characterized in that the contact tongue (62) has a neck portion (80) and two wing portions (82) protruding beyond the neck portion (80) on either side, with which wing portions (82) it rests against the bearing flange (30).

5. The table leg (20) according to any of claims 1 to 4, characterized in that the sensor arm (28) is fastened to the receiving device (22) at both ends.

6. The table leg (20) according to any of claims 1 to 4, characterized in that the sensor arm (28) is fastened to the receiving device (22) at one end and rests against the bearing flange (30) at the other end.

7. The table leg (20) according to any of claims 1 to 6, characterized in that the sensor arm (28) is a bent sheet metal part, wherein preferably a sheet thickness of the bent sheet metal part is at most 1 mm.

8. The table leg (20) according to any of claims 1 to 6, characterized in that the sensor arm (28) is a die-cast part, in particular an aluminum die-cast part.

9. The table leg (20) according to any of the preceding claims, characterized in that the sensor arm (28) has at least one guide portion (74) stiffened by a rib (76) and a deformation portion (72), wherein the strain measurement device (64) is arranged in the deformation portion (72).

10. The table leg (20) according to any of the preceding claims, further comprising a control device (70) for evaluating a signal from the strain measurement device (64).

11. The table leg (20) according to any of the preceding claims, further comprising a motor (48) for rotating the threaded spindle (32).

12. The table leg (20) according to any of the preceding claims, characterized in that the threaded spindle (32) engages a threaded piece (54) of a foot part (24) of the table leg (20).

13. A table support (12) having at least two table legs (20) according to any of the preceding claims and preferably a crossbar (16) to which the table legs (20) can be fastened.

14. The table support (12) according to claim 13, further having a common control device (70) for evaluating signals from the strain measurement devices (64) of the table legs (20), preferably independently of one another.

15. A table (10) having a table support (12) according to claim 13 or 14 and having a tabletop (14).