DE102016110634B4 - Folding table - Google Patents

Abstract

Folding table, which can be adjusted between a lowered position and a set-up position, comprising a cover plate (2) and a base frame (3), a scissor mechanism (4) arranged between the cover plate (2) and the base frame (3), comprising at least two pairs of scissor links (5) each with two scissor links (6, 7) connected to one another via a common scissor link joint, a first scissor link (6) of each pair of scissor links (5) being mounted on the base frame (3) with a first end via a first bearing (8) and with its second End via a second bearing (9) is mounted on the cover plate (2) and a second scissor link (7) of each pair of scissor links (5) is mounted with a first end via a third bearing (10) on the cover plate (2) and with its second End via a fourth bearing (11) is mounted on the base frame (3), a link arrangement (12) on each pair of scissors links (5), comprising a first link (13) on the first scissor link (6) and one second link (14) on the second scissor link (7), the two links (13, 14) interacting via a bolt (19), a spring arrangement (15) which biases the folding table (1) in the erected position, comprising at least one centering spring (18) per pair of scissor links (5), which is mounted with a first end on the cover plate (2) and a second end on the bolt (19) which forms the scissor link joint, and a self-locking drive (20) which is connected to a scissor link (7) is non-rotatably connected and adjusts the folding table (1) between the lowered position and the set-up position, the drive comprising a power-split reduction gear.

Description

The invention relates to a folding table which can be adjusted between a lowered position and an erected position.

Folding tables known to date, which can be adjusted between a lowered position and a set-up position, comprise at least a cover plate, a base frame or a base plate and a scissor mechanism arranged between the cover plate and the base frame. The scissor mechanism comprises at least two pairs of scissor links, each with two scissor links connected to one another via a common joint. Each scissor link is supported by a corresponding bearing with a first end on the base frame and with a second end on the cover plate. The scissors mechanism is moved by a drive so that the cover plate can be raised by the scissors mechanism relative to the base frame in order to be able to adjust the folding table from its lowered position, in which the cover plate is stored, to its set-up position, in which the cover plate is raised .

Previously known scissor mechanisms are adjusted by a drive which includes spindles or can be designed as a worm drive.

In the case of automatic battery charging systems in vehicles in particular, such drives are problematic due to their self-locking effect. An automatic battery charging system is understood to mean a device in which, as desired, corresponding actuating elements can be moved in such a way that a current flow is established between a current source and a current consumer. The self-locking drives of known tables result in a rigid mechanism. In the event of an overload acting on the folding table, for example, the table can jam due to a collision with an object or a vehicle underbody, or the scissor mechanism is damaged, for example by bending or breaking.

Due to the self-locking effect, previously known drives for folding tables have a large design. For this reason, very large drives have hitherto been necessary to adjust the folding table, which means that a flat and low folding table cannot be implemented. However, since the space between a floor and a vehicle underbody is small, there is a need for improvement in the previously known folding tables in this regard.

Since the scissors mechanism is folded up very compactly in the lowering position of the folding table, a great deal of force is required to overcome an initial resistance that occurs when the folding table is moved into the set-up position. This is why very large bearing forces occur especially with spindle drives in the lowered position. A very compact folded scissor mechanism is provided if the individual scissor members are aligned parallel or at least approximately parallel to the ground in the lowered position. The compactness of the folded scissor mechanism takes into account the small installation space between a floor and a vehicle underbody.

To overcome the initial resistance, very large drive torques are required at the beginning of the adjustment movement from the lowered position to the erected position. With increasing travel in the direction of the set-up position, the lever ratios in the scissor mechanism change particularly strongly, which means that the drive torques do not remain constant over the travel path, but vary greatly, and leads to the fact that known folding tables shoot up after overcoming the initial resistance can. In addition, previously known drives must be designed so strong that they can overcome the existing initial resistance, which, however, means that they are greatly oversized for the travel in the direction of the installation position after overcoming the initial resistance.

In addition, non-reversible and non-torque-limited drives do not provide adequate protection against collision or trapping.

Folding tables are also known in which a scissor mechanism is mounted on plain bearings on the bottom. However, dirt and water can collect there and, for example, lead to jamming or blocking of the bearing due to icing, whereby the operation of the folding table is severely impaired or even impossible.

Furthermore, from the DE 195 49 088 A1 a lifting table with a base frame, a support frame (stage, table top), a scissor mechanism arranged between the frame and an adjusting device with an electric drive are known.

Furthermore, a folding table with a self-locking drive cannot be designed in such a way that, for example, in the event of a power failure, the cover plate can be quickly lowered into the lowered position.

The invention is therefore based on the object of creating a folding table which overcomes the problems described above and which is as uniform as possible due to a flat embodiment, a high level of safety, in particular with regard to behavior in the event of a power failure and operation Drive torques and an improved movement behavior to external forces.

This object is achieved according to the invention by the folding table with the features of claim 1.

According to the invention, a folding table is proposed which is adjustable between a lowered position and a set-up position. The folding table comprises a cover plate and a base frame, a scissor mechanism arranged between the cover plate and the base frame, comprising at least two pairs of scissor links each with two scissor links connected to one another via a common scissor link joint, a first scissor link of each pair of scissors with a first end via a first bearing on the Floor frame and is mounted with its second end via a second bearing on the cover plate and a second scissor link of each pair of scissors link is mounted with a first end via a third bearing on the cover plate and is mounted with its second end via a fourth bearing on the base frame. In addition, the folding table has a link arrangement on each pair of scissor links, comprising a first link on the first scissor link and a second link on the second scissor link, the two links interacting via a bolt. Furthermore, the folding table comprises a spring arrangement which biases the folding table in the set-up position, comprising at least one centering spring for each pair of scissor links, which is mounted with a first end on the cover plate and with a second end on the bolt that forms the scissor link joint. The folding table comprises a non-locking drive which is connected to a scissors member in a rotationally fixed manner and which adjusts the folding table between the lowered position and the set-up position, the drive comprising a power-split reduction gear.

The folding table according to the invention is based on the knowledge that the interaction of a self-locking-free drive on the one hand and on the other hand with a scissor mechanism, a link and spring arrangement that solves problems known from the prior art.

By means of the floor frame, the folding table can either be fixed in a stationary manner on a floor, on a wall, on a ceiling or also in a mobile manner on a movable device that supports the folding table.

The cover plate is adjustable with respect to the base frame, whereby it can, for example, carry a load or also an electrical contact, which can close an electrical circuit when a contact is made with a corresponding mating contact. For example, if the folding table is designed as an element of an automatic battery charging system for vehicles, a vehicle can be positioned above, next to or below the folding table. The position of the vehicle in relation to the folding table of the battery charging system can be determined via the arrangement of the mating contact on the vehicle. The folding table can then be moved from its lowered position to its set-up position, so that a contact connection between the contact carried by the cover plate and the mating contact arranged on the vehicle and a current flow can take place either in the direction of or from the direction of the vehicle. It is also conceivable that the cover plate carries a capacitor or a coil, which are used for capacitive or inductive coupling with a corresponding counterpart arranged on a vehicle. An energy store of an electric vehicle can thus be charged or discharged without contact.

The scissor mechanism can be folded up very compactly in order to achieve a very flat design of the folding table, or the individual scissor elements are aligned parallel or at least approximately parallel to the floor in the lowered position.

A link arrangement is provided on each pair of scissor links which comprises two links which work together in order to synchronize the two scissor links of a pair of scissors with one another. They can, for example, be congruent at least in sections in every position of the folding table or be aligned with one another in the transverse direction of the folding table and be penetrated by the bolt which forms the scissor link joint. In other words, the two scissor members can be pivotably connected to one another via the bolt. Since the bolt forms the scissor link joint, it also lies in a vertical transverse center plane of the folding table in every position of the folding table.

The centering springs of the spring arrangement bias the table into its set-up position, the spring force of the centering springs mainly acting towards the end of the adjustment path from the lowered position into the set-up position.

At least one centering spring of the spring arrangement is arranged between the cover plate and each bolt and centers the cover plate with respect to the vertical transverse center plane of the folding table.

In order to achieve a constant and, above all, short travel time at high travel speed, the scissor mechanism of the folding table must be balanced in such a way that a drive torque that is as constant and as low as possible is required. The folding table according to the invention can with a such low drive torque can be adjusted because it represents a balanced system. This balance is achieved by the self-locking-free drive on the one hand and the scissor mechanism, the link arrangement and the spring arrangement on the other. A so-called UNIMOT, which represents an electric motor, with a load torque lock, a power split, a reduction and a torque limiter, is particularly suitable as a drive. Because the spring arrangement biases the folding table in the direction of the set-up position, only a small drive is required to overcome the initial resistance for moving the cover plate into the set-up position of the folding table.

By means of the spring arrangement and the link arrangement, it is also possible to adjust the folding table with largely constant drive torques between the lowered position and the set-up position. This is achieved in that the spring arrangement biases the folding table in the erected position and thus compensates for the initial resistance when moving the folding table from the lowered position to the erected position. The drive therefore no longer has to introduce a high torque at the beginning of the adjustment path, which decreases as the adjustment path increases, since the resistance becomes lower. As a result, a small drive can be used.

Due to the interaction of the drive with the spring arrangement and the link arrangement, the resistance during adjustment is also largely the same over the entire adjustment path, whereby the drive torque required for adjustment can advantageously remain largely constant.

Since the folding table according to the invention comprises a self-locking drive with a power-split reduction gear, there is a high overall efficiency. It is therefore possible to use a small drive which makes a very flat folding table possible.

The power-split reduction gear, by virtue of its reversibility, means that the folding table can react to external forces in an advantageous manner. If a force is applied in the erection direction or with at least one force component in the erection direction on the cover plate of the folding table, the folding table gives way due to the interplay of scissors mechanism, link arrangement, spring arrangement and drive with a power-split reduction gear. In other words, if a large force acts on the folding table, the power-split reduction gear is used to allow this excessive force to pass through. This means that the table can react flexibly to external forces. If the acting force decreases or disappears completely, the table can be returned to its starting position or erected position by means of the spring arrangement and the drive. Thus, with the action of an external force, the folding table in its set-up position or the cover plate in the set-up position of the folding table can perform a nodding movement, a rolling movement and / or a yawing movement. Such an embodiment is particularly advantageous in the event of a collision with a vehicle underbody.

Due to the power-split reduction gear, if there is no external power supply to the folding table, it is also possible to move the folding table into its lowering position.

A mechanical limitation of the drive torque in the drive ensures adequate and efficient anti-trap protection.

In a preferred embodiment of the folding table according to the invention, the second bearing and the third bearing are designed as sliding bearings and the corresponding bearing housings are fixed to the cover. The sliding bearings are arranged between the scissor members and the cover plate in such a way that the cover plate can be moved in the longitudinal direction of the scissor members. When there is contact between the folding table and a vehicle underbody, a relative movement between the vehicle and the folding table in the longitudinal direction of the scissor members can thus be compensated for. The ends of the scissor links mounted in the second and third bearings can for example be guided in bearing links in such a way that the bearing links realize a stop and thus limit the mobility of the cover plate in the longitudinal direction of the scissor links. Since, in an embodiment as a folding table arranged on a floor, the second and third bearings, which are designed as sliding bearings, are covered at the top by the cover plate, they cannot jam or block due to environmental influences such as dirt, water or ice.

It is also conceivable that the first bearing and the fourth bearing are optionally adjustable between a sliding bearing and a pivot bearing, the corresponding bearing housings being fixed to the floor on the base frame. The movement of the first and fourth bearings between a sliding bearing and a pivot bearing can be limited by means of a limiting pin which can be inserted into the bearing or into the bearing link. If all the first and fourth bearings are in the configuration as sliding bearings, the cover plate of the table can be moved into the set-up position, the cover plate moving exclusively in a projection area which is oriented orthogonally to the top of the cover plate. In other words, the cover plate does not perform any lateral movement in the longitudinal direction of the scissor links. One on the side Movement of the cover plate when it is set up in the set-up position of the folding table takes place when either the first or the fourth bearing is in the configuration as a pivot bearing and the other bearings of the floor-mounted bearings are in the other configuration. Then namely the opposite bearing of the corresponding scissors member as a pivot bearing moves on a circular path around the pivot bearing, which inevitably results in a lateral movement of the cover plate in the direction of the pivot bearing designed as a first or fourth bearing. Thus, depending on the position of the limiting pin in the first and / or second bearings, rotary fixed bearings, rotary loose bearings, translational fixed bearings and translational floating bearings can be configured. This depends on whether and how the limiting pin is fixed in the bearing by means of a screw or a locking ring, for example. Such configurations are also conceivable for the second and third bearings.

In a further preferred embodiment of the folding table according to the invention, the scenes are arcuate and open in the direction of the base frame. The two links of a link arrangement are arranged on the scissors members of a pair of scissors links that a first link of the link arrangement extends from the joint connecting the two scissor links of the pair of scissors to one another in the longitudinal direction of the scissor links in one direction and the second link of the link arrangement extends into the other Direction extends, wherein the bolt forms the joint connecting the two scissor links and can reach through the area which is aligned with one another at least in sections in the transverse direction of the folding table. During the lifting of the cover plate and the adjustment of the folding table from the lowered position to the set-up position, the two scenes of a link arrangement are moved towards each other in such a way that they are moved to the side with respect to the joint which is opposite their position in the lowered position. That is, when looking at the pair of scissor links in their transverse direction, a gate that extends to the right in the lowered position moves from the right side with respect to the joint to the left side with respect to the joint. Correspondingly, a link extending to the left with respect to the joint in the lowered position is moved to the right side with respect to the joint when the folding table is set up. In other words, the two scenes of a scene arrangement cross each other when the folding table is set up and lowered. The curved design of the connecting links that opens towards the base frame ensures that the bolt connected to the at least one centering spring always moves in a transverse center plane of the folding table. When it comes to the opening direction of the scenes, it is crucial that they open in the direction of the lowered position. For example, if the folding table is attached to a wall and the floor frame is used as a wall frame, or if the folding table is attached to a ceiling and the floor plate is used as a ceiling frame, the scenes always open in the direction of the wall frame or ceiling frame.

It is also conceivable that each link comprises a lowered position section into which the bolt moves in the lowered position, and a set-up section into which the bolt moves in the set-up position. Thus, in the lowering position of the folding table, the section of the spring arrangement which is aligned with one another in the transverse direction of the folding table is realized by covering or overlapping the two lowering position sections of the two scenes of a link arrangement. Analogously to this, when the folding table is set up, the section of the two scenes of a link arrangement that is aligned with one another in the transverse direction of the folding table is implemented by the overlapping or overlapping of the two set-up sections with one another. In other words, in the lowered position, the two lowered position sections of a link arrangement are arranged in the folding table transverse central plane, while the two erection sections are arranged on both sides of the folding table transverse central plane. Analogously to this, in the set-up position, the two set-up sections of the link arrangement are arranged in the table transverse center plane and the two lowering position sections are arranged on both sides of the table transverse center plane.

It is also conceivable that each centering spring is assigned to a scissor link and thus extends in the longitudinal direction of the corresponding scissor link. The arrangement of two centering springs per pair of scissors links ensures that the bolt, on which two centering springs are arranged, is centered in the folding table transverse center plane in every movement position of the folding table. In the lowered position, the two centering springs on a pair of scissor links thus have an angle of approximately 170 ° spanned between them. If the folding table is adjusted to its set-up position, the angle enclosed by the two centering springs of a pair of scissor links is reduced to about 100 °. The centering is realized in that one centering spring pulls the bolt to one side with respect to the table transverse center plane and the other centering spring pulls the bolt to the same extent to the other side with respect to the table transverse center plane. Such an arrangement of centering springs also has the advantage that when sliding bearings are used for the second and third bearings, the cover plate is centered with respect to the table transverse center plane by the spring force of the centering springs.

It is also conceivable that the drive comprises a geared motor which drives a pinion shaft which is parallel to one of the scissor links interconnecting main shaft is arranged and whose two ends are each assigned a pinion. At both ends of the main shaft, the main shaft has a toothed segment that is fixed to the main shaft and is meshed by the pinion.

In this embodiment, the pinion shaft serves to introduce a force emanating from the geared motor uniformly into both pairs of scissor links. However, it is also conceivable to dispense with such a pinion shaft in order to save space or for reasons of cost. In such an embodiment, the drive would comprise a geared motor which drives a pinion which meshes with a corresponding tooth segment on the main shaft. The power transmission from the one pair of scissors links, on which the gear motor is arranged, to the pair of scissors links opposite the longitudinal center plane of the folding table could take place via the main shaft.

The force is introduced, starting from the geared motor, into only one scissor link of a pair of scissors links. The scissors member driven by the geared motor moves and, due to the forced coupling between the two scissors members of a pair of scissors members, takes along the scissors member which is not driven or which is arranged on the output side. In other words, the action of the drive on one scissor link and the forced coupling as well as the output on the other scissor link ensures that both scissor links always receive the same torque. As a result, the cover plate of the folding table moves evenly in a vertical direction or in a horizontal orientation, despite the inherently flexible scissor mechanism.

It is conceivable that the drive of the folding table includes a brake that locks the folding table in the lowered position. The power-split transmission can interact with this. Because a differential makes it possible to direct the drive torque with a locked folding table to the unlocking of the folding table until the folding table is unlocked and can be moved itself. In other words, the power split ensures that the folding table is locked in the lowered position by means of the brake. If the folding table is to be moved from the lowered position to the set-up position, the motor starts up and applies torque to the gearbox, which first releases the brake. Only after releasing the brake is the torque from the gearbox introduced into the scissor mechanism itself, which leads to the folding table being adjusted. The adjustment of the folding table from the erected position to the lowered position takes place in the opposite way.

In a further preferred embodiment of the folding table according to the invention, the drive comprises an emergency energy store, which supplies the drive with energy as required. Such an embodiment is particularly advantageous if an external power supply fails. Due to the self-locking-free drive, the folding table according to the invention, in contrast to folding tables known from the prior art with spindle drives, can be moved in a simple manner from the erected position into the lowered position. This can be done very quickly by supplying the drive with energy from the emergency energy store. The energy present in the emergency energy store is sufficient to move the folding table from the erected position to the lowered position against the spring force of the spring arrangement. Since such an adjustment can also take place in a very short time, a rapid retraction is guaranteed, which enables a vehicle arranged above the folding table to leave a charging station as quickly as possible even during a failure of the external power supply. However, it is also conceivable to adjust the folding table manually, for example by pressing the cover plate, into the lowered position.

It is also conceivable that the geared motor and / or at least one bearing includes a protection that can be designed according to IP 67 protection class in accordance with DIN 40050-9: 1993-05. With such a seal or such an encapsulation of the geared motor and / or at least one bearing, the protected components have weather protection and foreign body protection.

In a further preferred embodiment of the folding table according to the invention, the spring arrangement, which biases the folding table in the erected position, furthermore comprises the following: at least one erect spring, which acts between the cover plate and the base frame, and at least one pair of springs on each pair of scissors, the pair of springs comprising two centering springs is formed and each centering spring is mounted with a first end on the cover plate and with a second end on a bolt which forms the scissor link joint and engages through the aligned portion of the link arrangement. The erecting spring of the spring arrangement biases the table into its erecting position, the spring force of the erecting spring acting predominantly at the beginning of the adjustment path from the lowered position into the erecting position. The tension springs of the spring arrangement bias the table into its set-up position, the spring force of the tension springs acting predominantly towards the end of the adjustment path from the lowered position into the set-up position.

In a further preferred embodiment of the folding table according to the invention, the raising spring is and / or are designed as a leg spring the centering springs are designed as tension springs. In such an embodiment, the spring designed as a leg spring compensates for the weight of the folding table at the beginning of the erecting movement. Thus, the raising spring serves to overcome the initial resistance and thus leads to a constant drive torque. The tension springs in turn compensate for the weight of the folding table predominantly in the extended state or in the set-up position. The tension springs therefore contribute to a constant drive torque. The coulisse arranged in the scissor members with the bolt guided therein serve a flowing and uniform transition between the position of the folding table, in which the raising spring predominantly acts, and the position of the table, in which the centering springs predominantly act. The link arrangement thus serves to ensure the evenness of the movement of the folding table.

Further advantages and advantageous configurations of the subject matter of the invention can be found in the description, the drawing and the claims.

• 1 eine perspektivische Darstellung eines Falttisches nach der Erfindung in seiner Absenkstellung;
• 2 eine perspektivische Darstellung des Falttisches in seiner Aufstellstellung;
• 3 eine Seitenansicht der Scherenmechanik in Absenkstellung;
• 4 eine Draufsicht auf die Scherenmechanik in der Absenkstellung;
• 5 eine perspektivische Darstellung eines Antriebs;
• 6 eine perspektivische Darstellung einer alternativen Ausführungsform des Antriebs;
• 7a eine schematische Darstellung einer Kulissenanordnung in Absenkstellung;
• 7b eine schematische Darstellung der Kulissenanordnung in Aufstellstellung;
• 8 eine perspektivische Darstellung eines Motorträgers;
• 9 eine perspektivische Darstellung der Kulissenanordnung in Aufstellstellung;
• 10 einen Schnitt des Falttisches nach 1 entlang der Linie X-X in 4;
• 11a einen Schnitt der Lager des Falttisches nach 1 entlang der Linie XIa-XIa in 3;
• 1 1b einen Schnitt der Lager des Falttisches nach 1 entlang der Linie XIb-XIb in 3;
• 12 ein Diagramm eines Drehmomentverlaufs über den Verstellweg zwischen der Absenkstellung und der Aufstellstellung des Falttisches; und
• 13 ein Diagramm eines Kraftverlaufs über den Verstellweg zwischen der Absenkstellung und der Aufstellstellung des Falttisches.

An embodiment of a folding table according to the invention is shown schematically simplified in the drawing and is explained in more detail in the following description. It shows:

• 1 a perspective view of a folding table according to the invention in its lowered position;
• 2 a perspective view of the folding table in its set-up position;
• 3 a side view of the scissors mechanism in the lowered position;
• 4th a plan view of the scissors mechanism in the lowered position;
• 5 a perspective view of a drive;
• 6th a perspective view of an alternative embodiment of the drive;
• 7a a schematic representation of a gate arrangement in the lowered position;
• 7b a schematic representation of the gate arrangement in erection position;
• 8th a perspective view of an engine mount;
• 9 a perspective view of the link arrangement in the erected position;
• 10 a section of the folding table 1 along the line XX in 4th ;
• 11a a section of the bearing of the folding table 1 along the line XIa-XIa in 3 ;
• 1 1b shows a section of the bearing of the folding table 1 along the line XIb-XIb in 3 ;
• 12th a diagram of a torque curve over the adjustment path between the lowered position and the set-up position of the folding table; and
• 13th a diagram of a force curve over the adjustment path between the lowered position and the erection position of the folding table.

In 1 is a folding table 1 shown according to the invention, which is adjustable between a lowered position and an erected position. The folding table 1 is by means of a self-locking drive 20th adjusted with a power-split reduction gear, resulting in a high overall efficiency. It is therefore possible to use a small drive which makes a very flat folding table possible.

The folding table 1 includes a cover plate 2 and a floor rack 3 . The cover plate 2 is opposite the floor frame 3 adjustable and can, for example, carry a load or an electrical contact, a capacitor or a coil, if the folding table 1 forms an element of an automatic battery charging system for vehicles, the battery charging system being able to operate capacitively, inductively or in some other way. By means of the floor frame 3 is the folding table 1 either stationary on a floor, on a wall, on a ceiling or mobile on a folding table 1 load-bearing and movable device can be fixed.

Between the cover plate 2 and the floor frame 3 is a scissor mechanism 4th arranged. The scissor mechanism 4th is in the in 1 shown lowered position of the folding table 1 folded and comprises a pair of scissor links on both sides of a vertical longitudinal center plane of the folding table 5 . Each pair of scissor links 5 includes two over one of a bolt 19th formed common scissor link joint interconnected scissor links 6th , 7th . The two scissor links 7th of the two pairs of scissor links 5 are by means of a synchronous bracket 33 firmly connected.

The first scissor link 6th each pair of scissor links 5 is each with a first end over a first bearing 8th on the floor frame 3 stored and with its second end over a second bearing 9 on the cover plate 2 stored. The second scissor link 7th each pair of scissor links 5 is in each case with its first end over a third bearing 10 on the cover plate 2 and with its second end over a fourth bearing 11 on the floor frame 3 stored.

Each pair of scissor links 5 includes a backdrop arrangement 12th which is a first backdrop 13th on the first scissor link 6th and a second backdrop 14th on the second scissor link 7th includes.

As in particular in 2 can be seen, includes the folding table 1 a spring assembly 15th showing the folding table 1 pre-tensioned in the installation position. The spring arrangement 15th includes an erecting spring designed as a leg spring 16 , what a 1 is hidden and one leg is attached to the cover plate 2 and with its other leg on the floor frame 3 supported and between the cover plate 2 and the floor frame 3 works. The deployment spring 16 the spring arrangement 15th tightens the folding table 1 into its deployment position, the spring force of the deployment spring 16 acts predominantly at the beginning of the adjustment path from the lowered position to the set-up position. The spring arrangement also includes 15th two pairs of springs 17th , with each pair of springs 17th on a pair of scissor links 5 is arranged.

The scissor mechanism 4th is to realize a very flat design of the folding table 1 very compact foldable, like 4th shows. The individual scissor links 6th , 7th are aligned parallel or at least approximately parallel to the floor in the lowered position shown.

How in particular 3 shows is each pair of springs 17th made of two centering springs designed as tension springs 18th educated. Any centering spring 18th has a first end at the in 3 cover plate, not shown 2 and with a second end on the bolt 19th stored. The bolt 19th forms the scissor link joint and extends through the aligned section of the link arrangement 12th , as well as in particular in the 7a and 7b shown. The centering springs 18th the spring arrangement 15th serve to center the cover plate 2 with respect to the vertical transverse center plane of the folding table.

Any centering spring 18th is a corresponding scissor link 6th , 7th assigned and thus runs in the longitudinal direction of the corresponding scissor link 6th , 7th . This ensures that the bolt 19th , on which two centering springs 18th attack, in every movement position of the folding table 1 is centered in the folding table transverse center plane. The centering is realized in that a centering spring 18th a pair of springs 17th the bolt 19th pulls to one side with respect to the table's transverse center plane and the other centering spring 18th of the pair of springs 17th the bolt 19th to the same extent on the other side with respect to the table's transverse center plane. Such an arrangement of centering springs 18th also has the advantage that when using sliding bearings for the second bearing 9 and third camp 10 the cover plate 2 by the spring force of the centering springs 18th is centered with respect to the table transverse median plane. The two centering springs point in the lowered position 18th on a pair of scissor links 5 an angle spanned between them of about 170 °. Will the folding table 1 Adjusted to its installation position, that of the two centering springs is reduced 18th a pair of scissor links 5 included angles to about 100 °.

The centering springs 18th the spring arrangement 15th tension the folding table 1 in its installation position, the spring force of the centering springs 18th acts predominantly at the end of the adjustment path from the lowered position into the set-up position.

4th shows a top view of the scissors mechanism 4th of the folding table according to the invention 1 , with the cover plate 2 and the floor rack 3 are hidden. In particular, in 4th the arrangement of a non-self-locking drive 20th on the scissor mechanism 4th shown.

The self-locking drive 20th is with the scissor links 7th each pair of scissor links 5 each via a motor mount 30th non-rotatably connected. The drive 20th is used to adjust the folding table 1 between the lowered position and the erected position, with the drive 20th a gear motor designed as an electric motor or UNIMOT 21 includes with a power split reduction gear. The drive 20th that on one scissor link 7th acts, and the forced coupling of the two scissor links 6th , 7th a pair of scissor links 5 make sure both scissor links 6th , 7th always get the same moment. This causes the cover plate to move 2 of the folding table 1 despite the inherently flexible scissor mechanism 4th evenly in a vertical direction or in a horizontal orientation.

With the gear motor 21 is a pinion shaft 22nd connected which from the gear motor 21 is driven. The pinion shaft encompasses both sides of the vertical center plane of the table 22nd a pinion at both ends 23 . In addition, the pinion shaft is 22nd parallel to one of the two pairs of scissor links 5 interconnecting main shaft 24 arranged. In both end areas of the main shaft 24 is each one with the main shaft 24 moving bolt 19th arranged. The main shaft has on both sides of a vertical longitudinal center plane of the folding table 24 In addition, a tooth segment fixed to the main shaft in each of its two end areas 25th on. The tooth segment 25th is used to adjust the folding table 1 from the pinion 23 the pinion shaft 22nd combed. The pinion shaft 22nd serves to one of the geared motor 21 outgoing force equally in both pairs of scissor links 5 initiate.

5 shows the drive of the folding table in isolation, with each tooth segment 25th a storage process 26th includes. Between the storage processes 26th of the tooth segments 25th is a synchronous shaft 27 arranged, which is parallel to the main shaft 24 and can be swiveled around it is arranged. The synchronizer shaft 27 serves the stability of the scissor mechanism 4th and the even distribution of the forces occurring in the two pairs of scissors 5 . By means of the pinion shaft 22nd and the synchronizer shaft 27 are the two pairs of scissor links 5 Connected to one another in a torsionally rigid manner in order to obtain a minimum rigidity of the folding table in the event of a rolling movement or in the event of a swaying of the folding table about an axis running in the longitudinal direction of the folding table.

The drive 20th also includes a brake 28 , which has a brake hook 29 which includes the folding table 1 locked in its lowered position. With the brake 28 the power-split transmission can work together. A differential makes it possible to reduce the drive torque with a locked folding table 1 first on the unlocking of the folding table 1 or on the brakes 28 to head up the folding table 1 or the brake 28 is unlocked and can be operated by yourself. In other words, the power split ensures that the folding table 1 in the lowered position by means of the brake 28 is locked. Should the folding table 1 are moved from the lowered position to the erected position, the geared motor moves 21 and introduces a torque into the transmission, which initially applies the brake 28 solves. Only after releasing the brake 28 the torque from the gear into the scissor mechanism 4th even initiated what to adjust the folding table 1 leads. The adjustment of the folding table 1 from the erected position to the lowered position takes place in the opposite way. The hardness of the brake 28 is by means of an adjustment device 40 adjustable.

The drive is on both sides of the vertical center plane of the folding table 20th via the engine mount 30th on the scissor links 7th stored.

The gear motor 21 also has a weather and foreign body protection, which can be implemented according to IP67 - protection class according to DIN 40050-9: 1993-05.

6th shows an alternative embodiment of a drive 20th that are opposite the in 5 The embodiment shown is characterized in that only one pair of scissor links 5 from the drive 20th is driven. To avoid repetition, only the differences in the in 6th shown drive 20th to the in 5 illustrated drive explained.

The gear motor 21 drives a single pinion 23 on, both on the pinion shaft 22nd as well as a second pinion 23 on the other pair of scissor links 5 is waived. For adjusting the folding table 1 the torque is thus only via the one pinion 23 in a tooth segment 25th registered. By the from the main shaft 24 Conditional forced coupling of the two pairs of scissor links 5 is also the non-driven pair of scissor links 5 adjusted so that the folding table 1 is evenly adjustable. In addition, the power transmission could be from one pair of scissor links 5 on which the gear motor 21 is arranged, to the pair of scissors members opposite the longitudinal center plane of the folding table 5 over the main shaft 24 take place.

Using the in the 5 and 6th shown alternatives of a drive 20th there are also two possibilities, the two pairs of scissor links 5 to synchronize with each other and to generate two stiffnesses of a rolling movement. In addition, the in 5 The synchronization shown is stiffer than that in 6th shown, the rolling motion of the pinion shaft 22nd depends. In the 6th The synchronization shown, however, is due to the lack of a second pinion 23 and a second engine mount 30th softer than the in 5 synchronization shown.

To make the 7a and 7b is the one on the first scissor link 6th arranged first backdrop 13th by means of a solid line and the one on the second scissor link 7th arranged second backdrop 14th represented by a dashed line. A synopsis of the 7a and 7b illustrates the position of the two scenes 6th , 7th the arrangement of the scenery 12th both in the lowered position and in the set-up position of the folding table 1 . The scenes 13th , 14th the scissor links 6th , 7th are curved and in the embodiment shown open downwards or towards the floor. The two backdrops 13th , 14th form identical arcs.

As the 7a and 7b show, the two scenes are aligned 13th , 14th in the transverse direction of the folding table, at least in sections, with one another or in every position of the folding table 1 a congruent section. The bolt is in the congruent section 19th recorded. In other words, are the two scissor links 6th , 7th over the bolt 19th pivotally connected to each other. Because the bolt 19th forms the scissor link joint, it is also in every position of the folding table 1 in a vertical transverse center plane of the folding table.

Any setting 13th , 14th includes a lowering section 31 in which the bolt 19th retracts in the lowered position, as in 7a shown. Any setting 13th , 14th also includes an installation section 32 in which the bolt 19th in the setting up of the folding table 1 retracts as in 7b shown.

While lifting the cover plate 2 and adjusting the folding table 1 the two become from the lowered position to the erected position Backdrops 13th , 14th a backdrop arrangement 12th so moved towards each other that they are on the side with respect to the bolt 19th are moved, which is opposite their position in the lowered position. That is, when looking at the pair of scissor links 5 The first gate, which extends to the right in the lowering position, moves in the transverse direction of the folding table 13th from the right side with respect to the bolt 19th to the left with respect to the bolt 19th . Correspondingly, it will move to the left with respect to the bolt 19th in the lowered position extending backdrop 14th when setting up the folding table 1 on the right side with respect to the bolt 19th emotional. In other words, the two scenes cross 13th , 14th a backdrop arrangement 12th when setting up and lowering the folding table 1 . Due to the arched and downward opening design of the scenes 13th , 14th it is guaranteed that the with the centering springs 18th and the main shaft 24 connected bolts 19th always moved in a folding table transverse center plane.

8th Figure 3 shows a perspective view of the engine mount 30th on a pair of scissor links 5 . The motor mount is from the pinion shaft 22nd penetrated, at the end of which a pinion 23 for combing a tooth segment 25th is arranged. In addition, is on the engine mount 30th the main shaft 24 stored.

In 9 Figure 3 is a perspective view of a gate assembly 12th shown in the installation position, with the two centering springs 18th on the bolt 19th attack. The bolt 19th has a guide element 34 on, which has a guide nose corresponding to the link shape. The guide nose is in the overlap area of the two scenes 13th , 14th guided. In addition, both scenes point 13th , 14th a circumferential protective radius 35 which serves to avoid sharp edges and to protect the material.

10 shows a section of the folding table 1 after 1 along the line XX in 4th . The cut runs in the transverse direction of the folding table through the pinion shaft 22nd . An output torque of the brake represented by a first arrow 35 runs based on the drive motor that is perpendicular to the plane of the drawing 21 by a planetary gear. Due to the torque-dependent power split, the output torque is 35 starting from the in 10 shown storage position for releasing the brake 28 on the brakes 28 directed. Only after releasing the brake 28 can be an output torque symbolized by a second arrow 36 the brake 28 happen and into the pinion 23 be entered in order to adjust the folding table.

the 11a and 11b show different configurations of the bearings 8th , 9 , 10 , 11 . The movement limitation of the bearings 8th , 9 , 10 , 11 between a sliding bearing and a pivot bearing can by means of a limiting pin 37 take place, which in the warehouse 8th , 9 , 10 , 11 or in one of the camps 8th , 9 , 10 , 11 arranged storage backdrop 38 can be used. When all first camp 8th and fourth camp 11 in the configuration as a sliding bearing, the cover plate 2 of the folding table can be moved into the installation position, with the cover plate 2 moved exclusively in a projection area which is orthogonal to the top of the cover plate 2 is aligned. In other words, the cover plate leads 2 no lateral movement in the longitudinal direction of the scissor links 6th , 7th the end. A lateral movement of the cover plate 2 in the longitudinal direction of the scissor links 6th , 7th when setting up the folding table 1 occurs when either the first camp 8th or the fourth camp 11 in the configuration as a pivot bearing and the other bearings of the floor-mounted bearings in the other configuration. Then that is because the bearing of the corresponding scissors member, which is opposite the pivot bearing, moves on a circular path around the pivot bearing, which inevitably results in a lateral movement of the cover plate in addition to the erecting movement 2 takes place in the direction of the first or fourth bearing designed as a pivot bearing. Thus, depending on the position of the limiting pin 37 in the camp scenery 38 Rotary fixed bearings, rotary floating bearings, translational fixed bearings and translational floating bearings can be configured. This depends on whether and how the limit pin is used 37 about a screw 39 in the camp 8th , 9 , 10 , 11 is fixed.

Setting up the folding table 1 from its lowered position to its erected position takes place as described below. The brake 28 locked with its brake hook 29 the gear motor 21 , whereby an adjustment of the folding table 1 tied and the folding table 1 is secured in the lowered position. The gear motor 21 starts up and carries the output torque due to the power split 35 on the brakes 28 one, causing the brake 28 releases and the lock is released. After releasing the brake 28 runs through the output torque 36 the brake 28 and can via the pinion shaft 22nd on the two pinions 23 for combing with the tooth segments 25th into the scissor mechanism 4th be entered. This moves the folding table into its set-up position. Lowering takes place in reverse order.

In order to achieve a constant and above all short travel time at high travel speed, the scissor mechanism 4th of the folding table 1 balanced in such a way that it can be adjusted by means of a drive torque that is as constant and as low as possible. This balance is achieved through the self-locking-free drive 20th on the one hand and the scissor mechanism 4th , the scenery arrangement 12th and the spring assembly 15th on the other hand. The drive designed as UNIMOT 20th includes a load torque lock, a power split, a reduction and a torque limiter.

The deployment spring 16 is designed as a leg spring and the centering springs 18th are designed as tension springs. In such an embodiment, the raising spring compensates 16 the weight of the folding table at the beginning of the erection movement. Thus, the deployment spring is used 16 overcoming the initial resistance and thus leads to a constant drive torque. The tension springs 18th in turn compensate for the weight of the folding table predominantly at the end of the erection movement. Therefore, the tension springs wear 18th also contributes to a constant drive torque. The ones in the scissor links 6th , 7th arranged backdrops 13th , 14th with the bolt guided in it 19th serve a flowing and even transition between the position of the folding table 1 , in which predominantly the opening spring 16 acts, and the position of the folding table 1 , in which predominantly the centering springs 18th works. The arrangement of the scenery 12th thus serves the evenness of the movement of the folding table 1 . The spring arrangement is designed so that it just does not hit the folding table 1 spends independently in its installation. This results in the absence of force on the folding table 1 a slight closing trend. In addition, only a small drive can 20th can be used.

A torque curve of the drive 20th while setting up the folding table 1 is in 12th pictured. In the diagram shown, the required torque is plotted against the time, whereby the specification "25 [Nm]" is only an example.

At time zero, the brake hook is at S1 29 the brake 28 with the gear motor 21 locked so that he was the folding table 1 secures in its lowered position. At this point in time, the pinion shaft is also in S2 22nd blocked. Once the gear motor 21 starts to run, the brake is applied first 28 caused lock is canceled. Due to the power split of the geared motor 21 there is no torque or output torque at this point in time 36 on the pinion shaft 22nd transfer. In other words, the folding table is moving at this time 1 not in installation. The brake only starts when the drive torque in S3 rises above the braking torque M_br 28 to release and that of the brake hook 29 to cancel the lock. At this point in time, an unlocking moment M_e is reached in S4. The unlocking torque M_e is the greatest necessary from the gear motor 21 torque to be supplied for folding table adjustment, with the brake in S5 28 completely opens. Only now can the torque or the output torque at S6 36 on the pinion shaft 22nd or the pinion 23 are transferred and into the scissor mechanism 4th of the folding table 1 be initiated. Because the brake 28 is fully open, the necessary torque in S7 drops to a travel torque M_v. When designing the folding table system, the travel torque M_v serving as the target value should be as small as possible in order to achieve the smallest possible gear motor 21 to be able to use. From S7 the brake is 28 in S8 no longer moves and the folding table 1 move into its installation position. To make an adjustment movement of the folding table 1 to end, a field can be coupled in or a Hall sensor can send a stop signal to the drive in S9 20th or send a control device, whereupon the drive in S10 20th stops and the folding table 1 keeps in its installation position.

13th shows a diagram, with the adjustment of the folding table 1 necessary force [N] compared to the percentage adjustment path [%] of the lifting table 1 is applied.

Line a shows the adjustment of the folding table 1 required force or erection force over the adjustment path. Line b shows a difference between the required erecting force and a centering spring force, which is symbolized by line e. Line c shows a pull-up spring force and line d shows an acceleration characteristic.

The course of line c shows that the opening spring 16 predominantly at the beginning of the adjustment path in the installation position on the folding table 1 acts and loses its effect as the adjustment path increases. In contrast to this is the action of the tension springs 18th low at the beginning of the adjustment path and increases with increasing adjustment path, so that the tension spring force even exceeds the opening spring force at the end of the adjustment path. The acceleration curve d shows that in the scissor links 6th , 7th arranged backdrops 13th , 14th with the bolts guided in it 19th a smooth and even transition between the position of the folding table 1 , in which predominantly the opening spring 16 acts, and the position of the folding table 1 , in which predominantly the centering springs 18th act, serve. The arrangement of the scenery 12th thus serves the evenness of the movement of the folding table 1 .

Claims (12)

Folding table, which is adjustable between a lowered position and a set-up position, comprising a cover plate (2) and a base frame (3), a scissor mechanism (4) arranged between the cover plate (2) and the base frame (3), comprising at least two pairs of scissor links (5) ) each with two scissor links (6, 7) connected to one another via a common scissor link joint, a first scissor link (6) of each pair of scissor links (5) with a first end mounted on the base frame (3) via a first bearing (8) and with its second end mounted on the cover plate (2) via a second bearing (9) and a second scissor link (7) of each pair of scissor links (5) is mounted with a first end via a third bearing (10) on the cover plate (2) and with its second end via a fourth bearing (11) is mounted on the base frame (3), a link arrangement (12) on each pair of scissor links (5) , comprising a first link (13) on the first scissor link (6) and a second link (14) on the second scissor link (7), the two links (13, 14) interacting via a bolt (19), a spring arrangement ( 15), which biases the folding table (1) in the erected position, comprising at least one centering spring (18) for each pair of scissor links (5), which is mounted with a first end on the cover plate (2) and with a second end on the bolt (19) , which forms the scissor joint, and a self-locking free ien drive (20) which is connected to a scissors member (7) in a rotationally fixed manner and adjusts the folding table (1) between the lowered position and the set-up position, the drive comprising a power-split reduction gear. Folding table after Claim 1 , characterized in that the second bearing (9) and the third bearing (10) are designed as sliding bearings and the corresponding bearing housings are fixed to the cover. Folding table after Claim 1 or 2 , characterized in that the first bearing (8) and the fourth bearing (11) are optionally adjustable between a sliding bearing and a pivot bearing, the corresponding bearing housings being fixed to the ground. Folding table according to one of the Claims 1 until 3 , characterized in that the connecting links (13, 14) are arcuate and open towards the base frame (3). Folding table according to one of the Claims 1 until 4th , characterized in that each link (13, 14) comprises a lowering position section (31) into which the bolt (19) retracts in the lowering position, and an installation section (32) into which the bolt (19) moves in the installation position . Folding table according to one of the Claims 1 until 5 , characterized in that each centering spring (18) is assigned to a scissor link (6, 7) and runs in the longitudinal direction of the corresponding scissor link (6, 7). Folding table according to one of the Claims 1 until 6th , characterized in that the drive comprises a gear motor (21) which drives a pinion shaft (22), the two ends of which are each assigned a pinion (23) and which are arranged parallel to a main shaft (24) connecting the pairs of scissor links (5) The main shaft (24) comprises at both ends a toothed segment (25) which is fixed to the main shaft and which is combed by the pinion (23), a synchronizing shaft (27) being arranged between the bearing extensions (26) of the two toothed segments (25) , which is arranged parallel to the main shaft (24) and pivotable about it. Folding table according to one of the Claims 1 until 7th , characterized in that the drive comprises a brake (28) which locks the folding table (1) in the lowered position. Folding table according to one of the Claims 1 until 8th , characterized in that the drive comprises an emergency energy store, which supplies the drive with energy as required. Folding table according to one of the Claims 7 until 9 , characterized in that the gear motor (21) and / or at least one bearing (8, 9, 10, 11) has a weather and foreign body protection according to IP67 protection class according to DIN 40050-9: 1993-05. Folding table according to one of the Claims 1 until 10 , characterized in that the spring arrangement (15) which biases the folding table (1) in the erected position further comprises: at least one erect spring (16) which acts between the cover plate (2) and the base frame (3) and at least one pair of springs (17) on each pair of scissor links (5), the pair of springs (17) being formed from two centering springs (18) and each centering spring (18) with a first end on the cover plate (2) and a second end on a bolt (19 ) is mounted, which forms the scissor link joint and extends through the aligned section of the link arrangement (12). Folding table according to one of the Claims 1 until 11 , characterized in that the raising spring (16) is designed as a leg spring and / or the centering springs (18) are each designed as a tension spring.

Images