WO2018171821A1 - Self-leveling piece of furniture and operating method - Google Patents

Abstract

The invention relates to a self-leveling piece of furniture with three or more legs, e.g. a table or chair, which, as a result of legs (3b) that can be extended or retracted individually by means of a motor and the signaling of a minimum force of each foot on the floor, does not wobble even on uneven and inclined surfaces and where inclination sensors (5) and a controller (6) additionally bring the useful surface of the piece of furniture into a horizontal or defined inclined position.

Description

description

Self-leveling furniture and operating procedures

The invention describes a self-leveling piece of furniture with three or more legs, e.g. a table or chair that stands by means of individually motorically extendable and shortenable legs even on uneven and sloping ground wobble-free and tilt sensors and a control additionally brings the furniture usable area in a horizontal or defined oblique position. Furthermore, the invention relates to a

Operating method for a self-leveling piece of furniture.

In paved terraces or rooms, on lawns or on sloping sidewalks, the floor is often uneven or even, but not level. Or the ground

changes its inclination, as with ships. In all these cases, a piece of furniture placed on it can wobble and / or its useful surface such as a

Table top is not horizontal. Thereby can

inadvertently spill liquids in glasses or soup plates or tip over glasses or bottles, or in the case of chairs on sloping surfaces, you may feel uncomfortably crooked.

In these cases, one usually tries to fix the wobbling and slanting with coasters pushed under one's feet or with other documents. To eliminate the

Wackeins is sufficient for a under one foot pushed pad, as a result of this always a wobbly three-legged

Furniture is complemented by a fourth in length fitting leg.

However, to additionally obtain, for example, a horizontal tabletop, you need up to three under

Maybe different thicknesses of documents, which must be pushed under up to three feet. This procedure is laborious, the available documents are often not the right thickness, they wear or fall in the rain and they disturb the appearance. Because of the frequent back-and-forth, the procedure in chairs is usually completely omitted because it is too annoying. The same applies to manually adjustable legs. Even more difficult to achieve wobble-free standing and a leveling in pieces of furniture with more than four legs.

Many methods are known (IPC A47B, e.g., 91 and

others), for example, to make tables wobble-free. In patent EP 1 696 765 Bl, a table includes a rigid and a moveable pair of legs intended to conform to the floor by manual reciprocation of the table. However, this does not automatically bring the tabletop as a usable area in a horizontal position.

In the utility model DE 20 2014 005 589 Ul each contains

Table foot a hydraulic cylinder with the

Hydraulic cylinders of other table feet hydraulically connected via hoses. Although this allows a wobble-free installation of the table, but also here, the tabletop as a useful surface is not automatically in a

horizontal position.

Also in patent AT 0186714 Bl must for leveling a

Multi-way valve manually placed in three different positions and the table manually adjusted two times while the table top by eye or tools are brought into the horizontal.

Also in other known devices is no

automatic leveling of floor space indicated on uneven or sloping floors.

The present invention is therefore based on the object for furniture on uneven or sloping floors both the problem of Wackeins as well as the leveling of the Use of furniture (eg table top or seat) automatically without manual action.

The object is essentially achieved in that all the legs of the furniture are adjustable in length up to at most one leg and the furniture contains a device that detects whether the foot of each leg one

Minimum force on the ground. If not, the corresponding leg is motor extended or shortened the remaining legs. The piece of furniture also contains

Tilt sensors that detect a deviation of the effective area from the horizontal and signal it to a control. The control then changes each length-adjustable leg so in length that all legs press with a minimum force on the ground and at the same time the useful surface of the piece of furniture is horizontal or predetermined oblique.

Embodiments of the invention will be explained with reference to the following figures:

Fig. 1: elements of a self-leveling table

Fig. 2: Multi-part leg with switch as a force sensor

In Fig. 1 and in the following description is as an example of a self-leveling furniture 1 a

Table presented. With the table top as a usable area 2 four legs 3a to 3d are connected, each consisting of a

fixed upper part and a sliding lower part. In this embodiment, the lower part of Fig. 2 can be moved up and down via a spindle 9 by a motor 8 within the upper part and thereby changes the length of the leg 3 with its foot 4. The motors 8 are controlled by a controller 6 , which expediently in or below the table top

is arranged and supplemented by an autonomous power supply 7 in order to operate the table at off-grid locations. To determine whether the table top is horizontal, the table also contains at least two tilt sensors 5a and 5b, which are not arranged parallel to one another and are housed in a common housing or chip according to the prior art.

The task of setting up the table wobble-free and horizontally even on uneven or sloping ground, can be done in two

Subtasks that are intertwined, namely the Entwackeln and the leveling.

Entwackeln

Will a table or other piece of furniture on the floor

As a rule, only the feet of the legs touch the ground when all the legs are exactly the same length and the ground is level. While the first condition is mostly present, the ground is not level, for example, on lawns or on paved surfaces inside and outside.

In this case, after setting up, the empty table first stands on two diagonal feet, e.g. 4a and 4d in Fig. 1. A third foot, for example 4c, will more or less strongly contact the ground if the center of gravity of the table is not exactly on the axis between the feet 4a and 4d. The fourth foot, foot 4b in this example, is then spaced from the ground. When the table top is moved back and forth, the table wobbles and feet 4b and 4c touch

alternately the ground.

To prevent shaking, it must first be determined if all four feet touch the ground. It is not enough to determine the distance to the ground. Because in practice the soil is usually something out there usually something

is compliant, even at zero distance of a foot to the ground with subsequent load on the table, the ground under the foot was slightly depressed. Then the table would wobble again. Therefore, the table is needed advantageously a device that can be used to determine whether each foot presses on the ground with a certain minimum force. The minimum force is expediently set as high as possible, but must be above the weight of the empty table above a foot, so that the table above the foot is not raised. If all four feet with this

Minimum force and less than the weight of the empty table above a foot press on the ground, neither the table is raised above a foot nor wobbles the table. In addition, since the soil compression by the foot usually increases only slightly with increasing force, it can be assumed that the vast majority of the yielding of the soil by the applied minimum force has already been done and another yielding by loads on the table the table no longer shaking.

force sensor

In one possible embodiment (FIG. 2), the

Device for detecting the minimum force described in a switch as a force sensor 15, on each foot 4 of the table. This consists in the simplest case of a

Switch housing 10 at the end of the leg 3 and a

Switch button 12, the lower end of which simultaneously forms the foot 4 of the leg 3. If the previously floating in the air leg 3 is extended or shortens the other legs, the lower end of the switch button 12 eventually touches the ground. The switch button 12 and a contact surface on its upper surface now press against the spring 11 until the two

Switching contacts 13 are bridged and thereby a signal via the electrical connections 14 to the controller 6 is formed, which in turn can turn off the corresponding motor 8 via the electrical connections 14. The too

overcoming spring force to close the switch contacts must correspond to the minimum force described.

In another advantageous embodiment, the force sensor 15 is realized without switching point. This allows the threshold, from which the minimum force is considered to be reached, be specified by software in the controller.

In a further advantageous embodiment of the

Force sensor 15, for example, between the working surface 2 and leg 3 and or between the upper and lower part of the leg 3 arranged to better protect him from moisture and shock.

current measurement

In a further embodiment, in which the drive of the legs 3 via electric motors 8, are

advantageously no force sensors needed. To the

Each leg 3 is tentatively lengthened, thereby measuring the recorded current of the associated motor 8 in the control 6. As long as the foot 4 of the leg 3 does not touch the ground, this stream is small. at

Ground contact he rises, since the engine 8 now begins, against the weight of the table over the foot 4 to

work. When the motor current reaches a value A previously determined by the manufacturer when the minimum force is reached, the controller 6 stops the motor 8, otherwise it would later start raising the table above the foot 4.

If a foot 4 is already fixed on the ground when a leg 3 is being tested, the motor current will exceed a second value previously determined by the manufacturer which corresponds to the force required to lift the table above the foot. In this case, the leg 3 is shortened again by the amount by which it was tested longer than the minimum force. This measure is determined, for example, over the life of the engine during the trial longer.

inclination measurement

In a further advantageous embodiment without

Force sensors will also test each leg 3 extended to determine if the minimum force of his foot 4 is reached on the ground. But not the motor current is measured, but the inclination of the table. It does not change as long as the foot 4 of the tentatively extended leg 3 still floats in the air and has not touched the ground, or not, as long as the table has not yet been raised after touching the bottom foot 4 and further extension of the leg 3. Only when the table is raised above the foot 4, the inclination of the table suddenly changes. This is the signal to the controller 6 that both the minimum force and the force needed to raise the table above the foot 4 have been achieved, and the controller 6 again shortens the leg by the same amount as it does over has extended the beginning of the change in inclination.

Current measurement and slope measurement can also be advantageously combined to achieve higher reliability on different soils.

The devices mentioned also work with more than four legs, so that even large boards or

Conference tables can be dangled with it.

level

A simple method of operation for a table or other furniture for combined unstacking and leveling consists, for example, of the following steps (FIG. 1):

1. Before setting up the table, all legs 3 were placed in a defined starting position, they were

For example, shortened to the stop.

 2. Place the table on a floor at the intended location.

 3. The controller 6 checks, for example by means of

Force sensors, whether at least two diagonally opposite press the feet 4 to the ground with the specified minimum force.

 4. If this is the case, the other two legs 3 are extended until their feet also reach the minimum force on the floor. The table can then no longer wobble, but still stand diagonally.

 5. Now, with the aid of that inclination sensor 5b, which is arranged for example in the longitudinal direction of the table, checked whether the table top left or right too deep

towards the horizontal or a desired inclination.

 6. The legs under the too deep transverse side are both extended simultaneously and by the same amount until the table also stands horizontally in the longitudinal direction.

 7. Since the extension of the two legs in practice is not necessarily completely synchronous, during or after step 6, the achievement of the minimum force of all legs is checked and if necessary by adjusting the

Leg length corrected.

 8. Now it is checked with the help of the other tilt sensor 5a, if the table top 2 is too low at the front or rear.

 9. The legs below the long side are extended both simultaneously and by the same amount until the table is horizontal in the transverse direction.

 10. Again, during or after step 9, the minimum force is checked and corrected if necessary.

 11. Repeat steps 3 to 10 until there is no change in inclination.

 12. The controller is placed in a stand-by mode, which only needs to be left when the table top is tilted.

 13. To ensure that the legs are not always extended each time the table is set up until they eventually stop, and the table can still be parked on a flat surface after use, they are expediently shortened again after each use , This is done, for example, when the table is off

Persons for transport is completely raised. In this Case, the inclination changes when lifting and no leg is more reaches the minimum force. Be this

Conditions are recognized, then all legs are moved back to the starting length mentioned in step 1.

An advantageous acceleration of the leveling process can be achieved by the fact that after step 4

resulting total inclination and direction of the tabletop is determined and from the required lengthening or shortening of all legs is determined and performed simultaneously in one step.

The re-adjustment of the leg lengths in the starting position can also be initiated by the leveling and use of the table by an operating element or advantageously after appropriate evaluation of the inclination sensors, that the table is raised only on one side. In the latter case no separate controls are required for this.

Likewise, a new leveling can be initiated by an operating element or advantageously by lifting the table on, for example, another side.

A further advantageous embodiment makes it possible by operating elements or lifting another page the

Place the table top in a slightly inclined position, so that, for example, raindrops can drain better before using the table.

In a further advantageous embodiment of the table after leveling by controls in his

Total height can be changed by simultaneously shortening or lengthening all legs by the same amount.

For the change in length of the legs 3 of a piece of furniture according to the invention, for example, commercially available electric linear drives can be used. These are usually provided with two switches, the complete extension and shorten the movable part until shortly before the mechanical stop the power supply for the corresponding direction of rotation of the drive motor 8 interrupt. Device now one of the legs 3 of a piece of furniture according to the invention

for example, during leveling when shortening to its stop and can not be further shortened, then instead of the remaining legs can be extended to still achieve the horizontality. For this purpose, the stop must be recognized and evaluated.

In an advantageous embodiment, this is realized without additional switches by measuring the motor current during the shortening of this leg. If it suddenly drops to zero, then the drive-internal switch has interrupted the circuit and the leg is at the stop. This information is stored in the controller until the leg is extended again in the opposite direction. Then the motor current is also measured in order to detect a possible stop and possibly to influence the direction of the leg movements.

Advantageously, during the Entwackelns and

Leveling the legs controlled so that at least one leg is shortened or extended to the stop. This optimally exploits the limited length variation of the legs on uneven or sloping ground.

additional elements

Other embodiments of the inventive furniture additionally contain elements preferably within the control with which furniture-related functions are realized. These are for example:

A navigation data receiver, which locates the

Furniture facilitates and / or can be used as anti-theft device. - Sensors that detect and report the location and number of free and occupied seats and / or chairs.

 - Building blocks and software for wireless communication that allow

 - to inventory the furniture remotely and / or

 - the piece of furniture, in particular a table in the

 Restaurant operation, clearly and / or automatically identify for the operator and / or

 - In particular with neighboring tables, which have been put together in groups, to exchange information about a jointly set surface height, and / or

- To provide software applications, by means of which in the vicinity, in particular of tables sitting guests or customers with the furniture display stand

 can communicate, for example, to place orders and / or

 - for restaurant guests and / or the operating staff

 Provide Internet access.

 - A clock that allows the furniture to be tilted and leveled at an adjustable time.

 - A rain sensor, by means of which the piece of furniture can be inclined at rain.

 - A temperature sensor for outdoor temperature detection

and / or message.

 - Charging sockets for charging mobile devices from an existing autonomous power supply.

 - A monitoring and / or reporting unit for the

Operating state of an existing autonomous energy supply of the furniture, for example, in time

be able to charge existing accumulator.

A further advantageous embodiment consists in that the motor length adjustment of the legs and the

Devices for signaling the minimum force on the floor and the controller are designed as a retrofit kit for existing furniture. Reference sign list

1 piece of furniture

 2 usable area

 3 leg

 4 feet

 5 tilt sensor

 6 control

 7 Autonomous energy supply

8 engine

 9 spindle

 10 switch housing

 11 spring

 12 switch button

 13 switching contact

 14 electrical connection

15 force sensor

Claims

claims 1. Self-leveling piece of furniture (1) with a Normally horizontal usable area (2) and thus connected three or more legs (3), with their feet (4) the piece of furniture is adjustable to a floor, characterized in that  - all legs are adjustable in length up to a maximum of one leg individually and motorized  - The furniture contains devices that signal the presence of a predetermined minimum force of each foot on the ground, and  - The furniture inclination sensors (5) containing the Measure and signal the slope of the effective area in at least two non-parallel directions, and  - The piece of furniture contains a control (6), which the adjustable legs at the place of installation of the furniture so adjusted in length, that  - All feet exercise their minimum power to the ground and at the same time  - the tilt sensors no or a desired  Signal deviation of the surface slope from the horizontal, and thus the piece of furniture does not wobble even on uneven or sloping ground and its useful area is horizontal or predeterminable obliquely. 2. Self-leveling piece of furniture according to claim 1, characterized in that the minimum force of each leg on the floor is chosen so large that the empty piece of furniture stands even with slightly deformable material of the furniture and / or slightly deformable floor with all legs firmly on the ground and does not wobble. 3. Self-leveling piece of furniture according to claim 1, characterized in that the device for determining the minimum force of a foot (4) on the ground consists of one force sensor (15) per foot, the so is arranged to measure the applied force and / or the exceeding of a threshold value of this force of the foot on the ground and to the controller (6) signals. 4. Self-leveling piece of furniture according to claim 1, characterized in that the device for detecting a minimum force of a leg on the ground in the case of electric motor operated legs is realized in that the ground contact by the incipient Raising the furniture rising current of the motor (8) is used as a signal. 5. Self-leveling piece of furniture according to claim 1, characterized in that the device for detecting a minimum force of a leg on the ground is realized by the fact that the controller length-adjustable leg on a trial basis extended further on ground contact or the remaining length-adjustable legs shortened until the inclination of the effective area changes compared to the state without ground contact of this leg, and this change is used as a signal for exceeding the minimum force, wherein the trial extension of this leg or the shortening of the remaining legs is subsequently reversed. 6. Self-leveling piece of furniture according to claim 1 or 2, characterized in that the leveled Usable by simultaneous shortening or lengthening of all adjustable legs by the same amount in their total height is adjustable or by shortening or Lengthening of adjacent adjustable legs is tilted. 7. Selbstnivellierendes piece of furniture according to claim 1 or 2, characterized in that the achievement of a stop of the length-adjustable legs when shortening or lengthening when using commercially available electric linear drives by measuring the Motor current is detected, which is interrupted in this case by switches in the linear actuators, and that the Information is used to influence the length of the other adjustable legs. 8. A self-leveling piece of furniture according to claim 1, characterized in that the piece of furniture contains an autonomous power supply (7) in order to operate the table at off-grid locations. 9. Self-leveling piece of furniture according to claim 1, characterized in that user commands to the controller or feedback from the controller via built-in furniture and / or wired or wireless controls done. 10. A self-leveling piece of furniture according to claim 1, characterized in that the controller includes: - A navigation data receiver, which facilitates finding the furniture and / or can be used as anti-theft device, and / or  - Sensors that detect and report the location and / or number of occupied table seats, and / or  - Building blocks for wireless communication that allow - to inventory the furniture remotely and - the piece of furniture, in particular a table in the  Restaurant operation, clearly and / or automatically identify for the operator and / or  - In particular with neighboring tables, which have been put together in groups, to exchange information about a jointly set surface height, and / or - To provide software applications by means of which in the vicinity, in particular guests sitting by tables or customers can communicate with the staff of the furniture setter and / or  - for restaurant guests and / or the operating staff Provide Internet access, and / or - A clock that allows tilting and horizontal positioning of the furniture at an adjustable time, and / or  - A rain sensor, by means of which the piece of furniture can be inclined at rain, and / or  - a temperature sensor for outdoor temperature detection and / or message, and / or  a monitoring and / or reporting unit for the Operating state of an existing autonomous energy supply of the piece of furniture. 11. Self-leveling furniture after one of previous claims, characterized in that the motor length adjustment of the legs and the Devices for signaling the minimum force on the floor and the controller are designed as a retrofit kit for existing furniture. 12. Operating method for a self-leveling piece of furniture (1) with a normally horizontal usable area (2) and associated three or more legs (3), with the feet (4) of which the piece of furniture can be set up on a floor, characterized in that  - all legs are adjustable in length up to a maximum of one leg individually and motorized  - The furniture contains devices that signal the presence of a predetermined minimum force of each leg on the floor, and  - The furniture inclination sensors (5) containing the Measure and signal the slope of the effective area in at least two non-parallel directions, and  - That further, the piece of furniture contains a control (6), by means of the after installation of the furniture at the installation all length-adjustable legs, for which the minimum force is not signaled to the ground, so far extended and / or the other legs are shortened that the Minimum force is achieved and the piece of furniture does not wobble, and alternately for the purpose of leveling the Nutzfläche those adjustable legs are extended, which leave the floor over the leg too low to the horizontal or the desired slope, and / or those adjustable legs are shortened, the floor over the leg are too high to the horizontal or the desired inclination until both flicker and leveling are made. 13. Operating method for a self-leveling piece of furniture according to claim 12, characterized in that for the purpose of leveling first the direction and strength of the existing inclination of the effective area of the sensor data is calculated and then the necessary different changes of all leg lengths are performed simultaneously based on the calculation results. 14. Operating method for a self-leveling piece of furniture according to claim 12, characterized in that the lifting of the furniture on one of the sides, in which case on the opposite side only two legs their Apply minimum force to the ground and the inclination of the effective area in the direction changes, as a signal is used to depending on the selected raised side a certain user-desired action such as setting a defined length of the adjustable length Legs, a re-leveling or tilting of the furniture trigger. 15. Operating method for a self-leveling piece of furniture according to claim 12, characterized in that after complete lifting of the piece of furniture, in which case no longer the predetermined minimum force on the floor for any leg is signaled and the inclination of the usable area changed compared to the user state, all adjustable legs are brought in a predetermined initial length.