EP3919770B1 - Telescopic rail - Google Patents

Description

The present invention relates to a telescopic rail with a first rail element, a second rail element, a third rail element and a drive device, the first rail element and the second rail element being mounted on one another in such a way that the first rail element and the second rail element are linear in relation to one another in and counter to an extension direction are displaceable, with the third rail element and the second rail element being mounted on one another in such a way that the third rail element and the second rail element can be linearly displaced in relation to one another in and counter to the pull-out direction, with the drive device being mounted on the first rail element or on one connected to the first rail element connectable holding element can be stored and the drive device is designed such that the drive device in an operation of the telescopic rail against a linear displacement movement of the second rail element causes enüber the first rail element in or against the pull-out direction.

Telescopic rails with two or more rail elements and a guide between each two rail elements are known in a variety of embodiments from the prior art. In many telescopic rails, the guide between two rail elements is implemented in the form of a rolling element cage. In this case, rolling elements are accommodated in the rolling element cage in order to reduce the friction between the rail elements during an extension movement. Telescopic rails are used in various household appliances, but also in automobile construction, in furniture construction and in many other applications.

US2267043A discloses a telescopic rail with a traction element.

In more and more applications, users are demanding supported or fully automated handling when operating a pull-out. Therefore, telescopic rails with a force support, for example in the form of a spring preload of one rail element relative to another, are known. In addition, motor-driven telescopic rails are known in which the displacement movement of one rail element relative to another rail element is brought about by an electric drive.

The disadvantage of such power-assisted or motor-driven telescopic rails is that they are either only available for telescopic rails with exactly two rail elements, which then necessarily form only partial extensions, or require a very high level of design complexity. The higher design effort usually also requires a larger installation space and/or higher production costs. Furthermore, the known drives require complex integration into existing constructions of the rail elements.

In contrast, the object of the present invention is to provide a telescopic rail which enables a power-assisted or motor-driven extension or retraction movement of three or more rail elements of a telescopic rail. In addition, it is an object of the invention to provide such a telescopic rail that manages with a small number of components. Furthermore, it is an object of the present invention to provide such a telescopic rail that can be manufactured inexpensively. In addition, it is an object to provide a telescopic rail that has the smallest possible installation space. Furthermore, a telescopic rail with good integrability of the drive in existing constructions of the rail elements should be created.

At least one of the aforementioned objects is achieved according to the invention by a telescopic rail with a first rail element, a second rail element, a third rail element and a drive device, the first rail element and the second rail element being mounted on one another in such a way that the first rail element and the second rail element are in and are linearly displaceable relative to one another counter to a pull-out direction, with the third rail element and the second rail element being mounted on one another in such a way that the third rail element and the second rail element are linearly displaceable relative to one another in and counter to the pull-out direction, the drive device being mounted on the first rail element or on one with the first rail element connectable holding element is storable, wherein the drive device is configured such that the drive device in an operation of the telescopic rail a linear displacement movement of the second rail element relative to the first rail element in or counter to the extension direction causes the telescopic rail to have a pulling element, the pulling element being fixed to the first rail element and to the third rail element and the pulling element being guided on the second rail element, causing a displacement movement of the second rail element relative to the first rail element leads to a displacement movement of the third rail element relative to the second rail element.

The basic idea of the present invention is to use a pulling element to couple a retraction or extension movement in or against the extension direction of the third rail element relative to the second rail element to a retraction or extension movement of the provide the second rail element with respect to the first rail element. The coupling of the two retraction or extension movements according to the invention saves space in one embodiment and is cost-effective in one embodiment.

Central to the function of the pulling element is that it is fixed both to the first rail element and to the third rail element and is also guided on the second rail element. In this way, a displacement movement of the third rail element relative to the second rail element is coupled to a displacement movement of the second rail element relative to the first rail element.

The pull-out direction in the sense of the present application denotes the possible direction of movement of a rail element relative to another rail element from a pushed-in to a pulled-out position. The pull-in movement takes place in the opposite direction to the pull-out direction.

A relative movement between two rail elements in the extension direction is referred to as an extension movement, a relative movement of two rail elements counter to the extension direction as a retraction movement.

In one embodiment of the invention, the second rail element has a first guide element with a first deflection surface and a second guide element with a second deflection surface, the first guide element being designed in such a way that the first guide element transfers a tensile force in the extension direction from the second rail element to the pulling element can be transferred, wherein the second guide element is designed in such a way that a pulling force can be transferred from the second rail element to the pulling element against the pull-out direction with the second guiding element, and wherein the pulling element is deflected by the first and second deflection surfaces in such a way that a displacement movement of the second rail element causes a transmission of a tensile force from the tension element in relation to the first rail element in or counter to the pull-out direction to the third rail element.

In one embodiment, the first deflection surface of the first guide element has a surface normal with at least one component in a direction in the extension direction and the second deflection surface of the second guide element has a surface normal with at least one component in a direction opposite to the extension direction.

In one embodiment of the invention, the first deflection surface and the second deflection surface are curved surfaces, preferably arcuate surfaces, so that when the pulling element is in contact with the deflecting surfaces, the pulling element follows the shape of the deflecting surfaces.

In one embodiment of the invention, at least the first guide element or the second guide element has a pair of opposing, mutually facing tension element guide surfaces, the tension element guide surfaces being designed in such a way that they guide the tension element in a direction perpendicular to the extension direction. The traction element guide surfaces serve to center the movement of the traction element and prevent the traction element from skipping over.

In one embodiment of the invention, at least the first or the second deflection surface is designed in such a way that it deflects the traction element by 180°, the deflection surface having a recess so that the traction element is in frictional engagement with the deflection surface over an angular range of less than 180°.

Such a design of the first or the second deflection surface or both deflection surfaces enables an effective deflection of the pulling element by 180° in each case, with the pulling element only being in frictional engagement with the respective deflecting surface over a shortened area, so that the frictional forces are reduced.

In one embodiment of the invention, the recess extends over an angular range of less than 180°, preferably 120° or less and particularly preferably 90° or less. Although it is important to make the recess as large as possible to reduce friction, effective deflection must still be ensured at the same time.

In one embodiment of the invention, the guide element is selected from a curved guide surface, a cylinder, a pin, a wheel and a roller. Guide elements such as wheels and rollers that can be pivoted or rotated relative to the second rail element reduce the frictional forces that occur.

In one embodiment of the invention, the guide elements are at a distance from one another that is at least as great as the maximum travel of the third rail element relative to the second rail element.

The tension element guide surfaces are designed in such a way that they guide the tension element in a transverse direction, ie transversely to the longitudinal extent of the tension element, in order to prevent the tension element from slipping sideways relative to the rail element. An example of a configuration of the guide element with lateral guide surfaces is the formation of a groove, the bottom of which is the respective guide surface of the guide element, so that the pulling element is also guided in the transverse direction.

In one embodiment of the invention, at least the first guide element or the second guide element has a stationary holding section fixed to the second rail element and a deflection section that can be displaced in the extension direction and fixed to the holding section, the deflection section comprising the deflection surface of the guide element and the deflection section having a The spring element is resiliently prestressed in or against the extension direction in relation to the holding section in such a way that the tension element is tensioned. In this way, the guide element can be used to prestress the pulling element. If the pulling element is pretensioned, this ensures that the telescopic rail runs without play when it is pulled out and pulled in. By changing the spring force of the spring element, the movement force that results from the wrap-around friction of the pulling element on the deflection surfaces can be changed.

In one embodiment of the invention, the holding section and the deflection section have a detent and a detent indentation, the detent and the detent indentation being designed to complement one another, the detent and the detent indentation being arranged on the holding section and the deflection section in such a way that the detent and the Detent depression form an end stop for a displacement movement of the deflection section relative to the holding section.

Such a configuration in the manner of a snap hook and the associated undercut provides a loss-prevention device for the spring-loaded guide of the pulling element in a simple manner. In particular, assembly is possible simply by inserting the deflection section into the holding section. The deflection section and the holding section then latch with one another.

In a further embodiment of the invention, the telescopic rail has two traction elements, the first guide element having two first deflection surfaces, one of the two traction elements being deflected on each of the first deflection surfaces, the second guide element having two second deflection surfaces, with each of the second deflection surfaces one of the two traction elements is deflected.

In one embodiment, the first and second guide elements are each equipped with two deflection surfaces, so that the telescopic rail can be equipped with one or two tension members, depending on the choice, for example depending on the load case to be expected.

In one embodiment of the invention, the pulling element has a latching projection on a surface that comes into frictional engagement with the deflection surface. Such a projection on the pulling element serves to interact with a recess in the respective deflection surface Detent position of the movement of the tension member relative to the deflection surfaces and thus provide a detent position of the rail elements in their movement against each other.

In one embodiment of the invention, the telescopic rail has a roller cage with roller bodies accommodated therein and guided between the running surfaces of the second rail element and the third rail element, with at least the first guide element or the second guide element forming a stop for a movement of the roller cage in or against the extension direction .

In one embodiment of the invention, the ball cage is a strip ball cage. In this way, full utilization of the installation space within the rails can be guaranteed.

In an alternative embodiment, the ball cage is a ball cage with a bridge that connects the ball cage sections between the individual running surfaces of the rail elements.

In one embodiment of the invention, the first guide element and/or the second guide element has a clearance, past which the first or the third rail element can be guided. In this way, pre-assembly of the second rail element, i.e. the middle rail, in particular with the guide elements, is possible, while in final assembly the first and third rail elements can be assembled without colliding with the guide elements.

While in principle all possible drive devices are suitable for the displacement movement of the second rail element relative to the first rail element, in one embodiment of the invention the drive device is selected from a spindle drive, a toothed belt drive, a rack and pinion drive, a flexible shaft, a push rod, a push element, a pull element, a cable pull, a gas pressure spring, a hydraulic or pneumatic cylinder and a mount for a linear motor or a combination thereof. In one embodiment of the invention, such a drive device can be coupled to an electric drive, so that the electric drive itself can be provided outside the telescopic rail.

In a further embodiment of the invention, the telescopic rail comprises an electric drive which drives the drive device, i.e. is coupled to it. This electric drive is then part of the telescopic rail. An example of a suitable electric drive is a rotary electric motor or an electromagnetic linear drive.

In one embodiment of the invention, the drive device is a spindle drive with one that is rotatable relative to the first rail element and is mounted stationary in the extension direction Threaded spindle and an internal thread fixed in the pull-out direction on the second rail element.

The internal thread can be fixed on the first or second guide element or on an additional element connected to the second rail element.

In one embodiment of the invention, the internal thread is floatingly mounted as a section of a spindle nut in at least one direction perpendicular to the pull-out direction. Such a floating mounting of the internal thread of the spindle drive in a direction perpendicular to the pull-out direction serves to compensate for the tolerance play in the interaction of the rail elements and the threaded spindle. As a result, the spindle can beat more and does not have to be guided very precisely. A further precise bearing of the end of the threaded spindle on the second rail element is omitted.

In one embodiment of the invention, the spindle nut with the internal thread is mounted in the first or the second guide element.

In one embodiment of the invention, the internal thread is floatingly mounted as a section of a spindle nut in at least one direction perpendicular to the extension direction with a spindle nut play in the first or the second guide element, wherein the threaded spindle is guided in a spindle receiving bore through the first or second guide element, wherein the Threaded spindle has a spindle play in the spindle receiving bore, the spindle play being less than or equal to the spindle nut play. In this way, beating of the threaded spindle can be reduced. A centering of the threaded spindle is made possible.

In one embodiment of the invention, the internal thread is a section of a spindle nut, with the spindle nut having a torque arm, which introduces torque transmitted from the threaded spindle to the spindle nut into the first or the second guide element.

In addition to absorbing and introducing torques, a torque arm also enables the formation of a unique assembly orientation to simplify the assembly of the telescopic rail.

In one embodiment of the invention, the spindle nut is a spring-loaded lock nut. Such a closing nut serves as overload protection. If the torque acting on the spindle nut is too great, the lock nut opens against the spring force and the rotary movement of the threaded spindle is no longer transmitted to the spindle nut.

In one embodiment of the invention, an electromagnetic spindle nut separator is provided, which clamps the threaded spindle in the de-energized state in order to provide a braking effect in this way.

In one embodiment of the invention, the second rail element has an axial bearing for the threaded spindle. In one embodiment of the invention, the bearing is designed in the form of a bearing plate bent out of the back of the rail of the first rail element. In a further embodiment, the axial bearing of the first rail element is designed as a separate plastic part which is connected to the second rail element.

In one embodiment of the invention, the pulling element is selected from a chain, a rope, a belt and a band or a combination thereof. In one embodiment of the invention, the traction element comprises an elastic or an inelastic material or a combination thereof.

In one embodiment of the invention, the pulling element is a flexible band, in particular a flexible band with a low coefficient of friction, preferably a band made of spring steel.

In one embodiment, the pulling element is designed in one piece. In one embodiment of the invention, the traction element is a one-piece endless traction element, preferably an endless belt. In a further embodiment, the pulling element is designed in one piece, but two ends of the one-piece pulling element are joined or connected to one another. In one embodiment of the invention, the ends of the pulling member are riveted or screwed together. In one embodiment of the invention, a spring return plate is used to hold the two ends of the pulling element, preferably the two ends of a strap, together. The pulling element hooks into such a spring return plate in the manner of a cable tie.

In an alternative embodiment of the invention, the tension element is designed in two parts with a first tension element section deflected around the first deflection surface and a second tension element section deflected around the second deflection surface, with the first and second tension element sections each being fixed to the first rail element and the third rail element .

A two-part tension element enables a simplified fixing or mounting of the tension element on the first and the third rail element.

In one embodiment, two fastening elements connect the first and second traction element sections to form a closed traction element. The two fastening elements are fastened to the first and third rail element, respectively. For example, ears in the fasteners are hooked into pegs on the first and third track members.

In one embodiment of the invention, the telescopic rail has at least one fastening element which is connected to the first rail element or the third rail element, with the fastening element having at least one hook, with at least one end of at least the first pull element section and one end of the second pull element section having a hanging loop , whereby the suspension loop is hooked into the hook of the fastening element. Such a design of the fastening element enables a simplified assembly of the pulling member.

A two-part pulling element also enables the pulling element to be easily provided in different lengths. On the other hand, a one-piece, closed tension element is only suitable for exactly one length of the second rail element.

It goes without saying that in one embodiment the division of the tension member into the first and second tension member sections is provided between the two fixing points on the first rail element and on the third rail element.

In one embodiment of the invention, the pulling element and/or its guide on at least the first, the second or the third rail element is designed in such a way that both pulling forces and pushing forces can be transmitted with the pulling element, with the second rail element having a guide element, with the guide element is designed in such a way that the guide element can be used to transfer both a tensile force and a shearing force from the second rail element to the pulling element, and the pulling element is deflected by the guiding element in such a way that both a pulling force acting on the pulling element and a pulling force acting on the pulling element Pushing force causes a displacement movement of the third rail element in or against the extension direction relative to the second rail element. In this embodiment, the pulling element can be designed to be open, i.e. it does not have to form a closed ring. In this way, space can be saved.

In one embodiment of the invention, the pulling member comprises or is made of an electrically conductive material. Steel and carbon fibers are examples of electrically conductive materials in this sense. In one embodiment of the invention, the pulling element consists of an electrically conductive sheet steel. Included in an embodiment of the invention the traction element is woven or knitted plastic fibers, with electrically conductive wires or fibers being woven or knitted into the woven or knitted fabric.

In one embodiment of the invention, the first and/or the second guide element also comprise at least one electrically conductive section, this electrically conductive section being electrically conductively connected to the second rail element. In a further embodiment, the traction element, which comprises or is made of the electrically conductive material, is electrically conductively connected to the first and/or the third rail element.

In this way, equipotential bonding can be provided between all three rail elements or between two selected rail elements. In addition, it is possible to provide a current and voltage supply for consumers, such as sensors and lamps, via the rail elements and the traction element.

If, within the meaning of the present application, a telescopic rail is mentioned, this term is to be understood in such a general way that not only rails are included in which the first rail element and the further rail elements have approximately the same length, but also linear guides, in which another rail element is significantly shorter than the first rail element.

If it is stated in the present application that the telescopic rail according to the invention has first, second and third rail elements, this does not exclude the telescopic rail from comprising further rail elements. In one embodiment, at least one further rail element is also synchronized with the extension movement of another rail element via the construction according to the invention with a pulling element and its guide.

In one embodiment of the invention, the first rail element of the telescopic rail is the stationary rail element which, when installed, is connected to a stationary element, for example a body of a piece of furniture. In such an embodiment, for example with a drawer, the second and the third rail element are moved relative to the stationary element.

In one embodiment of the invention, at least the first rail element or the second rail element or the third rail element is made of a material selected from a group consisting of sheet steel, aluminized sheet steel, stainless steel, aluminum and plastic. In particular, rail elements made of plastic injection molding allow the guide elements to be integrated directly into the third rail element.

In one embodiment of the invention, the first rail element has two running surfaces, the second rail element has four running surfaces and the third rail element has two running surfaces, with a plurality of rolling elements and/or sliding bodies between the two running surfaces of the first rail element and two running surfaces of the second Rail elements are arranged so that the first rail element and the second rail element can be displaced linearly in relation to one another in or counter to the extension direction, and are arranged between the two running surfaces of the third rail element and two running surfaces of the second rail element, so that the third rail element and the second rail element move in an extension direction are linearly displaceable against each other. In one embodiment of the invention, the first rail element, the second rail element and the third rail element each have legs which carry the running surfaces for the rolling bodies and a back section connecting the two legs.

Rolling elements within the meaning of the present invention can be balls or cylinders, for example. It goes without saying that in one embodiment of the invention the rolling elements are guided between the rail elements with the aid of a rolling element cage, in particular a ball cage. In one embodiment, the rolling element cage can be a split, strip-shaped cage or else a one-piece cage with a back connecting the guiding sections between opposite pairs of guiding surfaces.

Two groups of drives can be considered as the drive device for the linear displacement movement of the second rail element relative to the first rail element. On the one hand, these are drives that only provide power assistance, for example by means of a spring preload or a pneumatic element. On the other hand, drives can be considered which can be connected to an electric drive or are connected to such an electric drive, so that the extension movement and/or the retraction movement is motor-driven.

In addition, at least one of the above-mentioned objects is also achieved by a pull-out arrangement with a holding element, in particular a body, for example a piece of furniture, and a receiving element that can be moved relative to the holding element, in particular a drawer, and two telescopic rails arranged opposite one another and with parallel pull-out directions, see above as previously described in embodiments thereof, wherein the first rail element of each telescopic rail is connected to the holding element and the third rail element of each telescopic rail is connected to the receiving element.

Figur 1

ist eine schematische Seitenansicht einer Teleskopschiene gemäß einer Ausführungsform der vorliegenden Erfindung.

Figur 2

ist eine isometrische Ansicht einer Teleskopschiene gemäß einer Ausführungsform der vorliegenden Erfindung im vollständig eingezogenen Zustand.

Figur 3

ist eine teilweise weggebrochene isometrische Ansicht der Teleskopschiene aus Figur 2 im teilweise ausgezogenen Zustand.

Figur 4

ist eine isometrische Ansicht der Teleskopschiene aus den Figuren 2 und 3 im vollständig ausgezogenen Zustand.

Figur 5

ist eine teilweise weggebrochene isometrische Ansicht der Teleskopschiene aus den Figuren 2 bis 4 im vollständig ausgezogenen Zustand.

Figur 6

ist eine isometrische Ansicht einer teilweise ausgezogenen Ausführungsform einer Teleskopschiene gemäß einer weiteren Ausführungsform der vorliegenden Erfindung.

Figur 7

ist eine teilweise weggebrochenen, vergrößerte isometrische Ansicht des ersten Führungselements der Teleskopschiene aus Figur 6.

Figur 8

ist eine teilweise weggebrochenen, vergrößerte Draufsicht auf das erste Führungselement aus Figur 7.

Figur 9

ist eine teilweise weggebrochenen, vergrößerte Teilschnittansicht des ersten Führungselements aus Figuren 7 und 8.

Figur 10

ist eine teilweise weggebrochenen, vergrößerte Teilschnittansicht des zweiten Führungselements der Teleskopschiene aus den Figuren 6 bis 9.

Figur 11

ist eine teilweise weggebrochenen, vergrößerte Seitenansicht der Lagerung der Gewindespindel der Teleskopschiene aus den Figuren 6 bis 10.

Figur 12

ist eine Schnittansicht der Teleskopschiene aus Figur 6 im Bereich der Spindelmutter.

Figur 13

ist eine teilweise weggebrochene Schnittansicht der Teleskopschiene aus Figur 6 im Bereich des ersten Führungselements.

Figur 14

ist eine teilweise weggebrochene Schnittansicht einer alternativen Ausführungsform des Zugorgans.

Further advantages, features and possible applications of the present invention become clear from the following description of an embodiment and the associated figures. In the figures, the same elements are denoted by the same reference symbols.

figure 1

12 is a schematic side view of a telescopic rail according to an embodiment of the present invention.

figure 2

12 is an isometric view of a telescoping slide according to an embodiment of the present invention in the fully retracted condition.

figure 3

13 is a partially broken away isometric view of the telescoping rail figure 2 in partially extended condition.

figure 4

is an isometric view of the telescoping slide of FIGS Figures 2 and 3 in fully extended condition.

figure 5

13 is an isometric view, partially broken away, of the telescoping rail of FIGS Figures 2 to 4 in fully extended condition.

figure 6

13 is an isometric view of a partially exploded embodiment of a telescoping slide according to another embodiment of the present invention.

figure 7

13 is an enlarged isometric view, partially broken away, of the first guide member of the telescoping slide figure 6 .

figure 8

12 is a partially broken, enlarged plan view of the first guide member figure 7 .

figure 9

13 is a partially broken, enlarged, partial sectional view of the first guide member Figures 7 and 8 .

figure 10

12 is a partially broken, enlarged, partial sectional view of the second guide member of the telescopic rail of FIGS Figures 6 to 9 .

figure 11

13 is a partially broken-away, enlarged side view of the bearing of the threaded spindle of the telescopic rail of FIGS Figures 6 to 10 .

figure 12

12 is a sectional view of the telescopic rail figure 6 in the area of the spindle nut.

figure 13

Fig. 13 is a partially broken sectional view of the telescopic rail of Fig figure 6 in the area of the first guide element.

figure 14

Figure 12 is a partially broken-away sectional view of an alternative embodiment of the pull member.

Figures 15a and 15b show an embodiment of a two-part traction element.

The telescopic rails 4 discussed below with reference to the illustrations from the figures all have exactly three rail elements, namely a first rail element 1, a second rail element 2 and a third rail element 3. In these embodiments, the first rail element 1 forms an outer rail and the second rail element one Center rail and the third rail element 3 an inner rail of the telescopic rail 4.

The considered embodiments of the telescopic rail 4 are full extensions, i.e. the third rail element 3 can be extended to its full length compared to the first rail element 1, so that it no longer has an overlap with the first rail element 1 in the extension direction 7. In the illustrated embodiments, the first rail element 1 is a fixed rail element, for example connected to a body of a piece of furniture.

The rail elements 1, 2, 3 are slidably mounted on one another in pairs. The second rail element 2 is slidably mounted on the first rail element 1 and the third rail element 3 is slidably mounted on the second rail element 2 .

In the illustrated embodiment, the middle rail element 2 consists of two rails which are connected to one another in a materially bonded manner at the back and each have two running surfaces.

The schematic diagram figure 1 makes it possible to illustrate the principle of coupling a displacement movement of the second rail element 2 relative to the first rail element 1 to a displacement movement of the third rail element 3 relative to the second rail element 2 on which the invention is based.

For the following considerations, it is initially irrelevant how the second rail element 2 is moved relative to the first rail element 1, in particular how a Drive of the second rail element 2 is configured for a displacement movement of this rail element 2 relative to the first rail element 1 .

The coupling between the two displacement movements takes place via a pulling element, in the embodiment shown via a nylon strip 5 which is elastic in the transverse direction. This elastic band 5 is fixed to the front end of the first rail element 1 in the pull-out direction 7 with the aid of a rivet 6 . In addition, the strap 5 is also fixed with a rivet 8 at the rear end of the third rail element 3 in the pull-out direction 7 .

The band 5 is now additionally guided around two guide elements in the form of a first pin 10 and a second pin 9 which are provided in a stationary manner on the second rail element 2 . In the context of the present application, the first pin 10 forms a first guide element and the second pin 9 forms a second guide element. If the second rail element 2 is now moved in the extension direction 7 relative to the first rail element 1, the first pin 10 presses the strap 5 in the extension direction 7 and thus exerts a tensile force on the strap 5 and the rivet 8 on the third rail element 3. so that the third rail element 3 is also displaced in the pull-out direction 7 in relation to the second rail element 2 .

When the second rail element 2 moves in the pull-out direction, a first section 11 of the strap 5, which extends from the rivet 6 on the first rail element via the first pin 10 to the rivet 8 on the third rail element 3, forms a load strand 11. A second section of the band 5, which extends from the rivet 6 on the first rail element 1 via the second pin 9 to the rivet 8 on the third rail element 3, forms a slack side in this direction of movement. If the direction of movement of the second rail element 2 is reversed so that it moves in the opposite direction to the extension direction 7 relative to the first rail element 1, the tight strand 11 becomes the slack strand and the slack strand 12 becomes the tight strand.

When the second rail element 2 is moved in the extension direction 7 , the first pin 10 acts like a loose roller, with the “loose end” of the strap 5 pulling the third rail element 3 in the extension direction 7 . If the direction of movement is reversed, this consideration applies to the second pin 9.

the Figures 3 to 5 now show isometric views of a telescopic rail 4, which previously based on the scheme figure 1 described construction principle realized.

In this embodiment, the middle rail 2 can be moved in and against the pull-out direction 7 with respect to the first rail element 1 by means of a spindle drive 13 driven by a motor. The threaded spindle of the spindle drive 13 is mounted on the first rail element 1 and engages in a spindle nut fixed on the second rail element 2, so that when the spindle rotates, the second rail element slides relative to the first rail element. In the illustrated embodiment, the spindle nut is fixed to the second rail element in and counter to the pull-out direction 7, but floating in the transverse direction perpendicular to the pull-out direction 7, i.e. with play, in order to be able to accommodate tolerances in the transverse direction. The spindle in turn is coupled to an electric motor 14 so that the extension and retraction movement of the telescopic rail 4 is motor-driven.

In the illustrations from Figures 4 and 5 the telescopic rail 4 is shown placed on the first rail element 1, with the in Figures 3 and 4 upper part of the telescopic rail 4 is shown broken away. It is thus possible to look inside the second rail element 2 .

Inside, a nylon band can be seen as the pulling element 5, which is fixed at the points designated by the reference numerals 15 and 16 on the first 1 and third 3 rail element. If the spindle drive 13 now moves the second rail element 2 in the extension direction 7, this displacement movement leads to a train on the belt 5, so that the third rail element 3 is also displaced relative to the second rail element 2 in the extension direction.

In particular figure 5 the two guide elements 17, 18 arranged on the second rail element 2 can be seen. Like the pins 9, 10, these deflect their function previously for the scheme figure 1 described, the band-shaped pulling element 5 around and support the pulling element 5 in a direction parallel to the extension direction 7. In this way, forces acting on the second rail element 2 in a direction parallel to the pulling-out direction 7 can be transmitted to the pulling element 5.

the Figures 6 to 13 show various aspects of a further embodiment of the telescopic rail 4. This telescopic rail 4 also consists of a first stationary rail element 1, a second, central rail element 2 and a third rail element 3. The three rail elements 1, 2, 3 form a full extension.

In this embodiment, too, an extension or retraction movement of the second rail element 2 relative to the first rail element 1 is driven with the aid of a spindle drive 13. The spindle drive 13 comprises a threaded spindle 19, a spindle nut 20 and a Electric motor 14 includes. The extension and retraction movement of the third rail element 3 synchronized with the extension and retraction movement of the second rail element 2 relative to the first rail element 1 takes place, as in the previously described embodiments, with the aid of a belt 5 as a pulling element.

To guide the tape 5 also includes the embodiment of the telescopic rail 4 from Figures 6-13 two guide elements 17, 18. The first guide element 17 is in the Figures 7-9 shown enlarged. As in the Figures 7 and 8 As can be seen, the first guide element 17 has two first deflection surfaces 21, 22. In this way, two pulling elements can be guided with the first guide element in order to adapt the telescopic rail 4 to different load cases. In the embodiment shown, only one band 5 is attached to the two guide elements 17, 18 for synchronizing the pull-out or Collection movement of the third rail element 3 was added.

In the representations of Figures 7 and 8 it can be seen that the band 5 is guided on the first guide element 17 in addition to the deflection surface 22 also laterally with the aid of two traction element guide surfaces 23, 24 pointing towards one another. These lateral tension element guide surfaces 23, 24 prevent the belt 5 from jumping over or off the respective deflection surface 21, 22. In addition, the tension element guide surfaces 23, 24 center the movement of the belt 5 on the respective deflection surface 21, 22.

Each of the deflection surfaces 21, 22 causes the belt 5 to be deflected by 180°, 180° being the angle of wrap of the belt. However, the deflection surfaces 21, 22 each have two recesses 25, 26. These recesses 25, 26 reduce the contact surface of the band 5 on the respective deflection surface 21, 22, so that the friction between the band 5 and the respective deflection surface 22 is reduced. The recesses 25, 26 shown each extend over an angular range of less than 90°.

The recesses 25, 26 can also provide a latching function, as is shown schematically in figure 14 is shown. In this variant, the pulling element 5 has a latching projection 27 on its inner surface 28 . This latching projection engages in one of the recesses 25, 26 when it reaches it and positions the strap 5 and thus the extension movement of the third rail element 3 relative to the second rail element 2 at a position predetermined by the position of the latching projection 27 on the strap 5.

It goes without saying that the second guide element 18 is designed in accordance with the first guide element 17 . The second guide element 18 also has two deflection surfaces 21, 22, which also cause a deflection of the tension member 5 by 180 °. This is from the sectional view of the figure 10 to recognize.

In the embodiment shown, the second guide element 18 is designed in two parts. The guide element 18 comprises a holding section 29 and a deflection section. The holding section 29 is connected in a stationary manner to the second rail element 2, while the deflection section 30 is mounted on the holding section 29 so that it can be displaced in the pull-out direction. The deflection section 30 carries the deflection surfaces 21, 22. A spiral spring 31 as a spring element within the meaning of the present application prestresses the deflection section 30 in the extension direction 7 in a resilient manner. In this way, the tension member 5 is held taut by the spring 31 under tension. This reduces the play of the pulling element 5 in relation to the three rail elements 1, 2, 3 and thus reduces the play of the extension movements of the rail elements relative to one another. The movement of the deflection section 30 under pretension is limited by a stop surface 32 on the holding section 29, the deflection section 30 having a hook 33 which is designed in such a way that it engages with the stop surface 32 and strikes there. The combination of stop surface 32 and hook 33 is also used for easy assembly of the deflection section on the holding section. The deflection section 30 is pushed onto the holding section 29 and latches as soon as the axial position of the hook 33 has passed the stop surfaces 32 .

In the illustrated embodiment, a rolling element cage 34 in the form of a strip ball cage 34 is provided between two rail elements 1, 2, 3 in each case. The first guide element 17 also forms a stop for two strip ball cages 34 which are arranged between the second rail element 2 and the third rail element 3 .

Furthermore, the first guide element 17 is also used to mount the spindle nut 20 on the second rail element 2. This reduces the number of necessary components and connections to the second rail element 2. The spindle nut 20 has an internal thread 38 which engages with the threaded spindle 19. The spindle nut 20 is accommodated in the first guide element 17 in such a way that it is fixed in and counter to the pull-out direction in such a way that a rotational movement of the threaded spindle 19, which is stationarily mounted on the first rail element, results in a linear movement of the spindle nut 20 and thus of the second rail element 2 in relation to the first rail element 1 leads.

In contrast, the spindle nut 20 is mounted floating on the first guide element 17 in all directions perpendicular to the pull-out direction 7 . So hitting the threaded spindle 19 is compensated for against the rail elements and does not lead to vibration of the Rail elements 1, 2, 3. figure 12 shows the mounting of the threaded spindle 20 in the first guide element 17 in a cross-sectional view. Viewed in this view, the spindle nut 20 is mounted in a floating manner both in a vertical direction 36 and in a transverse direction 37 .

The spindle nut 20 is also designed in such a way that it has torque supports in the form of projections 39 on two sides. These direct the torques, which are transmitted from the threaded spindle 19 to the spindle nut 20 , into the first guide element 17 . Thus, the torques do not have to be transmitted exclusively via the side surfaces 40 of the spindle nut. The rail can therefore also be used for higher load cases.

The projections 39 not only serve to form torque supports, but also provide an unambiguous assembly orientation, which prevents the spindle nut 20 from being assembled incorrectly.

In figure 7 it can be seen that the threaded spindle 19 is guided through the first guide element 17 through a spindle receiving bore 41 in order to engage with the spindle nut 20 . The spindle mounting hole 41 is dimensioned such that the play of the threaded spindle 19 in the spindle mounting hole 41 is smaller than the play of the spindle nut 20 in the vertical direction 36 and the transverse direction 37.

figure 10 shows the mounting of the end of the threaded spindle 19 on the motor side on the first rail element 1. This mounting takes place in the axial direction, i.e. in the direction of the extension direction, with the aid of a bracket 42 bent off the back of the rail 42 of the first rail element 1, with a hollow cylindrical bearing bush in this bracket 42 43 is added to guide the spindle 19.

figure 13 1 shows that the guide element 17 has a clearance 44 which enables the third rail element 3 to be fitted to the second rail element 2 already equipped with the guide elements, without the third rail element 3 colliding with the guide element 17 .

Figures 15a and 15b show a two-part configuration of a band-shaped pulling element 5, the two pulling element sections 44, 45 being connected to one another at both of their ends. A fastening element 46 with two hooks 47 serves as a connector for the ends. The fastener 46 also has a bore through which a rivet is driven in order to connect the fastening element 46 to the first rail element 1 or the third rail element 3 .

Reference List

1

first rail element

2

second rail element

3

third rail element

4

telescopic rail

5

Band as a pulling element

6.8

rivet

7

pull direction

9, 10

Pen

11

load strand

12

slack side

13

spindle drive

14

electric motor

15

Fixing point of the band 5 on the first rail element 1

16

Fixing point of the band 5 on the third rail element 3

17, 18

guide element

19

lead screw

20

spindle nut

21, 22

deflection surface

23, 24

Tension member guide surfaces

25, 26

recess

27

Snap-in projection of the pulling element 5

28

Inner surface of the traction element 5

29

holding section

30

deflection section

31

spiral spring

32

stop surface

33

hook

34

Stripe Ball Cage

35

attack

36

vertical direction

37

transverse direction

38

inner thread

39

head Start

40

side surface of the spindle nut

41

Spindle mounting hole

42

Tab for guiding the threaded spindle

43

bearing bush

44.45

tension member section

46

fastener

47

hook

48

hanging loop

Claims (15)

1. Telescopic rail (4) comprising

   a first rail element (1),

   a second rail element (2),

   a third rail element (3) and

   a drive device (13),

   wherein the first rail element (1) and the second rail element (2) are mounted against one another such that the first rail element (1) and the second rail element (2) can be moved linearly relative to one another in and counter to a pull-out direction (7), wherein the third rail element (3) and the second rail element (2) are mounted against one another such that the third rail element (3) and the second rail element (2) can be moved linearly relative to one another in and counter to the pull-out direction (7), wherein the drive device (13) is mounted on the first rail element (1) or can be mounted on a holding element which can be connected to the first rail element and wherein the drive device (13) is configured such that the drive device (13) can produce a linear displacement movement of the second rail element (2) relative to the first rail element (1) in or counter to the pull-out direction (7) during the operation of the telescopic rail (4),

   characterised in that

   the telescopic rail (4) comprises a traction element (5),

   wherein the traction element (5) is fixed to the first rail element (1) and to the third rail element (3), and

   wherein the traction element (5) is guided on the second rail element (2) in a direction parallel to the pull-out direction (7) such that a displacement movement of the second rail element (2) relative to the first rail element (1) leads to a displacement movement of the third rail element (3) relative to the second rail element (2).
2. Telescopic rail (4) according to the preceding claim, characterised in that the second rail element (2) comprises a first guide element (10, 18) having a first deflection surface (21, 22) and a second guide element (9, 17) having a second deflection surface (21, 22),

   wherein the first guide element (10, 18) is configured such that a pulling force in the pull-out direction (7) can be transmitted from the second rail element (2) to the traction element (5) by means of the first guide element (10, 18),

   wherein the second guide element (9, 17) is configured such that a pulling force counter to the pull-out direction (7) can be transmitted from the second rail element (2) to the traction element (5) by means of the second guide element (9, 17), and wherein the traction element (5) is deflected by the first and second deflection surfaces (21, 22) such that a displacement movement of the second rail element (2) relative to the first rail element (1) causes a pulling force to be transmitted from the traction element (5) in or counter to the pull-out direction to the third rail element (3).
3. Telescopic rail (4) according to the preceding claim, characterised in that at least the first guide element (10, 18) or the second guide element (9, 17) comprises a pair of oppositely disposed traction element guide surfaces (23, 24) which face one another, wherein the traction element guide surfaces (23, 24) are configured such that they guide the traction element (5) in a direction perpendicular to the pull-out direction (7).
4. Telescopic rail (4) according to Claim 2 or 3, characterised in that at least the first guide element (10, 18) or the second guide element (9, 17) comprises a stationary holding section (29) which is fixed to the second rail element (2) and a deflection section (30) which is fixed to the holding section (29) such that it can be moved in the pull-out direction (7), wherein the deflection section (30) comprises the deflection surface (21, 22) of the guide element (9, 17) and wherein the deflection section (30) is resiliently pretensioned relative to the holding section (29) in or counter to the pull-out direction (7) by means of a spring element (31) such that the traction element (5) is tensioned.
5. Telescopic rail (4) according to any one of Claims 2 to 4, characterised in that at least the first or the second deflection surface (21, 22) is configured such that it deflects the traction element by 180°, wherein the deflection surface (21, 22) comprises a recess (25, 26), so that the traction element (5) is in frictional engagement with the deflection surface (21, 22) over an angular range of less than 180°.
6. Telescopic rail (4) according to the preceding claim, characterised in that the traction element (5) comprises a latching projection (27) on a surface (28) which comes into frictional engagement with the deflection surface (21, 22).
7. Telescopic rail (4) according to any one of Claims 2 to 6, characterised in that the telescopic rail (4) comprises a rolling element cage in which rolling elements guided between the running surfaces of the second rail element (2) and the third rail element (3) are accommodated, wherein at least the first guide element (1) or the second guide element (2) forms a stop (35) for a movement of the rolling element cage (34) in or counter to the pull-out direction (7).
8. Telescopic rail (4) according to any one of the preceding claims, characterised in that the drive device (13) is a spindle drive (13) comprising a threaded spindle (19) which is rotatable relative to the first rail element (1) and is stationarily mounted in the pull-out direction (7) and an internal thread (38) which is fixed on the second rail element (1) in the pull-out direction (7), wherein the internal thread (38) is preferably mounted as a portion of a spindle nut (20) such that it floats in at least one direction perpendicular to the pull-out direction (7).
9. Telescopic rail (4) according to Claim 8, characterised in that the internal thread (38) is mounted as a portion of a spindle nut (20) in the first or second guide element (1, 2) such that it floats in at least one direction perpendicular to the pull-out direction (7) with a nut clearance, wherein the threaded spindle (19) is guided through the guide element (17, 18) in a spindle receiving bore (41), wherein the threaded spindle (19) in the spindle receiving bore (41) has a spindle clearance and wherein the spindle clearance is less than or equal to the nut clearance.
10. Telescopic rail (4) according to Claim 8 or 9, characterised in that the internal thread (38) is a section of a spindle nut (20), wherein the spindle nut (20) comprises a torque arm (41) which introduces torque transmitted from the threaded spindle (19) to the spindle nut (20) into the first or second guide element (17, 18).
11. Telescopic rail (4) according to any one of Claims 8 to 10, characterised in that the spindle nut (20) is a clasp nut as overload protection.
12. Telescopic rail (4) according to any one of Claims 2 to 11, characterised in that the traction element (5) is configured in two parts with a first traction element section (11) guided around the first guide element (10, 18) and a second traction element section (12) guided around the second guide element (9, 17), wherein the first and the second traction element section (11, 12) are respectively fixed on the first rail element (1) and the third rail element (3).
13. Telescopic rail (4) according to any one of the preceding claims, characterised in that the second rail element (2) comprises an axial bearing for the threaded spindle (19), wherein the axial bearing preferably comprises a bearing plate (42) bent out of a rail back of the first rail element (1).
14. Telescopic rail (4) according to any one of the preceding claims, characterised in that the traction element (5) is configured such that both pulling forces and pushing forces can be transmitted by means of the traction element (5), wherein the second rail element (2) comprises a guide element (17, 18), wherein the guide element (17, 18) is configured such that a pulling force and a pushing force can be transmitted from the second rail element (2) to the traction element (5) by means of the guide element (17, 18), and wherein the traction element (5) is deflected by the guide element (17, 18) such that both a pulling force acting on the traction element (5) and a pushing force acting on the traction element (5) causes a displacement movement of the third rail element (3) in or counter to the pull-out direction (7) relative to the second rail element (2).
15. Pull-out assembly comprising a holding element, in particular a cabinet, and a receiving element, in particular a drawer, which can be moved relative to the holding element, and two telescopic rails (4) which are disposed opposite to one another and with parallel pull-out directions (7) according to any one of the preceding claims, wherein the first rail element (1) of each telescopic rail (4) is connected to the holding element and the third rail element (3) of each telescopic rail (4) is connected to the receiving element.

Images