Two-way pull-out rail

Abstract

The present invention relates to a two-way pull-out rail which has a first rail element (1) with a first end and a second end, and a second rail element (2), wherein the first rail element and the second rail element can be linearly displaced against one another along a pull-out axis (5) between a first pull-out position and a second pull-out position. According to the invention, the first rail element or a first component, which is connected to the first rail element and is unmovable with respect to the first rail element along the pull-out axis, has a first entraining portion (10) and a second entraining portion (11), wherein the first entraining portion and the second entraining portion are spaced apart from one another along the pull-out axis. The second rail element or a second component, which is connected to the second rail element and is unmovable with respect to the second rail element along the pull-out axis, has a drive unit (9) which rotates with respect to the second rail element. The first entraining portion and the second entraining portion can be coupled to the drive unit, such that a positive fit or friction fit is formed, and can be decoupled. Furthermore, the first entraining portion, the second entraining portion and the drive unit are arranged and designed such that in a first pull-out position, the first entraining portion and the drive unit are decoupled and the second entraining portion and the drive unit are coupled, and that in a second pull-out position the first entraining portion and the drive unit are coupled and the second entraining portion and the drive unit are decoupled.

Description

[0001] Two-way pull-out rail

[0002] The present invention relates to a pull-out rail comprising a first rail element with a first end and a second end and a second rail element, wherein the first rail element and the second rail element are linearly displaceable relative to one another along a pull-out axis between a first pull-out position and a second pull-out position, and wherein in the first pull-out position the first end of the first rail element lies in the axial direction outside the second rail element and in the second pull-out position the second end of the first rail element lies in the axial direction outside the second rail element.

[0003] Such a pull-out rail of the aforementioned type defines a so-called two-way pull-out rail. Various variants of such two-way pull-out rails are known from the prior art. Two-way pull-out rails allow a movable or mobile rail element to be pulled out relative to a stationary rail element from a zero position (usually the fully retracted state) in two opposing axial first and second pull-out directions, whereby no stop is provided to define the zero position and prevent a pull-out movement in one of the pull-out directions. Two-way pull-out rails can be used, for example, to pull out a drawer from two sides of an emergency vehicle.

[0004] Two-way pull-out rails with an electric drive require complex drive trains due to the bidirectional extension. Furthermore, two-way pull-out rails with three or more rail elements that provide full or over-extension with synchronized extension movements of the rail elements relative to each other are not known in the prior art.

[0005] The present invention is therefore based on the object of providing a two-way pull-out rail which, in a simple manner, enables at least one electric drive of an at least two-part pull-out rail or a synchronization of more than two rail elements relative to one another during the pull-out movement in both pull-out directions.

[0006] At least one of the aforementioned objects is achieved by a pull-out rail according to the appended independent claim. To this end, in a pull-out rail of the type mentioned at the outset, the first rail element or a first component connected to the first rail element and immovable relative to the first rail element along the pull-out axis has a first driving section and a second driving section, wherein the first driving section and the second driving section are spaced apart from one another along the pull-out axis. According to the invention, the second rail element or a second component connected to the second rail element and immovable relative to the second rail element along the pull-out axis has a drive unit rotating relative to the second rail element.The first driving section and the second driving section can be coupled to the drive unit, forming a positive or frictional connection, and can be uncoupled. Furthermore, the first driving section, the second driving section, and the drive unit are arranged and configured such that, in the first extended position, the first driving section and the drive unit are uncoupled and the second driving section and the drive unit are coupled, and that, in the second extended position, the first driving section and the drive unit are coupled and the second driving section and the drive unit are uncoupled.

[0007] The idea underlying the present invention is to provide a two-way extension rail in which, depending on the extension direction in which the second rail element is moved relative to the first rail element, one of the two driving sections is always coupled to the drive unit, while the other driving section is uncoupled. Thus, rotation of the drive unit always leads to a linear movement of the first and second rail elements relative to one another, and optionally also of a third rail element and the second rail element relative to one another.

[0008] The first and second driving sections are both coupled to the drive unit only in a zero position and optionally in an area around this. The zero position is the position of the first and second rail elements, and optionally of the second and a third rail element, relative to one another from which the extension movements begin in a first extension direction and in a second extension direction opposite to the first extension direction. In one embodiment, the zero position is reached when the extension rail is fully retracted, in which the first and second rail elements, and optionally the third rail element and the second rail element, overlap to the maximum extent along the extension axis.

[0009] A two-way pull-out rail is characterized in that, in the first pull-out position, the first end of the first rail element protrudes beyond a first end of the second rail element when viewed in the axial direction. In other words, in the first pull-out position, the first end of the first rail element does not overlap with the second rail element when viewed in a direction perpendicular to the pull-out axis. In the second pull-out position, the second end of the first rail element protrudes beyond a second end of the second rail element. In other words, in the second pull-out position, the second end of the first rail element does not overlap with the second rail element when viewed in a direction perpendicular to the pull-out axis.This is equivalent to the wording in independent claim 1, according to which in the first extension position the first end of the first rail element lies in the axial direction outside the second rail element and in the second extension position the second end of the first rail element lies in the axial direction outside the second rail element.

[0010] When viewing the pull-out rail with the first and second rail elements in a fully inserted state, the first end of the first rail element and the first end of the second rail element are located on the same side of the pull-out rail in the axial direction, viewed from the center of the pull-out rail. Likewise, viewed from the center of the pull-out rail, the second end of the first rail element and the second end of the second rail element are located on the same side of the pull-out rail in the axial direction.

[0011] The extension axis defines an axis to which the opposite first and second extension directions of the two-way extension rail are parallel.

[0012] In one embodiment of the invention, the first and second rail elements are mounted directly against one another such that the first and second rail elements are linearly displaceable relative to one another along the extension axis between the first extension position and the second extension position. In one embodiment, rolling elements are arranged between the running surfaces of the first rail element and the running surfaces of the second rail element. The rolling elements, in particular bearing balls, roll between these running surfaces and reduce the friction between the first and second rail elements during the linear movement.

[0013] In one embodiment of the invention, the first extension position and the second extension position are the end positions of the extension movements of the two rail elements relative to each other in the opposite first and second extension directions parallel to the extension axis.

[0014] In one embodiment of the invention, the first rail element is the stationary rail element of the two-way pull-out rail, while the second rail element forms the mobile rail element. Such an embodiment is particularly useful when the pull-out rail additionally has a third rail element that is linearly displaceable relative to the second rail element.

[0015] The decoupling of a driving section from the drive unit occurs by disengaging the two elements. If the drive unit comprises a drive belt or a drive chain, decoupling occurs when the section of the drive belt or drive chain with which the driving section is engaged reaches a deflection point of the drive belt or drive chain. If the drive unit comprises a first and a second drive wheel, decoupling occurs when the driving section disengages from the respective drive wheel. It is understood that then typically another driving section of the driving element engages with the drive wheel.

[0016] In one variant, the first rail element comprises both the first carrier section and the second carrier section. These are spaced apart from each other such that, in the first extension position, the first carrier section and the drive unit are uncoupled and the second carrier section and the drive unit are coupled. In the second extension position, the first carrier section and the drive unit are coupled and the second carrier section and the drive unit are uncoupled.

[0017] In an alternative variant, however, only the first driving section is arranged on the first rail element itself, with the second driving section being arranged on a first component that is immovable relative to the first rail element along the pull-out axis. What is crucial is that the second driving section moves completely synchronously with the first rail element. An example of such a variant is a pair of first and second pull-out rails according to the present invention that are connected via a moving element, for example a drawer. In this case, for example, the first driving section is provided on the first rail element of the first pull-out rail and the second driving section is provided on the first rail element of the second pull-out rail.

[0018] Common to all variants and embodiments is that the drive unit, which rotates relative to the second rail element, and the first driving section or the second driving section can be coupled and uncoupled from one another. In the coupled state, axial forces are transmitted from the respective driving section to the drive unit, but not in the uncoupled state.

[0019] There are numerous variants for implementing such a clutch concept. In one embodiment, a clutch is provided solely by a frictional connection between a surface of the respective driving section and a friction belt, e.g., a rubber friction belt.

[0020] In one embodiment of the invention, the drive unit on the second rail element comprises a drive belt or a drive chain, wherein two deflection elements guiding the drive belt or the drive chain are provided on the second rail element, and wherein the first and the second driving section are each at least one friction surface section or a form-fitting section. A friction surface section is a surface of the driving section of the first rail element which is driven by the rotating drive belt or the rotating drive chain during a corresponding rotational movement of the drive belt or the drive chain due to the acting frictional forces. In contrast, the driving of the form-fitting section with the rotating drive belt or the rotating drive chain is primarily based on a form-fitting connection between the drive belt or the drive chain in a direction parallel to the extension axis.

[0021] If the driving sections are realized as first and second form-locking sections and these form-locking sections each have a plurality of teeth with the same pitch, the first and the second form-locking section must be spaced from each other such that the distance between the two teeth of the first and the second form-locking section that are closest to each other is a multiple of the pitch of the teeth of the first and the second driving section.

[0022] Examples of drive belts based on frictional engagement include flat belts, V-belts, and round belts. Examples of drive belts based on positive engagement with the corresponding positive engagement section include timing belts and flat belts with holes. A drive chain also uses positive engagement. A driving effect between the drive belt / drive chain and the corresponding driving section based on a combination of frictional engagement and positive engagement is also conceivable.

[0023] Examples of pairings between drive belt / drive chain and drive section include:

[0024] - Flat belt with holes and driving section in the form of a bolt

[0025] - Drive chain and driving section with teeth that engage with the drive chain (a kind of rack)

[0026] - Drive belt / drive chain in the form of a rope with spaced-apart beads, the driving section enclosing the beads.

[0027] For a positive connection between the driving section and the drive belt / drive chain, it is advisable if the positive connection acts in both directions parallel to the extension axis.

[0028] In one embodiment, at least one of the deflection elements is a pulley rotatably mounted on the second rail element. Preferably, both deflection elements are pulleys rotatable relative to the second rail element. Such a pulley is, for example, a toothed belt pulley.

[0029] In one embodiment of the invention, the drive belt is a double toothed belt with teeth on an outer side and with teeth on an inner side, wherein the first driving section is a first positive locking section and the second driving section is a second positive locking section, wherein the first and the second positive locking section can be brought into engagement (ie coupled) with the teeth on the outer side of the double toothed belt, wherein at least one of the two deflection elements is a toothed belt pulley and wherein the toothed belt pulley meshes with the teeth on the inner side of the double toothed belt.

[0030] In one embodiment of the invention, the positive engagement section is a single projection or tooth that can be brought into engagement with the teeth on the outside of the double toothed belt. In one embodiment, at least one of the first positive engagement section and the second positive engagement section is a rack section. In a further embodiment, the first and second positive engagement sections are spaced-apart sections of a single, continuous rack. In an embodiment in which the drive unit comprises a drive belt or a drive chain, the first and second entraining sections are limited to a first and a second position on the first rail element along the extension axis, since the drive belt extends over the second rail element along the extension axis.In contrast, in the embodiment described below, with a first and a second drive wheel, it is necessary for the first and second drive sections to be sections of a drive element extending axially along the first rail element. In this way, a section of the drive element is always engaged with one of the two drive wheels. Only in the zero position is the drive element engaged with both drive wheels.

[0031] Therefore, in an alternative embodiment of the invention, the drive unit comprises a first drive wheel and a second drive wheel, wherein the first driving section and the second driving section are spaced-apart sections of a driving element extending in the axial direction, wherein the first drive wheel and the second drive wheel are rotatably mounted on the second rail element at a distance from one another along the extension axis, so that in the first extension position the driving element is in engagement with the first drive wheel and out of engagement with the second drive wheel and that in the second extension position the driving element is out of engagement with the second drive wheel and in engagement with the second drive wheel.

[0032] In one embodiment of the invention, the first and second drive wheels are friction wheels and the driving element with the first and second driving sections is a friction surface extending in the axial direction.

[0033] In an alternative embodiment, the first drive wheel is a first gear and the second drive wheel is a second gear, wherein the driving element is a rack comprising the first driving section in the form of a first rack section and the second driving section in the form of a second rack section.

[0034] In one embodiment, the first and second drive wheels are effectively coupled to one another such that they experience a synchronous rotational movement during operation of the extension rail. Synchronous rotational movement is understood to mean a simultaneous rotational movement with the same angular velocity in the same direction of rotation and without a temporal shift in the start and end of the rotational movement of the first and second drive wheels. Such a synchronous rotational movement is realized in one embodiment by a mechanical coupling, e.g., by two gears coupled via a shaft or by a belt connecting the first drive wheel and the second drive wheel.

[0035] In one embodiment of the invention, the synchronous rotary movement is provided by an electric motor drive of the first and second drive wheels, using two electric motors whose rotary movements are electronically or electrically coupled.

[0036] In one embodiment, such an electrically driven pull-out rail comprises only the first and second rail elements and no additional rail elements. In one embodiment, the electrically driven pull-out rail also comprises a third rail element in addition to the first and second rail elements.

[0037] In one embodiment, the extension rail comprises a third rail element having a first end and a second end, wherein the second rail element and the third rail element are linearly displaceable relative to one another along the extension axis between a third extension position and a fourth extension position. In such an embodiment, the second rail element forms a center rail element. In the third extension position, the second end of the third rail element lies axially outside the second rail element, and in the fourth extension position, the first end of the third rail element lies axially outside the second rail element.As previously described for the interaction between the first and the second rail element, the third rail element or a third component connected to the third rail element and immovable relative to the third rail element along the extension axis has a first driving section and a second driving section, wherein the first driving section and the second driving section are spaced apart from one another along the extension axis, wherein the first driving section and the second driving section of the third rail element can be coupled to the drive unit of the second rail element, so that a positive connection or a frictional connection is formed, and can be uncoupled.The first driving section and the second driving section of the third rail element and the drive unit are arranged and designed such that in the fourth extension position the first driving section of the third rail element and the drive unit are uncoupled and the second driving section of the third rail element and the drive unit are coupled and that in the third extension position the first driving section of the third rail element and the drive unit are coupled and the second driving section of the third rail element and the drive unit are uncoupled.

[0038] In the zero position of the first, second and third rail elements relative to one another, the first and second driving sections of the first rail element and the drive unit of the second rail element as well as the first and second driving sections of the third rail element and the drive unit of the second rail element are coupled to one another at the same time.

[0039] Such a design enables the realization of a two-way pull-out rail as a full or over-extension.

[0040] In one embodiment of the invention, the third and second rail elements are mounted directly against one another such that the third and second rail elements are linearly displaceable relative to one another along the extension axis between the third extension position and the fourth extension position. In one embodiment, rolling elements, in particular bearing balls, are arranged between the running surfaces of the third rail element and the running surfaces of the second rail element. These reduce the friction between the third and second rail elements during linear movement.

[0041] In a further embodiment, an additional, non-synchronized (i.e., non-coupleable to the drive unit) intermediate rail element is provided between the first rail element and the second rail element, and optionally also between the third rail element and the second rail element. Such an extension makes it possible to support even higher loads during overextension.

[0042] In one embodiment of the invention, the third extension position is reached exactly when the first rail element and the second rail element have the first extension position relative to each other and the fourth extension position is reached exactly when the first and the second rail element have reached the second extension position relative to each other.

[0043] Such a design with three rail elements allows for full or over-extension. Such a design can be used not only to motor-drive the extension of three rail elements relative to each other in two extension directions, but also to create a manually operated two-way extension rail with synchronized movements of the first rail element relative to the second rail element and the second rail element relative to the third rail element.

[0044] It is understood that the designs of the first driving section and the second driving section of the third rail element are as diverse as those previously described for the first and second driving sections of the first rail element.

[0045] In one embodiment of the invention, the first driving section and the second driving section of the third rail element are each a friction surface section or a form-fitting section.

[0046] In one embodiment, the drive unit of the second rail element comprises a drive belt or a drive chain and two pulleys that guide the drive belt or the drive chain and are rotatably mounted on the second rail element.

[0047] In an alternative embodiment, in which the drive unit comprises a first and a second drive wheel, the first driving section and the second driving section of the third rail element are part of a driving element extending in the axial direction, wherein the first drive wheel and the second drive wheel of the drive unit of the second rail element are rotatably mounted on the second rail element at a distance from one another along the extension axis in such a way that in the third extension position the driving element of the third rail element is in engagement with the second drive wheel and out of engagement with the first drive wheel and in the fourth extension position the driving element of the third rail element is out of engagement with the second drive wheel and in engagement with the first drive wheel.

[0048] In one embodiment of the invention, the extension rail comprises, in addition to the first, second, and third rail elements, a fourth rail element with a first and a second end. The third and fourth rail elements are mounted on one another in such a way that the third and fourth rail elements are linearly displaceable relative to one another along an extension axis between a fifth extension position and a sixth extension position.wherein, in the fifth extension position, the second end of the fourth rail element lies axially outside the third rail element, and in the sixth extension position, the first end of the fourth rail element lies axially outside the third rail element. To enable synchronized extension movements of the fourth rail element in both extension directions relative to the third rail element, in such an embodiment, the third rail element also has a drive unit rotating relative to the third rail element. Furthermore, the second rail element has a first driving section and a second driving section.wherein the first driving section and the second driving section of the second rail element are spaced apart from one another along the extension axis, and wherein the first driving section and the second driving section of the second rail element can be coupled to the drive unit of the third rail element, so that a positive or frictional connection is formed, and can be uncoupled. The fourth rail element also has a first driving section and a second driving section, wherein the first driving section and the second driving section of the fourth rail element are spaced apart from one another along the extension axis, and wherein the first driving section and the second driving section of the fourth rail element can be coupled to the drive unit of the third rail element, so that a positive or frictional connection is formed.and are decoupleable. The first driving section and the second driving section of the second rail element, the first driving section and the second driving section of the fourth rail element, and the drive unit of the third rail element are arranged and configured such that, in the fifth extended position, the first driving section of the second rail element and the drive unit of the third rail element are decoupled, and the second driving section of the second rail element and the drive unit of the third rail element are coupled, and the first driving section of the fourth rail element and the drive unit of the third rail element are coupled, and the second driving section of the fourth rail element and the drive unit of the third rail element are decoupled.and that in the sixth extension position, the first driving section of the second rail element and the drive unit of the third rail element are coupled and the second driving section of the second rail element and the drive unit of the third rail element are uncoupled, and the first driving section of the fourth rail element and the drive unit of the third rail element are uncoupled and the second driving section of the fourth rail element and the drive unit of the third rail element are coupled.

[0049] In one embodiment of the invention, the axes of rotation of the drive units of the second rail element and of the third rail element are arranged next to one another in the vertical direction of the rail elements, i.e. in a vertical direction of the rail elements perpendicular to the first and second extension directions, so that the drive units and the driving sections do not interfere with one another. It is understood that the first and second driving sections of the second and fourth rail elements can have all alternative designs as previously described for the driving sections of the first rail element. Furthermore, the drive unit of the third rail element can have all alternative designs as previously described for the drive unit of the second rail element.

[0050] It is possible to provide additional rail elements on the fourth rail element, wherein these extensions are designed as previously described for the extension from three to four rail elements.

[0051] In particular, the description of the specific implementation options for the first and second drive sections of the third rail element and the drive unit of the second rail element demonstrates that, by implementing the rotatable drive unit on the second rail element, at least the relative movement between the first rail element and the second rail element and the relative movement between the second rail element and the third rail element can be synchronized with each other, or these two synchronized relative movements can even be driven by an electric motor. The pull-out rail according to the invention makes it possible to implement a motor-driven two-way pull-out rail.

[0052] Therefore, in one embodiment, the pull-out rail comprises an electric motor, which drives the rotating drive unit during operation of the pull-out rail. In one embodiment, this electric motor moves along with the second rail element. In one embodiment of the invention, the electric motor drives the first and / or second pulley and thus the drive belt or drive chain mounted on the pulleys. In an alternative embodiment of the invention, the electric motor drives at least the first drive wheel or the second drive wheel.

[0053] In one embodiment of the invention, the pull-out rail comprises an electric motor and a first drive wheel, wherein the electric motor is arranged such that the electric motor is stationary relative to the first rail element during operation of the pull-out rail. Likewise, the rotational axis of the drive wheel is stationary relative to the first rail element in this embodiment. The electric motor is operatively connected to the first drive wheel such that the electric motor rotationally drives the first drive wheel during operation of the pull-out rail. The second rail element additionally has a drive driver element extending in the axial direction. The first drive wheel and the drive driver element are coupleable to one another such that, in a coupled state, a rotational movement of the first drive wheel causes a linear movement of the second rail element.

[0054] It is understood that such an embodiment, in which the second rail element is driven by such an arrangement comprising an electric motor and a first drive wheel that is stationary relative to the first rail element, is particularly expedient if the pull-out rail also has a third rail element that is mounted so as to be linearly movable relative to the second rail element.

[0055] If the arrangement comprising an electric motor and a drive wheel only comprises the first drive wheel, this is preferably arranged centrally between the first and second ends of the first rail element. It is understood that with only a single, first drive wheel, only partial extension and not full or over-extension is possible. In one embodiment, the single drive wheel is always coupled to the drive driver element in all extension positions, so that the drive wheel always causes a relative movement between the first rail element and the second rail element upon corresponding rotation. In an alternative embodiment, also with only a single drive wheel, the drive wheel and the drive driver element can also be uncoupled. In this way, part of an extension movement can be motor-driven and another part of the extension movement can be manually driven.

[0056] In a further embodiment, the pull-out rail has, in addition to the first drive drive wheel, a second drive drive wheel, wherein the second drive drive wheel is arranged at a distance from the first drive drive wheel in the axial direction, wherein the first drive drive wheel and the drive driver element are decoupled, wherein the second drive drive wheel and the drive driver element are decoupled and uncoupled, so that in a coupled state of the second drive drive wheel and the drive driver element, a rotary movement of the second drive drive wheel causes a linear movement of the second rail element,wherein in the first extension position, the first drive wheel and the drive carrier element are coupled to one another and the second drive wheel and the drive carrier element are uncoupled, and wherein in the second extension position, the second drive wheel and the drive carrier element are coupled to one another and the first drive wheel and the drive carrier element are uncoupled.

[0057] It goes without saying that the rotational axis of the second drive wheel is also stationary relative to the first rail element. In such an embodiment, the distance between the two drive wheels allows for full or over-extension of the pull-out rail. In one embodiment, the first and second drive wheels are arranged to the left and right of the center of the first rail element, preferably at the ends of the first and second rail elements, in order to provide the greatest possible travel range for the two-way pull-out rail in both extension directions.

[0058] In one embodiment of the invention, at least the first drive wheel or the second drive wheel is a friction wheel and the driving element is an extended friction surface extending in the axial direction of the second rail element.

[0059] In an alternative embodiment, at least the first drive wheel is a first gear or the second drive wheel is a second gear, wherein the driving element is a rack.

[0060] In one embodiment of the invention, the first rail element and the second rail element each have at least one rail back and at least two legs extending from the rail back and carrying running surfaces for rolling elements. While in one variant each rail element has exactly two running surfaces for each bearing, variants are possible in which more than two running surfaces are provided on a rail element for each bearing. If a third rail element is also present in one embodiment, this therefore likewise has at least one rail back and at least two running surfaces for legs extending from the rail back and carrying rolling elements. In such an embodiment with a first, a second and a third rail element, the second rail element as the central rail thus has a total of at least four running surfaces for rolling elements.The running surfaces of the first rail element and at least two running surfaces of the second rail element face each other, and optionally at least two running surfaces of the second rail element face the running surfaces of the third rail element. In this way, the rolling elements can roll between at least two running surfaces of each of the two rail elements.

[0061] In one embodiment, the rotational axes of the drive unit, i.e., in particular, in one embodiment, the rotational axes of the pulleys or drive wheels, extend parallel to the rail backs of the rail elements. Further advantages, features, and possible applications of the present invention will become clear from the following description of embodiments and the accompanying figures. In the figures, identical elements are designated by identical reference numerals.

[0062] Figure 1 is a sectional view through a first embodiment of the pull-out rail according to the invention in a fully inserted state.

[0063] Figure 2 is a sectional view of the pull-out rail of Figure 1 in a partially extended state in a first pull-out direction.

[0064] Figure 3 is a sectional view of the pull-out rail of Figure 1 in a partially extended state in a second pull-out direction.

[0065] Figure 4 is an enlarged section of Figure 1.

[0066] Figure 5 is an enlarged section of Figure 2.

[0067] Figure 6 is an enlarged section of Figure 2.

[0068] Figure 7 is an isometric view of the pull-out rail from Figures 1 to 6 from an angle below in a partially extended state in the first extension direction.

[0069] Figure 8 is a sectional view of a second embodiment of the pull-out rail according to the invention in a fully inserted state.

[0070] Figure 9 is an enlarged section of the pull-out rail from Figure 8.

[0071] Figure 10 is a side view of a pull-out rail according to another embodiment in a partially extended state in the second extension direction.

[0072] Figure 11 is a partially broken away isometric view of the pull-out rail of

[0073] Figure 10 from diagonally above.

[0074] Figure 12 is an isometric view of a pull-out rail according to another embodiment with five rail elements, viewed obliquely from above. Figures 1 to 12 show a total of four different embodiments of two-way pull-out rails 4 according to the present invention. These two-way pull-out rails 4 can be extended in opposite first and second extension directions 7, 8, starting from the fully retracted states (zero position).

[0075] Each of the pull-out rails 4 has a first rail element 1, a second rail element 2 and a third rail element 3.

[0076] In the three embodiments of Figures 1 to 11, the first rail element 1 is the stationary rail element, the second rail element 2 is a center rail element, and the third rail element 3 is the inner rail element that supports the moving component. The embodiment of Figure 12 comprises a total of five rail elements, wherein the first rail element 1 is the stationary rail element and the fifth rail element 38 is the inner rail element that supports the moving component. In all embodiments, the third rail element 3 can be moved relative to the first rail element 1 to such an extent that it no longer overlaps with the first rail element 1 in a direction 6 perpendicular to the extension axis 5.

[0077] While all four embodiments form such full or over-extension drawers, with the respective drawer rail 4 comprising three rail elements 1, 2, 3, or five rail elements 1, 2, 3, 37, 38 (Figure 12), embodiments are also possible in which the respective drawer rail 4 forms only a partial extension with a motor drive in both extension directions. Such a variant may require only the first rail element 1 and the second rail element 2.

[0078] Along the extension axis 5, the second and third rail elements 2, 3 can be displaced relative to the first rail element 1 and, starting from a fully retracted state (zero position), in opposite first and second extension directions 7, 8. Such a fully retracted state is shown in Figures 1, 4, 8, and 9.

[0079] The idea underlying the invention is to combine a rotating drive unit 9 on the second rail element 2 with a first driving section 10 and a second driving section 11 on the first rail element 1 in such a way that a rotational movement of the drive unit 9, depending on the direction of rotation, causes an extension movement of the second rail element 2 relative to the first rail element 1 in the two mutually opposite first and second extension directions 7, 8.

[0080] In an embodiment with only the first and the second rail element 1, 2, which is not shown in the figures, it is sufficient to provide a motor drive only of the second rail element 2 relative to the first rail element 1.

[0081] However, all embodiments of Figures 1 to 12 show variants in which the drive unit 9 on the second rail element 2 simultaneously drives a parallel extension movement of the third rail element 3 relative to the second rail element 2. For this purpose, the third rail element 3 also has a first driving section 12 and a second driving section 13.

[0082] In the embodiments of Figures 1 to 7 and 10 and 11, the drive unit 9 is formed by a double toothed belt 14 as a drive belt, two toothed belt pulleys 15, 16 as deflection elements or pulleys, and an electric motor 17. The electric motor 17 drives the second toothed belt pulley 16.

[0083] The double toothed belt 14 has teeth 18 on its inner side 19, which mesh with the teeth of the toothed belt pulleys 15, 16, so that the double toothed belt 14 has no slippage relative to its toothed belt pulleys 15, 16.

[0084] The double toothed belt 14 also has teeth 21 on its outer side 20. These teeth 21 on the outer side 20 of the double toothed belt 14, in turn, engage with a first rack section 10 and a second rack section 11 as first and second driving sections of the first rail element 1 when the second rail element 2 is fully inserted relative to the first rail element 1 (see Figures 1 and 4). The first and second rack sections 10, 11 are arranged at first and second ends 22, 23 of the first rail element 1, which are opposite in the axial direction.The axial distance between the first and second rack sections 10, 11 is selected such that, depending on the extension direction 7, 8, at least one of the rack sections 10, 11 is always in engagement with the outer teeth 21 of the toothed belt 14, and rotation of the toothed belt 14 results in an extension movement of the rail elements 1, 2 relative to one another. The third rail element 3 also has a first rack section 12 and a second rack section 13 as the first and second driving sections of the third rail element 3. These rack sections 12, 13 of the third rail element 3 are both in engagement with the teeth 21 on the outer side 20 of the double toothed belt 14 when the second rail element 2 is fully inserted relative to the third rail element 3 (see Figures 1 and 4).The first and second rack sections 12, 13 of the third rail element 3 are also arranged at a distance from one another in the axial direction 5 at the first and second ends 24, 25 of the third rail element 3. The axial distance between the first and second rack sections 12, 13 of the third rail element 3 is selected such that, depending on the extension direction 7, 8, one of the rack sections 12, 13 is always in engagement with the outer teeth 21 of the toothed belt 14, and rotation of the toothed belt 14 also leads to an extension movement of the third rail element 3 relative to the second rail element 2.

[0085] In principle, it would also be possible to design the rack sections 10, 11 or 12, 13 of a rail element 1, 3 as a single, continuous rack. The only crucial factor for the functioning of the two-way extension rail 4 is that there are rack sections 5 spaced apart from each other in the axial direction.

[0086] The double toothed belt 14 not only drives the extension movements of the rail elements 1, 2, and 3 relative to each other, but also synchronizes them. It is immediately clear that the toothed belt 14 can also be used to synchronize the extension movements independently of the motorized extension rail 4.

[0087] If, as assumed for the illustration in Figure 2, the double toothed belt 14 rotates clockwise, the second rail element 2 and the third rail element 3 are displaced relative to the stationary first rail element 1 in the first extension direction 7. After both rack sections 10, 11 and 12, 13 of the first and third rail elements 1, 3 are originally engaged with the toothed belts 14, as shown in Figure 1, shortly after the start of the extension movement the first rack section 12 of the third rail element 3 disengages from the toothed belt 14. At the same time the second rack section 11 of the first rail element 1 disengages from the toothed belt 14. This operating situation is shown in Figure 2 and in enlarged detail in Figures 5 and 6. This disengagement is also referred to as uncoupling of the respective rack section 11, 12.In the fully extended state, the first end 24 of the third rail element 3 then projects in the axial direction 5 beyond the first end 33 of the second rail element 2, i.e. the first end 24 of the third rail element 3 lies in the axial direction outside the second rail element 2. Likewise, the second end 23 of the first rail element 1 then projects in the axial direction 5 beyond the second end 34 of the second rail element 2, i.e. the second end 23 of the first rail element 1 lies in the axial direction outside the second rail element 2.

[0088] If the direction of rotation of the toothed belt 14 is reversed, a retraction movement in the opposite second extension direction 8 takes place from the fully extended state in the first extension direction 7. This results in the first driving section 12 of the third rail element 3 re-engaging with the toothed belt, as does the second rack section 11 of the first rail element 1, immediately before reaching the zero position, i.e., the fully retracted state.

[0089] With continued counterclockwise rotation of the toothed belt 14, the extension movement begins in the second extension direction 8. Shortly after leaving the fully retracted state (Figures 1 and 4), the first rack section 10 of the first rail element 1 and the toothed belt 14, as well as the second rack section 13 of the third rail element 3 and the toothed belt 14, are uncoupled. The drive of the linear movements with the toothed belt 13 then takes place exclusively via the coupled second rack section 11 of the first rail element 1 and the first rack section 12 of the third rail element 3.

[0090] In the sense of the present application, Figure 3 shows a first extension position of the second rail element 2 relative to the first rail element 1 and a third extension position of the third rail element 3 relative to the second rail element 2. In contrast, Figure 2 shows a second extension position of the second rail element 2 relative to the first rail element 1 and a fourth extension position of the third rail element 3 relative to the second rail element 2.

[0091] In the embodiment of the invention according to Figures 1 to 7, the electric motor 17 is moved along with the second rail element 2, as it drives the toothed belt 14 via the second pulley 16. This is clearly visible in the isometric view of Figure 7.

[0092] In contrast, Figures 10 and 11 show an alternative drive concept for effecting relative movements between the second rail element 2 and the first rail element 1 as well as between the second rail element 2 and the third rail element 3. In the embodiment shown there, the electric motor 17 is not moved along with the second rail element 2. Instead, an electric motor 17 is provided on the stationary first rail element 1, which sets a first drive gear 26 in rotation via a gear 35 and a second drive gear 27 as drive drive wheels via an additional toothed belt (not shown in the figure).These drive gears 26, 27 each mesh through an opening in the back of the first rail 1 (shown in Figure 11) with a drive rack 28 fixed to the second rail element 2 as a drive driver element and, when rotated, cause a linear movement of the second rail element 2 relative to the first rail element 1. Such a drive concept with an electric motor 17 stationary relative to a first rail element 1 can also be used for a two-way extension rail 4 with more than three rail elements, as described below by way of example with reference to Figure 12. It is understood that the motor stationary relative to the first rail element then replaces the motor moving with one of the other rail elements.

[0093] The combination of first and second rack sections 10, 11 and 12, 13 on the first rail element 1 and the third rail element 3 as well as the toothed belt 14 is also the same in this embodiment as in the embodiment of Figures 1 to 7. Therefore, a linear movement of the second rail element 2 relative to the first rail element 1 also leads in the embodiment of Figures 10 and 11 to a synchronous, linear movement of the third rail element 3 relative to the second rail element 2.

[0094] Figure 12 shows a transfer of the concept of the pull-out rail 4 of Figures 1 to 7 to a five-link pull-out rail 4. This pull-out rail 4 has, in addition to the first, second, and third rail elements 1, 2, 3, a fourth rail element 37 and a fifth rail element 38. The synchronization of the pull-out movements of the first, second, and third rail elements 1, 2, 3 relative to one another in the first and second pull-out directions 7, 8 takes place, as in the embodiment of Figures 1 to 7, via a rotating drive unit 9 with a double toothed belt 14 deflected by means of two toothed belt pulleys on the second rail element 2, as well as a first and a second driving section 10, 11 in the form of rack sections on the first rail element 1, and a first and a second driving section 12, 13 in the form of rack sections on the third rail element 3.In addition, the third rail element 3 and the fourth rail element 37 also have guided double toothed belts 39, 40. The double toothed belt 39 of the third rail element 3 interacts with a first driving section and a second driving section 41 on the second rail element 2 as well as first and second driving sections (not visible in Figure 12) on the fourth rail element 37. The double toothed belt 40 of the fourth rail element 37, in turn, interacts with a first driving section and a second driving section 42 on the third rail element 3 as well as first and second driving sections (not visible in Figure 12) on the fifth rail element 38.

[0095] In the variant of Figure 12, the double toothed belt 39 of the third rail element 3 is driven by an electric motor 17 that moves with the third rail element 3, as previously described for the embodiment of Figures 1 to 7. Alternatively, the motor could also be arranged on the second rail element 2 or the fourth rail element 37, be carried along with them, and drive the respective toothed belts 14, 40 there.

[0096] Figures 8 and 9 illustrate an alternative concept for synchronizing the extension movements of the first rail element 1 relative to the second rail element 2, on the one hand, and of the third rail element 3 relative to the second rail element 2, on the other. This concept for synchronizing the relative movements of the rail elements 1, 2, 3 relative to one another can also be used, as implemented in the embodiments of Figures 8 and 9, for motor-driven drive of the extension movements in both extension directions 7, 8.

[0097] The first and second driving sections 10, 11 of the first rail element 1 and the first and second driving sections 12, 13 of the third rail element 3 are each part of a single rack 29, 30 as a driving element. The first and second rack sections 10, 11 of the first rail element 1 and the first and second rack sections of the third rail element are spaced apart from one another in the axial direction 5 as part of the respective rack 29, 30.

[0098] In this embodiment, as in the embodiment of Figures 1 to 7, the electric motor 17 moves along with the second rail element 2. The electric motor 17 synchronously drives a first and a second gear wheel 31, 32 as first and second drive wheels via a gear 35 and a belt drive (not shown).

[0099] The first and second gears 31, 32 are arranged at a distance from one another in the axial direction 5 at the first and second ends 33, 34 of the second rail element 2. During an extension movement starting from the fully inserted state shown in Figures 8 and 9, one of the two gears 31, 32 therefore always meshes with one of the two racks 29, 30 of the first and third rail elements 1, 3. A synchronous rotational movement of the two gears 31, 32 therefore enables a complete extension movement in both opposite extension directions 7, 8.

[0100] For the purposes of original disclosure, it is pointed out that all features as they become apparent to a person skilled in the art from the present description, the drawings, and the claims, even if they were specifically described only in conjunction with certain other features, can be combined both individually and in any combination with other features or groups of features disclosed herein, unless this has been expressly excluded or technical circumstances make such combinations impossible or pointless. A comprehensive, explicit presentation of all conceivable combinations of features is omitted here solely for the sake of brevity and readability of the description.

[0101] While the invention has been illustrated and described in detail in the drawings and the foregoing description, this illustration and description are given by way of example only and are not intended to limit the scope of the invention as defined by the claims. The invention is not limited to the disclosed embodiments.

[0102] Modifications of the disclosed embodiments will be apparent to those skilled in the art from the drawings, the description, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain features are claimed in different claims does not exclude their combination. Reference signs in the claims are not intended to limit the scope of protection.

[0103] List of reference symbols

[0104] 1 first rail element

[0105] 2 second rail element

[0106] 3 third rail element

[0107] 4 two-way pull-out rail

[0108] 5 Extension axis

[0109] 6 Direction perpendicular to the extension axis 5

[0110] 7 first pull-out direction

[0111] 8 second extension direction

[0112] 9 Drive unit

[0113] 10 first driving section of the first rail element

[0114] 11 second driving section of the first rail element

[0115] 12 first driving section of the third rail element

[0116] 13 second driving section of the third rail element

[0117] 14 double toothed belts

[0118] 15 first timing belt pulley

[0119] 16 second timing belt pulley

[0120] 17 Electric motor

[0121] 18 teeth on the inside 19

[0122] 19 Inside

[0123] 20 Outside

[0124] 21 teeth on the outside 20

[0125] 22 first end of the first rail element

[0126] 23 second end of the first rail element

[0127] 24 first end of the third rail element

[0128] 25 second end of the third rail element

[0129] 26 first drive gear

[0130] 27 second drive gear

[0131] 28 Drive rack

[0132] 29 Rack

[0133] 30 rack

[0134] 31 first gear

[0135] 32 second gear

[0136] 33 first end of the second rail element

[0137] 34 second end of the second rail element

[0138] 35 Gearbox 37 fourth rail element

[0139] 38 fifth rail element

[0140] 39, 40 double toothed belt

[0141] 41 second driving section of the second rail element 42 second driving section of the third rail element

Claims

P a t e n t a n s p r ü c h e 1. A pull-out rail (4) comprising a first rail element (1) with a first end (22) and a second end (23), and a second rail element (2), wherein the first rail element (1) and the second rail element (2) are linearly displaceable relative to one another along a pull-out axis (5) between a first pull-out position and a second pull-out position, and wherein, in the first pull-out position, the first end (22) of the first rail element (1) lies axially outside the second rail element (2), and, in the second pull-out position, the second end (23) of the first rail element (1) lies axially outside the second rail element (2), characterized in that the first rail element (1) or a first component connected to the first rail element (1) and immovable relative to the first rail element (1) along the pull-out axis has a first driving section (10) and a second driving section (11),wherein the first driving section (10) and the second driving section (11) are spaced apart from one another along the extension axis (5), and the second rail element (2) or a second component connected to the second rail element (2) and immovable relative to the second rail element (2) along the extension axis (5) has a drive unit (9) rotating relative to the second rail element (2), wherein the first driving section (10) and the second driving section (11) can be coupled to the drive unit (9) so that a positive connection or a frictional connection is formed, and can be uncoupled, and wherein the first driving section (10), the second driving section (11) and the drive unit (9) are arranged and designed such that in the first extension position, the first driving section (10) and the drive unit (9) are uncoupled and the second driving section (11) and the drive unit (9) are coupled, and, that in the second extension position the first driving section (10) and the drive unit (9) are coupled and the second driving section (11) and the drive unit (9) are uncoupled.

2. Pull-out rail (4) according to the preceding claim, wherein the drive unit (9) comprises a drive belt (14) or a drive chain, wherein two deflection elements (15, 16) guiding the drive belt (14) or the drive chain are provided on the second rail element (2) or the second component, and wherein the first and the second driving section (10, 11) are each at least one friction surface section or one form-fitting section (10, 11).

3. Pull-out rail (4) according to the preceding claim, wherein the drive belt is a double toothed belt (14) with teeth (21) on an outer side (20) and with teeth (18) on an inner side (19), wherein the first driving section is a first positive-locking section (10) and the second driving section is a second positive-locking section (11), wherein the first and the second positive-locking section (10, 11) can be brought into engagement with the teeth (21) on the outer side (20) of the double toothed belt (14), wherein at least one of the two deflection elements comprises a toothed belt pulley (15, 16) rotatably provided on the second rail element or the second component, and wherein the toothed belt pulley (15, 16) meshes with the teeth (18) on the inner side (19) of the double toothed belt (14).

4. Pull-out rail (4) according to claim 1, wherein the drive unit (9) comprises a first drive wheel (31) and a second drive wheel (32), wherein the first driving section (10) and the second driving section (11) are part of a driving element (29) extending in the axial direction, wherein the first drive wheel (31) and the second drive wheel (32) are rotatably mounted on the second rail element (2) at a distance from one another along the pull-out axis (5) in such a way that in the first pull-out position the driving element (29) is in engagement with the first drive wheel (31) and out of engagement with the second drive wheel (32) and that in the second pull-out position the driving element (29) is out of engagement with the first drive wheel (31) and in engagement with the second drive wheel (32).

5. Pull-out rail (4) according to the preceding claim, wherein the first drive wheel is a first gear (31) and the second drive wheel is a second gear (32) and wherein the driving element is a rack (29).

6. Pull-out rail (4) according to claim 4 or 5, wherein the first drive wheel (31) and the second drive wheel (32) are effectively coupled to one another in such a way that they undergo a synchronous rotary movement during operation of the pull-out rail (4).

7. Pull-out rail (4) according to one of the preceding claims, wherein the pull-out rail (4) comprises a third rail element (3) with a first end (24) and a second end (25), wherein the second rail element (2) and the third rail element (3) are linearly displaceable relative to one another along the pull-out axis (5) between a third pull-out position and a fourth pull-out position, wherein in the third pull-out position the second end (25) of the third rail element (3) lies outside the second rail element (2) in the axial direction of the pull-out axis (5) and in the fourth pull-out position the first end (24) of the third rail element (3) lies outside the second rail element (2) in the axial direction,wherein the third rail element (3) or a third component connected to the third rail element (3) and immovable relative to the third rail element (3) along the extension axis (5) has a first driving section (12) and a second driving section (13), wherein the first driving section (12) and the second driving section (13) are spaced apart from one another along the extension axis (5), wherein the first driving section (12) and the second driving section (13) of the third rail element (3) can be coupled to the drive unit (9) so that a positive connection or a frictional connection is formed, and can be uncoupled, wherein the first driving section (12) and the second driving section (13) of the third rail element (3) and the drive unit (9) are arranged and designed in such a way,that in the fourth extension position, the first driving section (12) of the third rail element (13) and the drive unit (9) are uncoupled and the second driving section (13) of the third rail element (3) and the drive unit (9) are coupled, and that in the third extension position, the first driving section (12) of the third rail element (3) and the drive unit (9) are coupled and the second driving section (13) of the third rail element (3) and the drive unit (9) are uncoupled.

8. Pull-out rail (4) according to the preceding claim as far as dependent on claim 2, wherein the first driving section (12) and the second driving section (13) of the third rail element (3) are each a friction surface section or a form-fitting section (12, 13).

9. Pull-out rail (4) according to claim 7 or 8 as far as dependent on claim 4, wherein the first driving section (12) and the second driving section (13) of the third rail element (4) are part of a driving element (30) extending in the axial direction, wherein the first drive wheel (31) and the second drive wheel (32) are rotatably mounted on the second rail element (2) at a distance from one another along the pull-out axis (5) in such a way that in the third pull-out position the driving element (30) of the third rail element (3) is in engagement with the second drive wheel (32) and out of engagement with the first drive wheel (31) and that in the fourth pull-out position the driving element (30) of the third rail element (3) is out of engagement with the second drive wheel (32) and in engagement with the first drive wheel (31).

10. Pull-out rail (4) according to one of the preceding claims, wherein the pull-out rail (4) has an electric motor (17), wherein the electric motor (17) is arranged on the second rail element (2) in such a way that the electric motor (17) is moved along with the second rail element (2) during operation of the pull-out rail (4), and wherein the electric motor (17) is effectively connected to the drive unit (9) in such a way that the electric motor (17) drives the drive unit (9) during operation of the pull-out rail (4).

11. Pull-out rail (4) according to one of claims 1 to 9, wherein the pull-out rail (4) comprises an electric motor (17) and a first drive wheel (26), wherein the electric motor (17) is arranged such that the electric motor (17) is stationary relative to the first rail element (1) during operation of the pull-out rail (4), wherein the electric motor (17) is operatively connected to the first drive wheel (26) such that the electric motor (17) drives the first drive wheel (26) in rotation during operation of the pull-out rail (4), wherein the second rail element (2) comprises a drive driver element (28) extending in the axial direction, wherein the first drive wheel (26) and the drive driver element (28) can be coupled to one another, so that in a coupled state of the first drive wheel (26) and the drive driver element (28), a rotational movement of the first drive wheel (26) causes a linear movement of the second rail element (2).

12. Pull-out rail (4) according to the preceding claim, wherein the pull-out rail (4) has a second drive wheel (27), wherein the second drive wheel (27) is arranged at a distance from the first drive wheel (26) in the axial direction, wherein the first drive wheel (26) and the drive driver element (28) are decoupled, wherein the second drive wheel (27) and the drive driver element (28) are decoupled and uncoupled, so that in a coupled state of the second drive wheel (27) and the drive driver element (28), a rotary movement of the second drive wheel (27) causes a linear movement of the second rail element (2),wherein in the first extension position, the first drive wheel (26) and the drive element (28) are coupled to one another and the second drive wheel (27) and the drive element (28) are uncoupled, and wherein in the second extension position, the second drive wheel (27) and the drive element (28) are coupled to one another and the first drive wheel (26) and the drive element (28) are uncoupled.

13. Pull-out rail (4) according to one of the preceding claims as far as dependent on claim 7, wherein the pull-out rail (4) comprises a fourth rail element (37) with a first and a second end, wherein the third rail element (3) and the fourth rail element (27) are linearly displaceable relative to one another along the pull-out axis (5) between a fifth pull-out position and a sixth pull-out position, wherein in the fifth pull-out position the second end of the fourth rail element (37) lies in the axial direction outside the third rail element (), wherein, in the sixth extension position, the first end of the fourth rail element (36) lies axially outside the third rail element (3), wherein the third rail element (3) has a drive unit (9) rotating relative to the third rail element (3), wherein the second rail element (2) has a first driving section and a second driving section (41), wherein the first driving section and the second driving section (41) of the second rail element (2) are spaced apart from one another along the extension axis (5), wherein the first driving section and the second driving section (41) of the second rail element (2) can be coupled to the drive unit (9) of the third rail element (3) so that a positive connection or a frictional connection is formed, and can be uncoupled, wherein the fourth rail element (37) has a first driving section and a second driving section (42),wherein the first driving section and the second driving section (42) of the fourth rail element (37) are spaced apart from one another along the extension axis (5), wherein the first driving section and the second driving section (42) of the fourth rail element (37) can be coupled to the drive unit (9) of the third rail element (3) so that a positive connection or a frictional connection is formed, and can be uncoupled, wherein the first driving section and the second driving section (41) of the second rail element (2), the first driving section and the second driving section (42) of the fourth rail element (37) and the drive unit (9) of the third rail element (3) are arranged and designed in such a way,that in the fifth extension position, the first driving section of the second rail element (2) and the drive unit (9) of the third rail element (3) are uncoupled and the second driving section (41) of the second rail element (2) and the drive unit (9) of the third rail element (3) are coupled, and the first driving section of the fourth rail element (37) and the drive unit (9) of the third rail element (3) are coupled and the second driving section (42) of the fourth rail element (37) and the drive unit (9) of the third rail element (3) are uncoupled, and, that in the sixth extension position, the first driving section of the second rail element (2) and the drive unit (9) of the third rail element (3) are coupled and the second driving section (41) of the second rail element (2) and the drive unit (9) of the third rail element (3) are uncoupled and the first driving section of the fourth rail element (37) and the drive unit (9) of the third rail element (3) are uncoupled and the second driving section (41) of the fourth rail element (37) and the drive unit (9) of the third rail element (3) are coupled.

Images