The present invention relates to a drawer pull-out guide for movably mounting a drawer on a furniture carcass, comprising:
The rails of a drawer pull-out guide are often produced from a flat metal sheet, which is processed to form a profile rail by subsequent bending and/or reshaping. The loads on the drawer pull-out guide in the horizontal and in the vertical direction are absorbed by the finished profiles, as a result of which the drawer connected to the drawer pull-out guide can be guided stably.
The requirement for metal, which is normally necessary for the production of a drawer pull-out guide, represents a general problem. High material usage leads to a high weight and to increased costs in series manufacturing. It is therefore desirable to use as little metal as possible, especially as a resource-conserving use of raw materials brings with it both ecological and economic advantages.
The object of the present invention is to specify a drawer pull-out guide of the type mentioned at the beginning in which the named problems of the state of the art are at least partially avoided.
According to the invention, the ratio of the dead weight of the drawer pull-out guide to the maximum load-bearing capacity of the drawer pull-out guide is less than 1 to 50, preferably less than 1 to 57, particularly preferably less than 1 to 65.
Until now, a person skilled in the art in the field of the furniture fittings industry has assumed that a particular material usage is required to implement a drawer pull-out guide which has a particular stability with a predefined maximum load-bearing capacity.
Conventional drawer pull-out guides from the applicant have, for example, a ratio of the dead weight of the drawer pull-out guide to the maximum load-bearing capacity of the drawer pull-out guide of 1 to 40 or above. Lower ratios did not appear to be implementable.
Within the framework of the invention, the applicant's experts have surprisingly found, contrary to this expectation, that it is possible to advance into an entirely different regime during the construction of drawer pull-out guides.
In this way, the material usage can be significantly reduced, e.g. halved, which is accompanied by a substantial reduction of the manufacturing costs and at the same time by a substantial resource efficiency, in particular in view of the large quantities prevalent in the furniture fittings industry.
It may be pointed out that the technical testing and assessment of drawer pull-out guides is standardized at least in the European region. In this connection, reference may be made to the standard DIN EN 15338, in which the strength and durability of extension elements and their components are defined. However, this standard makes no statements regarding the ratio of the dead weight to the maximum load-bearing capacity of a drawer pull-out guide.
The maximum load-bearing capacity is not an arbitrary variable, but is fixed for a person skilled in the art. The maximum load-bearing capacity is normally also recorded on the drawer pull-out guide, e.g. by stamps.
Advantageously, the at least one drawer rail is displaceable relative to the carcass rail over a pull-out length between a pushed-in end position and a pulled-out end position. The at least one drawer rail has a front end to be connected to a front panel of the drawer, and in the pulled-out end position the front end of the at least one drawer rail can drop by a maximum of 4% of the pull-out length in the case of a load which corresponds to the maximum load-bearing capacity.
The invention is suitable in a particularly advantageous manner for a drawer pull-out guide which has a length of between 200 mm and 650 mm in a completely pushed-in state, and/or has a dead weight of between 125 g and 550 g, and/or has a maximum load-bearing capacity of between 15 kg and 35 kg, and/or is manufactured at least predominantly from steel. According to a specific embodiment it can be provided that the drawer pull-out guide has a maximum load-bearing capacity of 25 kg, a length of 500 mm and a dead weight of approx. 350 g.
Alternatively or additionally, at least one rolling body is arranged between the carcass rail and the at least one drawer rail. Preferably, the at least one rolling body is mounted rotatable about an axis of rotation, and particularly preferably the axis of rotation is aligned transverse to the longitudinal direction, and/or at least one carriage, in particular made of plastic, is provided, in which the at least one rolling body is arranged, and/or the at least one rolling body is formed substantially cylindrical, and/or the at least one rolling body consists at least predominantly of plastic. Such a drawer pull-out rail differs, in terms of its design, significantly from other drawer pull-out rails, such as e.g. heavy-duty pull-outs or ball guides.
It has proved to be favorable that the drawer pull-out guide is formed at least in portions from a flat metal sheet, which has a material thickness of between 0.5 mm and 1.0 mm, preferably a material thickness of 0.7 mm. A much thinner metal sheet is thus used than in the case of a conventional drawer pull-out guide with a comparative design.
In a particularly advantageous manner, the ratio, which is low compared with the state of the art, of the dead weight of the drawer pull-out guide to the maximum load-bearing capacity of the drawer pull-out guide can be implemented in that the drawer pull-out guide has at least one property, preferably more than one, selected from the following group of properties i. to v.:
Property i.: At least one of the rails has, in a cross section normal to the longitudinal direction, at least one profile formed from at least one flat metal sheet with two longitudinal edges running parallel to each other. The profile has at least one foldover with at least a double material thickness on at least one longitudinal edge, preferably on both longitudinal edges.
Property ii.: The carcass rail has at least one fastening portion with a fastening side which, during installation of the drawer pull-out guide on the furniture carcass, can be attached to the furniture carcass at least in portions. The at least one fastening portion has at least one, preferably circular, opening for a fastening means, preferably a screw, to pass through. The at least one opening, on a second side spaced apart from the fastening side by a material thickness of the fastening portion, is surrounded by a ridge which protrudes transversely from the second side of the fastening portion.
Property iii.: At least one of the rails has, in a cross section normal to the longitudinal direction, a profile formed from at least one flat metal sheet. At least one end surface of the profile, in particular two, is formed with a taper.
Property iv.: At least one of the rails has, in a cross section normal to the longitudinal direction, at least one profile formed from at least one flat metal sheet with two longitudinal edges running parallel to each other. At least one embossing extending at least in areas over at least two lateral surfaces of the profile arranged substantially orthogonal to each other is arranged for reinforcing the profile, and the lateral surfaces are arranged in the longitudinal direction and the at least one embossing is arranged substantially orthogonal to the longitudinal direction.
Property v.: At least one of the rails has, in a cross section normal to the longitudinal direction, at least one profile formed from at least one flat metal sheet with two longitudinal edges running parallel to each other. At least two embossings are provided, which are preferably arranged on at least two lateral surfaces oriented substantially orthogonal to and/or adjoining each other and/or extend over at least two lateral surfaces at least in areas. The at least two embossings face in the direction of an inner area and in the direction of an outer area of the at least one rail in an alternating manner, in particular wherein the at least two embossings adjoin each other in the longitudinal direction.
Property i. is associated with the following technical advantages:— Firstly a simple process of bending the metal sheet is possible, secondly the stiffness of the profile can be increased in the area of the foldover,
In connection with property i., it has proved to be advantageous that the at least one foldover is arranged on at least one longitudinal edge of the carcass rail. The foldover can be attached during fastening of the carcass rail to the furniture carcass, and/or has at least two metal sheet portions resting against each other at least in areas on the at least one longitudinal edge. Preferably, the at least two metal sheet portions have at least one common punching, and/or has at least one crack running in the longitudinal direction on the at least one longitudinal edge in a cross section normal to the longitudinal direction, and preferably the at least one foldover is formed on at least one longitudinal edge of the carcass rail.
Alternatively or additionally, the drawer pull-out guide has at least one rolling body, which is mobile at least in portions in the longitudinal direction along the at least one foldover.
Furthermore, in connection with property i., it can be advantageous that the at least one drawer rail has at least one foldover with at least a double material thickness on both longitudinal edges. The two foldovers are aligned transverse, preferably substantially at right angles, to each other and/or one of the two foldovers is turned inwards and the other of the two foldovers is turned outwards.
Property ii. is associated with the following technical advantages:
In connection with property ii., it has proved to be advantageous that the ridge is formed substantially toroidal in a cross section, and/or is formed in one piece together with the at least one fastening portion, and/or is produced in the at least one fastening portion by embossing.
Property iii. is associated with the following technical advantages:—
In connection with property iii., it has proved to be advantageous that the taper includes an angle in the range between 60° and 140°, preferably between 75° and 105°, particularly preferably of substantially 90°. Preferably, at least one end surface, preferably both, is formed substantially burr-free, and/or has a taper cross section, parallel to the longitudinal extent of the metal sheet, substantially in the shape of a, preferably isosceles, triangle, and preferably the taper cross section is formed convex and/or concave.
For example, identical or different depths and/or geometries can be used for at least one indentation in the metal sheet, which manifests as a taper in the drawer pull-out guide. A geometry of the taper can be adjusted flexibly via a geometry of the indentation. The taper can act as a defined predetermined breaking point for tearing and/or breaking off.
Properties iv. and v. are associated with the following technical advantages:
The embossing can also be called a lock beading or reinforcing bead in the sense of a plastic deformation as work hardening, which is forced into a metal sheet or a profile, in order to generate an increase in stability or strength—in particular by increasing section moduli and/or moments of inertia and/or reducing vibrations as well as deformations generated by pressure, tension, torsion, bending et cetera.
In connection with properties iv. and v., it has proved to be advantageous that at least one carriage with at least one rolling body and/or sliding body is arranged or arrangeable on the drawer pull-out guide. The at least one embossing is arranged on the at least one carcass rail and/or the at least one drawer rail in such a way that the at least one embossing is traversable contactlessly in the longitudinal direction by the at least one carriage and/or the at least one rolling body and/or sliding body.
A user-friendly guiding of the drawer pull-out guide can thereby be guaranteed, wherein the movement of the at least one carriage is not impaired by the at least one embossing.
Alternatively or additionally, precisely three embossings for reinforcing the profile are arranged at least in areas on at least two substantially orthogonally arranged lateral surfaces of the at least one rail.
In the state of the art, small material thicknesses are associated with significant performance losses and/or lifetime losses during operation of the rail. Through three alternating relative to adjoining lateral surfaces and/or relative to an inner area and an outer area of the at least one rail—in particular drawer rail, carcass rail and/or center rail—small material thicknesses can also be used in the case of rails with high load requirements or heavy movable furniture parts.
It has proved to be particularly favorable that the at least two embossings are arranged on the same lateral surface or on the same lateral surfaces extending over at least two lateral surfaces and/or on the at least two lateral surfaces in an alternating manner. Preferably, the at least two embossings are arranged in a transition area of the at least two lateral surfaces in an alternating manner relative to the inner area and the outer area.
For example, embossings which are aligned in the inner area and outer area in an alternating manner can be arranged on one lateral surface. Alternatively or additionally, one of the embossings can extend across two lateral surfaces and/or an alternating arrangement of the embossings relative to the lateral surfaces can be provided, and two embossings arranged next to each other are oriented substantially orthogonal to each other.
According to an embodiment, at least, preferably in the case of possibly present groups precisely, two embossings face in the direction of the inner area of the at least one rail and one embossing is arranged in the middle between the at least two embossings and faces in the direction of the outer area of the at least one rail to increase a tensile/compressive strength.
A tensile/compressive strength of the rail is gradually increased by an increasing number of embossings. A rail withstands particularly large forces without plastic and/or improper elastic deformation due to alternating embossings and in particular due to an embossing oriented in the opposite direction (inner or outer area) in the middle between two embossings. In addition, the at least one embossing can serve as a support during installation of the drawer pull-out guide.
And finally, in connection with properties iv. and v., it is appropriate that the at least one embossing extends in the orthogonal direction relative to the longitudinal direction of the at least one rail over an area of between one third and three quarters of the lateral surface and/or extends over an area of less than one third, preferably one quarter, of a lateral surface adjoining this lateral surface.
The at least one embossing can generally extend in the direction orthogonal to the longitudinal direction across an entire lateral surface. Such a structural design is generally not necessary due to lower loads on free longitudinal edges. In particular, in the case of an alternating arrangement of embossings with respect to the lateral surfaces, an extent of the individual embossings with respect to a lateral surface can be reduced as both lateral surfaces are strengthened by embossings. This can enhance an esthetic appearance and/or reduce manufacturing effort. The at least one embossing can end in a transition area of the lateral surfaces or extend across it.
Further details and advantages of the present invention arise from the following description of the figures, in which:
The drawer pull-out guides 4 comprise a carcass rail 9, which is to be fastened to the furniture carcass 2 via a fastening portion 11. Furthermore, at least one drawer rail 10 is provided, which is to be connected to the drawer 3 and which is mounted mobile relative to the stationary carcass rail 9.
The drawer pull-out guide 4 can possibly also have a center rail, which is mobile between the carcass rail 9 and the drawer rail 10 and through which it is possible to pull the drawer 3 out completely in relation to the furniture carcass 2.
The drawer side walls 7 can in each case have a hollow-chamber profile 7a, which is connected or connectable to the at least one drawer rail 10 of the drawer pull-out guide 4.
The at least one drawer rail 10 has a front end connected to the front panel 5 of the drawer 3 and in the pulled-out end position the front end of the at least one drawer rail 10 can drop by a maximum of 4% of the pull-out length (n) in the case of a load which corresponds to the maximum load-bearing capacity. The drop of the front end is indicated with an arrow.
The fastening portion 11 has a fastening side 19, which can be attached to the furniture carcass 2 at least in portions during installation of the drawer pull-out guide 4 on the furniture carcass 2.
The fastening portion 11 can have at least one, preferably circular, opening 12 for a fastening means 28, in particular a screw 28a, to pass through, through which opening the fastening portion 11 is to be fastened to the furniture carcass 2a.
On a second side 20 facing away from the fastening side 19, the at least one opening 12 is surrounded by a, preferably annular, ridge 21, which protrudes transversely from the second side 20 of the fastening portion 11.
The screwhead of the screw 28a is at least partially countersinkable through this ridge 21. In addition, the peripheral rim of the opening 12 is strengthened by the ridge 21, wherein the risk of damage to the peripheral rim of the opening 12 is reduced.
The fastening portion 11 and/or the carcass rail 9 and/or the drawer rail 10 can in each case have at least one embossing 13 (also called lock beading or reinforcing bead). At least one opening 12 for a screw 28a to pass through can be arranged between two embossings 13, as a result of which the section modulus can be increased in this area.
The fastening portion 11 of the carcass rail 9 has a fastening side 19, which can be attached to the furniture carcass 2 at least in portions during fastening of the carcass rail 9 to the furniture carcass 2.
The carcass rail 9 and/or the drawer rail 10 is or are bent out of a flat metal sheet with two longitudinal edges 14a, 14b (drawer rail 10) and 15a, 15b (carcass rail 9) to form a profile 9a, 10a. The flat metal sheet has a material thickness (X).
The flat metal sheet from which the profile 9a, 10a is formed can for example have a material thickness (X) of between 0.5 mm and 1.0 mm, preferably a material thickness (X) of 0.7 mm.
The profile 9a of the carcass rail 9 and/or the profile 10a of the drawer rail 10 has or have at least one foldover 16, 17 with at least a double material thickness (2X) on at least one longitudinal edge 14a, 14b, 15a, 15b, preferably on both longitudinal edges 14a, 14b, 15a, 15b. The at least one foldover 16, 17 preferably has precisely double the material thickness (2X).
If expedient, however, the foldover 16, 17 can also be folded three or more times, as a result of which there is a triple or multiple material thickness (X).
At least one foldover 16, 17 can be arranged on a longitudinal edge 15b of the carcass rail 9, wherein this foldover 16, 17 can be attached during fastening of the carcass rail 9 to the furniture carcass 2.
According to an embodiment it can be provided that on the at least one longitudinal edge 14a, 14b, 15a, 15b the at least one foldover 16, 17 has at least two metal sheet portions 24a, 24b resting against each other at least in areas.
The at least one drawer rail 10 can have at least one foldover 16, 17 with at least a double material thickness (2X) on both longitudinal edges 14a, 14b, wherein the two foldovers 16, 17 are aligned transverse, preferably substantially at right angles, to each other and/or wherein one of the two foldovers 16, 17 is turned inwards and the other of the two foldovers 16, 17 is turned outwards.
At least one foldover 16, 17 can have at least one crack 18 running in the longitudinal direction (L) on the at least one longitudinal edge 14a, 14b, 15a, 15b in a cross section normal to the longitudinal direction (L), preferably wherein the at least one foldover 16, 17 is formed on at least one longitudinal edge 15a of the carcass rail 9.
The at least one fastening portion 11 can have at least one, preferably circular, opening 12 for a fastening means 28 (
According to an embodiment it can be provided that, on a second side spaced apart from the fastening side 19 by a material thickness (X) of the fastening portion 11, the at least one opening 12 is surrounded by a ridge 21 which protrudes transversely from the second side 20.
The stiffness of the fastening portion 11 in the area of the opening 12 can be substantially improved by the ridge 21 which surrounds the opening 12, which is advantageous in particular in the case of use with metal sheets with thin material thickness (X).
At least one embossing 13 can have a longitudinal direction, which extends transverse to the longitudinal direction (L) of the carcass rail 9. At least one embossing 13 or several embossings 13 can be arranged on the vertical leg of the fastening portion 11 and/or on the transverse leg of the fastening portion 11.
It is preferably provided that the rolling bodies 23a, 23b, 23c are mounted in a common carriage 22, wherein the carriage 22 is mounted mobile between the carcass rail 9 and the at least one drawer rail 10.
According to possible embodiments it can be provided that at least one rolling body 23a, in an installation position, has a cylindrical shape, is rotatable about a horizontal axis and is mobile along the foldover 16 of the drawer rail 10.
At least one further rolling body 23a, in an installation position, is rotatable about a horizontal axis and is mobile along the foldover 17 of the carcass rail 9.
At least one further rolling body 23c, in an installation position, is rotatable about a vertical axis and is mobile along a portion of the carcass rail 9 with a double wall thickness (2X).
The carriage 22 with the rolling bodies 23a, 23b, 23c (which can alternatively or additionally also be formed as sliding bodies) is arranged on the drawer pull-out guide 4, wherein the embossings 13 are arranged on the carcass rail 9 and the drawer rail 10 in such a way that the embossings 13 are traversable contactlessly in the longitudinal direction L by the carriage 22 and the rolling bodies 23a, 23b, 23c.
On a second side 20 spaced apart from the fastening side 19 by a material thickness (X), the at least one opening 12 is surrounded by a ridge 21, which protrudes transversely from the second side 20 of the fastening portion 11. The screwhead of a screw 28a for fastening the fastening portion 11 to the furniture carcass 2, in an installed state, is received inside the annular ridge 21 at least in areas, preferably substantially completely.
The metal sheet portions 24a, 24b of the foldover 16, 17 resting against each other are connected to each other by at least one common punching 25, 26. In this way the foldover 16, 17 can be additionally stabilized.
According to an embodiment two punchings 25, 26 spaced apart from each other in the longitudinal direction (L) are provided.
According to preferred embodiments it can be provided that
The at least one punching 25, 26 can thus assume a dual function. On the one hand, the punching 25, 26 serves to stabilize the metal sheet portions 24a, 24b of the foldover 16, 17 resting against each other.
On the other hand, the laterally protruding punching 25, 26 is provided to limit a route of the carriage 22 in the longitudinal direction (L). The carriage 11 obtains a defined end position through the punching 25, 26 and therefore cannot overrun an end of the carcass rail 9 and/or of the at least one drawer rail 10.
The embossings 13 lying outside in the group extend in each case between one third and three quarters of the lateral surface 31 and end in the transition area of the adjoining lateral surface 31, wherein the embossing 13 arranged in the middle extends across the entire lateral surface 31 and ends in the transition area. An extension of embossings 13 across the transition area is likewise conceivable.
The embossings 13 have a cross section tapering in the direction toward the longitudinal edges 15a, 15b, wherein three embossing surfaces are oriented relative to each other in the manner of a truncated pyramid, as larger stresses generally occur in the area of a transition of the lateral surfaces 31 than in the area of the longitudinal edges 15a, 15b.
For each group two embossings 13 are arranged on the same lateral surface 31 and end in a transition area of the adjoining lateral surface 31. The embossings are arranged on the two adjoining lateral surfaces 31 in an alternating manner, wherein the three embossings 13 of the respective group are arranged in a transition area of the two lateral surfaces 31 in an alternating manner relative to the inner area 32 and the outer area 33. The three embossings 13 of the groups face into the inner area 32 and into the outer area 33 in an alternating manner, wherein two embossings 13 face in the direction of the inner area 32 of the carcass rail 10 and one embossing 13 is arranged in the middle between the two embossings 13 and faces in the direction of the outer area 33 of the carcass rail 9 to increase a tensile/compressive strength.
It is recognizable in
To form the taper 30 two indentations 36 have been introduced into the flat metal sheet, which extend over a width of the metal sheet oriented orthogonal to the longitudinal direction L and are arranged on both top surfaces of the metal sheet. The cross section of the indentation 36 is generally as desired and can represent for example a triangle shape or an elliptical portion as in the schematic detail sections of a cross section of a metal sheet. The geometry and depths of a plurality of indentations 36 can generally also vary, wherein four indentations 36 are particularly preferably utilized in order to form a drawer rail 10, a carcass rail 9 or a center rail with in each case one taper 30 per end surface 30 using non-cutting mechanical separation.
A metal sheet with two indentations 36 with a trapezoidal cross section, which results in two tapers 30—in each case one taper per drawer rail 10—after a cutting-to-length process of the drawer rail 10, can be seen in
A taper cross section 35 parallel to the longitudinal extent of the metal sheet has the shape of an isosceles triangle, wherein other geometries are possible in the taper cross section 35 depending on the indentations 36—for example a right-angled triangle in the case of an indentation 36 on one side. The taper 30 can have a taper ridge due to manufacturing and can be designed concave or convex.
Number | Date | Country | Kind |
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A 50614/2021 | Jul 2021 | AT | national |
The present application is a continuation of International Application PCT/AT2022/060254, filed Jul. 15, 2022. Thus, all of the subject matter of International Application PCT/AT2022/060254 is incorporated herein by reference.
Number | Date | Country | |
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Parent | PCT/AT22/60254 | Jul 2022 | US |
Child | 18418959 | US |