BACKGROUND OF THE INVENTION
The present invention relates to a drawer pull-out guide comprising at least one guide rail. The guide rail includes a longitudinally extending first limb and at least one longitudinally extending second limb angled from the first limb, and the first limb and the second limb are connected to one another along their longitudinal direction by an angled region.
Moreover, the invention concerns a drawer pull-out guide comprising at least one guide rail of the type to be described, and a method for producing a guide rail for a drawer pull-out guide.
Such guide rails are used for drawer pull-out guides, so that a drawer can be supported so as to be extendable relative to a furniture carcass in a mounted position. The drawer pull-out guides usually include a first guide rail configured to be fixed to a furniture carcass, and at least one second guide rail configured to be displaceable relative to the first guide rail. In order to enable the drawer to be fully extended relative to the furniture carcass, a displaceably supported third guide rail may be arranged. For supporting the displaceable guide rails, rolling bodies are provided, the rolling bodies being supported in a running carriage or also in a plurality of displaceable running carriages. By specially formed guide rails, the stability and the loading capacity of the drawer pull-out guide can be improved. When using large material thicknesses for the guide rails, the guide rails form a round angled region, whereby an increased installation space has to be provided.
SUMMARY OF THE INVENTION
It is an object of the invention to propose a more compact guide rail of a drawer pull-out guide, thereby avoiding the above-discussed drawbacks.
According to the invention, the angled region includes at least one material diminution extending along the angled region and formed by a recess.
In other words, in an angled region enclosed by the two limbs of the guide rail (that is to say, on an inner side or on an inner radius of the angled region between the two limbs), at least one material diminution, formed by a recess, having a reduced material thickness is provided. The two limbs are angled to one another about a notional axis extending in a longitudinal direction of the recess. By the material diminution formed by the recess, a compression caused by compressive stress on the inside of the angled region can be prevented when the guide rail is produced by a bending or roll forming operation. As a result, the limbs can be angled to one another to a larger extent, for example in such a way that the two limbs adopt not only an angle of 90°, but also an angle of 180° relative to one another. In this way, the angled region can be configured so as to be more sharp-edged, and the guide rail can be produced with a more compact design.
A particular advantage of the invention lies in the fact that by the proposed measure, the flat running surfaces of the guide rails provided for the contact with the rolling bodies can be enlarged. Therefore, while maintaining the size of the guide rail, wider rolling bodies can be utilized and, as a result, the occurring forces can be distributed over a larger area. In this way, the stability and the loading capacity of the drawer pull-out guide can be additionally improved.
Thereby, the first limb and/or the second limb has or have a predetermined first material thickness, and the material diminution formed by the recess of the angled region has a reduced second material thickness in relation to the first material thickness. The definition “first material thickness” relates to the thickness of the raw material of the guide rail, without considering possible embossments or bends of the guide rail.
The at least one recess can extend at least over a region, preferably over substantially an entire length of the guide rail, in the longitudinal direction of the guide rail. Thereby, the recess is configured as a groove.
According to an embodiment, the first limb and the second limb, in a region outside the recess, bear against one another at least over a region. This is, in particular, the case when the two limbs are angled relative to one another by 180°.
The drawer pull-out guide according to the invention is characterized by at least one guide rail of the described type. The drawer pull-out guide includes a first guide rail configured to be fixed to a furniture carcass, and at least one second guide rail displaceably supported relative to the first guide rail. At least one rolling body is arranged between the first guide rail and the second guide rail, and the at least one rolling body is configured to run along the first limb or on the second limb of a guide rail.
The method according to the invention for producing a guide rail for a drawer pull-out guide is characterized by the following steps:
- a longitudinally extending material strand is provided,
- at least one recess in the form of a material diminution is inserted in the material strand, preferably by a roll forming operation, the at least one recess extending in the longitudinal extension of the material strand,
- the material strand is deformed or bent in the region of the recess, whereby a first limb and a second limb angled from the first limb are formed, and the recess is arranged in an angled region enclosed by the first limb and by the second limb.
BRIEF DESCRIPTION OF THE DRAWINGS
Further details and advantages of the invention will be explained in the following description of figures, in which:
FIG. 1 is a perspective view of an item of furniture comprising a furniture carcass and drawers displaceably supported relative thereto,
FIG. 2a, 2b show the drawer pull-out guide in an exploded view and in a cross-sectional view,
FIG. 3a, 3b show a comparison between a guide rail according to the prior art and a guide rail according to the invention,
FIG. 4a, 4b show a flat material strand with inserted recesses and the guide rail as a finished product.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an item of furniture 1 having a cupboard-shaped furniture carcass 2, and drawers 3 are displaceably supported relative to the furniture carcass 2 by drawer pull-out guides 4. Each of the drawers 3 includes a front panel 5, a drawer bottom 6, drawer sidewalls 7 and a rear wall 8. Each of the drawer pull-out guides 4 includes a first guide rail 9 (carcass rail) configured to be fixed to the furniture carcass 2 by fastening portions 12a, 12b, and a third guide rail 11 (drawer rail) displaceably supported relative to the first guide rail 9, the third guide rail 11 being connected or being configured to be connected to the drawer sidewall 7. Optionally, a second guide rail 10 (central rail) may be provided, the second rail 10 being displaceably supported between the first guide rail 9 and the third guide rail 11 so as to allow the drawer 3 to be fully extended.
FIG. 2a shows an exploded view of the drawer pull-out guide 4 with the first guide rail 9 (carcass rail) to be fixed to the furniture carcass 2, the third guide rail 11 (drawer rail) to be connected to the drawer 3, and with the second guide rail 10 (central rail) displaceably supported between the first guide rail 9 and the third guide rail 11. The first guide rail 9 includes two fastening portions 12a, 12b spaced from each other in the longitudinal direction (L), the first guide rail 9 being configured to be mounted to the furniture carcass 2 by the fastening portions 12a, 12b. At least one first running carriage 13 having a plurality of rolling bodies 14, 15 is displaceably supported between the first guide rail 9 and the second guide rail 10. The rolling bodies 14 are spaced from each other in the longitudinal direction (L), and each of the rolling bodies 14 has a rotational axis extending horizontally in the mounted position. On the contrary, each of the rolling bodies 15 has a vertically extending rotational axis in the mounted position. By a spring-assisted retraction device 16, the third guide rail 11 can be retracted into the closed end position at the end of the closing movement, and the spring-assisted closing movement can be decelerated by a damping device 17, for example in the form of a hydraulic piston-cylinder-unit.
FIG. 2b shows the drawer pull-out guide 4 in a cross-sectional view, in which the first running carriage 13 with the rolling bodies 14, 15 is supported between the first guide rail 9 and the second guide rail 10. At least one second running carriage 18 having rolling bodies 14a, 15a is displaceably supported between the second guide rail 10 and the third guide rail 11. Each of the rolling bodies 14a has a rotational axis extending horizontally in the mounted position, whereas the rolling bodies 15a are configured to be rotated about a vertically extending rotational axis in the mounted position.
Taking the example of the second guide rail 10, the invention will now be explained in greater detail. The second guide rail 10 includes a first limb 10a and at least one second limb 10b, the first limb 10a and the second limb 10b being connected to one another by an angled region 23. The angled region 23 includes a material diminution formed by a recess 21 extending along the angled region 23. Each of the first limb 10a and/or the second limb 10b can have a predetermined first material thickness, whereas the angled region 23 enclosed by the two limbs 10a, 10b is provided with at least one recess 21, so that the angled region 23 has a reduced second material thickness in relation to the limbs 10a, 10b. As shown in FIG. 2b, the limbs 10a, 10b, due to the presence of the recess 21, can be angled to one another to a larger extent, without substantial compressive stress occurring on the inside of the angled region 23 when the second guide rail 10 is machined. In the shown figure, the limbs 10a, 10b are angled to one another by 180°. In a region outside the recess 21, the two limbs 10a, 10b at least partially bear against one another, preferably without the formation of a gap 19 (FIG. 3a). In this way, the constructional height of the second guide rail 10, in particular when a plurality of limbs 10a, 10b are arranged above one another, can be reduced. The guide rail 10 can also include two or more material diminutions formed by recesses 21, 21a, 21b. In the shown embodiment, the limbs arranged adjacent to the recesses 21a, 21b each adopt an angle of approximately 90° to one another.
FIG. 3a and FIG. 3b show a direct comparison between a guide rail 10 according to the prior art (FIG. 3a) and a guide rail 10 according to the invention (FIG. 3b). The guide rail 10 according to the prior art depicted in FIG. 3a has a constant material thickness M1, and the limbs 10a, 10b—due to the lacking recess 21—are spaced from each other in a height direction under the formation of a gap 19. This also leads to an increase in the height (H) of the guide rail 10. In FIG. 3a, the angled region 23 has round-shaped configuration. Moreover, only running surfaces B, C having a relatively small width are available for the rolling bodies 14, 15, 14a, 15a.
FIG. 3b, on the contrary, shows an embodiment of the guide rail 10 according to the invention. Due to the recesses 21, 21a, 21b, the material thickness M2 is reduced in comparison to the material thickness M1, so that the limbs 10a, 10b can be angled to one another to a stronger extent. This leads to the fact that the height H1 according to FIG. 3b is smaller than the height H according to FIG. 3a. The smaller height H1 thus leads to a (desired) reduced constructional height of the guide rail 10. Moreover, it is visible that the flat running surfaces B1, C1 for the rolling bodies 14, 15, 14a, 15a, in comparison with the flat surfaces B, C according to FIG. 3a, are significantly enlarged. In this way, rolling bodies 14, 15, 14a, 15a with an increased nominal width can be utilized, so that an improved support of the guide rails 10, 11 can be provided and the forces can be distributed over a larger area. The recesses 21, 21a, 21b, in a cross-section perpendicular to the longitudinal direction (L), can each include at least one concave portion 22. The sharp-edged angled regions 23 can be preferably produced by a roll forming operation. Roll forming (also known as roll profiling or cold rolling) is a continuous bending method in which a material strand 20 (FIG. 4a) of metal runs into a profiling machine, and the material strand 20 is reshaped in the profiling machine by numerous subsequent bending operations until the desired shape of cross-section is produced.
According to an embodiment, it can be provided that the at least one guide rail 10, in a mounted position of the drawer pull-out guide 4, includes a substantially vertically extending portion 24, and the first limb 10a protrudes transversely, preferably at a right angle, in a first direction from the vertically extending portion 24 of the guide rail 10. The second limb 10b protrudes transversely, preferably substantially at a right angle, from the vertically extending portion 24 in a second direction, opposing the first direction. Moreover, it can be provided that the first limb 10a and the second limb 10b of the at least one guide rail 10 are configured so as to have a different length. It can be preferably provided that the second limb 10b has a length being at least three times as long as a length of the first limb 10a.
Exemplary embodiments:
- the material thickness M1 lies between 0.5 mm and 3 mm, preferably between 1 mm and 2 mm,
- the reduced material thickness M2 lies between 0.3 mm and 2 mm, preferably between 0.7 mm and 1.5 mm,
- the reduced material thickness M2 is smaller than 0.75, preferably smaller than 0.5, multiplied with the material thickness M1,
- the width of the running surface B1 lies between 4 mm and 7 mm, preferably between 5 mm and 6 mm,
- the width of the running surface C1 lies between 2 mm and 5 mm, preferably between 3 mm and 4 mm.
FIG. 4a shows a longitudinally extending material strand 20, in which recesses 21, 21a, 21b are introduced in a first step, preferably by roll forming. Subsequently, the material strand 20 is deformed or bent in a region of the recesses 21, 21a, 21b, whereby at least one first limb 10a and at least one second limb 10b are formed, and the recesses 21, 21a, 21b are arranged in an angled region 23 enclosed by the first limb 10a and by the second limb 10b. In a further step, the limbs 10a, 10b can be profiled in a height direction such that the limbs 10a, 10b, in a region outside the recesses 21, 21a, 21b, at least partially bear against one another, until the guide rail 10 is eventually present as a finished product. If appropriate, each angled region 23 can also include two or more recesses 21, 21a, 21b.
The guide rail 10 can include a third limb 10c and a fourth limb 10d which are connected to one another by a second angled region 23a. The second angled region 23a can have a second material diminution formed by a second recess 21b. Likewise, the guide rail 10 can have a fifth limb 10e and a sixth limb 10f which are connected to one another by a third angled region 23b. The third angled region 23b can have a third material diminution formed by a third recess 21a. The limbs 10a, 10b, 10c, 10d, 10e, 10f arranged adjacent to one another can each be angled to one another by an angle of approximately 45°, 90° or 180°.
Patent Application
20200337457
