EP1602317B1 - Snap-in bushing with protection against disconnection. - Google Patents

Description

The invention relates to a bushing for a rail roller for transporting a dish rack in a dishwasher, wherein the bushing is supported by a free, horizontally angled end of a dish rack projecting away wire bracket, which projects into a horizontal bore in a roller-side running portion of the liner, which serves horizontal axis of rotation for the rail roller, wherein outside the bore of the running portion in the region of the inlet opening an at least partially elastic latching device for clamping receiving a free end of the wireframe bent substantially perpendicular portion of the hanger wire is provided on the liner, and wherein the locking device in mounted state this section of the hanger wire at least over part of its circumference clasps.

Such liners have long been used as functional elements in dishwashers. They carry the rail rollers for moving the dish rack in the dishwasher, the latter being secured to the respective bushings by way of wire hangers projecting upwardly or laterally from the dish rack, which are each angled horizontally at their ends, which in turn on two rails on both sides of the dish rack carry running rail rollers.

Usually, the known liners are provided with a horizontally extending bore in the mounted state in its roller-side, the rollers carrying running section, into which projects the free angled horizontal end of the respective wire bracket. For fixed support of the bushing on the wire also a locking device in the region of the inlet opening of the bore of the barrel section is provided with which a respect to the free end of the wire bracket at right angles angled portion of the hanger wire is firmly clamped in the mounted state. The known locking device usually consists of two on both sides of the male wire hanger portion arranged staple jaws, between which is pressed during assembly of the corresponding portion of the hanger wire, wherein the two clamp jaws yield resiliently and then clasp the wire hanger due to their spring force.

After this latching occurs, however, especially in the occurrence of axially extending in the direction of the horizontal bore of the barrel section forces that the catch association is untapped. The seated roller liner is then no longer securely attached to the wire hanger and may possibly fall down as the crockery basket moves, placing the basket in an "imbalance" position.

To prevent this, the latching device was provided with further developments of the known liner with a hook, which must be specially screwed during assembly. Although the hook then includes large parts of the circumference of the portion of the wire bracket to be clamped, so Unwrapping becomes impossible. Such a liner is from the document DE 4417236 A known. However, a disadvantage is the considerably more complicated assembly process, because instead of a single direction of movement as when pressing the wire clip portion to be clamped between the two symmetrical clamp jaws of the locking device now at least two directions of movement during assembly are required, which more than doubles the assembly time. With an annual production of several hundred million such liners worldwide, this increase in assembly time is a considerable cost factor.

Object of the present invention is in contrast to further develop the bushing initially described, that on the one hand a subsequent unwinding of the mounted on the wire hanger bushing is reliably prevented, on the other hand, however, only a single assembly movement is necessary.

According to the invention, this object is achieved in an equally surprisingly simple and effective manner in that the latching device has an enclosing hook and a relative to the umklammernden portion of the stirrup wire the Umschließungshaken oppositely arranged insertion ramp, which is spaced by an oblique separation gap from the Umschließungshaken, wherein the oblique Separating gap between two substantially mutually parallel surfaces of the Umschließungshakens on the one hand and the insertion ramp on the other hand is formed, and wherein the surface normals of these surfaces intersect at a different angle from 90 ° a direction parallel to the longitudinal direction of the portion to be clamped the stirrup wire.

During assembly, the bushing according to the invention simply has to be pressed over the oblique separating gap in an axial direction with respect to the bore in the running section to the crockery basket onto the corresponding section of the hanger wire. In this case, automatically takes place via the insertion ramp due to the geometric design of a rotation, and the liner is located after the engagement of the hanger wire section in the Inventively designed locking device without further assembly movement in its final position. A second movement in a further direction of movement, as in the above-described improved solution according to the prior art, which would require more than twice the assembly time, is no longer necessary in this case. In addition, the mounting device can be made mechanically much easier.

A particularly preferred embodiment of the liner according to the invention is characterized in that the angle between the surface normals of the oblique separating gap forming surfaces and the direction parallel to the longitudinal direction of the portion to be clamped of the hanger wire between 30 ° and 80 °, preferably about 45 °. With this design, on the one hand, a high level of security is achieved against unintentional uncoupling of the assembled strap wire section from the latching device, on the other hand, the devices required for the assembly can be made mechanically particularly simple.

Also preferred is an embodiment of the bushing according to the invention, in which the enclosing hook surrounds a larger radial region of the section of the stirrup wire to be clasped than the insertion ramp, preferably a circumferential angle of more than 90 ° of the wire circumference, in particular more than 180 °. In this way, a particularly secure mounting of the portion of the stirrup wire to be clamped in the latching device is ensured.

In order to prevent an unintentional untangling of the wire hanger portion even more effective, in a development of this embodiment, the Umschließungshaken on the opposite to the insertion ramp lower elasticity.

This can be achieved particularly easily by the fact that the lower elasticity of the enclosing hook by a respect to the Insertion ramp thicker wall thickness and / or greater stiffness of the enclosing hook is effected.

Particularly preferred is also an embodiment of the bushing according to the invention, in which the enclosing hook and the insertion ramp of the latching device are integrally connected to the running section. Because the bushing is a mass-produced article, the one-piece method of manufacture is required for economic reasons, since retrofitting a multipurpose bushing would unacceptably increase the price of the product.

In an economically particularly favorable manner, the liner according to the invention can be manufactured as an injection molded part.

Here again, the structure of the liner made of an elastic plastic material is particularly cost.

In order to be suitable for use of the liner according to the invention in a dishwasher with thermal drying device, the elastic plastic material must have a temperature resistance up to at least 70 ° C, since such drying devices operate in simple dishwashers with temperatures of about 65 ° C. Preferably, the elastic plastic material for the liner according to the invention, however, have a temperature resistance of above 100 ° C, so that the liner can also be used in dishwashers in which a drying temperature of 95 ° C is driven.

As well suitable plastic materials for the liner according to the invention come polyamide or POM in question, since these materials also have a required for the locking device elasticity over the entire operating temperature range of a dishwasher.

As an alternative to the elastic plastic material, the bushing according to the invention may be made of metal in other embodiments but also for the purpose of a particularly high load capacity and durability, at least parts of the latching device must be designed resiliently.

Usually, the wire hanger of the dish rack to which the liners according to the invention are attached, provided with a plastic coating. Therefore, in order to avoid abrasion, it is advantageous if, in the case of the metal embodiment of the bushing according to the invention, a plastic coating is also provided at least in the area of the latching device, which can in particular also be color matched to the plastic coating of the wire hangers of the dishwashing basket.

Further features and advantages of the invention will become apparent from the following detailed description of embodiments of the invention with reference to the figures of the drawing, which shows details essential to the invention, and from the claims. The individual features may be implemented individually for themselves or for a plurality of combinations in variants of the invention.

In the schematic drawing embodiments of the invention are shown, which are explained in more detail in the following description.

Show it:

Fig. 1

a schematic spatial representation of an embodiment of the bushing according to the invention with engaged strap wire;

Fig. 2a

the liner of Figure 1 without the hanger wire.

Fig. 2b

a further embodiment of the bushing according to the invention with respect to the embodiment of Figure 2a in a different direction extending oblique separation gap.

Fig. 3a

a liner according to the prior art with staple jaws and attached rail roller;

Fig. 3b

a schematic representation of the liner according to the prior art according to Figure 3a without rail roller.

Fig. 4a

a highly schematic side view of another roller according to the prior art with hooks as a latching device; and

Fig. 4b

the bushing according to the prior art of FIG. 4a in a schematic view with an axial direction of view of the bore in the barrel section.

In Fig. 1 is a perspective schematic representation of an embodiment of the liner 1 according to the invention, which is to carry a rail roller 2, as shown in Fig. 3a at a bushing 1 "in the prior art. A wire bracket 3, which by a In the drawing, not shown dish rack of a dishwasher, is bent at its free end approximately at right angles and protrudes with this free end in a hole 4 in a roller-side barrel section 5 of the bushing 1. To attach the wire clip 3 in the region of a section 6 is at the 1 comprises a latching device according to the invention, which has an enclosing hook 7 , and an insertion ramp 8 arranged opposite the enclosing hook 7 with respect to the section 6 of the wire clip 3 to be clamped zwe i substantially parallel surfaces 10 of the Enclosing hook 7 on the one hand and the insertion ramp 8 on the other hand is formed.

From FIGS. 2 a and 2 b, which show equivalent embodiments of the bush 1 and 1 'according to the invention without tied wire clips 3, it is clear that the surface normals of the opposing surfaces 10, 10' are at a direction deviating from 90 ° in a direction parallel to the longitudinal direction of the to clinging section 6 of the hanger wire 3 cut. Preferably, this angle will be approximately between 30 ° and 80 °, in particular at approximately 45 °. In the embodiment of the bushing 1 'according to FIG. 2b, the enclosing hooks 7' and the insertion ramp 8 'are rotated by 180 ° relative to the embodiment according to FIG. 2a, so that the surfaces 10' lying parallel to one another extend correspondingly rotated by 90 ° include oblique separation gap 9 '.

As already mentioned above, a prior art bushing 1 "is shown in Fig. 3a, in which the latching device for accommodating the section 6 of a wire clip 3 consists of two symmetrical clamping jaws 7", 8 "Fig. 3b shows the bushing 1 "according to Fig. 3a without patch rail roller 2 in analogy to the representation of the bushing 1 according to the invention shown in FIG. 1st

Figures 4a and 4b show very schematically a bushing 1 '"according to the prior art with attached wire hanger 3, wherein the locking device consists of a hook 7'" with the disadvantages described above during assembly.

Claims (12)

1. Runner bushing for a track roller (2) for moving a crockery basket in a dishwasher, the runner bushing being carried by the free end of a horizontally bent wire bracket (3) which projects away from the crockery basket and projects into a horizontal bore (4) in a runner section (5) of the runner bushing at the roller side, the runner section (5) acting as a horizontal axle for the track roller (2), a latch arrangement which is resilient at least in part being provided on the runner bushing exteriorly of the bore (4) of the runner section (5) in the region of its entry opening, the latch arrangement being for the clamped reception of a section (6) of the wire bracket (3) which is bent essentially at a right angle with respect to the free end of the wire bracket (3), and the latch arrangement in the assembled state clamping this section (6) of the wire bracket (3) at least along part of its circumference, characterised in that the latch arrangement has an embracing hook (7; 7'), and also, relative to the section (6) of the wire bracket (3) that is to be clamped, a lead-in ramp (8; 8'), arranged opposite the embracing hook (7; 7'), the lead-in ramp (8; 8') being spaced by an oblique separating gap (9; 9') from the embracing hook (7; 7'), and the oblique separating gap (9; 9') being formed between two surfaces (10; 10') which extend essentially parallel to one another, namely on the one hand that of the embracing hook (7; 7'), and on the other hand that of the lead-in ramp (8; 8'), and the perpendiculars to these surfaces (10; 10') intersecting a direction that is parallel to the longitudinal direction of the section (6) of the wire bracket (3) that is to be clamped, namely intersecting it at an angle which differs from 90°.
2. Runner bushing according to claim 1, characterised in that the angle between the perpendiculars to the surfaces (10; 10') that form the oblique separating gap (9; 9'), and the direction parallel to the longitudinal direction of the section (6) of the wire bracket (3) that is to be clamped, amounts to between 30° and 80°, amounting preferably to approximately 45°.
3. Runner bushing according to one of the preceding claims, characterised in that the embracing hook (7; 7') encircles a greater radial region of the section (6) of the wire bracket (3) that is to be clamped, than the lead-in ramp (8; 8'), being preferably a circumferential angle of more than 90° of the wire circumference.
4. Runner bushing according to claim 3, characterised in that the embracing hook (7; 7') has lower resiliency as compared to the lead-in ramp (8; 8').
5. Runner bushing according to claim 4, characterised in that the lower resiliency of the embracing hook (7; 7') is brought about by a greater wall thickness as compared to the lead-in ramp (8; 8') and/or greater shape rigidity of the embracing hook (7; 7').
6. Runner bushing according to one of the preceding claims, characterised in that the embracing hook (7; 7') and the lead-in ramp (8; 8') of the latch arrangement are connected monolithically with the runner section (5).
7. Runner bushing according to claim 6, characterised in that the runner bushing (1; 1') is made as an injection moulding.
8. Runner bushing according claim 7, characterised in that the runner bushing (1; 1') is constructed from resilient plastics material.
9. Runner bushing according to claim 8, characterised in that the resilient plastics material has thermal stability up to at least 70°C, preferably to in excess of 100°C.
10. Runner bushing according to one of claims 8 and 9, characterised in that the resilient plastics material contains polyamide or POM.
11. Runner bushing according to one of claims 1 to 6, characterised in that the runner bushing (1; 1') is made of metal, parts of the latch arrangement having spring action.
12. Runner bushing according to claim 11, characterised in that the runner bushing (1; 1') has a plastic coating, at least in the region of the latch arrangement.

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