Patent Application
20110074263
The present invention relates to a household appliance, in particular a refrigeration appliance such as a refrigerator, with a door that can tilt about a tilt axis, and with a braking device for damping the tilt motion of the door.
In the case of household appliances, in particular such as refrigerators, the provision of so-called door-in-door-solutions is increasingly called for as a means of improving energy efficiency, in which an additional door is provided in the actual door of the refrigerator, such as for example of a refrigerator, in order to enable access to a drinks compartment or to a rack for drinks attached to the inside face of the main doors independently of opening of the “main doors”. As in the case of such solutions it is no longer necessary to open the main doors and warm air can thereby no longer flow into the refrigerator, less cooling power and thus less energy is required overall.
In order not to spoil the esthetics of such door-in-door solutions by the addition of a further handle, the smaller door arranged within the main doors is generally provided with a so-called push-push mechanism, in the case of which both opening of the door and its closure by means of simple pressure exerted on the edge region of the door, for example by the hand of a user. A spring is as a rule required for functioning of the push-push mechanism, which effects or at least assists the autonomous opening of the door from its closed position—in opposition to the direction of pressure exerted by the hand. This can, however, lead to problems in that as it is not firmly held by a user by means of a handle, the door performs an uncontrolled and excessively rapid movement. This problem then arises in particular if the tilt axis of the door is arranged horizontally, and the movement of the door increases in force upon opening as a result of gravity. In order to prevent an excessively rapid movement of this kind, U.S. Pat. No. 7,059,693 B2 proposes the attachment of a damping unit to the door, in which a rotating element in an oil-filled container serves to damp the movement of the door. In practice, however, is has proved difficult to mount a damping unit to act on the door, in light of the restricted space available.
The present invention is based on the problem of avoiding the problem associated with the prior art, and creating a household appliance, such as, in particular, a refrigerator, in which a damping unit or braking device for damping the tilt motion of the door provided, which not only works reliably, but can also be readily installed, despite the limited space available.
This problem is solved with a household appliance according to claim 1. Advantageous developments of the invention are the subject of the dependent claims.
The inventive household appliance comprises a door which can be tilted about a tilt axis and a braking device for damping the tilt motion of the door. The invention is characterized in that a transferring unit for transferring the rotation of the tilt axis to a braking axis during the tilt motion of the door is provided, said braking axis being offset relative to the tilt axis, and that the braking device is here in functional cooperation with the braking axis. In other words the braking device does not act directly on the door, but on the transferring unit. The braking device can thereby be installed in a position optimally tailored to the prevailing space, which would otherwise be particularly difficult to realize in the immediate vicinity of the moving door. It should here be noted that the terms “tilt axis” and “braking axis” should not simply be understood as to refer to the actual physical embodiment of such an axis, for example in the form of a shaft, but that they are to be understood in the abstract sense of the word “axis”. This means that any form of the embodiment of such an axis should be encompassed by these terms, so that the rotational motion of the door is transferred from its tilt axis to another axis designated as the braking axis, and the braking device acts on this braking axis.
A particularly simple embodiment of the invention then arises if the tilt axis comprises a pin or for example two pins at the end of the door, and the transferring unit is made up of a multiplicity of toothed wheels, the first of which is connected in a torque-free or non-slip manner with one of the pins and the last of which is connected in a torque-free manner to the braking device. Such an embodiment is easily realizable from the mechanical perspective and cheap to manufacture, as the toothed wheels are available off the shelf and are thus reasonably priced.
The braking effect can be apportioned particularly effectively, if the last toothed wheel is placed underneath the first toothed wheel; in other words the last toothed wheel has a greater pitch circle than the first toothed wheel.
An alternative possible realization of the transferring unit takes the form of a universal joint, one end of which is connected in a torque-free manner with a pin as part of the tilt axis and whose other end is connected in a torque-free manner to the braking device.
It is also possible to embody the transferring unit as a belt drive with two belt pulleys and a belt, in which a first belt pulley is connected in a torque-free manner with one pin as part of the tilt axis and a second belt pulley is connected to the braking device in a torque-free manner.
It is particularly preferable to embody the tilt axis in the form of at least one pin connected to the door in a torque-free manner and thereby mounting the door in a pivotable manner on a frame of the household appliance. The transferring unit and the braking device acting on the pin or pins are here located outside the door.
It is alternatively possible to arrange the transferring unit and the braking device with the brake within a cavity inside the door. In order then to be able to mount the door on a frame, the at least one pin forming the tilt axis is preferably connected to the frame in a torque-free manner. With this embodiment it is thus possible to use the space within the door to accommodate the transferring unit and the braking device.
A particularly expedient application of the invention then emerges if the door is built into an even larger door—also known as a main door—of the household appliance, where the larger door can tilt preferably about a essentially vertically arranged door tilt axis. This larger door is, for example, a “normal” door of a freezer or refrigerator, which is laterally jointed. It is here particularly advantageous if the tilt axis of the small door is essentially horizontally arranged, and the door is thus opened by being swung downwards. In this case “essentially” vertically or horizontally mean only that the precise alignment in a particular orientation is not the critical factor, but that tolerances stemming from manufacture or uneven setting-up of the appliance concerned may apply, without this impairing the functional capability of the invention.
The present invention is then simple to realize, if the transferring unit acts upon the tilt axis of the door, and not on a point offset relative to the tilt axis. Accordingly in this embodiment only the rotational movement need be transferred and it is not necessary also to transfer or compensate translation components, as would be the case were the transferring unit to act upon a point outside the tilt axis.
A particularly simple, reliably operating and cost-effective braking device is produced by a friction-braked piston movable within a cylinder. Braking devices of this kind are available on the mass market and are, for example, manufactured by ITW-Ateco GmbH. In the case of such braking devices a piston made out of for example Minlon® rotates in a housing manufactured for example from Delrin®, damped by the viscosity of a liquid introduced between the two.
Further advantages, features and characteristics of the invention are evident from the following description of an advantageous embodiment of the invention. Where:
a-3k show different components of the embodiment from
By way of example of the invention there follows a description of a refrigerator with a side-hinged door, into which is built a smaller, additional door, which can be opened and closed in a pivotable manner about a horizontally arranged tilt axis.
It is evident from
In this embodiment the braking device 20 comprises a piston 28, which can move in a cylinder 27 and is braked through friction. The piston 28 here has engaging projections 26, which engage in recesses 37b of the last toothed wheel 37 (cf.
By means of the previously described arrangement, upon rotation of the pin 15 connected to the door 12, this rotational movement, which is forced through opening of the door 12 by means of the torsion spring 60, is transferred by means of the toothed wheels 34-37 from the tilt axis 14 running through the pin 15 to the braking axis 22 running beneath said tilt axis 14, which passes centrally through the last toothed wheel 37. The braking device 20 with the piston 28 rotating in the cylinder 27 here lies exactly on the braking axis 22 and thus acts on the rotational movement of the fourth toothed wheel 37 or the braking axis 22 respectively. Through appropriate selection of the pre-tensioning of the torsion spring 60 and the damping characteristics of the braking device 20, the arrangement can here be configured in such a way that—after the torsion spring 60 ceases to have an effect as the opening movement of the door 12 progresses and the force of gravity exerts an increasingly greater effect as the door opens ever wider—an uncontrolled, excessively rapid downward movement of the door 12 can be avoided. As the braking device 20 does not or need not act directly on the tilt axis 14 of the pin 15 or door 12, but can also exercise its function on a position offset relative to the tilt axis 14, where space conditions are correspondingly more favorable in form, the total room available can be better used, and the arrangement optimized. A typical example of the cylinder 27 of the braking device 20 is some 50 mm long and has a diameter of 20 mm.
As is evident from
The frame 40 can be embodied in such a way that it forms a housing 42 (cf.
Instead of embodying the transferring unit 30 already described in the form of toothed wheels 34-37, a universal joint or a belt drive with two or more belt pulleys and corresponding belts can also be provided, whereby in an appropriate manner the rotational or tilt motion of the door 12 can be transferred from its tilt axis 14 to a braking axis 22 at a distance from this.
For practical purposes, diecast zinc should be mentioned as a particularly suitable material for the first toothed wheel 34, while the remaining toothed wheels and the other components are preferably manufactured from POM (polyoxymethylene). These components can of course also be produced from milled steel parts or appropriate plastics, if applicable reinforced with glass fiber.
A refrigerator with left-hinged large door and bottom-hinged small door was previously specified as an example of a household appliance according to the invention. The invention can of course also be used in other types of household appliances, in which such a door-in-door or similar arrangement is desired.
It should be recorded that the features of the invention, such as for example the design, shape and material of the transferring unit and the braking device as well as their arrangement described with reference to the embodiment represented can also be present in the case of other embodiments, except if otherwise specified or not feasible on technical grounds.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2008 026 383.4 | Jun 2008 | DE | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP2009/056721 | 6/2/2009 | WO | 00 | 12/1/2010 |
