EP0662168B1 - Washing machine - Google Patents

Abstract

The invention relates to a washing machine with at least one drum (10) arranged to rotate about a spindle (12) and with bearings (22) to absorb the axial and radial forces occurring when the drum (10) is rotated; according to the invention, at least part of the bearings (22) has a swivel (32) with at least one roller (34) and a tipping system to give a tipping movement transverse to the axis about which the swivel turns, or the swivel has an additional roller (60), the axis of rotation of which runs transversely to that of the other roller (34) of the swivel (32). Thus the additional forces caused by wobbling of the washing machine drum during its movement are safely and easily absorbed so that the useful life of the bearing system is substantially increased and thus time-consuming and costly maintenance work is unnecessary.

Description

The invention relates to a washing machine with at least one drum rotatably arranged about an axis of rotation and with bearing devices which together serve to absorb the forces occurring axially and radially due to the movement of the drum.

Such washing machines (US 45 22 046, AT 335 956 and DE-OS 30 27 382) have long been available on the market as lot washing machines, for example, and are operated in the so-called single, double or tandem mode. These known washing machines, which are used in particular in large laundries and in the hospital to handle large amounts of laundry, have a plurality of rotatable drums arranged in a row, which are divided into individual sections for soaking, prewashing, main washing and rinsing the laundry. For the passage of the laundry items through the individual sections mentioned, a rotation of the drum through 360 ° is necessary, the laundry items being moved into the next drum by slipping; otherwise the drums are either at a standstill or swung back and forth. In order to extend the dwell time of a laundry item within a section, several drums can form a section.

All drums are firmly connected to each other and can be pivoted or rotated about a common axis of rotation. At the ends of the Washing machines and between the individual sections, which are formed from the drums, there are storage devices which together absorb the axially and radially acting forces. In addition, the individual drums face and towards the loading side towards elastic walls in the form of so-called membrane walls, which serve to absorb the loads that result from the fact that the individual drum axes do not coincide with the actual axis of rotation due to inaccuracies when assembling the machine. Despite these additional compensatory measures, when the drums are moved, they nevertheless tumble, which are also favored by the unbalance which arises when the items of laundry are moved within the drums, so that the resulting bearing forces quickly fail due to the resulting forces. Nothing changes here, even if low-maintenance roller bearings made of highly wear-resistant special plastic are used and the running surfaces of the drum bearing rings are made of extra-strong stainless steel. Due to the failure of the storage devices in the known washing machines, there are downtimes of the entire washing system and costly and time-consuming maintenance work, so that these large washing machines have so far not been able to assert themselves successfully on the market to the extent that would be possible.

AT-PS 335 956 discloses a steering stool which can be rotated about a pivot axis and which has two end wheels provided with pinions at the end which rotate the washing drum from the articulation point of the steering stool by means of a drive. This steering stool unit for driving the drum does not assume a storage or support function, but rather is intended to drive only individual drum segments of the overall drum system independently of one another.

Based on this prior art, the invention has for its object to provide a washing machine in which the disadvantages described above do not occur. A pertinent one The object is achieved by a washing machine with the features of claim 1.

Characterized in that according to the characterizing part of claim 1 in a washing machine at least a part of the bearing devices has a pivotable steering stool with at least one rotating roller, which is provided for a tilting movement transverse to its pivoting axis with a tilting device, or that the steering stool has another Has idler, whose axis of rotation extends transversely to the axis of rotation of the other idler of the steering stool, the additional forces occurring when moving the respective drum, which are caused by a tumbling process of the drum, are safely and easily absorbed. The usual bearing devices that may otherwise be used here, in particular for absorbing the radially acting forces, then do not have to absorb the additional forces caused by the tumbling process mentioned, so that, relieved of this, they have a considerably longer service life than in the known devices for storing the Washing drum.

With the solution according to the invention, which could also be used in single-drum washing machines, the membrane or elastically flexible wall mentioned in the case of a drum can be dispensed with, because even the wobbling that occurs increasingly with rigid drum walls is reliably absorbed by the bearing device according to the invention. Even when the washing machine is in a high load state, there is no longer any failure due to the storage devices. The washing machine according to the invention is therefore safe to operate and time-consuming and cost-intensive maintenance work is either omitted completely or is only necessary at longer intervals.

In a preferred embodiment, the tilting device has a pivot pin which extends through the center of the steering bolster and the free end of which is at least partially smaller Diameter than that of an associated sleeve of the steering stool. Because of this configuration, the steering stool only tilts when it is subjected to a corresponding force from the drum due to the wobbling process. The other bearing points in the form of idler rollers of the respective steering bolster are relieved by this arrangement, which extends their service life. In this case, the pivot pin preferably has inclined, in particular crowned, contact surfaces along which the tilting movement of the steering stool takes place transversely to its pivot axis.

It has thus turned out to be particularly space-saving if, in a preferred further or different embodiment of the washing machine according to the invention, the circulation roller arranged centrally on the steering stool is brought into contact with a rolling surface arranged on the end face of the drum.

Optimal load and force absorption results if there is at least one bearing device between each drum.

In a further particularly preferred embodiment of the washing machine according to the invention, each bearing device is connected to a central frame which at least partially encompasses the respective drum and which has two continuous longitudinal bars on both sides, to which the bearing devices engaging between the individual drums are articulated as part of at least one rocker arm. This ensures precise centering of each individual bearing device with respect to the central frame and each bearing device that is part of a rocker arm aligns itself with the respective drum.

Preferably, the storage devices arranged on the loading and unloading side with the two longitudinal spars of the central frame and all storage devices are also elastic Lanyard connected to the central frame. The latter allows mechanical decoupling of the metallic components from bearing devices with a central frame, which has good damping properties which, on the one hand, reduce the noise level during operation of the washing machine and, on the other hand, keep the wear on the parts that can be moved relative to one another low.

In a further particularly preferred embodiment of the washing machine according to the invention, the revolving roller arranged at the end on the steering stool rolls along a toothed ring on its loading and unloading side, which cooperates with a drive for rotating the respective drum. In this way, the drive torque can be supported via the steering bolster in a substantially vertical plane, so that the bearing devices are subjected to stressful bending moments, as is the case when the drive force is introduced outside this plane.

The drive preferably has two drive axes, which are arranged parallel and laterally to the axis of rotation of the respective drum and run in a horizontal plane with the same.

A good introduction of force on the part of the drive also results from the fact that each drive has only one drive belt, which is in engagement with the ring gear of the associated drum between the drive axes.

The service life for the respective drive belt is increased by means of at least one tensioning device, which has a damping, and an energy accumulator, which holds contact wheels arranged pivotably via a lever linkage in contact with the drive belt.

The washing machine according to the invention is explained in more detail below with reference to the drawing.

Fig.1

in vereinfachter, prinzipieller Darstellung eine Seitenansicht auf die erfindungsgemäße Waschmaschine;

Fig.2

die Stirnansicht auf die Waschmaschine gemäß der Fig.1 von der Be- oder Entladeseite her gesehen;

Fig.3a, 3b

einen Längsschnitt bzw. eine Draufsicht auf einen Lenkschemel, wie er in der Fig.2 gesehen rechts oben dargestellt ist;

Fig.4a, 4b

einen Längsschnitt bzw. eine Draufsicht auf einen Lenkschemel, wie er in Fig.2 gesehen rechts unten dargestellt ist;

Fig.5

eine Stirnansicht auf eine Trommel, und zwar wie sie sich zwischen den einzelnen Trommeln der Waschmaschine ergibt;

Fig.6

die Draufsicht auf einen Lenkschemel, wie er in der Fig.5 gesehen rechts unten dargestellt ist;

Fig.7

die elastische Lagerung der Schwinge gemäß Fig.5 an dem Zentralrahmen der Waschmaschine;

Fig.8

eine über ein Hebelgestänge schwenkbar angeordnete Spannvorrichtung.

Show it:

Fig. 1

in a simplified, basic representation, a side view of the washing machine according to the invention;

Fig. 2

the front view of the washing machine according to Figure 1 seen from the loading or unloading side;

3a, 3b

a longitudinal section or a plan view of a steering stool, as shown in Figure 2 shown at the top right;

Fig.4a, 4b

a longitudinal section or a plan view of a steering stool, as shown in Figure 2 shown bottom right;

Fig. 5

an end view of a drum, as it results between the individual drums of the washing machine;

Fig. 6

the top view of a steering stool, as shown in Figure 5 shown bottom right;

Fig. 7

the elastic mounting of the rocker according to Figure 5 on the central frame of the washing machine;

Fig. 8

a clamping device pivotally arranged via a lever linkage.

The washing machine according to FIG. 1 has three drums 10 arranged one behind the other. These can have different widths to form sections of different lengths, and in particular two or more drums 10 shown in FIG. All drums 10 can be moved together about an axis of rotation 12 and at the same time and in the same direction of rotation. The drums 10 are interconnected by means of cylindrical connecting pieces 14 and are open to the environment. For further transport of the respective item of laundry into the next drum 10, slides 16 are provided, which enable further transport when the drums 10 are fully rotated. The drums 10 are surrounded by a stationary housing 18, which prevents unwanted leakage of detergent and / or water into the environment. To stand up the washing machine, it is mounted in a central frame 20, which is shown in FIG. 1 only in a basic representation.

The drums 10 of the washing machine are rotatably supported via the connecting pieces 14 by means of bearing devices 22, the bearing devices 22 being arranged at the end on the loading side 24 and the unloading side 26 and between the individual drums 10. The drums 10 can also be provided on the loading side with a flexible and unloading side with a rigid end wall 28 or 30. In this regard, the bearing device 22 is designed as a fixed bearing on the loading side 24 and as a floating bearing on the unloading side 26. Each bearing device 22 has at least one pivotable steering stool 32, which has at least one free end of a rotating roller 34 which interacts directly with parts of the respective drum 10 or with the drum 10 during their movement. As shown in FIG. 2 in particular, four steering stools 32 are arranged diametrically to the axis of rotation 12 on the loading side 24 and the unloading side 26 of the washing machine and between the individual drums 10 each two steering bolsters 32. At the beginning and end of the washing machine, that is to say on the loading side 24 and the unloading side 26, the steering bolsters 32 are pivotally mounted on so-called burning parts 36, which in a material-saving manner form plates which are connected to the central frame 20.

The pair of steering bolsters 32 shown in the upper half of FIG. 2 differs from the steering bolster pair 32 shown below, which has two idler rollers 34 for each steering bolster 32. Depending on how the direction of rotation of the drum 10 will be, one or the other roller 34 will press more strongly against the movable parts of the drum 10 and thus absorb the radial forces that occur. Since the upper two steering bolsters 32 of the bearing device 22, as seen in FIG. 2, bear the main load of the drum 10 assigned to them, the two lower steering bolsters 32 can be designed in a simplified manner. This simplified interpretation can be seen in particular in FIGS. 4a and 4b. The lower steering stool 32 shown there has a sleeve 38 in which a pivot 42 is guided via one or more bushings 40 and is fixedly connected to the plate 36 by a screw connection 44. At the upper end of the steering stool 32, the rotating roller 34 is rotatably arranged, the rotatably mounted outer ring 46 of which has a concave curvature which is in contact with a convex ring of a ring gear 48. The other free end of the steering arm 32 is penetrated by an adjusting screw 50, which enables the position of the steering arm 32 relative to the plate 36 via a spacer sleeve 52. By means of the adjusting device 36, 50, 52, the play between the sleeve 38 can optionally be specified via one of the sleeves 40 with a snap ring 54 arranged at the free end of the pivot pin, the game being brought to zero in order to achieve the mentioned fixed bearing, so that the Steering stool 32 is no longer axially displaceable relative to the fixed plate 36, but is only held pivotably about the pivot 42. For support or production of this freedom from play, a spacer ring 56 can also be provided between the bush 40 and the snap ring 54, which is eliminated if one wishes to achieve a loose bearing, as is provided on the unloading side 26 of the washing machine. By means of a further adjusting screw 53, the respectively assigned roller 34 can be set against the spherical running surface of the ring gear 48 without play according to the circumstances. With increasing wear on the upper rollers 34, the backlash can be automatically maintained via the spring 55 (FIG. 4b) of the adjusting screw 53.

At the location of the fixed bearing on the loading side 24, the upper steering bolsters 32, as shown in FIGS. 3a and 3b, are formed with the proviso that the pivot 42 is axially free of play as well as in contact with the sleeve 38 as in the described embodiment according to Figures 4a and 4b. The illustration in FIGS. 3a and 3b relates to the storage provided for the discharge side 26. There is an axial play between the snap ring 54 and the sleeve 38, so that the associated steering bolster 32 can be moved axially. Furthermore, the pivot 42, which passes through the steering stool 32 in the center, has a smaller diameter at its free end than the inside diameter of the associated sleeve 38. The diameter of the pivot 42 can be reduced, as shown in particular in FIG. 3b, in such a way that the transverse to the Direction of travel of the drum 10 extending diameter range in contact with the inner diameter of the sleeve 38 and otherwise not. This results in a possible tilting movement of the steering subframe 32 as shown in FIG. 3b out of the drawing plane or into the drawing plane, so that the tilting axis runs transversely to the pivot axis of the steering subframe 32 within the drawing plane. In this way, wobbling movements of the drum arrangement can be safely absorbed and controlled on the side of the floating bearing. The mentioned tilting movement of the steering stool 32 is supported by the fact that the Pivot 42 has inclined, in particular crowned, contact surfaces 58.

In the case of the bearing devices 22 between the individual drums 10, the respective steering bolsters 32 have a further circulating roller 60 in the middle, the axis of rotation of which runs perpendicular to the rotational axis of the respective other circulating roller 34 of the steering bolster 32 and can be brought into contact with a rolling surface 62 arranged on the end of the drum 10 is. This can be formed from a rigid end wall 30 in each case. Preferably, however, the rolling surface 62, as shown in particular in FIG. 1, is formed from two ring surfaces which run centrally around the respective connecting piece 14 and which can be brought into contact with the outer peripheral surface 64 of the circulating roller 60.

As shown in FIG. 5 in particular, two steering bolsters 32 arranged in the lower half of the drums 10 support the drum 10 via the connecting piece 14, which is firmly connected to the end faces 28 and 30 of the drums 10 at this point. For this purpose, the respective steering bolster is pivotally articulated about the cylindrical pivot 42 on a support 66 which is fixedly connected to a crossbar 68 which forms a type of rocker arm with two articulated support beams 70 which run obliquely upwards. The rocker 66, 68, 70 is connected to two longitudinal bars 74 of the central frame 20 via an elastic connecting means in the form of rubber bushings 72. This ensures vibration-free running of the rotating rollers 34 and 60. As shown in FIG. 8 in particular, each rubber bushing 72, which is encompassed by the link carrier 70 of the rocker, is held by means of two eyebolts 76 which pass through the U-shaped longitudinal bar 74. Each rubber bushing 72 has disc springs 78 at the end and an adjusting screw 80 is penetrated by the adjusting screw 80 to adjust the rigidity of the overall system of rubber bushing 72 and disc springs 78, which in turn is extended at the ends by extensions of the two Eye bolts 76 is held. The setting is made such that the sleeves are relatively soft in the axial direction and are relatively rigid in their radial elasticity.

The bearing devices 22 arranged on the loading side 24 and the unloading side 26 are likewise connected to the two longitudinal bars 74 of the central frame 20 via the plates 36. In this case too, the bearing devices 22 are connected to the central frame 20 via elastic connecting means in the form of rubber bushings 72. Between the plates 36 and the respective associated longitudinal spar 74 there is a plate element 82 which is fixedly connected to the longitudinal spar 74 and elastically resiliently supports the plates 36 with the two pairs of steering stems 32 via the rubber bushings 72 attached to the ends.

As already indicated, on the loading side 24 and the unloading side 26, the rotating rollers 34, which are respectively arranged on the ends of the steering bolsters 32, roll along a ring gear 48, which cooperates with a drive 84 for rotating the respective drum 10. This drive 84 has two drive axes 86, which are arranged parallel and laterally to the axis of rotation 12 of the respective drum 10 and extend in a horizontal plane 88 with the same. In FIG. 2, the electric drive motors associated with the drive axles 86 have been omitted for the sake of simplicity and for better illustration. Rather, the drive pinions 90 are shown in FIG. 2, which are mounted rotatably about the respective drive axis 86 within the plates 36 assigned to them. Each of the two drives 84 arranged at the ends has a drive belt 92 which engages with the toothed ring 48 of the associated drum 10 between the drive axles 86. The drive belt 92 is guided around the two drive pinions 90 and, as a toothed belt, engages with the teeth of the toothed ring 48, which has a Intermediate wall 94 is fixedly connected to the connecting piece 14 and thus to the drum 10 assigned to it. For the engagement with the toothed belt 92, the ring gear 48 has two rows of teeth lying side by side (see Fig. 3a). The drive according to the invention can also have a ring gear with only one row of teeth.

For the drive or toothed belt 92, a tensioning device 96 is provided on both sides of the drum 10 between the ring gear 48 and the respective drive pinion 90, which has a damping in the form of two rubber buffers 98, the degree of damping of which is adjustable by means of adjusting screws 100. Furthermore, each tensioning device 96, which is mounted in the plate 36, has an energy accumulator in the form of an adjustable compression spring 102, which, via a lever linkage 104, holds contact wheels in the form of double toothed wheels 106 pivotably arranged in contact with the drive belt 92 (see FIG. 8 ).

The lever linkage 104 has two levers 108 which are pivotally mounted in the base plate 36 at one end via a rotary bushing 110 and which have the contact wheels 106 at their other end. The contact wheels 106 are also rotatably supported in support forks 112, the lower support fork 112 seen in FIG. 8 being supported on the spring 102, which in turn is supported on a curved plate profile 114 which laterally comprises both opposite contact wheels 106 and via the pretension the resilient spring 102 also determines the spacing of the contact wheels 106 from one another.

Due to the bearing device according to the invention, the elastic end walls 28 can also be dispensed with; rather, like the end walls 30 arranged on the unloading side, they can consist of an unyielding material. The under certain circumstances, wobbling movements of the individual drums 10, which are increasingly occurring, can then still be safely absorbed with the bearing devices according to the invention.

The respective steering bolster according to the preceding figures is essentially formed from a flat plate which has rounded ends, the radius of curvature of which corresponds to the radius of curvature of the idler rollers 34. These flat steering bolster plates can also have a kink at the location of the pivot axis, so that the pivot axis of the steering bolster is arranged in offset planes with respect to the axes of rotation of the idler rollers 34.

Claims (12)

1. Washing machine with at least one drum (10), which is disposed rotatably about a rotational axis (12) and has bearing devices (22), which, jointly, act to absorb forces which occur axially and radially owing to the movement of the drum (10), characterised in that at least one part of the mounting devices (22) comprises a riding bed (32) which may be rotated about a pivot axis and which has at least one rotatable roller (34), which is provided with a tilting device for a tilting movement transverse to the pivot axis thereof, or in that the riding bed comprises a further rotatable roller (60), the axis of rotation of which extends transverse to the rotational axis of the other rotatable roller (34) of the riding bed (32) in each case.
2. Washing machine according to Claim 1, characterised in that the tilting device comprises a pivot (42) which engages through the riding bed (32) in the centre and the free end of which has, at least in part, a diameter which is less than the one associated sleeve (38) of the riding bed (32).
3. Washing machine according to Claim 2, characterised in that the pivot (42) comprises appropriate, in particular spherical, abutment surfaces (58), along which the tilting movement of the riding bed is performed, transverse to the pivot axis.
4. Washing machine according to one of Claims 1 to 3, characterised in that the riding bed (32) comprises the further rotatable roller (60) in the centre thereof, which further rotatable roller can be brought into abutment with a rolling surface (62) which is disposed on the front face of the drum (10).
5. Washing machine according to one of Claims 1 to 4, characterised in that at least one bearing device (22) is provided between each drum (10).
6. Washing machine according to one of Claims 1 to 5, characterised in that each bearing device (22) is connected to a central frame (20), which surrounds, at least partially, the drum (10) in each case and which comprises two pehetrating longitudinal spars (74) on each side, on which spars the bearing devices (22) which engage between the individual drums (10) are articulated as part of at least one rocker (66, 68, 70).
7. Washing machine according to Claim 6, characterised in that the bearing devices (22) which are arranged on the loading side (24) and unloading side (26) thereof are likewise connected to the two longitudinal spars (74).
8. Washing machine according to Claim 7, characterised in that all bearing devices (22) are connected to the central frame (20) via resilient connection means (72).
9. Washing machine according to one of Claims 1 to 8, characterised in that one the loading side (24) and unloading side (26) thereof, the rotatable roller (34) which is disposed at the end on the riding bed (32) in each case, rolls along a sprocket wheel (48), which cooperates with a drive (84) to rotate of the drum in each case.
10. Washing machine according to Claim 9, characterised in that the drive (84) comprises two drive axes (86) which are disposed parallel to one another and lateral to the axis of rotation (12) of the drum (10) in each case and extend in a horizontal plane (88) thereof.
11. Washing machine according to Claim 10, characterised in that each drive (84) comprises a driving belt (92), which is in engagement with the sprocket wheel (48) of the associated drum (10) between the drive axes (86).
12. Washing machine according to Claim 11, characterised in that at least one tensionning device (96) is provided for the driving belt (91), which tensionning device has both a damping and an energy accumulating device (102), which holds abutment wheels (106), which are arranged in a pivoting manner via a lever rod (104), in abutment with the driving belt (92).

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