Friction damper, and a laundry appliance equipped with the friction damper

Abstract

The invention relates to a friction damper (8) comprising: - a damper rod (9), which has a first frictional surface (18), wherein the damper rod (9) extends in a rod longitudinal direction (11); -a damper main part (10), the damper main part (10) comprising: + a rod receptacle (19) for receiving the damper rod (9), wherein a second frictional surface (20) for interacting with the first frictional surface (18) is arranged in the rod receptacle (19), wherein the damper rod (9) is received in the rod receptacle (19) so as to be displaceable in the rod longitudinal direction (11); + a coil (22) for generating a magnetic field, wherein the coil (22) is designed to change the contact-pressure force of the first frictional surface (18) and the second frictional surface (20) against each other. The damper rod (9) has a polygonal cross section, wherein the first frictional surface (18) is formed on a side face (21) of the damper rod (9).

Description

[0001] FRICTION DAMPER, AS WELL AS A WASHING APPLIANCE EQUIPPED WITH THE FRICTION DAMPER

[0002] The invention relates to a friction damper and a laundry appliance equipped with the friction damper. The laundry appliance can be a washing machine, a tumble dryer, or a washer-dryer combination.

[0003] Generally, a washing machine performs washing, rinsing, and dehydration operations by filling the lower part of the interior of a drum tub with water and detergent, placing the laundry into a laundry drum installed in the drum tub, and rotating the laundry drum.

[0004] Such a washing machine is a device for removing dirt from laundry using a suitable detergent and mechanical force.

[0005] A tumble dryer can have a similar design to a washing machine. The dryer is used to remove moisture from laundry.

[0006] There are also combined appliances consisting of a washing machine and a tumble dryer, which can be referred to as a washer-dryer combination.

[0007] The umbrella term for all these devices is laundry appliance.

[0008] Due to the rotation of the washing drum and the mass of the laundry contained within it, the imbalance of the laundry or the wash water in laundry appliances can cause oscillating movements of the washing drum or, associated with it, the drum tub. These oscillating movements of the washing drum can be dampened by a friction damper. The friction damper can convert the kinetic energy into heat through friction by moving a first friction surface relative to a second friction surface.

[0009] DE102005032499B4 discloses a damper for vibration damping and a washing machine equipped with the same. The damper includes a damper cylinder; a shaft inserted into the damper cylinder through one end of the damper cylinder, which reciprocates in the longitudinal direction of the damper cylinder; and a friction element provided on the shaft for damping the vibration generated by friction with the inner wall of the damper cylinder, which friction element moves perpendicular to the longitudinal direction of the damper cylinder. The damper adjusts its damping force according to the vibration conditions of an object to be vibrated and has an improved vibration-damping effect.

[0010] The damper known from DE102005032499B4 has a complex structure and is therefore highly susceptible to errors.

[0011] The object of the present invention was to overcome the disadvantages of the prior art and to provide an improved friction damper as well as a laundry appliance equipped with the improved friction damper.

[0012] This object is achieved by a friction damper and a laundry appliance equipped with the improved friction damper according to the claims.

[0013] According to the invention, a friction damper is designed. The friction damper comprises:

[0014] - a damper rod having a first friction surface, the damper rod extending in a rod longitudinal direction;

[0015] - a damper main part, the damper main part comprising:

[0016] + a rod holder for receiving the damper rod, wherein a second friction surface for interacting with the first friction surface is arranged in the rod holder, wherein the damper rod is received in the rod holder so as to be displaceable in the rod longitudinal direction;

[0017] + a coil for generating a magnetic field, wherein the coil is designed to change the contact force of the first friction surface and the second friction surface against each other.

[0018] The damper rod has a polygonal cross-section, wherein the first friction surface is formed on a side surface of the damper rod.

[0019] A polygonal cross-section of the damper rod within the meaning of this document can be a cross-section that has multiple side surfaces or multiple corners. This can be, for example, a triangular cross-section, a rectangular cross-section, or even a trapezoidal cross-section. The corners of the cross-section do not necessarily have to be sharp-edged. Rather, it is also conceivable for the corners of the cross-section to be rounded. The cross-section of the damper rod is formed on a plane that lies at a right angle to the longitudinal direction of the rod. The friction damper according to the invention has the advantage of a simple structure and, due to this simple structure, a low susceptibility to failure and thus good functionality.

[0020] In a first embodiment variant, it can be provided that in the energized state of the coil, the contact force of the first friction surface and the second friction surface against each other is higher than in the de-energized state of the coil.

[0021] In a second embodiment, it can be provided that the first friction surface and the second friction surface are pressed against each other by a spring force and that in the energized state of the coil, the contact force of the first friction surface and the second friction surface against each other is lower than in the de-energized state of the coil.

[0022] Furthermore, it can be expedient if the coil has a coil axis, wherein the coil axis is arranged at a right angle to the longitudinal direction of the rod, wherein an iron core is formed which is embedded in the coil. This has the advantage that this measure allows the damper rod to be attracted directly to a contact surface of the rod holder in order to increase the frictional force between the first friction surface and the second friction surface. In other words, a force can thus be exerted on the damper rod transversely to the longitudinal direction of the rod. Thus, the normal force between the first friction surface and the second friction surface can be varied, whereby the frictional force of the first friction surface and the second friction surface can be influenced.

[0023] Furthermore, the coil can be provided with a coil axis, wherein the coil axis is arranged at a right angle to the longitudinal direction of the rod, with the coil axis being straight. This has the advantage that this measure allows the coil to have an efficient design. In particular, it can be provided that the coil winding is arranged on a side of the damper rod on which the first friction surface is arranged. The coil can have a compact winding and be arranged completely next to the damper rod.

[0024] In particular, it can be provided that the iron core is arranged on one side of the damper rod. The iron core can be arranged next to the damper rod. Furthermore, it can be provided that the coil has a coil winding that is hollow-cylindrical in cross-section. This has the advantage that this measure allows the coil to have an efficient design.

[0025] Furthermore, it can be provided that the first friction surface is arranged in a plane and that the coil has a coil winding wound around the coil axis, wherein the coil axis is arranged at a right angle to the first friction surface. This offers the advantage that the friction damper can have a simple structure and thus offer high reliability.

[0026] Furthermore, it can be provided that the coil axis intersects the first friction surface. This has the advantage that the force applied to change the contact force of the first friction surface and the second friction surface can be applied directly and efficiently.

[0027] Furthermore, it can be provided that the damper rod has a rod width and a rod thickness, wherein the rod width corresponds to a multiple of the rod thickness, wherein the first friction surface is arranged on the side surface extending in the rod width, and the coil is arranged entirely adjacent to the side surface. This has the advantage that, through this measure, the force can be applied directly and efficiently to change the contact force of the first friction surface and the second friction surface.

[0028] Furthermore, it can be provided that the damper rod is made of a ferromagnetic material, and the coil and the damper rod are positioned relative to each other in such a way that, when the coil is energized, a magnetic flux from the coil flows through the damper rod. This has the advantage that this measure allows for a simple design for increasing the friction force.

[0029] In addition, a friction lining can be arranged between the iron core and the damper rod. This measure can increase the friction effect.

[0030] Furthermore, it can be provided that an armature disk is formed which is arranged between the coil and the damper rod, wherein the armature disk is coupled to a counter-disk by means of a coupling rod, wherein the counter-disk is arranged on a side of the damper rod opposite the armature disk, wherein a friction lining is formed which is arranged between the iron core and the damper rod, wherein the second friction surface is formed on the friction lining, wherein when the armature disk is attracted to the coil by means of the magnetic field, the first friction surface of the damper rod is pressed against the second friction surface by means of the counter-disk. This has the advantage that such a design can have a simple structure and high effectiveness. In particular, with such a design the magnetic circuit can be closed via the iron core and the armature disk.The armature disk can be arranged at a small distance from the iron core when the second friction surface is in contact with the first friction surface, so that the air gap is as small as possible and the magnetic attraction force is thus as high as possible.

[0031] In a first embodiment, the coupling rod may be formed integrally with the armature disk. In a further embodiment, the coupling rod may be formed as a separate component coupled to the armature disk.

[0032] Furthermore, it can be provided that a third friction surface is formed on the damper rod opposite the first friction surface, and a fourth friction surface is formed on a second friction lining. The second friction lining is arranged on the counter-disk. When the armature disc is attracted to the coil, the damper rod is clamped between the friction lining and the second friction lining by means of the counter-disk. This measure can further increase the friction force.

[0033] Furthermore, it can be provided that the counter disc is attached to the coupling rod by means of fastening means. In particular, it can be provided that a thread is formed on the coupling rod and that the counter disc is screwed to the coupling rod by means of nuts.

[0034] Furthermore, the coupling rod can be guided through a damper rod recess in the damper rod. This offers the advantage that the coupling rod can be guided centrally through the damper rod.

[0035] Furthermore, the main damper component can be constructed in several parts, with the individual parts being coupled together in the area of ​​the damper rod. Another advantageous embodiment is one in which the friction lining can be made of a ferromagnetic material. This has the advantage that the friction lining does not interrupt the field lines and does not act like an air gap. This allows for an increased normal force and thus an improved friction effect.

[0036] According to a further development, the second friction surface can be formed on the iron core. This has the advantage that no separate friction lining is required.

[0037] Furthermore, it may be expedient if the coil is arranged on one side of the damper rod, wherein the first friction surface is formed on that side surface of the damper rod on which the coil is arranged and that the iron core is embedded in the coil in such a way that in the energized state of the coil

[0038] - the friction lining rests on the iron core and the damper rod rests on the friction lining, with the friction lining resting between the iron core and the damper rod or

[0039] - the damper rod rests against the iron core, whereby the contact force between the first friction surface and the second friction surface is higher when the coil is energized than when the coil is de-energized. This design results in a simple structure that can achieve high reliability.

[0040] Furthermore, it can be provided that the damper rod has a damper rod coating which serves to increase the coefficient of friction and / or to protect the damper rod from corrosion, in particular that the first friction surface is arranged on the damper rod coating, in particular that the damper rod coating is ferromagnetic. This has the advantage that this measure can achieve improved functionality. In particular, this measure can prevent the first friction surface from rusting onto the second friction surface, as a result of which good functional retention of the friction damper can be achieved over its service life. Furthermore, this measure can harden the surface, as a result of which wear can be reduced. A ferromagnetic coating can achieve an improved course of the magnetic field lines.

[0041] Furthermore, it can be provided that the iron core has an iron core coating which serves to increase the coefficient of friction and / or to protect the iron core from corrosion, in particular that the second friction surface is arranged on the iron core coating, in particular that the iron core coating is ferromagnetic. This has the advantage that this measure can achieve improved functionality. In particular, this measure can prevent rusting of the first friction surface on the second friction surface, as a result of which good functional retention of the friction damper can be achieved over its service life. Furthermore, this measure can harden the surface, as a result of which wear can be reduced. A ferromagnetic coating can achieve an improved course of the magnetic field lines.

[0042] According to a particular embodiment, it is possible for the damper rod to be elastically deformed into a first position when the coil is energized, and for the damper rod to be returned to an initial position when the coil is de-energized. In particular, in the initial position of the damper rod, the second friction surface and the first friction surface do not abut one another. This has the advantage that, when the coil is de-energized, the damper rod can be moved smoothly relative to the main damper part. Furthermore, this measure can prevent the first friction surface and the second friction surface from rusting against one another, even during extended periods of inactivity.

[0043] According to an advantageous development, it can be provided that a return spring is formed, by means of which the damper rod is pressed into an initial position when the coil is de-energized, and the damper rod is pressed into a first position against the spring force of the return spring when the coil is energized, in particular that the second friction surface and the first friction surface do not lie against one another in the initial position of the damper rod. This has the advantage that, when the coil is de-energized, the damper rod can be moved smoothly relative to the main damper part. Furthermore, this measure can ensure that the first friction surface and the second friction surface do not rust together, even after prolonged standstill.

[0044] In particular, it can be advantageous if the damper rod has a rectangular cross-section and is designed as a stamped part. This has the advantage that the damper rod can have a simple and robust structure and, moreover, is easy to manufacture.

[0045] In an alternative embodiment, it can be provided that the damper rod has a trapezoidal or triangular cross-section, with two side surfaces being arranged at an angle to each other.

[0046] Furthermore, it can be provided that an additional coil is arranged in the main damper part, spaced apart from the coil in the longitudinal direction of the rod. This has the advantage that the friction force can be increased. Furthermore, this measure can create redundancy. The structure of the additional coil can be designed mutatis mutandis to the coil already described.

[0047] Furthermore, it can be provided that the coil and the other coil can be energized independently of each other. This measure makes it possible to vary the strength of the friction force without necessarily changing the current strength.

[0048] Furthermore, the rod support can be formed in a rod support part, which is made as an injection-molded plastic part. This has the advantage that the damper rod can have a simple and robust design and, moreover, can be easily manufactured.

[0049] According to the invention, a laundry appliance, in particular a washing machine, tumble dryer, or washer-dryer combination, is provided. The laundry appliance comprises:

[0050] - a base frame,

[0051] - a drum tray, which is mounted in the base frame so that it can move relative to the base frame,

[0052] - a laundry drum which is rotatably mounted in the drum tub;

[0053] - a drive motor to drive the laundry drum;

[0054] - a friction damper which acts between the base frame and the drum holder.

[0055] The friction damper is designed according to one of the above specifications. In particular, two to four of the friction dampers can be installed in the washing machine.

[0056] The laundry appliance according to the invention offers the advantage that the friction damper according to the invention allows for increased smoothness of operation and thus reduced noise pollution. Furthermore, the laundry appliance can have an increased service life thanks to the friction damper according to the invention.

[0057] According to a further development, it is possible for the damper rod to be coupled to the drum pan, and the main damper part to be coupled to the base frame. This has the advantage of extending the service life of the friction damper, since the majority of the friction damper's components are not subject to vibration.

[0058] For a better understanding of the invention, it is explained in more detail using the following figures.

[0059] They show in a highly simplified, schematic representation:

[0060] Fig. 1 shows a first embodiment of a laundry appliance;

[0061] Fig. 2 is a perspective view of a first embodiment of a friction damper;

[0062] Fig. 3 is a perspective sectional view of the first embodiment of the friction damper along section line III-III of Fig. 2;

[0063] Fig. 4 is a sectional view of a second embodiment of the friction damper without friction lining;

[0064] Fig. 5 is a sectional view of a third embodiment of the friction damper with coating;

[0065] Fig. 6 is a sectional view of the second embodiment of the friction damper with a damper rod in a first position;

[0066] Fig. 7 is a sectional view of a fourth embodiment of the friction damper with two coils; Fig. 8 is a perspective sectional view of a fifth embodiment of the friction damper, with the cutting line being chosen similar to the illustration in Fig. 3;

[0067] Fig. 9 is a perspective sectional view of a sixth embodiment of the friction damper, the section being chosen similar to the view in Fig. 3;

[0068] Fig. 10 is a perspective sectional view of a seventh embodiment of the friction damper, the section being chosen similar to the view in Fig. 3;

[0069] Fig. 11 is a perspective view of an eighth embodiment of the friction damper;

[0070] Fig. 12 is a sectional view of the eighth embodiment of the friction damper, wherein the cutting direction is selected according to the section line XII-XII of Fig. 11.

[0071] By way of introduction, it should be noted that in the variously described embodiments, identical parts are provided with identical reference symbols or component designations. The disclosures contained throughout the description can be applied analogously to identical parts with identical reference symbols or component designations. Furthermore, the positional information chosen in the description, such as top, bottom, side, etc., refers to the directly described and illustrated figure, and these positional information must be applied analogously to the new position in the event of a change in position.

[0072] Fig. 1 shows a schematic representation of a laundry appliance 1 in a sectional view. As can be seen from Fig. 1, the laundry appliance 1 may include a base frame 2. The base frame 2 may serve as the outer structure of the laundry appliance 1 and may also be referred to as a frame or housing.

[0073] Furthermore, it can be provided that a drum tub 3 is formed in the laundry appliance 1. The drum tub 3 can be slidably or movably received in the base frame 2. For example, it can be provided that the drum tub 3 is slidably attached to the base frame 2 by means of spring elements 4. Furthermore, it can be provided that a laundry drum 5 is rotatably received in the drum tub 3. In particular, it can be provided that the laundry drum 5 is rotatably mounted about a drum axis 6. Furthermore, a drive motor 7 can be formed, which serves to drive the laundry drum 5 relative to the drum tub 3.

[0074] As further evident from Fig. 1, a friction damper 8 can be provided between the drum pan 3 and the base frame 2, which serves to dampen the movement of the drum pan 3. In particular, it can be provided that several of the spring elements 4 or several of the friction dampers 8 act between the drum pan 3 and the base frame 2.

[0075] In particular, it can be provided that a first connection point of the friction damper 8 is coupled to the drum tray 3 and that a second connection point of the friction damper 8 is coupled to the base frame 2.

[0076] Fig. 2 shows a perspective view of a first embodiment of the friction damper 8. The friction damper 8 can comprise a damper rod 9 and a damper main part 10. The damper rod 9 can be designed to be displaceable relative to the damper main part 10 in a rod longitudinal direction 11.

[0077] Furthermore, it can be provided that the damper rod 9 is coupled to the base frame 2 or the drum pan 3 by means of a rod connection 12. Furthermore, it can be provided that the damper main part 10 is coupled to the base frame 2 or the drum pan 3 by means of a main part connection 13.

[0078] The rod connection 12 can be pivotally coupled to the damper rod 9 about a first pivot axis 14.

[0079] Additionally, a first transverse pivot axis can be provided that is arranged at 90° to the first pivot axis 14. The first pivot axis 14 and the first transverse pivot axis can be designed in the form of a universal joint. In an alternative embodiment, the rod connection 12 can be provided with a ball head for connection to the damper rod 9.

[0080] In particular, it can be provided that the damper rod 9 has a rectangular cross-section and is formed by a flat iron or by a stamped part from a piece of sheet metal. The damper rod 9 can have a rod width 16 and a rod thickness 17. In particular, it can be provided that the rod width 16 corresponds to a multiple of the rod thickness 17.

[0081] Furthermore, it can be provided that the first pivot axis 14 extends parallel to the direction of extension of the rod thickness 17.

[0082] The main part connection 13 can be pivotally coupled to the damper main part 10 about a second pivot axis 15.

[0083] Additionally, a second transverse pivot axis can be provided, arranged at 90° to the second pivot axis 15. The second pivot axis 15 and the second transverse pivot axis can be designed in the form of a universal joint. In an alternative embodiment, the main part connection 13 can be provided with a ball head for connection to the damper main part 10.

[0084] The first pivot axis 14 and the second pivot axis 15 can be formed parallel to each other.

[0085] In particular, it can be provided that the rod connection 12 is coupled to the drum tray 3 and that the main part connection 13 is coupled to the base frame 2.

[0086] As can be seen particularly well from Fig. 2, it can be provided that the rod width 16 corresponds to a multiple of the rod thickness 17, wherein the first friction surface 18 is arranged on the side surface 21 extending in the rod width 16 and the coil 22 is arranged entirely next to the side surface 21.

[0087] Fig. 3 shows the first embodiment of the friction damper 8 in a perspective sectional view along the section line III-III of Fig. 2, wherein the same reference numerals or component designations are used for the same parts as in the previous Fig. 2. To avoid unnecessary repetition, reference is made to the detailed description in the previous Fig. 2.

[0088] As can be seen from Fig. 3, a first friction surface 18 can be formed on the damper rod 9. The first friction surface 18 can extend over a partial area of ​​the damper rod 9. Furthermore, it is also conceivable for the first friction surface 18 to extend over the entire damper rod 9.

[0089] Furthermore, it can be provided that a rod receptacle 19 for receiving the damper rod 9 is formed in the main damper part 10. In particular, it can be provided that the damper rod 9 is guided in the rod receptacle 19 so as to be displaceable in the rod longitudinal direction 11. The rod receptacle 19 can have approximately the geometric shape of the damper rod 9 or form a recess in the main damper part 10 with the geometry of the cross-section of the damper rod 9.

[0090] In particular, it can be provided that a second friction surface 20 is formed in the rod receptacle 19 for interaction with the first friction surface 18. As can be seen from the first embodiment, it can be provided that the first friction surface 18 is formed on a side surface 21 of the damper rod 9 and that the second friction surface 20 is formed in the rod receptacle 19 in such a way that the first friction surface

[0091] 18 and the second friction surface 20 can be brought into contact with one another.

[0092] Furthermore, it can be provided that in the damper main part 10 in the area of ​​the rod holder

[0093] 19, a coil 22 is formed. The coil 22 can be arranged on that side of the damper rod 9 on which the first friction surface 18 is formed. In particular, it can be provided that the coil 22 has a coil winding wound around a coil axis 23. The coil axis 23 can be formed at a right angle to the first friction surface 18 or to the second friction surface 20. Furthermore, it can be provided that an iron core 24 is formed, in which the coil 22 is embedded.

[0094] Furthermore, it can be provided that a friction lining 25 is formed, which is arranged between the iron core 24 and the damper rod 9. In particular, it can be provided that the second friction surface 20 is formed on the friction lining 25.

[0095] In particular, it can be provided that the rod holder 19 is formed in a rod receiving part 26. The rod receiving part 26 can be formed as an injection-molded part made of a plastic part. Furthermore, it can be provided that a recess 27 for receiving the coil 22 is formed in the rod receiving part 26. The recess 27 can open directly into the rod holder 19. In particular, it can be provided that the recess 27 is in the form of a cylindrical bushing 28 which is formed in the rod receiving part 26. The cylindrical bushing 28 can extend beyond the thickness of the rod receiving part 26. Furthermore, it can be provided that the rod receiving part 26 has one or more webs 29 which serve to reinforce the rod receiving part 26. The webs 29 can extend away from the rod holder 19. In particular, it can be provided that webs 29 adjoin the cylindrical bushing 28.

[0096] Furthermore, a cover 30 can be provided, by means of which the recess 27 is closed. In particular, the cover 30 can be attached to the cylinder bushing 28.

[0097] Fig. 4 shows a further and possibly independent second embodiment of the friction damper 8, wherein the same reference numerals or component designations are used for the same parts as in the preceding Figs. 1 to 3. To avoid unnecessary repetition, reference is made to the detailed description in the preceding Figs. 1 to 3. Fig. 4 shows the friction damper 8 in a longitudinal section, wherein, for the sake of clarity, only the area around the coil 22 is shown.

[0098] As can be seen from Fig. 4, the second friction surface 20 can be formed directly on the iron core 24. Thus, the friction lining 25 can be omitted. Both the iron core 24 and the damper rod 9 can be formed from a ferromagnetic iron material.

[0099] Fig. 5 shows a further and possibly independent third embodiment of the friction damper 8, wherein the same reference numerals or component designations are used for the same parts as in the preceding Figs. 1 to 4. To avoid unnecessary repetition, reference is made to the detailed description in the preceding Figs. 1 to 4.

[0100] As can be seen from Fig. 5, a damper rod coating 31 can be formed on the damper rod 9. In particular, the first friction surface 18 can be formed on the damper rod coating 31. The damper rod coating 31 can partially or completely surround the damper rod 9. Furthermore, an iron core coating 32 can be formed on the iron core 24. The second friction surface 18 can be arranged on the iron core coating 32.

[0101] In Fig. 6, the second embodiment of the friction damper 8 is shown in a position in which the damper rod 9 is in an initial position 34, wherein again the same reference numerals or component designations are used for the same parts as in the preceding Figs. 1 to 4. To avoid unnecessary repetition, reference is made to the detailed description in the preceding Figs. 1 to 4.

[0102] The function of the friction damper 8 is described below with reference to Figs. 4 and 6. In particular, it can be provided that in a position as shown in Fig. 6, the coil 22 is not energized and thus no magnetic field acts on the damper rod 9. The damper rod 9 can here be in an initial position 34. The first friction surface 18 and the second friction surface 20 can be arranged at a distance from one another. This makes it possible for the damper rod 9 and the main damper part 10 to be displaced relative to one another in the longitudinal direction 11 of the rod without a damping effect being achieved. The positioning of the damper rod 9 in the initial position 34 can be achieved by means of a spring element or by the spring stiffness of the damper rod 9 itself.

[0103] When the coil 22 is energized, a magnetic force of attraction from the iron core 24 can act on the damper rod 9, pulling the damper rod 9 from the starting position 34 into a first position 33, as shown in Fig. 4. In the first position 33, the first friction surface 18 can abut the second friction surface 20, generating a frictional force that impedes displacement of the main damper part 10 relative to the damper rod 9. This makes it possible to achieve the damping function. The magnetic field lines that occur here are shown schematically in Fig. 4.

[0104] The activation of the friction damper 8 can also take place in the further embodiments, as described with reference to Figures 4 and 6.

[0105] Fig. 7 shows a further embodiment of the friction damper 8, wherein the same reference numerals or component designations are used for the same parts as in the preceding Figures 1 to 6. To avoid unnecessary repetition, reference is made to the detailed description in the preceding Figures 1 to 6.

[0106] As can be seen from Fig. 7, it can be provided that a further coil 36 is formed in the rod's longitudinal direction 11, spaced from the coil 22. The further coil 36 can have a similar structure with an iron core, etc., as the coil 22. The coil 22 and the further coil 36 can be energized individually and independently of one another or together.

[0107] Fig. 8 shows a fifth embodiment of the friction damper 8 in a perspective sectional view, wherein the same reference numerals or component designations are used for the same parts as in the preceding Figures 1 to 6. To avoid unnecessary repetition, reference is made to the detailed description in the preceding Figures 1 to 6.

[0108] The operating principle of the friction damper 8 of the fifth embodiment is similar to that of the previously described embodiments. In the embodiment shown in Fig. 8, a plunger core 37 is formed, which can be arranged on the damper main part 10 so as to be displaceable relative to the iron core 24. In particular, it can be provided that the plunger core 37 has a plunger core guide 42, by means of which it can be guided in the iron core 24. Correspondingly, a damper rod recess 41 can be formed in the damper rod 9, through which the plunger core guide 42 can protrude. The plunger core 37 can thus be arranged on the side of the damper rod 9 opposite the coil 22.

[0109] Furthermore, it can be provided that a third friction surface 38 is formed on the damper rod 9 opposite the first friction surface 18. Furthermore, it can be provided that a fourth friction surface 39 is formed on a second friction lining 40. The second friction lining 40 can be arranged on the plunger core 37. To increase the friction effect, the damper rod 9 can be clamped between the friction lining 25 and the second friction lining 40. According to the embodiment shown in Fig. 8, the magnetic field lines 35 can run over the friction lining 25, the second friction lining 40, the iron core 24, the plunger core 37, and the plunger core guide 42 when the coil 22 is energized.

[0110] Fig. 9 shows a sixth embodiment of the friction damper 8 in a perspective sectional view, wherein again the same reference numerals or component designations are used for the same parts as in the preceding Figures 1 to 8. To avoid unnecessary repetition, reference is made to the detailed description in the preceding Figures 1 to 8.

[0111] In the embodiment according to Fig. 9, the iron core 24 can enclose the coil 22 together with the plunger core guide 42. In this case, it can be provided that the plunger core guide 42 has a gap 43 when the plunger core guide 42 is not energized, which gap is closed when the coil 22 is energized. The magnetic field lines 35 can thus run over the iron core 24 and the plunger core guide 42. When the coil 22 is energized, the effect of reluctance is utilized, whereby the gap 43 is reduced or closed, and the plunger core 37 is drawn toward the coil 22. This allows the damper rod 9 to be clamped between the friction lining 25 and the second friction lining 40. Since in such a design the magnetic field lines 35 do not run over the friction lining 25, the second friction lining 40 or the damper rod 9, it is not absolutely necessary for these components to be ferromagnetic.

[0112] Fig. 10 shows a seventh and possibly independent embodiment of the friction damper 8, wherein the same reference numerals or component designations are used for the same parts as in the preceding Figs. 1 to 9. To avoid unnecessary repetition, reference is made to the detailed description in the preceding Figs. 1 to 9.

[0113] As can be seen from Fig. 10, the damper rod 9 can be provided with a trapezoidal cross-section. The two lateral legs can be arranged at an acute angle to one another. In particular, it can be provided that the two lateral legs of the damper rod 9 are also designed as a first friction surface 18. Correspondingly, the two lateral legs in the rod holder 19 can be designed as a second friction surface 20. Providing the two lateral legs at an acute angle to one another has the advantage that a wedge effect can be used when the damper rod 9 is tightened in the direction of the coil 22. Thus, compared to a rectangular design of the damper rod 9, an increased friction effect can be achieved with the same coil force.

[0114] The effect described in Fig. 10 can also be used, mutatis mutandis, in an embodiment with a damper rod 9 with a triangular cross-section. A separate illustration or description of a damper rod 9 with a triangular cross-section is therefore omitted.

[0115] In all embodiments, it can be provided that the first friction surface 18 is arranged in a plane and that the coil 22 has a coil winding wound around the coil axis 23, wherein the coil axis 23 is arranged at a right angle to the first friction surface 18. In particular, it can be provided that the coil axis 23 intersects the first friction surface 18.

[0116] Figs. 11 and 12 show an eighth and possibly independent embodiment of the friction damper 8, wherein the same reference numerals or component designations are used for the same parts as in the preceding Figs. 1 to 10. To avoid unnecessary repetition, reference is made to the detailed description in the preceding Figs. 1 to 10.

[0117] As can be seen from Fig. 11, the damper main body 10 can be provided with a base 44 and a cover 45. The base 44 can be coupled to the cover 45 by means of fastening screws. The coil 22 can be arranged in the base 44. The damper rod 9 can be arranged between the base 44 and the cover 45.

[0118] In particular, it can be provided that an armature disk 46 is formed, which is arranged between the coil 22 and the damper rod 9. The armature disk 46 can be coupled to a counter disk 48 by means of a coupling rod 47. The counter disk 48 can be arranged on a side of the damper rod 9 opposite the armature disk 46. In particular, it can be provided that the coupling rod 47 is guided through a damper rod recess 41 of the damper rod 9.

[0119] Furthermore, it can be provided that a friction lining 25 is formed, which is arranged between the iron core 24 and the damper rod 9, wherein the second friction surface 20 is formed on the friction lining 25. In particular, it can be provided that the friction lining 25 is coupled to the damper main part 10, in particular to the base 44, by means of fastening means.

[0120] Furthermore, it can be provided that a third friction surface 38 is formed on the damper rod 9 opposite the first friction surface 18 and a fourth friction surface 39 is formed on a second friction lining 40, wherein the second friction lining 40 is arranged on the counter disc 48.

[0121] When current is applied to coil 22, a magnetic field can be generated, which is represented by magnetic field lines 35. The magnetic field can press the armature disk 46 and thus also the counter disk 48 and thus the second friction lining 40 against the damper rod 9. The damper rod 9 can then be pressed against the friction lining 25. As a result, the first friction surface 18 and the second friction surface 20, as well as the third friction surface 38 and the fourth friction surface 39, can abut one another, thus generating friction, by means of which the damper rod 9 can be braked in its movement in the rod's longitudinal direction 11.

[0122] Furthermore, it can be provided that a guide pin 49 is formed, which serves to guide the armature disk 46 together with the coupling rod 47 relative to the coil 22. In particular, it can be provided that the guide pin 49 protrudes into the armature disk 46 and that the guide pin 49 is guided in a guide recess in the iron core 24.

[0123] Furthermore, it can be provided that the counter disc 48 is fastened to the coupling rod 47 by means of fastening means. In particular, it can be provided that a thread is formed on the coupling rod and that the counter disc 48 is screwed to the coupling rod by means of nuts.

[0124] The exemplary embodiments show possible embodiments. It should be noted at this point that the invention is not limited to the specifically illustrated embodiments. Rather, various combinations of the individual embodiments are also possible. This variation possibility, based on the teaching of technical action based on the invention in question, lies within the skill of the person skilled in the art. The scope of protection is determined by the claims. However, the description and drawings must be used to interpret the claims. Individual features or combinations of features from the various exemplary embodiments shown and described may represent independent inventive solutions in themselves. The problem underlying the independent inventive solutions can be derived from the description.

[0125] All information on value ranges in this description is to be understood as including any and all sub-ranges thereof, e.g. the information 1 to 10 is to be understood as including all sub-ranges starting from the lower limit of 1 and the upper limit of 10, ie all sub-ranges begin with a lower limit of 1 or greater and end with an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1, or 5.5 to 10.

[0126] For the sake of clarity, it should finally be pointed out that, in order to better understand the structure, some elements have been shown out of scale and / or enlarged and / or reduced in size.

[0127] Reference symbol list

[0128] Laundry appliance 32 Iron core coating base frame 33 First layer drum tub 34 Starting position spring element 35 Magnetic field line laundry drum 36 Further coil drum axis 37 Immersion core drive motor 38 Third friction surface friction damper 39 Fourth friction surface damper rod 40 Second friction lining damper main part 41 Damper rod recess rod longitudinal direction 42 Immersion core guide rod connection 43 Air gap main part connection 44 Base first pivot axis 45 Cover second pivot axis 46 Armature disk

[0129] Rod width 47 Coupling rod Rod thickness 48 Counter plate first friction surface 49 Guide pin

[0130] S rod holder second friction surface side surface

[0131] Coil Coil axis Iron core Friction lining

[0132] S rod receiving part recess cylinder bushing web cover

[0133] Damper rod coating

Claims

Patent claims 1. Friction damper (8) comprising: - a damper rod (9) having a first friction surface (18), the damper rod (9) extending in a rod longitudinal direction (11); - a damper main part (10), the damper main part (10) comprising: + a rod holder (19) for receiving the damper rod (9), wherein a second friction surface (20) for interacting with the first friction surface (18) is arranged in the rod holder (19), wherein the damper rod (9) is received in the rod holder (19) so as to be displaceable in the rod longitudinal direction (11); + a coil (22) for generating a magnetic field, wherein the coil (22) is designed to change the contact pressure of the first friction surface (18) and the second friction surface (20) against one another, characterized in that the damper rod (9) has a polygonal cross-section, wherein the first friction surface (18) is formed on a side surface (21) of the damper rod (9).

2. Friction damper (8) according to claim 1, characterized in that the coil (22) has a coil axis (23), wherein the coil axis (23) is arranged at a right angle to the rod longitudinal direction (11), wherein the coil axis (23) is straight, in particular that an iron core (24) is formed which is embedded in the coil (22).

3. Friction damper (8) according to claim 1 or 2, characterized in that the coil (22) has a coil winding which is hollow-cylindrical in cross section.

4. Friction damper (8) according to one of claims 1 to 3, characterized in that the first friction surface (18) is arranged in a plane and that the coil (22) has a coil winding which is wound around the coil axis (23), wherein the coil axis (23) is arranged at a right angle to the first friction surface (18).

5. Friction damper (8) according to claim 2 or 4, characterized in that the coil axis (23) intersects the first friction surface (18).

6. Friction damper (8) according to one of claims 1 to 5, characterized in that the damper rod (9) has a rod width (16) and a rod thickness (17), wherein the rod width (16) corresponds to a multiple of the rod thickness (17), wherein the first friction surface (18) is arranged on the side surface (21) extending in the rod width (16) and the coil (22) is arranged entirely next to the side surface (21).

7. Friction damper (8) according to one of the preceding claims, characterized in that the damper rod (9) is formed from a ferromagnetic material and the coil (22) and the damper rod (9) are positioned relative to one another in such a way that when the coil (22) is energized, a magnetic flux of the coil (22) passes through the damper rod (9).

8. Friction damper (8) according to one of claims 2 to 7, characterized in that a friction lining (25) is arranged between the iron core (24) and the damper rod (9).

9. Friction damper (8) according to claim 8, characterized in that an armature disk (46) is formed, which is arranged between the coil (22) and the damper rod (9), wherein the armature disk (46) is coupled to a counter-disk (48) by means of a coupling rod (47), wherein the counter-disk (48) is arranged on a side of the damper rod (9) opposite the armature disk (46), wherein a friction lining (25) is formed, which is arranged between the iron core (24) and the damper rod (9), wherein the second friction surface (20) is formed on the friction lining (25), wherein when the armature disk (46) is attracted to the coil (22) by means of the magnetic field, the first friction surface (18) of the damper rod (9) is pressed against the second friction surface (20) by means of the counter-disk (48).

10. Friction damper (8) according to claim 9, characterized in that a third friction surface (38) is formed on the damper rod (9) opposite the first friction surface (18) and a fourth friction surface (39) is formed on a second friction lining (40), wherein the second friction lining (40) is arranged on the counter disc (48), wherein upon attraction of the armature disc (46) to the coil (22), the damper rod (9) by means of the Counter disc (48) is clamped between the friction lining (25) and the second friction lining (40).

11. Friction damper (8) according to claim 9 or 10, characterized in that the coupling rod (47) is guided through a damper rod recess (41) of the damper rod (9).

12. Friction damper (8) according to one of claims 2 to 7, characterized in that the second friction surface (20) is formed on the iron core (24).

13. Friction damper (8) according to one of claims 8 to 9, characterized in that the coil (22) is arranged on one side of the damper rod (9), wherein the first friction surface (18) is formed on that side surface (21) of the damper rod (9) on which the coil (22) is arranged and that the iron core (24) is embedded in the coil (22) in such a way that in the energized state of the coil (22) - the friction lining (25) rests on the iron core (24) and the damper rod (9) rests on the friction lining (25), the friction lining (25) resting between the iron core (24) and the damper rod (9) or - the damper rod (9) rests on the iron core (24), wherein in the energized state of the coil (22) the contact force of the first friction surface (18) and the second friction surface (20) on each other is higher than in the de-energized state of the coil (22).

14. Friction damper (8) according to one of the preceding claims, characterized in that the damper rod (9) has a damper rod coating (31) which serves to increase the coefficient of friction and / or to protect the damper rod (9) against corrosion, in particular that the first friction surface (18) is arranged on the damper rod coating (31), in particular that the damper rod coating (31) is ferromagnetic.

15. Friction damper (8) according to one of the preceding claims, characterized in that the iron core (24) has an iron core coating (32) which is used for Increasing the coefficient of friction and / or for corrosion protection of the iron core (24), in particular that the second friction surface (20) is arranged on the iron core coating (32), in particular that the iron core coating (32) is ferromagnetic.

16. Friction damper (8) according to one of the preceding claims, characterized in that the damper rod (9) is elastically deformed into a first position (33) in the energized state of the coil (22) and the damper rod (9) is returned to an initial position (34) in the de-energized state of the coil (22), in particular that in the initial position (34) of the damper rod (9) the second friction surface (20) and the first friction surface (18) do not abut one another.

17. Friction damper (8) according to one of the preceding claims, characterized in that a return spring is formed, by means of which the damper rod (9) is pressed into an initial position (34) in the de-energized state of the coil (22) and the damper rod (9) is pressed into a first position (33) against the spring force of the return spring in the energized state of the coil (22), in particular that in the initial position (34) of the damper rod (9) the second friction surface (20) and the first friction surface (18) do not lie against one another.

18. Friction damper (8) according to one of the preceding claims, characterized in that the damper rod (9) has a rectangular cross-section and is formed as a stamped part from a sheet metal.

19. Friction damper (8) according to one of the preceding claims, characterized in that a further coil (36) is arranged in the damper main part (10) in the rod longitudinal direction (11) at a distance from the coil (22).

20. Friction damper (8) according to one of the preceding claims, characterized in that the rod receptacle (19) is formed in a rod receptacle part (26), wherein the rod receptacle part (26) is formed as an injection-molded part made of a plastic, wherein the rod receptacle part (26) has a recess (27) for receiving the coil (22).

21. Laundry appliance (1), in particular washing machine, tumble dryer or washer-dryer combination, the laundry appliance (1) comprising: - a base frame (2), - a drum tray (3) which is movably mounted in the base frame (2) relative to the base frame (2), - a laundry drum (5) which is rotatably received in the drum tub (3); - a drive motor (7) for driving the laundry drum (5); - a friction damper (8) which acts between the base frame (2) and the drum tray (3), characterized in that the friction damper (8) is designed according to one of the preceding claims.

22. Laundry appliance (1) according to claim 21, characterized in that the damper rod (9) is coupled to the drum tub (3) and the damper main part (10) is coupled to the base frame (2).

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