DAMPER, IN PARTICULAR FRICTION DAMPER

Abstract

A damper, in particular for washing machines having a spin cycle, includes a housing having a central longitudinal axis and at least partially enclosing a housing inner space by housing walls, a tappet which can be displaced in the housing along the central longitudinal axis and is guided out of the housing, fastening members which are arranged at free ends of the housing and of the tappet, and at least one compensation member for compensating a play between the housing walls and the tappet.

Claims

1. A damper, comprising a. a housing having a central longitudinal axis and at least partially enclosing a housing inner space by housing walls, b. a tappet which can be displaced in the housing along the central longitudinal axis and is guided out of the housing, c. fastening members which are fastened to free ends of the housing and the tappet, comprising d. at least one compensation member for compensating a play between the housing walls and the tappet.

2. The damper according to claim 1, wherein the damper is intended for washing machines having a spin cycle.

3. The damper according to claim 1, wherein the at least one compensation member is integrally formed on the tappet.

4. The damper according to claim 1, wherein the at least one compensation member is arranged at the housing.

5. The damper according to claim 4, wherein the at least one compensation member is fastened to the housing.

6. The damper according to claim 4, wherein the at least one compensation member is integrally formed.

7. The damper according to claim 1, wherein the at least one compensation member has a compensation member length which extends along the central longitudinal axis.

8. The damper according to claim 1, comprising two compensation members.

9. The damper according to claim 8, wherein the two compensation members are oriented in opposite directions with respect to a center plane of the tappet.

10. The damper according to claim 1, wherein the at least one compensation member holds the tappet in the housing without play.

11. The damper according to claim 1, wherein the at least one compensation member is configured as a lamella, wherein the lamella at least one of extends at least in portions transversely to the central longitudinal axis and is oriented obliquely.

12. The damper according to claim 11, wherein the lamella is configured in a wave-like manner.

13. The damper according to claim 1, wherein at least one of the housing and the tappet is double-T-shaped in cross-section.

14. The damper according to claim 13, wherein at least one of the housing and the tappet is perpendicular to the central longitudinal axis.

15. The damper according to claim 1, wherein the tappet has an intermediate web defining a center plane.

16. The damper according to claim 15, wherein the center plane comprises the central longitudinal axis.

17. The damper according to claim 1, wherein the tappet has at least one friction lining recess.

18. The damper according to claim 17, wherein the at least one friction lining recess completely penetrates the tappet.

19. The damper according to claim 17, wherein the at least one friction lining recess has one of a rectangular and diamond-shaped form.

20. The damper according to claim 17, wherein the friction lining recess is bounded by end sides located at the axial ends and longitudinal sides connecting the latter.

21. The damper according to claim 20, wherein at least one end side is configured to be serrated.

22. The damper according to claim 1, comprising at least one friction lining.

23. The damper according to claim 22, wherein the at least one friction lining is arranged in the at least one friction lining recess and rests in a frictional manner against at least one housing wall.

24. The damper according to claim 22, wherein the shape of the friction lining is adapted to the shape of a friction lining recess.

25. The damper according to claim 22, wherein the friction lining is configured to be serrated on at least one end side.

26. The damper according to claim 1, wherein the housing has a housing body.

27. The damper according to claim 26, wherein the housing body is made in one piece.

28. The damper according to claim 1, wherein at least one friction insert is arranged on the inside of the housing.

29. The damper according to claim 28, wherein the friction insert forms the at least one compensation member.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0026] FIG. 1 shows a perspective exploded illustration of a damper according to a first embodiment including compensation members on the tappet as wave-shaped lamellae,

[0027] FIG. 2 shows a top view onto the damper according to FIG. 1 with the tappet partially inserted into the housing,

[0028] FIG. 3 shows a sectional illustration according to section line III-III in FIG. 2,

[0029] FIG. 4 shows an enlarged sectional representation according to section line IV-IV in FIG. 3,

[0030] FIGS. 5 to 7 shows illustrations, corresponding to FIGS. 2 to 4, of a damper according to a second embodiment, having lamellae that are oriented linearly and parallel to the central-longitudinal axis,

[0031] FIGS. 8 to 10 shows illustrations, corresponding to FIGS. 2 to 4, of a damper according to a third embodiment, having multiple transverse lamellae,

[0032] FIGS. 11 to 13 shows illustrations, corresponding to FIGS. 2 to 4, of a damper according to a fourth embodiment, having linear lamellae which are oriented transversely to the central longitudinal axis,

[0033] FIG. 14 shows a sectional view corresponding to FIG. 4 of a damper according to a fifth embodiment including surface-type spring members as compensation members on the housing.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] In the following, a first embodiment of the invention is described with reference to FIGS. 1 to 4. A damper 1 has a housing 2 with a central longitudinal axis 3, in which a tappet 4 is guided in a displaceable manner. The housing 2 is formed in one piece. It is also possible to provide the housing 2 composed of several parts, in particular two parts. The housing 2 has an outer, axial end 5 and an opposite end 6 that faces the tappet 4. In the region of the end 5, the housing 2 has a fastening member 7, in particular in the form of an eye, via which the housing 2 is fastened and articulated in the washing machine. The tappet 4 can be inserted into the housing 2 along an insertion direction 8 which runs parallel to the central longitudinal axis 3. At the outer end 9 of the tappet 4, which is opposite to the direction 8, the tappet 4 has a fastening member 10 in the form of an eye, via which the tappet 4 is articulated and fastened in a washing machine. The tappet 4 can be prevented from being pulled completely out of the housing 2 by extension limiting means which are not shown.

[0035] Starting behind the fastening member 10 in the direction 8, the tappet 4 has a double-T-shaped or H-shaped cross-section, which is formed by two side webs 11, 12, which run parallel to each other, and by an intermediate web 13 arranged between them, which connects the side webs 11, 12 to each other. The intermediate web 13 runs perpendicular to the side webs 11, 12. In the region of the end of the tappet 4 located in the direction 8, a friction lining recess 14 is provided in the intermediate web 13, which completely penetrates the intermediate web 13, i.e. is open to two sides - upward and downward. The recess 14 is bounded on all sides by the intermediate web 13, i.e. in the plane that is formed by the intermediate web 13. The recess 14 has a rectangular shape including parallel longitudinal sides 15 located along the direction 8 and parallel end sides 16 connecting the longitudinal sides 15. In the recess 14, a friction lining 17 is arranged, the shape of which in the simplest case corresponds essentially to that of the recess 14. The friction lining 17 is thus cuboidal, wherein its end sides 19 rest against the end sides 16 of the recess 14 and its longitudinal sides 18 rest against the longitudinal sides 15 of the recess 14. Otherwise, the friction lining 17 has two friction surfaces 20 that run parallel to each other and form the top and bottom of the cuboid. The friction lining 17 consists, for example, of a suitable foam material. The friction lining 17, which is itself preferably formed in one piece, is located directly on the edge of the recess 14 on the tappet 4, which is preferably formed in one piece.

[0036] The housing 2 encloses a housing inner space 21 whose cross-sectional shape corresponds to the outer contour of the tappet 4, i.e. the housing 2 also has a double-T cross-sectional shape. Two longitudinal channels 22 that extend along the central longitudinal axis 3 and correspond to the side webs 11, 12 are formed in the housing 2 and are connected to each other by an intermediate channel 23 that corresponds to the intermediate web 13. The longitudinal channels 22 are defined by longitudinal channel walls 24. The intermediate channel 23 is defined by two opposite intermediate channel walls 25 that run parallel to each other. Planar friction inserts 26 made of sheet metal are fastened to the intermediate channel walls 25. These friction inserts 26 are fixed in the region of transition to the fastening member 10 by L-shaped recesses 27, which are provided in corresponding longitudinal grooves in the intermediate channel wall 25. The friction inserts 26 extend over the full length of the housing inner space 21 and are each located between the intermediate channel walls 25 and the intermediate web 13 of the tappet 4. The housing 2 is advantageously made of plastic. The friction inserts 26 can, for example, be made of sheet steel.

[0037] The damper 1 is a friction damper.

[0038] Two compensation members 28 are arranged at the tappet 4, in particular at its intermediate web 13. The compensation members 28 are each designed as a wave-shaped lamella. Along the central longitudinal axis 3, the compensation members 28 have a compensation member length L.sub.AE which, according to the embodiment shown, corresponds to more than 50% of a free length L.sub.f of the tappet 4. The greater the length L.sub.AE, the sturdier the support of the tappet 4 in the housing 2. The free length L.sub.f is understood to mean the length portion of the intermediate web 13 of the central longitudinal axis 3, which length portion is axially bounded by the fastening member 10 on the one hand and the friction lining recess 14 on the other hand. Along the free length L.sub.f no, in particular no further, functional component of the damper 1 is arranged. A functional component is, for example, the friction lining recess 14.

[0039] The compensation members 28 are oriented transversely and in particular perpendicularly to a center plane 29 that is defined by the tappet 4, in particular the intermediate web 13. The center plane 29 contains the central longitudinal axis 3.

[0040] The compensation members 28 are in particular integrally molded onto the tappet 4, in particular by plastic injection molding. The compensation members 28 serve to support the tappet 4 in the housing 2, in particular against the intermediate channel walls 25 arranged in an opposite position or the friction inserts 26 attached thereto.

[0041] The compensation members 28 provide stable support for the tappet 4 against the opposite intermediate channel walls 25. Any play between the tappet 4 and the housing 2, in particular due to manufacturing tolerances, can be compensated for.

[0042] The compensation members 28 each rest with a contact surface 30 against the intermediate channel wall 25 or the friction insert 26. It is possible to implement the compensation members 28 using a separate, in particular soft, material, in particular a soft plastic, in particular in the region of the contact surfaces 30, in order to improve the compensation effect and in particular a resilient effect of the compensation members 28.

[0043] Due to the fact that the compensation members 28 are designed to be wave-shaped, there is a support width B.sub.S at which the compensation members 28 are supported against the opposite housing walls 25. The support width B.sub.S corresponds to a vertical projection of the contact surfaces 30 onto one of the housing walls 25.

[0044] The compensation members 28 allow a comparatively large support surface B.sub.S and thus a reduced surface pressure onto the contact surfaces 30. The wear of the compensation members 28 and the contact surfaces 30 is thus reduced.

[0045] By means of the compensation members 28, the tappet 4 is arranged in the housing without play. An undesired displacement of the tappet 4 in a direction perpendicular to the center plane 29 or a tilting of the tappet about a transverse axis 31 that is oriented perpendicular to the central longitudinal axis 3 and is located in the center plane 29 is thus prevented.

[0046] The compensation members 28 are arranged in the housing 2 with a preload which acts perpendicularly to the center plane 29. The preload results from the fact that the compensation members 28 have a free height H.sub.f in the region of the intermediate web 13, which free height H.sub.f is in particular greater than a vertical distance A.sub.s of the opposite intermediate channel walls 25 or of the friction inserts 26. This means that the compensation members 28 are compressed in a direction perpendicular to the center plane 29 when the tappet 4 is inserted into the housing 2.

[0047] In particular, the tappet 4 is arranged symmetrically with respect to the center plane 29 in the housing 2.

[0048] It is advantageous if the tappet 4 is axially guided with the two side webs 11, 12 parallel to the central longitudinal axis 3 in the housing 2, in particular in the longitudinal channels 22. This axial guidance is favored in particular by the fact that the side webs 11, 12 rest with guiding surfaces 32 that face each other on portions 33 of the friction inserts 26 that are bent over in an L-shape. This additionally reduces the noise generation.

[0049] In the following, the functional principle of the friction damper is described. The desired frictional force can be set, for example, by selecting the thickness D.sub.R of the friction lining 17. In particular, the friction lining 17 can have a thickness D.sub.R that is greater than the width Bz of the intermediate channel 23. The friction lining 17 is thus preloaded and rests against the friction surfaces 35 of the friction inserts 26. In the direction 8 and perpendicularly thereto in the plane formed by the intermediate web 13, the friction lining 17 is held by the end sides 16 and longitudinal sides 15. One friction lining 17 is in direct contact with the opposite friction surfaces 35. Thus, exactly only one friction lining 17 is required to act in a frictional manner on two opposite friction surfaces 35. Due to the shape of the recess 14 and the circumferential design of the friction lining 17, the damping characteristics of the damper 1 can be adjusted freely to a large extent.

[0050] If the tappet 4 is pushed in along the direction 8, the friction lining 17 is initially partially upset due to the static frictional forces between the friction surfaces 20 and the friction surfaces 35, whereby a slight freewheeling effect is achieved. This is followed by an increasing build-up of the sliding frictional force. The same applies to the subsequent withdrawal of the tappet 4 from the housing 2 against the direction 8. If the length L.sub.R of the friction lining 17 in the axial direction is smaller than the axial length L.sub.A of the recess 14, the friction lining 17 is more strongly upset when the tappet 3 is pushed in or pulled out. Thus, a more pronounced freewheeling effect occurs. If the length L.sub.R of the friction lining 17 is greater than the length L.sub.A of the recess 14, i.e. the friction lining 17 is axially preloaded in the recess 14, there is less or no freewheeling effect. The build-up of frictional force is therefore more abrupt. An advantage of the design is that its characteristics can be influenced, i.e. freewheeling or a soft build-up of frictional force, for example. Corresponding characteristics have a positive effect on the operating properties of the washing machine. For example, the floor forces are reduced and the acoustics are improved.

[0051] An additional improvement of the operating properties and thus a reduced noise development results from the compensation members 28, which compensate for the play between the housing walls 25 and the surfaces of the intermediate web 13 at the tappet 4. Rattling as a result of the tappet 4 moving in a direction that is perpendicular to the center plane 29 or tilting about the transverse axis 31 is prevented.

[0052] In the following, a second embodiment of the invention is described with reference to FIGS. 5 to 7. Identical parts are given the same reference signs as in the first embodiment, the description of which is hereby referred to. Structurally different but functionally similar parts are given the same reference signs with a trailing letter a.

[0053] In the case of the damper 1a, the compensation members 28a are each oriented parallel to the central longitudinal axis 3. The production of the damper 1a with linear lamella is simplified.

[0054] The compensation members 28a have a reduced support width B.sub.S. The integral contact surface 30 with which the tappet 4a rests against the housing 2 is reduced. This reduces the frictional influence of the tappet 4a compared to the frictional influence of the friction lining 17. The adjustment of the frictional force, in particular the frictional effect of the friction damper 1a, is thereby improved. The frictional effect can be influenced in a more targeted and immediate manner.

[0055] In the following, a third embodiment of the invention is described with reference to FIGS. 8 to 10. Identical parts are given the same reference signs as in the first two embodiments, the description of which is hereby referred to. Structurally different but functionally similar parts are given the same reference signs with a trailing letter b.

[0056] The damper 1b has a plurality of compensation members 28b that are spaced apart along the central longitudinal axis. The compensation members 28b also extend on both sides perpendicular to the center plane 29. The compensation members 28b are integrally formed on the tappet 4b, in particular in the intermediate web 13, and can be pivoted about a pivot axis 34. The pivot axis 34 is in particular parallel to the transverse axis 31.

[0057] According to the shown embodiment, four compensation members 28b are formed in series on the tappet 4b along the central longitudinal axis 3. Due to the separate design of the individual compensation members 28b, both the support width B.sub.S and the free height H.sub.f can be adapted and adjusted more flexibly.

[0058] It is understood that more or less than four compensation members 28b can be arranged along the central longitudinal axis 3. It is advantageous if the group of compensation members 28b extends over the advantageous length L.sub.AE, which is at least 50% of the free length L.sub.f.

[0059] In the following, a fourth embodiment of the invention is described with reference to FIGS. 11 to 13. Identical parts are given the same reference signs as in the previous embodiments, the description of which is hereby referred to. Structurally different but functionally similar parts are given the same reference signs with a trailing letter c.

[0060] The compensation members 28c are designed as linear lamellae, wherein the longitudinal axes of the compensation members 28c are oriented transversely at an angle of inclination n with respect to the central longitudinal axis 3. The compensation members 28c also extend on both sides of the tappet 4c perpendicular to the center plane 29.

[0061] The production, in particular the manufacturing, of the slanted lamella 28c is non-complex corresponding to the linear lamella of the second embodiment. The slanted lamella 28c has an increased support width B.sub.S, i.e. it is designed to be low-wear.

[0062] In the following, a fifth embodiment of the invention is described with reference to FIG. 14. Identical parts are given the same reference signs as in the previous embodiment examples, the description of which is hereby referred to. Structurally different but functionally similar parts are given the same reference signs with a trailing letter d.

[0063] In the case of the damper 1d, the compensation members 28d are arranged at the housing 2. The compensation members 28d are in particular formed as a special design of the friction inserts 26.

[0064] Unlike in the previous embodiments, the friction inserts 26 do not run parallel to the intermediate channel walls 25 of the housing 2 in the region facing the intermediate channel 23. The compensation members 28d are designed as bent sheet metal portions so that they rest against the tappet 4d to compensate for the play between the tappet 4d and the housing 2.

[0065] The design, in particular the manufacture, of the tappet 4d is simplified. In particular, the tappet 4d is designed without compensation members. Unwanted contamination, in particular in gaps of the tappet 4, for example by lint, is avoided. Gaps and/or slots in which lint can collect are not provided. The design of the damper 1d is robust and non-complex.

[0066] The compensation members 28d extend along the central longitudinal axis 3 along the compensation member length L.sub.AE.

[0067] According to an embodiment not shown, it is also possible to provide at least one compensation member at the housing 2 and at least one further compensation member at the tappet 4.