CZ9902406A3 - Friction damper, particularly for washing and the like machines - Google Patents

Abstract

The friction damper, especially for washing machines and the like, contains hollow a housing (1) and a rod (2) positioned coaxially and forming telescopic construction. The bar (2) is made with an outer one a diameter smaller than the inner diameter of the housing (1) and ve a friction element (3) is inserted into the gap. Element the friction damper (3) consists of at least two friction clamps (4, 5), touching the surface of the rod (2), axially these friction clamps (4, 5) are spaced axially apart that part of the rod (2) that is inserted into the housing (1).

Description

Friction damper, especially for washing machines and the like

Technical field

The present invention relates to a friction damper designed especially for washing machines and the like.

BACKGROUND OF THE INVENTION

As is known, the washing machine basket is usually mounted from above to support the load-bearing structure of the washing machine by means of a pair of springs, and from below it is fixed to said bearing of the load-bearing structure by a pair of shock absorbers.

Said shock absorbers are designed to attenuate the vibrations caused by the basket of the washing machine during its operation, the vibrations being caused by the rotating movement of the basket and the uneven distribution of the laundry, i.e. about the axis of said basket.

The vibration and vibration of the washing machine basket has a greater amplitude at the beginning and end of the washing cycle of the washing machine, i.e. at the greatest change in rotation speed.

Conventional shock absorbers used in conventional washing machines generally consist of a hollow housing and a rod that are coaxial to each other to form a withdrawable structure.

The damping effect is usually due to the compressed air held inside the device contained in said rod and housing, the compressed air being brought about by reducing the overall length of the housing and rod.

• · · ·

Among the commercially available damping machines for washing machines, friction dampers are also known which have a damping effect by the combined effect of the aforementioned compressed air held inside and a friction clamp located between the inner surface of the housing and the outer surface of the bar.

Typically, such a friction clamp is attached to the inner surface of the housing and the effective frictional effect is exerted between the friction clamp and the outer surface of the bar.

However, earlier friction dampers were disadvantageous due to the rapid wear of the bars as well as to the relatively high operating noise.

SUMMARY OF THE INVENTION

It is an object of the present invention to overcome the above problem by using a friction damper that has relatively less wear and thus a much longer service life compared to conventional friction dampers.

In addition to overcoming the drawbacks set forth in the above object of the invention, the main object of the present invention is to provide such a friction damper whose components would be subjected to low mechanical stresses and thereby avoid avoidable failures in said damper.

It is a further object of the present invention to provide such a silencer in which the operating noise is greatly reduced.

Another object of the present invention is to provide such a friction damper which is very reliable and safe in operation.

• · · ·

Another object of the present invention is to provide such a friction damper that can be manufactured at a competitive price.

According to particular aspects of the present invention, the above object and objects, as well as other objects to be explained below, these objects are achieved by a friction damper designed especially for washing machines and the like, wherein the friction damper with hollow housing and rod are stacked coaxially to each other and form an extendable structure and said rod is formed with an outer diameter smaller than the inner diameter of said housing and a friction damper element according to the invention is located in the gap between the inner diameter of the housing and the outer diameter of the rod. The shock absorber comprises at least two friction clamps contacting the surface of said rod, said axles being axially spaced apart on that portion of said rod which is inserted in said housing.

Overview of the drawings

Other characteristics and advantages of the friction damper of the present invention will become more apparent from the following detailed descriptions of several preferred, but not exclusive, embodiments of said damper, which are shown merely as explanatory but not limiting examples in the accompanying drawings, where:

Fig. 1 is an axial section showing a first embodiment of a damper according to the present invention;

Figure 2 is an enlarged view of part of Figure 1;

Fig. 3 and Fig. 4 are axial sections showing two other embodiments of the damper according to the present invention; and Fig. 5 is an axial section showing another embodiment of a damper according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

As shown in the accompanying drawings, the friction damper consists of a hollow bushing X and a rod 2, a portion of the rod 2 being inserted coaxially with respect to the housing X into its circular end.

The rod 2 is formed with an outer diameter smaller than the inner diameter of the housing X, and a friction damper element, which is indicated as a whole by reference number X, is located in the gap between the outer surface of the rod 2 and the inner surface of the housing X.

The friction damper element X consists of at least two friction clamps 4 and X, which are threaded on the outer surface of the rod 2 and axially positioned side by side on that part of the rod 2 which is inserted in the housing 1.

The friction clamps 4 and 5 are inserted into one or two retaining sleeves 18 and 18 and positioned therein on suitable shoulders 6 and 7 formed on the inner surfaces of said retaining sleeves 8 and 9.

Less common embodiments with a single retaining sleeve may also be provided with said shoulder 6 and 7 on their inner surface, provided that in this region between the two shoulder 6 shoulder bosses 6 and 7, the diameter is much larger than the outer diameter of the rod 2 and thus the collecting space for

-5 collecting by friction of waste material resulting from wear of friction clamps 4 and 5.

Another embodiment, which is shown in the accompanying figures, could also be made by placing the spacer 10 between the retaining sleeves 8 and 9 in which the friction clamps 4 and 5 are mounted on the shoulders 6 and 7 formed on the inner surfaces. said retaining sleeves 8 and 9.

Also, the spacer 10 will have a diameter much greater than the outer diameter of the rod 2.

Thus, in this area there would be a space for collecting the friction-separated material which separates due to wear of the friction clamps 4 and 5.

The friction-separated material produced by the wear of the friction clamps 4 and 5 will be collected in this region, thereby allowing proper sliding between the rod 2 and the friction clamps 4 and 5, while reducing wear of said rod 2.

The retaining sleeve or retaining sleeves 8 and 9 are axially secured within the sleeve X between two projections 11 and 12 formed around the inner surface of the sleeve X, the circular projections preferably being formed by bending a portion of said sleeve 1,

As shown in Figures 3 and 4, the end of the rod 2 is inserted in the housing X and this end is provided with an anti-fall protrusion which can be supported on the protrusion 11 or the protrusion securing the friction clamp in the retaining housing.

this protrusion is located deeper in the housing A · during operation

Said anti-falling protrusion can be easily realized, as clearly shown in Figure 3, by bending the end circular edge of the rod 2, which is inserted in the housing A, outwardly, the circular bending being indicated by reference number 15 in Figure 3.

As shown in Figure 4, said anti-falling protrusion may also be pressed by means of an end cap with a shoulder 16, which head is only inserted after the shoulder into the end of the rod 2.

As shown in Figure 5, a resilient damping member may be positioned between the end of the rod 2 inserted into the housing A and the end of the housing Α »opposite said end of the rod 2, this member being formed only by a helical spring 20.

Said coil spring 20 will operate to reduce the length of the withdrawable structure consisting of housing A and bar 2 when loading and unloading the laundry from the washing machine basket, and furthermore these damping springs usually connect the top of the washing machine basket to the washing machine supporting structure. .

The function of the friction damper according to the invention is explained in the preceding descriptions.

In particular, it should be clear that the basket vibrations and vibrations will be effectively dampened by sliding the bar 2 in the friction clamps 4 and 5.

Even the friction clamps 4 and 5 will greatly benefit from the accurate guidance of the rod 2 in the housing 1, under conditions of noiseless operation, which was one of the objects of the present invention.

In addition, if more than one friction clamp is contained, the friction surface will increase, thereby increasing the damping effect and, on the contrary, reducing the specific circumferential load of the friction clamps, resulting in an extended service life of the dampers.

At the end of the rod 2 which is not inserted into the housing 1 and at the end of the housing 1 into which the rod 2 is not inserted, the clamping heads 21 and 22 are fixed, these heads being of known construction and are therefore not further described here.

From the foregoing description and from the accompanying drawings, it should be understood that the present invention has achieved all the intended objects and objects.

In actual operation, it has been found that the friction damper is particularly stable and yet effectively damped, in virtually noiseless operation.

While the present invention has been described and illustrated in preferred embodiments, it is to be understood that several variations and modifications are possible in these embodiments, all of which will fall within the scope of the appended claims.

Claims (12)

PATENT CLAIMS A friction damper, in particular for washing machines and the like, having a hollow housing and a rod which are coaxial to one another and form a sliding structure of the friction damper, the rod being of an outside diameter smaller than the inside diameter of the housing and in the gap formed a friction damper element, characterized in that the friction damper element comprises at least two friction clamps contacting the surface of said rod and axially spaced by said friction clamps on that portion of said rod which is inserted in said said housing. A damper according to claim 1, characterized in that the friction clamps are seated on shoulders formed on the inner surface of the retaining sleeve, which is axially secured in said sleeve. Shock absorber according to the preceding claims, characterized in that the retaining sleeve defines a collecting space for collecting by friction of the waste material resulting from the wear of said friction clamps in the region between said shoulders on which the friction clamps are seated. 4. A damper according to claim 1, wherein each friction clamp is seated on a shoulder formed on the inner surface of the retaining sleeve axially secured in said housing, and between said retaining sleeves for receiving said friction clamps is placed spacer. Shock absorber according to one or more of the preceding claims, characterized in that the spacer is made with an inner diameter greater than the outer diameter of said rod so as to create a collecting space between said diameters and said friction clamps for friction collecting of waste material. resulting from the wear of said friction seals. Shock absorber according to one or more of the preceding claims, characterized in that the retaining sleeves are axially secured between two projections projecting from the inner surface of said sleeve. A damper according to one or more of the preceding claims, characterized in that said two protrusions are formed by permanent deformations on said housing. Shock absorber according to one or more of the preceding claims, characterized in that the end of the rod which is inserted in the housing is provided with a protrusion protrusion which can be supported on one of the two locking protrusions, the one which is smaller. . Shock absorber according to one or more of the preceding claims, characterized in that the anti-falling protrusion is formed by permanently bending said rod end. Shock absorber according to one or more of the preceding claims, characterized in that the anti-falling protrusion is realized by an end cap with a shoulder which is inserted into that end of said rod which is inserted in said housing. A damper according to one or more of the preceding claims, characterized in that a resilient damping member is disposed between the end of the rod sliding inside said housing and the opposite end of said housing. Shock absorber according to one or more of the preceding claims, characterized in that the resilient damping member is a helical spring which is positioned such that one end of the spring is supported on that end of said rod which is inserted in said housing and the other. the end rests on the opposite end of said housing.