CN104099752A - Damping force-variable vibration damper for washing machine - Google Patents

Abstract

The invention discloses a damping force-variable vibration damper for a washing machine. The vibration damper comprises a cylinder, a piston and at least one friction plate, wherein the friction plate closely clings to the inner wall of the cylinder, and contacts with the outer wall of the piston; the radius of one section of the piston is smaller than that of the other section of the piston. The vibration damper is applied to the high-amplitude working conditions of washing, rinsing, low-speed water extraction and the like of the washing machine as well as the low-amplitude working condition of high-speed water extraction; the vibration damper has a function of effectively suppressing the vibration of the washing machine, so that the vibration of an enclosure of the washing machine and the noise level of the whole washing machine are improved.

Description

A washing machine shock absorber with variable damping force

technical field

The invention relates to the technical field of home appliances, in particular to a shock absorber for a drum washing machine. the

Background technique

At present, due to the consideration of factors such as cost and manufacturing process, most washing machine manufacturers use shock absorbers with constant damping force. However, the entire working stroke of the drum washing machine includes both large-amplitude working conditions such as washing, rinsing, and low-speed dehydration, as well as small-amplitude working conditions such as high-speed dehydration. However, the larger damping force is easy to excite the larger vibration of the washing machine shell in the stage of small amplitude working conditions (such as high-speed dehydration), and the noise of the whole machine will also increase; If the device is not installed, the vibration of the large-amplitude working condition cannot be suppressed, and there is a risk of the whole machine being displaced. the

For example, the widely used shock absorber on the drum washing machine is a friction shock absorber, as shown in Figure 1 to Figure 3, the shock absorber includes a cylinder 1', a piston 2' and a friction plate 3', the circle One end of cylinder 1' is connected with the washing tub of the washing machine, and the other end of cylinder 1' is provided with an opening, and one end of piston 2' is inserted into cylinder 1' through the opening, and the other end of piston 2' is connected with the lower part of the washing machine casing. Connected, the friction plate 3' is close to the inner wall of the cylinder 1' and is in contact with the outer wall of the piston 2'. the

When the washing machine is working, the movement of the washing tub drives the cylinder 1' to move. For this reason, there is a relative movement between the friction plate 3' fixed on the inner wall of the cylinder 1' and the piston 2' with one end fixed on the shell of the washing machine. Principle, the piston 2' produces a damping force on the cylinder 1', the magnitude of the damping force is determined by the friction coefficient of the friction plate 3', the piston 2' and the pressure between them, and the direction is opposite to the relative movement direction of the two . The excessive vibration of the washing tub can be suppressed by using this damping force, but due to the principle of force interaction, the cylinder 1' will also produce a reaction force of equal magnitude and opposite direction to the piston 2', and the reaction force acts on the shell of the washing machine The lower part of the box makes the box shell vibrate accordingly. the

Therefore, it is necessary to design a new shock absorber, which is not only suitable for washing, rinsing, low-speed dehydration and other large-amplitude working conditions of the washing machine, but also suitable for high-speed dehydration such small-amplitude working conditions. Both can effectively suppress the vibration generated by the washing machine, thereby improving the vibration of the washing machine case and the noise level of the whole machine. the

Contents of the invention

The problem solved by the present invention is to provide a shock absorber, which is not only suitable for washing, rinsing, low-speed dehydration and other large-amplitude working conditions of the washing machine, but also suitable for high-speed dehydration such as small-amplitude working conditions. Both can effectively suppress the vibration generated by the washing machine, thereby improving the vibration of the washing machine case and the noise level of the whole machine. the

In order to solve the above problems, the present invention discloses a washing machine shock absorber with variable damping force. The shock absorber includes a cylinder, a piston and at least one friction plate. One end of the cylinder is connected to the washing tub of the washing machine connected, the other end of the cylinder is provided with an opening, one end of the piston is inserted into the cylinder through the opening, the other end of the piston is connected to the lower part of the washing machine casing, and the friction plate is close to the The inner wall of the cylinder is in contact with the outer wall of the piston, and the radius of one section of the piston is smaller than the radius of the remaining sections of the piston. the

Preferably, the smaller radius section of the piston is located in the middle of the piston. the

Preferably, the transition between the smaller radius section and the larger radius section of the piston is smooth through an oblique line or an arc. the

Preferably, the thickness of the friction plate is greater than the difference between the inner diameter of the cylinder and the smallest outer diameter of the piston. the

Preferably, the height of the friction plate is smaller than the height of the smaller radius section on the piston. the

Preferably, the cylinder is a plastic cylinder. the

Preferably, the piston is a metal piston. the

Preferably, the friction plate is arranged at the opening of the cylinder. the

Preferably, the friction plate is a high wear resistance friction plate. the

Compared with the prior art, the present invention has the following advantages: the shock absorber of the washing machine with variable damping force disclosed by the present invention includes a cylinder, a piston and at least one friction plate, one end of the cylinder is connected to the washing machine. The other end of the cylinder is provided with an opening, one end of the piston is inserted into the cylinder through the opening, the other end of the piston is connected to the lower part of the washing machine casing, and the friction plate is tightly Sticking to the inner wall of the cylinder and contacting the outer wall of the piston, the radius of one section of the piston is smaller than the radius of the remaining sections of the piston. The washing machine shock absorber with variable damping force disclosed by the present invention, by designing the radii of the pistons of the shock absorber to different sizes, when the washing machine is working, the pistons with different radius sizes are applied to different washing processes, which provides the washing machine with different radii during washing, Different stages such as rinsing and dehydration provide different damping forces to achieve the purpose of vibration reduction. the

Description of drawings

Fig. 1 is the overall structural representation of shock absorber in the prior art;

Fig. 2 is the longitudinal sectional view of shock absorber in the prior art;

Fig. 3 is the structural representation of shock absorber piston in the prior art;

Fig. 4 is the longitudinal sectional view of shock absorber in the preferred embodiment of the present invention;

Fig. 5 is the enlarged structural representation of the part between D-E in Fig. 4;

Fig. 6 is the structural representation of shock absorber piston in the preferred embodiment of the present invention;

Figure 7 is a longitudinal sectional view of the shock absorber in a preferred embodiment of the present invention when it is in a stretching stroke;

Figure 8 is a schematic diagram of the enlarged structure of the C-D part in Figure 7;

Fig. 9 is a longitudinal sectional view of the shock absorber in a compression stroke in a preferred embodiment of the present invention;

Figure 10 is a schematic diagram of the enlarged structure of the frame line part in Figure 9;

Among them: 1', cylinder; 2', piston; 3', friction plate; 1, cylinder; 2, piston; 3, friction plate. the

Detailed ways

The widely used shock absorber on drum washing machine is friction shock absorber at present, as shown in Figure 1 to Figure 3, this shock absorber includes a cylinder 1', a piston 2' and a friction plate 3', cylinder 1 One end of 'is connected to the washing tub of the washing machine, and the other end of the cylinder 1' is provided with an opening, and one end of the piston 2' is inserted into the cylinder 1' through the opening, and the other end of the piston 2' is connected to the lower part of the washing machine casing, The friction plate 3' is closely attached to the inner wall of the cylinder 1' and is in contact with the outer wall of the piston 2'. the

In this way, when the washing machine is running, the movement of the washing tub drives the cylinder 1' to move back and forth along the same axis as the cylinder 1' and the piston 2'. Since the friction plate 3' is fixed on the inner wall of the cylinder 1, the friction The sheet 3' continuously slides back and forth on the outer wall of the piston 2'. According to the principle of sliding friction force, the magnitude of friction force is determined by the coefficient of sliding friction and the normal pressure perpendicular to the sliding direction. The coefficient of sliding friction is related to the material and surface roughness of two rubbing objects. At the same time, since the diameters of the cylinder 1' and the piston 2' along the axial direction are constant values, the normal pressure on the friction plate 3' is also constant, and the shock absorber provided during the working process The amplitude of the damping force is also constant, that is, the amplitude of the damping force provided by the shock absorber during the entire operation of the washing machine, including the stages of low-speed washing, rinsing and high-speed dehydration, is the same. the

However, the entire working stroke of the drum washing machine includes both large-amplitude working conditions such as washing, rinsing, and low-speed dehydration, as well as small-amplitude working conditions such as high-speed dehydration. However, a large damping force is likely to excite a large vibration of the washing machine shell in the stage of small amplitude working conditions (such as high-speed dehydration), and the noise of the whole machine will also increase; and if a damping force with a small damping force is used If the vibrator is used, the vibration of the large-amplitude working condition cannot be suppressed, and there is a risk of the whole machine shifting. the

In view of the above-mentioned problems existing in the prior art, the present invention discloses a shock absorber for a washing machine with variable damping force. For small amplitude working conditions such as high-speed dehydration, the shock absorber can effectively suppress the vibration generated by the washing machine, thereby improving the vibration of the washing machine casing and the noise level of the whole machine. the

The technical solutions in the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. the

As shown in Figures 4 to 10, the present invention discloses a washing machine shock absorber with variable damping force, which includes a cylinder 1, a piston 2 and a friction plate 3, and one end of the cylinder 1 is connected to the washing tub of the washing machine The other end of the cylinder 1 is provided with an opening, one end of the piston 2 is inserted into the cylinder 1 through the opening of the cylinder 1, the other end of the piston 2 is connected with the lower part of the washing machine casing, and the friction plate 3 is closely attached to the cylinder 1 The inner wall is in contact with the outer wall of the piston 2, and the radius of one section of the piston 2 is smaller than the radius of the remaining sections of the piston 2. the

Different from the fixed value of the piston radius of the shock absorber in the prior art, the piston 2 of the shock absorber disclosed by the present invention has a variable radius structure, that is, the radius of a certain section of the piston 2 decreases. When the washing machine is in high-speed dehydration In this stage, the stroke of the friction plate 3 is within the smaller radius segment. Due to the increased gap between the outer wall of the piston 2 and the inner wall of the cylinder 1 in this segment, the positive pressure on the friction plate 3 is relative to that in the piston 2. The normal pressure on the other segments decreases; at the same time, since the sliding damping coefficient between the friction plate 3 and the piston 2 remains unchanged, the friction force amplitude in the smaller radius segment is reduced relative to other segments by the friction principle, thus The function of the shock absorber to provide a small damping force to suppress high-frequency and small vibrations is realized, so that the shock absorber is suitable for the high-speed dehydration stage of the washing machine. In the shock absorber disclosed by the present invention, except for a certain section of the piston 2 which has a smaller radius, the radii of the other sections are larger than this section. The stroke is within the larger radius segment (as shown in Figure 8, during the movement of the friction plate 3 from C to D position, or from D to C, the friction plate 3 in most areas is subjected to a relatively large positive pressure, Therefore, the shock absorber provides a larger damping force, and only when passing through the smaller radius interval, the amplitude of the damping force decreases, but because the smaller radius section occupies a smaller range than the C-D interval, the small damping force The stage is relatively short, most of which are stages of large damping force). At this time, the damping force of the shock absorber is relatively large in this part of the stroke, which is used to suppress the large vibration of the washing tub. the

Furthermore, when the shock absorber disclosed by the present invention is in the stretching stroke state in the state of large amplitude working condition, as shown in Figure 7, when the shock absorber disclosed in the present invention is in the state of large amplitude working condition The state during the compression stroke is shown in FIG. 9 . the

In a preferred embodiment of the invention, the smaller radius section of the piston 2 is located in the middle of the piston 2 . In specific operation, the position of the smaller radius section on the piston 2 on the entire piston 2 varies with the model of the washing machine, which can be calculated based on parameters such as the internal system weight of the washing machine of the applicable model, the stiffness of the hanging spring, the static balance position, and the magnitude of high-speed vibration out. the

Preferably, the transition between the smaller radius section and the larger radius section of the piston 2 is smoothly transitioned by an oblique line or an arc. In this way, the transition between the smaller radius section and the larger radius section of the piston 2 is smoother, so that the transition of the damping force of the shock absorber from large to small (or from small to large) is smoother and more stable. It is beneficial to the vibration and noise reduction of the washing machine. the

Preferably, the thickness of the friction plate 3 is greater than the difference between the inner diameter of the cylinder 1 and the smallest outer diameter of the piston 2 . In this way, when the shock absorber is assembled, the friction plate 3 is between the piston 2 and the cylinder 1, and is in a certain degree of compression. the

Preferably, the height of the friction plate 3 is smaller than the height of the smaller radius section on the piston 2 , so that the friction plate 3 can freely reciprocate and slide in the smaller radius section on the piston 2 . the

In addition, cylinder 1 is a plastic cylinder, and piston 2 is a metal piston. Of course, the cylinder 1 and the piston 2 can also be made of other suitable materials. the

Preferably, the friction plate 3 is arranged at the opening of the cylinder 1 . The friction plate 3 should be a friction plate with high wear resistance, so as to improve the overall service life of the shock absorber of the washing machine. the

The washing machine shock absorber with variable damping force disclosed by the present invention comprises a cylinder 1, a piston 2 and a friction plate 3, one end of the cylinder 1 is connected with the washing tub of the washing machine, and the other end of the cylinder 1 is provided with Opening, one end of the piston 2 is inserted into the cylinder 1 through the opening, the other end of the piston 2 is connected to the lower part of the washing machine casing, the friction plate 3 is close to the inner wall of the cylinder 1 and contacts the outer wall of the piston 2, and one part of the piston 2 The radius of is less than the radius of piston 2 remaining sections. The washing machine shock absorber with variable damping force disclosed by the present invention, by designing the radii of the piston 2 of the shock absorber to be of different sizes, when the washing machine is working, the piston 2 of different radius sizes is applied to different washing processes, which provides the washing machine with different radii. Different stages of washing, rinsing and dehydration provide different damping forces to achieve the purpose of vibration reduction. the

The washing machine shock absorber with variable damping force disclosed by the present invention does not add any parts to the existing washing machine shock absorber, and has simple structure, high reliability and low cost. the

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. the

Claims (9)

1. A washing machine shock absorber with variable damping force, characterized in that: the shock absorber includes a cylinder, a piston and at least one friction plate, and one end of the cylinder is connected with the washing bucket of the washing machine, so The other end of the cylinder is provided with an opening, one end of the piston is inserted into the cylinder through the opening, the other end of the piston is connected with the lower part of the washing machine casing, and the friction plate is tightly attached to the cylinder. The inner wall of the cylinder is in contact with the outer wall of the piston, and the radius of one section of the piston is smaller than the radius of the remaining sections of the piston. 2. The washing machine shock absorber with variable damping force according to claim 1, characterized in that: the smaller radius section of the piston is located in the middle of the piston. 3. The washing machine shock absorber with variable damping force according to claim 1 or 2, characterized in that: the smaller radius section of the piston and the larger radius section are smoothly transitioned through oblique lines or arcs. 4. The washing machine shock absorber with variable damping force according to claim 1, characterized in that: the thickness of the friction plate is greater than the difference between the inner diameter of the cylinder and the smallest outer diameter of the piston. 5. The washing machine shock absorber with variable damping force according to claim 1, characterized in that: the height of the friction plate is smaller than the height of the smaller radius section on the piston. 6. The shock absorber of a washing machine with variable damping force according to claim 1, wherein the cylinder is a plastic cylinder. 7. The shock absorber for a washing machine with variable damping force according to claim 1, wherein the piston is a metal piston. 8. The shock absorber of a washing machine with variable damping force according to claim 1, wherein the friction plate is arranged at the opening of the cylinder. 9. The shock absorber for a washing machine with variable damping force according to claim 1 or 8, characterized in that: the friction plate is a high wear resistance friction plate.