CN111284273A

CN111284273A - Damping mute wheel and movable equipment

Info

Publication number: CN111284273A
Application number: CN202010167836.6A
Authority: CN
Inventors: 王伯睿; 郑仙华; 倪维
Original assignee: Whale Computing Technology Group Co Ltd; Hangzhou Jingsuan Robert Technology Co Ltd
Current assignee: Whale Computing Technology Group Co Ltd; Hangzhou Jingsuan Robert Technology Co Ltd
Priority date: 2020-03-11
Filing date: 2020-03-11
Publication date: 2020-06-16

Abstract

The invention provides a damping mute wheel and a movable device, wherein the damping mute wheel comprises: a hub, the hub being annular; the wheel rim is fixedly connected to the radial outer side of the hub, the wheel rim comprises an outer layer, a plurality of scroll strips and a transition layer, the scroll strips are located on the radial inner side of the outer layer, the transition layer is located on the radial inner side of the scroll strips, the transition layer is connected with the hub, the scroll strips are uniformly arranged at intervals along the circumferential direction of the damping silent wheel, the rims are hollowed at intervals between the scroll strips, and the scroll strips are integrally bent to form a C-shaped structure; and the reinforcing member is annular, the reinforcing member is connected to the outer layer, and the elastic modulus of a material forming the reinforcing member is greater than that of a material forming the rim. By adopting the technical scheme, the vibration and the noise of the tire can be reduced, and the movable equipment can be kept quiet when moving.

Description

Damping mute wheel and movable equipment

Technical Field

The invention belongs to the field of tires, and particularly relates to a damping mute wheel and a movable device.

Background

The movement of movable equipment, such as luggage, over rough or uneven road surfaces can produce vibration and noise. In order to avoid the vibration and noise, solid rubber tires, foam tires, inflatable tires and the like are often adopted as tires in the prior art to bear movable equipment, so that certain vibration and noise reduction effects are achieved. But moving on uneven roads, there is still a strong noise. In order to further reduce vibration and noise, the prior art also adopts the following technical schemes:

(1) a damping spring is arranged between the tire and the movable equipment, and the spring has a certain damping effect. Although the mode of adopting spring damping can alleviate vibration and noise reduction to a certain extent, the damping of spring has the directionality, can only reduce unidirectional vibration impact. In addition, the mechanical structure of the spring increases the weight and generates noise when moving.

(2) The flexible tire tread has a certain vibration isolation effect, so that noise is reduced. However, due to the limited amount of deformation of the compliant tread, significant vibration and noise still occur on a road surface having significant roughness.

Disclosure of Invention

The invention aims to provide a damping mute wheel and a movable device, which can reduce vibration and noise during moving when the damping mute wheel is arranged on the movable device.

The invention provides a damping mute wheel, which comprises:

a hub, the hub being annular; and

the wheel rim is fixedly connected to the radial outer side of the hub, the wheel rim comprises an outer layer, a plurality of scroll strips and a transition layer, the scroll strips are located on the radial inner side of the outer layer, the transition layer is located on the radial inner side of the scroll strips, the transition layer is connected with the hub, the scroll strips are uniformly arranged at intervals along the circumferential direction of the damping silent wheel, the rims are hollowed at intervals between the scroll strips, and the scroll strips are integrally bent to form a C-shaped structure; and

the reinforcing member is annular and is connected to the outer layer, and the elastic modulus of a material forming the reinforcing member is larger than that of a material forming the rim.

Preferably, the modulus of elasticity of the material forming the reinforcement is greater than 500 Mpa.

Preferably, the reinforcement is embedded within the outer layer.

Preferably, the reinforcement is made of plastic, and the reinforcement is connected to the outer layer using a two-shot molding process or a two-shot molding process.

Preferably, the reinforcing member is made of metal, and the metal is attached to the outer layer by applying an adhesive to a surface of the reinforcing member.

Preferably, the circumferential dimensions of the two end portions of the banner in the radial direction of the damped mute wheel are larger than the circumferential dimension of the middle portion of the banner.

Preferably, the vibration-damping mute wheel further comprises a tread connected to the radially outer side of the outer layer, the material of the tread having a modulus of elasticity smaller than that of the material of the rim.

Preferably, when the vibration-damping mute wheel bears a rated static load, the ratio of the displacement amount of the shaft center of the vibration-damping mute wheel to the radius of the vibration-damping mute wheel is 0.03 to 0.20.

Preferably, a baffle is connected to the rim and/or the hub, and the hollow formed by the interval between the banners is covered by the baffle.

The invention also provides a mobile device, which comprises the damping and silencing wheel in any one of the technical schemes, wherein the rated static load of the damping and silencing wheel is less than 200 kg.

By adopting the technical scheme, the vibration and the noise of the tire can be reduced, and the movable equipment can be kept quiet when moving.

Drawings

Fig. 1 shows a schematic structural view of a shock-absorbing silent wheel according to a first embodiment of the present invention.

Fig. 2 shows an exploded view of a shock-absorbing mute wheel according to a first embodiment of the present invention.

Fig. 3 shows a schematic view of a damped silent wheel according to a first embodiment of the present invention, viewed in its axial direction.

Fig. 4 shows a partial enlarged view of fig. 3.

Fig. 5 shows a schematic view of a damped silent wheel according to a first embodiment of the present invention, viewed in its radial direction.

Fig. 6-8 show the noise data for test one.

Fig. 9 shows an exploded view of a damped silent wheel according to a second embodiment of the present invention.

Fig. 10 to 12 show the noise data of test two.

Fig. 13 shows a partial cross-sectional view of an outer layer of a shock-absorbing mute wheel according to a third embodiment of the invention.

Fig. 14-16 show noise data for test four.

Fig. 17 shows a schematic structural view of a shock-absorbing mute wheel according to a fourth embodiment of the present invention.

Fig. 18 shows an exploded view of a shock-absorbing mute wheel according to a fourth embodiment of the present invention.

Fig. 19-21 show the noise data for test five.

Description of the reference numerals

1 rim 11 outer layer 12 spoke 13 transition layer 14 reinforcing member 15 baffle 16 recess

2 wheel hub

3 Tread

I inside O outside S axis

R is radial A to axial C.

Detailed Description

To more clearly illustrate the above objects, features and advantages of the present invention, a detailed description of the embodiments of the present invention is provided in this section in conjunction with the accompanying drawings. As the present invention may be embodied in several forms other than the embodiments described in this section, those skilled in the art should appreciate that they may readily use the present invention as a basis for modifying or modifying other embodiments of the present invention without departing from the spirit or scope of the present invention. The protection scope of the present invention shall be subject to the claims.

In the following description, if not otherwise specified, radial direction R refers to the radial direction of the damped silent wheel, axial direction a refers to the axial direction of the damped silent wheel, and circumferential direction C refers to the circumferential direction of the damped silent wheel.

First embodiment

As shown in fig. 1 to 8, the present invention provides a vibration-damping silent wheel (hereinafter, sometimes referred to as a tire), the tire includes a rim 1 and a hub 2, the rim 1 and the hub 2 are annular, the rim 1 and the hub 2 are fixed together, the rim 1 is located at the radial outer side of the hub 2, for example, the rim 1 and the hub 2 can be connected together by clamping, bonding, two-shot molding or two-shot molding.

The invention also provides the movable equipment, wherein one or more damping mute wheels are arranged at the bottom of the movable equipment, and the damping mute wheels are arranged on the movable equipment in a mode that the wheel hub 2 is arranged on the shaft. The damping mute wheel can ensure that the vibration and the noise generated when the movable equipment moves on the ground are smaller. The weight of the mobile device is light, for example the mobile device can be a luggage, a mobile table, a mobile cabinet, etc., and the rated load of the single shock-absorbing mute wheel does not exceed 200 kg.

The rim 1 comprises an outer layer 11, a banner 12 and a transition layer 13, the outer layer 11 is located at the outermost layer of the rim 1 and can be used for contacting with the ground, the outer layer 11 and the transition layer 13 are annular, the banner 12 is located at the radial inner side of the outer layer 11, the transition layer 13 is located at the radial inner side of the banner 12, and the rim 1 is connected with the hub 2 through the transition layer 13.

As shown in fig. 5, the outer peripheral surface of the outer layer 11 is arc-shaped, the axially middle portion of the outer peripheral surface of the outer layer 11 protrudes radially outward beyond the axially both side portions, the contact surface of the outer layer 11 with the ground surface is small, and friction with the ground surface can be reduced. And the curved surface helps to achieve steering.

As shown in fig. 3, a plurality of spokes 12 are arranged at regular intervals in the circumferential direction C, and the rim 1 is hollowed out at the intervals between the spokes 12. The web 12 is made of an elastic material, such as cast polyurethane, thermoplastic elastomer or vulcanized rubber, which is capable of deforming to some extent when the web 12 is subjected to pressure. When the damping mute wheel is observed along the axial direction A, the whole scroll 12 is bent to be in a C-shaped structure, the bent shape enables the scroll 12 to have larger elasticity, and the scroll 12 is easier to deform when the damping mute wheel bears pressure.

The hub 2 is fixed to the shaft structure of the moving device or tool. The hub 2 is made of metal (including alloy) or plastic material, and if the elastic modulus of the hub 2 is too low, the elastic deformation of the hub 2 is obvious, and the service life is influenced. The hub 2 may be formed using an injection molding process, a casting process, or a 3D printing technique.

The outer layer 11 and the transition layer 13 are made of an elastic material, such as cast polyurethane, thermoplastic elastomer or vulcanized rubber.

The outer layer 11, the banner 12 and the transition layer 13 may be integrally formed from the same material, for example by injection moulding, casting or moulding to form the rim 1. The hub 2 can be connected with the rim 1 by bonding, secondary injection molding, double-color injection molding or clamping and nesting.

As shown in fig. 3, when the damper mute wheel is viewed in the axial direction a, the side where the banner 12 bends to form a depression is referred to as an inner side I of the banner 12, and the side where the banner 12 bends to form a projection is referred to as an outer side O of the banner 12. Both ends of the web 12 in the tire radial direction R are connected to the outer layer 11 and the transition layer 13, respectively, and the cross-sectional area of both end portions of the web 12 in the tire radial direction R is larger than the cross-sectional area of the middle portion of the web 12. Specifically, the circumferential dimensions of both end portions of the banner 12 in the radial direction R are larger than the circumferential dimension of the middle portion of the banner 12.

In the present embodiment, the axial dimensions of the portions of the banner 12 in the radial direction R are the same, and the axial dimensions of the banner 12 are the same as those of the outer layer 11 and the transition layer 13. Of course, in other possible embodiments, the axial dimensions of the portions of the web 12 in the radial direction R may also be different, and the axial dimensions of the web 12 may also be different from the axial dimensions of the outer layer 11 and the transition layer 13, for example the axial dimension of the web 12 is smaller than the axial dimension of the outer layer 11 and/or the axial dimension of the transition layer 13.

It is understood that stress concentration tends to occur at both end portions of the banner 12 in the radial direction R. If the cross-sectional area of the banner 12 is the same everywhere in the radial direction R, the stress of the inner part of the banner 12 at both ends in the radial direction R is significantly larger than the stress of the outer part of the banner 12. The size of the banner 12 is increased at a portion where stress concentration is likely to occur, so that the life span of the vibration damping and noise damping wheel can be increased.

As shown in fig. 4, the outer side of the banner 12 is formed by one or more arcs of a circle. The inner side surface of the scroll 12 is formed by connecting a plurality of sections of tangent arcs, and seven points a, b, c, d, e, f and g are sequentially arranged from the radial outer side to the radial inner side. a is located at the boundary of the banner 12 and the outer layer 11, g is located at the boundary of the banner 12 and the transition layer 13, the remaining points are located between a and g, and d is located at the middle position between a and g.

When the damping mute wheel is observed along the axial direction A, an arc line between two points ab is called an arc ab, an arc line between two points bc is called an arc bc, an arc line between two points cd is called an arc cd, an arc line between two points de is called an arc de, an arc line between two points ef is called an arc ef, and an arc line between two points fg is called an arc fg. The arcs ab and fg are arcs respectively convex toward the inner side I of the banner 12, and the arcs bc, cd, de, and ef are arcs respectively convex toward the outer side C of the banner 12.

The inner side of the banner 12 is formed by the plurality of tangent arcs, and the cross-sectional area corresponding to each position of the banner 12 is different from the size along the circumferential direction C. The cross-sectional area of the end of the banner 12 close to the axis S of the tire is smaller than the cross-sectional area of the end of the banner 12 away from the axis S of the tire, and the circumferential dimension of the end of the banner 12 close to the axis S of the tire is smaller than the circumferential dimension of the end of the banner 12 away from the axis S of the tire.

Specifically, with the axis S of the tire as the center of a circle, the lengths from a, b, C, d, e, f, g to the axis S are respectively used as radii, the arc lengths of the positions where the corresponding points a, b, C, d, e, f, g are located are the dimensions in the circumferential direction C corresponding to each position of the banner 12, and the circumferential dimensions of each position have the following relationship: a > g > b, f, d > c, e. By forming the spokes 12 in this manner, the cross-sectional area of the portion where stress is concentrated is large, which can improve the service life of the tire, and the cross-sectional area of the portion where stress is concentrated is small, which can also make the tire light in weight.

Further, the line connecting the two end points of the arc on the inner side I and/or the line connecting the two end points of the curve on the outer side O (which may be simply referred to as "line connecting both end portions of the banner 12 in the radial direction R") does not pass through the axis S of the tire as viewed in the axial direction a, and is deviated to the side of the inner side I of the banner 12 with respect to the axis S, as shown in fig. 4, for example, the line connecting the a and g is deviated to the side of the inner side I of the banner 12.

It will be appreciated that the curvature of the web 12 as a whole may be relatively small, in which case the deformation of the web 12 may be controlled and determined by connecting the ends of the web 12 in the radial direction R without passing through the axis S of the tire when the tire is under load. Otherwise, the banner 12 may sometimes bend toward the inner side I of the banner 12 and sometimes bend toward the outer side O of the banner 12, affecting the displacement amount of the axis S of the tire when the tire is subjected to a load.

When the tire is subjected to a rated static load, the tire deforms to change the position of the axis S of the tire, and the ratio of the displacement of the axis S of the tire to the radius of the tire may be 0.03 to 0.20. The ratio of the displacement of the axis S to the radius of the tyre can be varied by the configuration, number and choice of material of the spokes 12, the nominal static load being the design load of the damped silent wheel, normally less than 200 kg.

The rim 1 can be made of an elastic material having a stress (modulus of elasticity) of less than or equal to 100Mpa at 10% elongation, and if the modulus of elasticity of the rim 1 is too high, the fatigue life is reduced, affecting the service life of the tire.

Preferably, the number of the banners 12 is 12 to 40. If the number of the banners 12 is less than 12, the uniformity of the banners 12 with respect to the load support is significantly reduced, and periodic vibration may be generated. Influence silence nature, travelling comfort, the stress concentration phenomenon of scroll is also more obvious simultaneously, influences the life of shock attenuation silence wheel. If the number of the spokes 12 is more than 40, although the life of the damper mute wheel can be improved, it may result in an excessively small circumferential dimension of the individual spokes 12, resulting in an increased difficulty in manufacturing the spokes 12 and an increased cost of the die.

Test one

The influence of the banner 12 on the damping and silencing effect is verified through testing.

Tires A, B, C were made with 0, 10, 24 swaths. A number of spokes of 0 indicates that the rim is solid and annular, without any hollowed-out portions between the spokes and the spoke. The tires A, B and C are respectively assembled in the same luggage case, and are dragged on different road surfaces, and the vibration and the generated noise of the luggage case handle are tested.

TABLE 1

As can be seen from table 1, the tire having the banner 12 has a significant vibration and noise reduction effect. However, if the number of the scroll bars is too small, the luggage case may be towed with periodic vibration, which is not preferable.

Table 1 shows subjective feelings of the testers, fig. 6 to 8 show specific noise data of the above tests, fig. 6 is data of the test on a smooth and flat road surface, fig. 7 is data of the test on an asphalt road surface, and fig. 8 is data of the test on a brick floor surface.

It will be appreciated that the human ear is sensitive to sound at different frequencies to a varying degree, and is most sensitive to sound at frequencies of 1000 hz to 3000 hz, so tests have focused on the number of decibels of noise in this range. Decibels are units of measure for measuring the ratio of the numbers of two same units, and represent a logarithmic relationship, so that even if the decibels differ by only a few decibels, the difference between the power intensities of the sounds is very large, and the difference between the audiences of the human ears is very obvious.

In fig. 6 to 8, the horizontal axis represents frequency (in Hz), and the vertical axis represents the magnitude of noise at the corresponding frequency, in dBSPL (i.e., sound pressure as decibels of a measurement). As can be seen from fig. 6 to 8, the noise of the tire C is significantly smaller than that of the tire B, which is smaller than that of the tire a.

Second embodiment

The shock-absorbing mute wheel of the second embodiment is similar to the overall structure of the shock-absorbing mute wheel of the first embodiment, and the same reference numerals are used for the same or similar structures in the second embodiment as those of the first embodiment, and detailed description is not given.

As shown in fig. 9, the vibration-damping silent wheel includes a rim 1, a hub 2, and a tread 3, and the tread 3 is attached to the radially outer side of an outer layer 11. The tread 3, which is the outermost layer of the vibration-damping silent wheel, is the portion of the vibration-damping silent wheel that contacts the ground. The tread 3 may be formed by injection molding, casting or molding processes. The tread 3 is made of an elastomeric material, which may be a cast polyurethane, a thermoplastic elastomer or a vulcanized rubber. The tread 3 may be an elastic material having a stress (modulus of elasticity) at 10% elongation of less than or equal to 60Mpa, for example a material having a modulus of elasticity of 4.7Mpa measured according to the ISO 37 standard. The higher the stress, the higher the modulus of elasticity of the tread 3, the harder the tread 3, and the lower the stress, the lower the modulus of elasticity of the tread 3, the softer the tread 3.

It is understood that if the modulus of elasticity of the material of the tread 3 is too high, the vibration damping and noise reduction performance of the tread 3 is not good. The elastic modulus of the material of the tread 3 is smaller than that of the material of the rim 1, so that the tire has better vibration and noise reduction performance.

The outer peripheral surface of the tread 3 is arc-shaped, and the middle portion in the axial direction a of the outer peripheral surface of the tread 3 protrudes radially outward beyond the two side portions in the axial direction a of the tread 3, so that the contact surface between the tread 3 and the ground is reduced, and the friction between the tread 3 and the ground is reduced. And the curved tread helps to achieve steering.

Test two

The influence of the modulus of elasticity of the tread 3 on the damping silencing effect was verified by the second test.

The tread A and the tread B were each made using polyurethane castable A, B, where the modulus of elasticity for tread A made from castable A was 0.6MPa and for tread B made from castable B was 4.7 MPa.

Specifically, the casting material A is preheated and defoamed for 2 hours at 80 ℃, mixed with a curing agent for 1min (minute), then poured into a mold, placed in a 110 ℃ oven for curing for 30min, demoulded, and then placed in the 110 ℃ oven for curing for 16 hours (hour) to obtain the rim 1. The tread A and the tread B are obtained by respectively adopting the castable A and the castable B through the process. The rim 1 is connected to the hub 2, and the tread a and the tread B are connected to the rim 1 to obtain the tire a and the tire B, respectively. The two tires are of the same size, specifically 13mm in axial dimension and 52mm in diameter. Tires a and B were mounted on the same trunk, respectively, and the load of each tire was 4kg, and the tires were towed on different road surfaces, and the vibration of the handle and the generated noise were tested.

TABLE 2

As can be seen from table 2, the effect of the modulus of elasticity of the tread 3 on the vibration damping effect is insignificant. However, the modulus of elasticity of the tread has an influence on noise, and particularly, on a smooth flat road surface and an asphalt road surface, the tire a having a smaller modulus of elasticity of the tread emits less noise. The tire a with a tread having a small modulus of elasticity on a brick ground gives a small noise, but the overall noise difference is not very significant. Table 2 shows subjective feeling of the tester, and fig. 10 to 12 show specific noise data of the second test, fig. 10 is data of the test on a smooth and flat road surface, fig. 11 is data of the test on an asphalt road surface, and fig. 12 is data of the test on a brick floor. The data in the figure are consistent with the results in table 2 above.

Test three

The influence of the structure of the scroll 12 on the service life of the damping mute wheel is verified through three tests.

The following 4 damping mute wheels of the tire A, the tire B, the tire C and the tire D are respectively adopted for comparison test, and the number of the strips of the damping mute wheels is 18. The four tires are the same in size, specifically, the axial size is 40mm, the diameter is 153mm, and the tread thickness is 5 mm.

The cross-sectional area of the spoke of the tire A is the same at all places in the radial direction R; the modulus of elasticity of the rim is 4.6MPa, and the modulus of elasticity of the tread is 0.6 MPa.

The cross-sectional area of the two end portions of the web of the tire B in the radial direction R is larger than the cross-sectional area of the middle portion of the web 12, i.e., the same as the specific web structure described in the first embodiment. The modulus of elasticity of the rim is 4.6MPa, and the modulus of elasticity of the tread is 0.6 MPa.

Tire C is similar in construction to tire B, but the cross-sectional area of each portion of the spoke of tire C is smaller than tire B. The modulus of elasticity of the rim is 4.6MPa, and the modulus of elasticity of the tread is 0.6 MPa.

Tire D has the same structure as tire C, but the modulus of elasticity of the rim is 8.1MPa and the modulus of elasticity of the tread is 0.6 MPa.

The tires A, B, C, D were each mounted on the same table and a load was applied to the table to achieve a single wheel load of 30 kg. By pushing the table, the vibration condition and the noise condition of the table top are compared.

Then, a conveyor belt is built below the table, an obstacle is arranged on the conveyor belt, the height of the obstacle is 10cm, the length of the obstacle is 10cm, the conveyor belt runs at the speed of 1m/s, tires can impact the obstacle four times per second, and the time of tire damage is recorded respectively.

TABLE 3

As can be seen from table 3, compared with the tire a and the tire B, the spoke structures of the tires are different, and by designing the spoke structures, the stress concentration of the spokes can be reduced, so that the service life of the tires can be prolonged. Compared with the tire B and the tire D, the tire D has higher rim elastic modulus and longer service life, and the tire D also reduces the size of the spoke along the circumferential direction in order to ensure that the compression amount of the tire B and the tire D is the same when bearing static load. Compared with the tire C and the tire D, which have the same structure, the elastic modulus of the material for forming the rim of the tire D is larger than that of the material for forming the rim of the tire C, so that the compression amount of the rim D under the static load is smaller than that of the rim C under the static load, and the service life of the tire D is longer.

Third embodiment

The shock-absorbing mute wheel of the third embodiment is similar to the overall structure of the shock-absorbing mute wheel of the first embodiment, and the same reference numerals are used for the same or similar structures as those of the first embodiment in the third embodiment, and detailed description is not given.

As shown in fig. 13, the outer layer 11 is provided with a reinforcing member 14, the reinforcing member 14 is annular, and the radial dimension of the reinforcing member 14 may be 0.5 mm to 5 mm. The reinforcing member 14 may be made of stainless steel, and by the traction of the banner 12, the stress on the banner 12 may be reduced, thereby improving the life of the tyre.

The material forming the reinforcing member 14 is made of a material having an elastic modulus of 500Mpa or more, preferably 2000Mpa or more, such as metal (including alloy) or plastic. The modulus of elasticity of the reinforcing member 14 can be measured using GB/T22315 if metal is used and ISO 527-1 if plastic is used for the reinforcing member 14. The rim 1 is made of an elastic material with an elastic modulus of less than or equal to 100Mpa, and the reinforcing member 14 can enhance the strength of the rim 1.

As shown in fig. 13, the cross section of the reinforcing member 14 may be a solid rectangle, but the present invention is not limited thereto, and the cross section of the reinforcing member may also be in other shapes such as "i" shape, "U" shape, etc. In a possible embodiment, the reinforcement 14 can also be made of metal mesh.

It will be appreciated that if the modulus of elasticity of the reinforcing member 14 is too low, which may affect the service life of the tire, the plastic reinforcing member 14 may be attached to the outer layer 11 using a two shot molding process or a two shot molding process, which may result in higher production efficiency. The reinforcing member 14 made of a metal material needs to be coated with an adhesive on the surface of the reinforcing member 14 to be connected to the outer layer 11, which results in low production efficiency, and therefore, the reinforcing member 14 is preferably made of a plastic material.

The reinforcing member 14 may be embedded within the outer layer 11, for example by placing the reinforcing member 14 in a mold in advance before casting to form the rim 11 or by two-shot molding, two-shot molding.

In other possible embodiments, the reinforcing member 14 may also be provided on the surface of the outer layer 11.

Test four

The effect of the reinforcement member 14 on the service life of the damped squelched wheel was verified by test four.

The tire A is formed by pouring a pouring material with the elastic modulus of 0.6MPa into a mold.

The tire B is formed by pouring a casting material having an elastic modulus of 0.6MPa into a mold, in which a reinforcing member 14 having a radial dimension of 1 mm is reserved, so that the reinforcing member 14 is embedded inside the outer layer 11.

The tire C is formed by pouring a casting material having an elastic modulus of 0.6MPa into a mold, in which a reinforcing member 14 having a radial dimension of 3mm is reserved, so that the reinforcing member 14 is embedded inside the outer layer 11.

The three tires are the same in size, specifically, the axial size is 13mm, and the diameter is 52 mm. Tires A, B, C were each mounted in the same luggage compartment with a single wheel load of 4 kg. And carrying out vibration reduction and noise test on different road surfaces in a dragging mode.

Then, a conveyor belt is built below the luggage case, an obstacle is arranged on the conveyor belt, the height of the obstacle is 3cm, the length of the obstacle is 3cm, the conveyor belt runs at the speed of 1m/s, tires can impact the obstacle four times per second, and the time of tire damage is recorded respectively.

Fig. 14 to 16 show specific noise data of the above test, fig. 14 is data of the test on a smooth and flat road surface, fig. 15 is data of the test on an asphalt road surface, and fig. 16 is data of the test on a brick floor surface. The data in the figure are consistent with the results in table 4 above.

TABLE 4

As can be seen from table 4, the presence or absence of the reinforcing member 14 and the radial dimension of the reinforcing member 14 have no significant effect on the damping and noise reduction, but have a certain effect on the service life of the tire. The tire a without the reinforcement has the shortest service life, the tires B and C with the reinforcement 14 have longer service lives, and the tire C with the reinforcement having the larger radial dimension has the longest service life.

Fourth embodiment

The shock-absorbing mute wheel of the fourth embodiment is similar to the overall structure of the shock-absorbing mute wheel of the first embodiment, and the same reference numerals are used for the same or similar structures as those of the first embodiment in the fourth embodiment, and detailed description is not given.

As shown in fig. 17 and 18, the tire includes a rim 1 and a hub 2, the rim 1 being attached to the radially outer side of the hub 2, the rim 1 and the hub 2 being attached together. The rim 1 comprises an outer layer 11, a banner 12 and a transition layer 13, the outer layer 11 is used for contacting with the ground, the banner 12 is positioned at the radial inner side of the outer layer 11, the transition layer 13 is positioned at the radial inner side of the banner 12, and the rim 1 is connected with the hub 2 through the transition layer 13. A plurality of the spokes 12 are arranged at intervals uniformly along the circumferential direction C, and the intervals between the spokes 12 make the rim 1 hollow.

The rim 1 and/or the hub 2 are/is connected with a baffle 15, and the baffles 15 cover the hollow spaces formed by the intervals between the banners 12.

The baffles 15 may be located at one or both axial ends of the rim 1, and in this embodiment, the baffles 15 are located at both axial ends of the rim 1. The axial dimension of the spokes 12 is smaller than the axial dimension of the transition layer 13 and/or the hub 2 and of the outer layer 11, so that one or both ends of the tyre form a recess 16 capable of accommodating the baffle 15.

In a possible embodiment, the tire further comprises a tread, which is connected to the radially outer side of the outer layer 11. The tread is made of an elastic material, the elastic modulus of the material of the tread is smaller than that of the material of the rim 1, and compared with a tire without the tread, the tire with the tread can have better vibration and noise reduction performance. The recesses 16 may be formed by the axial dimension of the banner 12 being smaller than the axial dimension of the transition layer 13 and/or the hub 2 and the axial dimension of the tread.

The baffle 15 may be made of an elastomeric material such as cast polyurethane, thermoplastic elastomer or vulcanized rubber, i.e. the baffle 15 may be an elastomeric baffle, and the baffle 15 may also be made of a hard material such as metal or plastic. The shield 15 and the rim 1 may be integrally formed, or the shield 15 may be separately formed and the shield 15 and the rim 1 and/or the hub 2 may be connected together by, for example, snapping, bonding, etc. For example, the shield is provided with a snap and the hub 2 is provided with a snap groove for receiving the snap.

In the embodiment in which the baffle 15 is formed separately, the baffle 15 is annular, the outer diameter of the baffle 15 is smaller than the inner diameter of the recess 16, and the difference between them is greater than twice the amount of deformation of the tire under a rated static load, avoiding noise and vibration caused by contact, collision, friction, etc. of the baffle 15 and the recess 16 after deformation of the tire.

It will be appreciated that in at least some environments, such as windy environments, the passage of air through these openings can produce noise as the tire rotates, and the noise can be reduced by the shield 15 covering these openings.

Test five

The influence of the baffle 15 on the damping and silencing effect is verified through five tests.

Tyre a, a material having a modulus of elasticity of 4.6MPa, formed into a rim 1 having an axial dimension of 12mm and a diameter of 47 mm. The material with a modulus of elasticity of 0.6MPa forms the tread 3, the axial dimension of which is 13mm and the diameter of which is 52 mm.

The tire B has a baffle 15 made of a material having an elastic modulus of 0.6MPa, and the baffle 15 is attached to one axial end of the tire a.

The tire C has baffles 15 made of a material having an elastic modulus of 0.6MPa, and the baffles 15 are attached to both axial ends of the tire a.

The three tires are the same in size, and the tire A, the tire B and the tire C are respectively assembled in the same trunk, the single-wheel load is 4kg, the tires are towed on different road surfaces, and the vibration and the generated noise of a handle of the trunk are tested.

Fig. 19 to 21 show specific noise data of the above test, fig. 19 is data of the test on a smooth and flat road surface, fig. 20 is data of the test on an asphalt road surface, and fig. 21 is data of the test on a brick floor surface.

In fig. 19 to 21, the horizontal axis represents frequency (in Hz), and the vertical axis represents the magnitude of noise in dBSPL (i.e., sound pressure in decibels as a measurement quantity). As can be seen from the data of fig. 19 to 21, the noise of the tire C is significantly smaller than that of the tires a and B, and particularly, the noise of the tire C is smaller in a frequency band (1000 hz to 3000 hz) where the human ear is sensitive to sound. The noise difference between tyre a and tyre B is not significant and therefore it is preferred that the baffles 15 are located at both axial ends of the rim 1.

Claims

1. A damped silent wheel, comprising:

a hub (2), the hub (2) being annular;

the wheel rim (1) is fixedly connected to the radial outer side of the hub (2), the wheel rim (1) comprises an outer layer (11), banners (12) and a transition layer (13), the banners (12) are located on the radial inner side of the outer layer (11), the transition layer (13) is located on the radial inner side of the banners (12), the transition layer (13) is connected with the hub (2), the banners (12) are uniformly arranged at intervals along the circumferential direction (C) of the damping mute wheel, the intervals among the banners (12) enable the wheel rim (1) to be hollowed out, and the banners (12) are integrally bent to be of a C-shaped structure; and

the reinforcing member (14) is annular, the reinforcing member (14) is connected to the outer layer (11), and the elastic modulus of a material forming the reinforcing member (14) is larger than that of a material forming the rim (1).

2. A damped silent wheel according to claim 1, wherein the modulus of elasticity of the material forming said reinforcement (14) is greater than 500 Mpa.

3. A shock-absorbing silent wheel according to claim 1, characterized in that said reinforcement (14) is embedded inside said outer layer (11).

4. A damped silent wheel according to claim 1, wherein said reinforcement (14) is made of plastic, said reinforcement (14) being connected to said outer layer (11) using a two-shot process or a two-shot process.

5. A damped silent wheel according to claim 1, wherein said reinforcement (14) is made of metal, said metal being joined to said outer layer (11) by applying an adhesive to the surface of said reinforcement (14).

6. A damped mute wheel according to claim 1 wherein the circumferential dimensions of the two end portions of the web (12) in the radial direction (R) of the wheel are greater than the circumferential dimensions of the middle portion of the web (12).

7. A damped silent wheel according to claim 1, characterized in that it further comprises a tread (3), said tread (3) being connected radially on the outside of said outer layer (11), the modulus of elasticity of the material of said tread (3) being lower than the modulus of elasticity of the material of said rim (1).

8. The damped silent wheel according to claim 1, wherein the ratio of the displacement of the axial center (S) of the damped silent wheel to the radius of the damped silent wheel is 0.03 to 0.20 when the damped silent wheel is subjected to a rated static load.

9. A shock-absorbing silent wheel according to claim 1, characterized in that a baffle (15) is attached to said rim (1) and/or said hub (2), said baffle (15) covering said hollows formed by the spaces between said spokes (12).

10. A mobile apparatus, characterized in that it comprises a damped mute wheel according to any one of claims 1 to 9, the rated static load of a single damped mute wheel being less than 200 kg.