Coated ball screw backflow device and ball screw thereof

Abstract

The invention provides a coated ball screw backflow device and a ball screw thereof, and is applied to the technical field of ball screws. The backflow device is provided with a bent backflow channel used for guiding a plurality of balls to conduct backflow steering in the channel, and an inward end face which abuts against the inner wall of the nut in the axial direction and is used for axially positioning the backflow device. The outward end face and the inward end face are arranged on the two sides of the backflow device in the axial direction respectively, and the sound insulation pattern is formed on the outward end face and at least roughly covers the projection area of the bent backflow channel on the outward end face in the axial direction. The sound insulation pattern comprises a plurality of sound insulation components which roughly extend outwards from the outward end face, at least some of the sound insulation components are arranged and separated into air gaps with gas thin film damping, and the air gaps are limited between the main side surfaces of the adjacent components, so that noise and structural resonance generated when the backflow device works can be effectively absorbed.

Description

Technical Field

[0001] The present application relates to the technical field of ball screw transmission, and in particular to a coated ball screw reflow device and a ball screw thereof. Background Art

[0002] It is known that when the ball screw is in transmission, the rows of balls move in the circulation path between the screw and the nut, which will cause a certain degree of low-frequency noise. In some cases, these noises are about 60-90 dB, and the frequency can reach 200-400 Hz. As one of the disclosed known technologies, the patent with publication number TW201122271A and the name of the ball screw with a silencer has pointed out that for the end plug type ball screw, there are two main propagation paths for its noise. One is the ball load channel sound source, which propagates outward through the gap between the screw and the nut in the radial direction and extends to the end in the axial direction. The second is the ball reflow device sound source. Since the rows of balls need to turn through the reflow channel in the reflow device, some undesirable extrusion, collision and friction will inevitably occur in the channel. The superposition of these factors causes the ball reflow device to become another important noise source when the ball screw is running, and it will propagate outward along the medium on the adjacent nut end side.

[0003] In the disclosed technology, in order to solve this problem, a silencer consisting of a sound inlet, a sound guide plate and a silencer cover is arranged on the end side of the nut. The sound inlet and the sound guide plate cooperate to conduct the noise to the annular bottom surface with a sound absorbing part on the silencer cover. The sound absorbing part reflects the noise and interferes with the sound waves of the subsequent noise, thereby achieving the technical purpose of eliminating the noise. However, the structure of the silencer is too complicated, which is not only reflected in the large number of assembled parts, but also in the complex processing and manufacturing. In order to achieve ideal reflection and interference control of sound waves, the structure and position of the sound absorbing part, the material, number and position of the sound guide plate and the shape of the sound inlet all need to be specially and strictly designed, which makes the assembly requirements high and the manufacturing cost high, which is not conducive to mass production.

[0004] Among the disclosed technologies, in order to solve the above-mentioned noise problem, the patent with publication number CN101943252A and name of honeycomb structure ball deflector adopts another method, that is, adding a honeycomb matrix on the outside of the deflector, that is, the reflow device. When the ball screw pair is working, the ball enters the ball reflow device from the spiral raceway, and the ball rubs and collides with the inner wall of the reflow channel. The interlaced honeycomb matrix can dissipate a lot of energy and play a damping role, and the vibration energy generated is absorbed, thereby achieving the effect of reducing noise and friction. Since the honeycomb matrix needs to be attached to the outer surface of the reflow device, and the two need to be fixed by bonding or hot-melt welding, there are still problems of complex structure, high assembly requirements and high manufacturing cost.

[0005] In the disclosed technologies, in order to solve the above-mentioned noise problem, a large number of sound-absorbing holes are provided on the inner wall of the spiral rolling groove of the nut or the inner wall of the spiral rolling groove of the screw, and porous materials such as sound-absorbing cotton and sound-absorbing rods are provided in at least some of the sound-absorbing holes. Although the vibration and noise during screw transmission can be suppressed to a certain extent, there are problems such as complex structure, difficult processing and manufacturing, high cost, and poor targeting.

[0006] In addition, it has been learned that the absorption of noise through the scattering and interference of sound waves in porous materials with sound-absorbing holes or sound-absorbing parts is beneficial to the absorption of high-frequency noise, while it is more difficult to absorb low-frequency noise. Taking the absorption of noise below 400Hz as an example, according to the formula: where f c is the critical frequency, in Hz. Below this critical frequency, the sound absorption coefficient of the material will drop significantly. c is the speed of sound, which is about 343 m / s in air. d is the required thickness of the porous material. Let f c Taking 400Hz, we approximately calculate the thickness d of the required porous material, and the result is d≈0.14m, which means that for noise with a frequency below 400Hz, in order to achieve the ideal noise absorption effect, the required material thickness must be at least 0.14m, and as the frequency decreases, the required material thickness must also increase accordingly. In general, the overall length size range of the nut in an end-plug ball screw is approximately tens of millimeters to hundreds of millimeters, and the overall installation size range of the end-side components is only a few millimeters to tens of millimeters. This means that if the above-mentioned porous material is used to block the propagation of noise of the end-plug ball reflow device in the axial direction of the nut, the following technical contradiction will arise, that is, if the thickness of the porous material is reduced to adapt to the axial installation size of the nut, the noise absorption effect will be worse, and if the thickness of the porous material is increased to achieve the ideal noise absorption effect, too much axial installation space inside the nut will be occupied, making the design of the installation position of the end-side components including the scraper difficult, and causing the load distribution of the nut on the screw to become uneven.

[0007] In summary, at present, there are at least the following technical problems that need to be overcome or solved, namely, how to achieve a better or desired suppression or absorption effect on the low-frequency noise generated in the ball recirculator without adding additional components, while minimizing the axial installation size inside the nut occupied by the sound-absorbing component, so as to produce a more reasonable implementation plan that takes into account the three aspects of cost, function and size requirements. Summary of the invention

[0008] In view of this, an embodiment of the present specification provides an enclosed ball screw reflow device and a ball screw thereof, wherein the reflow device is mounted on a nut and has: a curved reflow channel for guiding a plurality of balls to perform reflow and deflection in the channel; an inward end face axially abutting against the inner wall of the nut for axial positioning of the reflow device; an outward end face disposed on both sides of the reflow device along the axial direction together with the inward end face; and a sound insulation pattern formed on the outward end face and at least roughly covering the projection area of ​​the curved reflow channel on the outward end face in the axial direction; wherein the sound insulation pattern includes a plurality of sound insulation components extending roughly outward from the outward end face and at least some of the plurality of sound insulation components are arranged and separated to define an air gap with gas film damping between the main side surfaces of adjacent components.

[0009] In order to optimize the above scheme, the following technical measures are also taken:

[0010] Preferably, the air gap with gas film damping is an air gap with a depth-to-width ratio of at least about 0.3:1.

[0011] As a preferred embodiment, the width of the air gap is 0.2 to 3.5 mm.

[0012] Preferably, the returner is made of an organic polymer material having a density of at least about 0.8 g / cc.

[0013] As a preferred manner, the sound insulation pattern is formed on the outer wall of the reflow device by molding, printing or etching.

[0014] As a preferred embodiment, the sound insulation pattern includes an inward recess formed on the outer wall of the returner, and the outward end surface is the bottom surface of the inward recess.

[0015] Preferably, at least some of the sound insulating members are in the form of outwardly extending elongate ribs, at least some of the elongate ribs being arranged and spaced so as to define the air gap between major side surfaces of adjacent ribs.

[0016] As a preferred embodiment, at least some of the sound insulation components are in the form of slender ribs extending outward, and the slender ribs include a plurality of longitudinal ribs and transverse ribs, which divide the plurality of longitudinal ribs and transverse ribs into a plurality of independent compartments on the outward end surface, and the spacing between at least two opposite rib walls of at least some of the compartments is designed so that the frequency of the standing wave that can be generated within the spacing is greater than the frequency of the sound wave generated by the return device within the spacing when the return device is working.

[0017] Preferably, at least some of the compartments are formed with at least one fractal rib extending roughly outward from the outward end surface, and at least some of the fractal ribs are arranged to define the air gap between the main side surfaces of adjacent ribs or between their respective main side surfaces and the corresponding compartment rib walls.

[0018] Preferably, at least some of the compartments are formed with at least one fractal column extending roughly outward from the outward end surface, and at least some of the fractal columns are arranged to define the air gap on the main side surfaces of adjacent columns or between their respective main side surfaces and the corresponding compartment rib walls.

[0019] Preferably, at least some of the soundproofing members are in the form of outwardly extending columns having at least three major side surfaces, at least two of the at least three major side surfaces each defining an air gap between the major side surface and a major side surface of an adjacent member.

[0020] Preferably, the ratio of the solid volume occupied by at least some of the two adjacent sound insulation members forming the air gap to the volume occupied by the air in the corresponding air gap is at least about 4:1.

[0021] The present embodiment further provides a ball screw, comprising: a screw; a nut surrounding the screw, which has a ball return channel extending axially therethrough and an embedding groove at each end thereof; a plurality of balls which are freely arranged to roll in a ball load channel formed by the spiral rolling grooves of the screw and the nut; and a pair of recirculators, each of which is embedded in the embedding grooves at both ends of the nut and connects the ball load channel and the ball return channel to form a ball circulation path; wherein the recirculator adopts the above-mentioned ball screw recirculator.

[0022] In order to optimize the above scheme, the following measures are also taken:

[0023] As a preferred embodiment, the reflux device is composed of a first part and a second part which are snap-connected to each other, wherein the first part has a first reflux groove and a tongue portion formed at one end of the first reflux groove, the tongue portion being constructed to extend toward the ball load channel so as to be suitable for picking up the balls from the ball load channel and guiding them into the first reflux groove, and the second part has a second reflux groove, which together with the first reflux groove defines the curved reflux channel.

[0024] As a preferred embodiment, the second reflux groove includes a first cross-sectional segment and a second cross-sectional segment, the first cross-sectional segment is engaged with the ball load channel and the first cross-sectional segment is constructed as a Gothic tooth profile, the second cross-sectional segment is engaged with the ball return channel and the second cross-sectional segment is constructed as an arc tooth profile, and a smooth transition is adopted between the first cross-sectional segment and the second cross-sectional segment.

[0025] As a preferred embodiment, the outward end surface is formed on the second part, and the inward end surface is formed on the first part or the second part.

[0026] As a preferred embodiment, an annular groove is formed at each end of the nut, and the ball screw also includes an end side component installed in each of the annular grooves, the embedding groove is formed by the bottom surface of each annular groove of the nut being recessed inward along the axial direction, and the reflux device embedded in the embedding groove abuts between the corresponding embedding groove and the end side component along the axial direction to achieve axial positioning of the reflux device.

[0027] As a preferred embodiment, the sound insulation pattern on the returner is positioned in a substantially closed space formed between the returner and the end side component.

[0028] As a preferred manner, the returner is further formed with a positioning end surface abutting against the corresponding end side component, and one end of at least some of the sound insulation components on the sound insulation pattern is flush with the positioning end surface.

[0029] As a preferred embodiment, the end side component includes a wiper component, and the inner ring of the wiper component is in sealing contact with the rolling groove of the screw.

[0030] Compared with the prior art, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0031] First, a sound insulation pattern is directly formed on the outward end face of the ball screw reflow device, and it is ensured that the sound insulation pattern roughly covers the projection area of ​​the curved reflow channel on the outward end face along the axial direction. Multiple air gaps with gas film damping formed in the sound insulation pattern are utilized to absorb the noise and structural resonance generated when the reflow device is working. On the basis of achieving the sound absorption and vibration reduction effects, there is no need to set up additional redundant parts, thereby reducing the processing and manufacturing cost of the screw.

[0032] Secondly, unlike the solution of using porous sound-absorbing materials in the prior art, this solution utilizes multiple air gaps with gas film damping formed between the sound insulation components to absorb sound and reduce noise. It does not rely on the thickness of the material, but uses the viscous resistance of air to dissipate vibration energy. Therefore, the axial installation dimension of the nut occupied by the sound insulation pattern is smaller, which can leave space for the installation and positioning of the end side components. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 is a schematic diagram of the back structure of the reflux device in the first embodiment of the present application;

[0035] Figure 2 It is a schematic diagram of the main structure of the reflux device in the first embodiment of the present application;

[0036] Figure 3 It is a schematic diagram of the combined structure of the reflux device and the nut in the first embodiment of the present application;

[0037] Figure 4 It is a schematic diagram of the disassembled structure of the reflux device and the nut in the first embodiment of the present application;

[0038] Figure 5 It is a structural schematic diagram of some parts of the reflux device in Example 1 of the present application;

[0039] Figure 6 It is a cross-sectional schematic diagram of some parts of the reflux device in the first embodiment of the present application;

[0040] Figure 7 This is a schematic diagram of the structure in the compartment of the reflux device in Example 1 of the present application;

[0041] Figure 8 It is a schematic diagram of the main structure of the reflux device in the second embodiment of the present application;

[0042] Fig. 9 is a schematic cross-sectional structure diagram of the reflux device in the third embodiment of the present application;

[0043] Fig.10 It is a schematic diagram of the disassembled structure of the reflux device in Example 1 of the present application;

[0044] Fig.11 is a schematic diagram of the disassembled structure of the reflow device in the first embodiment of the present application from another perspective;

[0045] Fig.12 This is a schematic diagram of the structure of the inner end side of the reflux device in the first embodiment of the present application;

[0046] Fig.13 This is a schematic diagram of the structure of the reflux device toward the outer end in the first embodiment of the present application;

[0047] Fig.14 is a schematic diagram of the structure of the ball screw in the first embodiment of the present application;

[0048] Fig.15 This is a schematic diagram of the structure of the ball screw after removing the reflow device in the first embodiment of the present application;

[0049] Fig.16 It is a schematic diagram of the disassembled structure of the ball screw in the first embodiment of the present application;

[0050] Fig.17 is a schematic diagram of the cross-sectional structure of the ball screw in the first embodiment of the present application;

[0051] Fig.18 is a schematic diagram of the side cross-section structure of the ball screw in the first embodiment of the present application;

[0052] Fig.19 It is a schematic diagram of the coordination between the ball and the return device in the first embodiment of the present application. Description of the drawings:

[0054] 10. Reflux device; 1. Shell; 11. First part; 111. First reflux groove; 112. Tongue part; 113. Conduit part; 114a. First parting surface; 114b. Second parting surface; 115. First wing; 116. First clamping part; 117. Second clamping part; 12. Second part; 120. Second reflux groove; 121. First cross-sectional section; 122. Second cross-sectional section; 125. Second wing; 126. First joint; 127. Second joint; 128. Ear plate ; 13. Inward end face; 14. Outward end face; 15. Return channel; 2. Sound insulation pattern; 21. Sound insulation member; 210. Main side surface; 211. Slender ribs; 211a. Longitudinal ribs; 211b. Transverse ribs; 212. Column; 22. Air gap; 23. Compartment; 231. Fractal ribs; 232. Fractal column; 30. Nut; 31. Ball load channel; 32. Ball return channel; 33. Annular groove; 34. Embedding groove; 40. Screw; 50. Ball; 60. End side component. DETAILED DESCRIPTION

[0055] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0056] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0057] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0058] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0059] The embodiments of this specification propose a coated ball screw reflow device and a ball screw thereof, aiming to solve the problems in the prior art that the noise suppression or absorption device for the ball screw reflow device has a large number of parts, a complex structure and a poor low-frequency noise absorption effect. While achieving a better suppression or absorption effect on the low-frequency noise generated on the ball screw reflow device, no additional parts are added, that is, the ball screw reflow device itself has the effect of suppressing or absorbing noise, thereby reducing the processing and manufacturing costs of the noise-reducing ball screw.

[0060] The technical solutions provided by various embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0061] Embodiment 1

[0062] like Figures 1 to 6As shown, the enclosed ball screw reflow device 10 is mounted on the nut 20, and the reflow device has a curved reflow channel 15 for guiding a plurality of balls 50 to perform reflow diversion in the channel, an inward end face 13 axially abutting against the inner wall of the nut 30 for axial positioning of the reflow device, an outward end face 14 axially arranged on both sides of the reflow device 10 with the inward end face 13, and a sound insulation pattern 2 formed on the outward end face 14 and at least roughly covering the projection area of ​​the curved reflow channel 15 on the outward end face 14 in the axial direction, wherein the axial direction refers to the axial direction of the nut 30 or the screw 40, as shown in FIG. Figure 3 As shown, the axial direction S1 of the screw is shown. In some cases, the backflow diversion may refer to the process of the plurality of balls 50 being transferred from the ball load channel 31 extending substantially perpendicular to the axial direction of the screw between the screw 40 and the nut 30 to the ball return channel 32 extending along the axial direction of the nut 30. In other cases, it may also refer to the process of returning from the ball return channel 32 to the ball load channel 31. Figure 1 As shown, here, the inward end face 13 is a plane formed on the outer wall of the reflux device 10. The inward end face 13 refers to the end face facing the inner cavity of the nut 30 along the axial direction of the nut 30, and the outward end face 14 is opposite to it. The outward end face 14 and the inward end face 13 are "separated on both sides of the reflux device 10" along the axial direction, that is, the outward end face refers to the end face facing the outer end of the nut 30 along the axial direction of the nut 30. Figure 3 and Figure 4 The figure roughly shows the situation where the return device 10 is assembled to the nut 30. The sound insulation pattern 2 is arranged on the outward end surface 14. The purpose is to place the sound insulation pattern 2 on the axial propagation path of the sound waves and vibrations generated by the return device 10 to prevent the sound waves and vibrations from being transmitted axially to the outer end of the nut 30.

[0063] in, Figure 2 and Figure 5 The area divided by the substantially closed dotted line is the area where the sound insulation pattern 2 is located, and the sound insulation pattern 2 includes a plurality of sound insulation members 21 extending substantially outward from the outward end surface 14, and at least some of the plurality of sound insulation members 21 are arranged and separated to define an air gap 22 with gas film damping between the main side surfaces 210 of adjacent members. Figure 2 , Figure 5 and Figure 6As shown, the concept of "graphic" in the sound insulation graphic 2 is suitable for the following explanation, that is, a structure with a smaller thickness dimension attached to a certain integral component and composed of a plurality of structures such as ribs, ridges, columns, walls or grids with predetermined shapes and sizes can be included in the category of the "graphic". For example, a mold "graphic" composed of ribs or ridges or grids arranged in a regular or irregular manner on a molding mold, or a conductive "graphic" processed on a printed circuit board by etching. In this embodiment, the structure with sound insulation function formed on the outward end face 14 is summarized as a "sound insulation graphic" mainly based on the following considerations. On the one hand, the "sound insulation graphic" has a smaller thickness dimension in the axial direction relative to the wall thickness of the returner 10, such as Figure 6 and Fig.17 As shown, from the cross-section, it looks like a two-dimensional planar structure formed on the reflow device 10. On the other hand, it is intended to emphasize that the "sound insulation pattern" is a structure attached to the reflow device 10, and is not a separate component, such as a "honeycomb sound-absorbing layer". The difference between the two will be described in detail below. Furthermore, similar to the "mold pattern", the "sound insulation pattern" described here can be molded, and in some methods, etching or 3D printing can also be used. Further, the "pattern" can be molded into a predetermined shape and size, and the shape of the "pattern" can be changed as needed, so as to achieve functional control of, for example, the "sound insulation function".

[0064] Here, the sound insulation component 21 can be a component such as a rib, a ridge, a column, a wall or a grid. It is known that by forming and maintaining an extremely thin air layer between two opposite solid plate surfaces, the effect of reducing the vibration and sound radiation of the plate surface can be achieved. The main principle is to quickly pump the air vibration in the air layer through the vibration of the plate, and the viscous damping effect of the air layer dissipates the vibration energy, thereby reducing the vibration and sound radiation of the panel. The damping generated by the coupling of the solid and air fluid vibrations is also called gas film damping or pumping damping. This embodiment utilizes this principle, so that at least some of the multiple sound insulation components 21 are arranged and separated to define an air gap 22 with gas film damping between the main side surfaces 210 of adjacent components. When the reflow device 10 is working, the multiple balls 50 pass through the curved reflow channel 15 on the reflow device 10, and the generated vibration or noise is transmitted to the multiple sound insulation components 21 on the sound insulation pattern 2 through the outer wall of the reflow device. The energy of the generated vibration or noise can be quickly dissipated through the air viscosity resistance in the air gap 22 with gas film damping. The superposition effect of the multiple air gaps 22 can achieve a significant sound absorption effect. Since the sound insulation pattern 2 is configured to at least roughly cover the projected area of ​​the curved reflow channel 15 on the outward end surface 14 in the axial direction, it is difficult for the noise generated in the reflow channel 15 to "slide" through the periphery of the sound insulation pattern 2, so that it can play a better blocking role in the propagation of the noise generated in the entire reflow channel 15 in the axial direction of the nut 30. Furthermore, in addition to the sound absorption effect of the gas film damping generated in the air gap 22, the sound waves of the noise will also generate greater friction losses due to scattering between the main side surfaces when passing through the main side surfaces of the sound insulation component 21, and some noise in the air can also be absorbed by utilizing the thermal viscosity effect. The integration of factors such as these generally limits the overall sound insulation effect and capacity of the sound insulation pattern 2.

[0065] Those skilled in the art should recognize that the use of such an air gap structure with gas film damping to achieve the absorption of the vibration and noise belongs to the disclosed technical means, however, the present embodiment applies this technical means to the ball screw reflow device 10 and can eliminate the following technical contradiction, namely, the contradiction between the thickness setting of the sound absorbing layer structure and the sound absorbing effect. That is to say, in the present embodiment, by optimizing the structure of the sound insulation pattern 2, such as reducing the width of at least some air gaps, increasing the number of at least some air gaps, changing the thickness and mass of at least some sound insulation components 21, etc., the effect of the sound insulation pattern 2 in absorbing vibration and noise can be improved without necessarily increasing the thickness of the sound insulation pattern 2, thereby saving the axial installation dimension of the nut 30, so as to facilitate the installation and positioning design of the end side components. In addition, it has been shown in the present embodiment that the sound insulation pattern 2 is a part attached to the reflow device 10. In some embodiments, the sound insulation pattern 2 and the reflow device 10 can be integrally molded, or the sound insulation pattern 2 can be processed on the outer wall of the reflow device 10 by uncommon printing or etching methods. Therefore, the present embodiment achieves the effect of absorbing the vibration and noise generated by the reflow device 10 during operation, and does not use additional components related to the sound insulation or sound absorption function other than the reflow device 10, which reduces the difficulty and cost of processing and manufacturing the ball screw.

[0066] In some specific embodiments, the air gap 22 with gas film damping is an air gap with a depth-to-width ratio of at least about 0.3: 1. Furthermore, the width of the air gap is 0.2-3.5 mm, and the depth of the air gap is 1-1.2 mm. When the air gap width is 0.2 mm and the air gap depth is 1 mm, the air gap with gas film damping is an air gap with a high depth-to-width ratio of 5: 1. In an air gap with a high depth-to-width ratio, i.e., a deep and narrow air gap, on the one hand, as the air pressure increases, the air viscosity resistance will also increase, and on the other hand, the sound wave is more likely to abut against the main side surface 210 forming the air gap, so that the friction loss experienced by the sound wave is greater and the sound absorption effect is better. When the air gap width is 3.0 mm and the depth is 1 mm, the air gap with gas film damping is an air gap with a smaller aspect ratio of 0.3:1. The reduction in the aspect ratio is mainly caused by the following factors. In some cases, the wall thickness of the reflow device 10 is relatively small. In order to prevent the structural strength of the reflow device 10 from being affected, the depth values ​​of some air gaps on the sound insulation pattern 2 need to be set to a smaller value, so that the value of the air gap aspect ratio is also relatively small, which reduces the ability or effect of the air gap to absorb or suppress noise. However, it is still possible to achieve a more desired sound absorption effect through the operation of some number mechanisms in a given sound field. In some cases, due to the constraints of the structure and position of some sound insulation components 21, the width of the air gaps between some main side surfaces 210 is smaller, while the width of the air gaps between other main side surfaces 210 is larger, such as Figure 7As shown, d1 to d10 show various situations of the width dimension of the air gap under an embodiment, and the specific structure will be described in detail below. For example, the air gap formed between the main side surface 210 of the sound insulation member 21 configured in the form of a T-shaped rib and the rib wall of the compartment 23 has a width dimension d5 or d7, and the width dimension d5 or d7 is greater than the other values ​​of d1 to d10. Therefore, when the air gap depth value is constant, the value of the depth-to-width ratio of the corresponding air gap is smaller, but it is still possible to increase the attenuation of unwanted noise by generating some sound wave scattering, friction loss and thermal viscosity effect between these air gaps. It should be recognized that, under the permission of setting conditions such as the wall thickness value of the returner 10, the maximization of the aspect ratio of at least some air gaps can be pursued to achieve the best noise absorption effect of a single air gap. However, this should also take into account the number mechanism of the air gap structure in the entire sound insulation pattern 2, that is, the influence of the number of air gaps that can be formed on the noise absorption of the pattern. For example, for the above-mentioned sound insulation member 21 in the form of a T-shaped rib, although the air gap formed between the main side surface 210 at the leg and the compartment rib wall has a smaller aspect ratio, the multiple main side surfaces 210 of the sound insulation member 21 can form the air gap with the main side surface of the adjacent rib, so that a plurality of the air gaps can be formed in one compartment 23, and the increase in the number of air gaps is positively correlated with the overall sound absorption performance of the sound insulation pattern 2. However, it should be noted that as the width of the air gap increases, the air pressure in the air gap decreases, and the corresponding air viscosity resistance decreases. In this embodiment, the width of the air gap has an upper limit of 3.5 mm, that is, when the width is higher than this value, the sound absorption performance of the air gap will show an unexpected significant decrease.

[0067] In this embodiment, the reflow device 10 is made of an organic polymer material having a density of at least about 0.8 g / cc, and more preferably, it is made of an organic polymer material having a density of at least about 1.0 g / cc, which further illustrates that the reflow device 10 in this embodiment does not use a porous sound-absorbing material. The organic polymer material may include a molding resin, whether it is a thermoplastic or thermosetting resin, and may be selected from, for example, polyurethane, polypropylene, polyethylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyester, polyamide, polyoxymethylene, siloxane polymer, acrylonitrile-butadiene-styrene polymer, polyphthalamide, etc., and any mixture, copolymer and / or blend of these materials may be used, and any such material may include various additives, such as fillers, reinforcing agents, antioxidants, colorants and pigments, etc. This material may be formed by any suitable means to process the main body of the reflow device 10, such as injection molding, vacuum molding, gravity-assisted molding, slush molding, etc. In some embodiments, the sound insulation pattern 2 may also be made by an additive manufacturing process (commonly referred to as 3D printing), which uses any organic polymer resin suitable for such processing. In various embodiments, the material of the body may have a Shore A hardness of 30-100.

[0068] In some cases, the sound insulation pattern 2 includes an inwardly-facing recessed portion formed on the outer wall of the returner 10, and the outwardly-facing end surface 14 is the bottom surface of the inwardly-facing recessed portion. Figure 2 As shown, the specific position of the outer end surface 14 is roughly shown. Figure 2 and Figure 6 From the perspective of the embodiment, the outward end surface 14, i.e., the bottom surface of the formed compartment 23, can be roughly regarded as a plane.

[0069] In this embodiment, at least some of the soundproofing members 21 are in the form of outwardly extending elongated ribs 211, where at least some of the elongated ribs 211 are arranged and spaced to define the air gap 22 between the major side surfaces 210 of adjacent ribs. Specifically, the elongated ribs 211 include a plurality of longitudinal ribs 211a and transverse ribs 211b, which divide a plurality of independent compartments 23 on the outward end surface 14, and the ratio of the longest dimension of the ribs (e.g., the length of the ribs) to their shortest dimension (e.g., the width or thickness of the ribs) in the longitudinal ribs or transverse ribs forming the compartments 23 is 4:1 or greater. In various embodiments, such elongated ribs may have a longest / shortest dimension ratio of at least about 6:1, 8:1, 10:1, or 15:1. The spacing between at least two relative rib walls of at least some of the compartments 23 is designed so that the frequency of the standing wave that can be generated within the spacing is greater than the frequency of the sound wave generated by the return device 10 within the spacing when it is working. In this way, the sound wave frequency of the noise generated by the return device 10 when it is working cannot generate standing waves within the spacing, thereby obtaining some undesirable enhancement of sound waves. According to the conditions for the formation of standing waves, the frequency (fundamental frequency) of the standing wave is inversely proportional to the size of the above-mentioned spacing. Therefore, reducing the spacing between the above-mentioned relative rib walls can increase the frequency of the standing wave, that is, the noise frequency below this frequency cannot generate standing waves between the relative rib walls of the above-mentioned compartment 23, thereby preventing the occurrence of undesirable enhancement of sound waves.

[0070] In this embodiment, at least some of the compartments 23 are formed with at least one fractal rib 231 extending substantially outward from the outward end surface 14, and at least some of the fractal ribs 231 are arranged to define the air gap between the main side surfaces of adjacent ribs or between the main side surfaces of the respective ribs and the rib wall of the corresponding compartment 23. Figure 5 and Figure 6 As shown, at least some of the fractal ribs 231 are roughly T-shaped, specifically including a longitudinal section and a transverse section (i.e., the aforementioned legs), the transverse section can be arranged relatively parallel to the corresponding transverse rib 211b, and the longitudinal section can be arranged relatively parallel to the corresponding longitudinal rib 211a, wherein one end of the transverse section can be engaged with the corresponding longitudinal rib 211a, and the fractal rib 231 has roughly 7 main side surfaces, wherein each main side surface can define the air gap with gas film damping between the main side surface of the adjacent rib or the rib wall of the adjacent compartment. Figure 7As shown, d1 to d10 generally show the width dimensions of 10 air gaps formed in a compartment 23, wherein the compartment 23 has two fractal ribs 231 that are staggered in the longitudinal direction and arranged in a mirror image in the transverse direction, d6 is an air gap with gas film damping defined by the main side surfaces of the longitudinal sections of the two fractal ribs 231, d3 and d8 are the air gaps defined by the longitudinal sections of each fractal rib 231 and the rib wall of the compartment 23, d1 and d7 are the air gaps defined by the main side surfaces of the legs of the fractal rib 231 and the rib wall of the compartment 23, and the formation methods of the other air gaps are generally similar to the above-mentioned air gaps, which will not be described in detail here. However, it should be noted that this is only an exemplary description, and in fact there are still some air gaps that are formed that are not shown, but based on this exemplary description, technicians should be able to understand the general idea of ​​forming the air gap structure and find all of them in the accompanying drawings accordingly. Compared with rectangular columns or rectangular ribs, the T-shaped ribs can form a larger number of air gaps, which is more conducive to improving the sound absorption effect from the perspective of the mechanism for forming the number of air gaps. Some special-shaped ribs are located at the inner edge of the inward recess and can be configured to have at least two main side surfaces, at least some of which form air gaps with the main side surfaces of adjacent ribs.

[0071] In this embodiment, the structure and position of the sound insulation component 21 can also be limited in the following manner, that is, the ratio of the solid volume occupied by at least some adjacent sound insulation components 21 forming the air gap 22 to the volume occupied by the air in the corresponding air gap 22 is at least about 4:1. In some embodiments, this value can be 6:1, 8:1, 10:1, 15:1, 20:1, 30:1 or 40:1.

[0072] like Figures 14 to 18 As shown, on this basis, the present embodiment further proposes a ball screw, comprising a screw 40, a nut 30 surrounding the screw 40 and having a ball return channel 32 formed along the axial direction and an embedding groove 34 formed at each end along the axial direction, a plurality of balls 50 rolling freely arranged in a ball load channel 31 surrounded by the spiral rolling grooves of the screw 40 and the nut 30, and a pair of reflow devices each embedded in the embedding grooves 34 at both ends of the nut 30 and connecting the ball load channel 31 and the ball return channel 32 to form a ball circulation path, wherein the reflow device adopts the ball screw reflow device 10 as described above.

[0073] In this embodiment, reference Fig.10As shown, the housing 1 of the reflux device 10 is composed of a first part 11 and a second part 12 that are snap-connected to each other, wherein the first part 11 has a first reflux groove 111 and a tongue portion 112 formed at one end of the first reflux groove 111, the tongue portion 112 is constructed to extend toward the ball load channel 31 so as to be suitable for picking up the balls 50 from the ball load channel 31 and guiding them into the first reflux groove 111, the other end of the first reflux groove 111 is a conduit portion 113, the conduit portion 113 is constructed to extend toward the ball return channel 32 so as to be suitable for guiding a plurality of balls 50 from the reflux channel 15 to the ball return channel 32, the second part 12 has a second reflux groove 120, and the second reflux groove 120 and the first reflux groove 111 together define the curved reflux channel 15.

[0074] like Figure 10 to Figure 11 As shown, specifically, the first part 11 has a first parting surface 114a extending substantially along the longitudinal direction of the reflow channel 15 and perpendicular to the channel, and the second part 12 has a second parting surface 114b extending radially along the reflow channel 15 and slightly concave toward the outward end surface 14. The reflow device 10 in this embodiment is divided into two parts from the first parting surface 114a and the second parting surface 114b and molded separately, and then combined into an integral part. The split-mold manufacturing makes the processing and manufacturing processes more efficient and quick. A first clamping portion 116 is also provided on the first part 11 at a position corresponding to the second parting surface 114b, and a first combining portion 126 matching the first clamping portion 116 is also provided on the second part 12 on the second parting surface 114b. Here, the first clamping portion 116 and the first combining portion 126 can be clamped in a manner such as an embedding block and a groove. Similarly, a second clamping portion 117 is provided on the first part 11 on the first parting surface 114a, and a second combining portion 127 matching the second clamping portion 117 is also provided on the second part 12 at a position corresponding to the first parting surface 114a. Here, the second clamping portion 117 and the second combining portion 127 can be clamped in a manner such as an embedding block and a groove. The combined assembly of the two parts is achieved by the clamping structure provided on the two parting surfaces.

[0075] As a detail, the first part 11 has a first wing 115 extending in an arc shape, and the second part 12 has a second wing 125 extending in an arc shape. When the first part 11 and the second part 12 are assembled, the first wing 115 and the second wing 125 form an arc surface that is suitable for having a curvature substantially the same as that of the outer diameter surface of the screw 40. Further, the outward end surface 14 is formed on the second part 12, and the inward end surface 13 is formed on the first part 11 or the second part 12. In this embodiment, the first part 11 has a first plane portion, and the second part 12 has a second plane portion. When the reflux device 10 is assembled into the embedding groove 34, the first plane portion and the second plane portion are relatively flush and jointly define the inward end surface 13, and the inward end surface 13 abuts against the bottom surface of the embedding groove 34.

[0076] Specifically, refer to Fig.19 As shown, the second reflux groove 120 includes a first cross-sectional section 121 and a second cross-sectional section 122, the first cross-sectional section 121 is connected to the ball load channel 31 and the first cross-sectional section 121 is configured as a Gothic tooth profile, i.e., a pointed arch groove, the second cross-sectional section 122 is connected to the ball return channel 32 and the second cross-sectional section 122 is configured as an arc tooth profile, and a smooth transition is adopted between the first cross-sectional section 121 and the second cross-sectional section 122. By setting the first cross-sectional section 121 of the Gothic tooth profile, the step difference between the connected channels can be reduced, so that the ball 50 is relatively stable when flowing from the ball load channel 31 into the reflux channel 15 or from the reflux channel 15 into the ball load channel 31, and the impact force is small, so that the vibration and noise generated are also relatively small.

[0077] In this embodiment, an annular groove 33 is formed at each end of the nut 30, and the ball screw further includes an end side component 60 installed in each of the annular grooves 33. The bottom surface of each annular groove of the nut 30 is recessed inwardly in the axial direction to form the embedding groove 34, and the returner 10 embedded in the embedding groove 34 abuts between the corresponding embedding groove 34 and the end side component 60 in the axial direction to achieve axial positioning of the returner 10. In the axial direction, the notch of the embedding groove 34 is roughly in the shape of a keyway, and such a regular contour setting is conducive to saving the finishing time for the end face of the nut 30. The sound insulation pattern 2 on the returner 10 is positioned in a substantially closed space formed between the returner 10 and the end side component 60. Thereby, the air gap on at least a part of the sound insulation pattern 2 is formed as a closed air gap, and this air gap can absorb at least some air sound, for example, through friction or thermal viscosity effect. That is, the sound waves entering such an air gap and transmitting downward may experience large friction losses against the main side surface 210 defining the air gap. Specifically, the returner 10 is also formed with a positioning end surface abutting against the corresponding end side component, and one end of at least some of the sound insulation members 21 on the sound insulation pattern 2 is flush with the positioning end surface.

[0078] More specifically, Fig.10 , Figure 12 to Figure 13 As shown, the second part 12 is also provided with an ear plate 128, and a positioning hole is provided on the ear plate 128. The embedding groove 34 on the nut 30 has a positioning step. After the reflux return device 10 is assembled into the embedding groove 34, the ear plate 128 abuts against the positioning step, and a coupling hole is provided on the positioning step, and the reflux return device 10 is axially locked by a bolt or a screw passing through the positioning hole and the coupling hole. Preferably, the axial outer end of the ear plate 128 is substantially flush with the above-mentioned positioning end face, and after the reflux return device 10 is assembled into the embedding groove 34, the positioning end face is substantially flush with the bottom surface of the annular groove 33, so as not to occupy the installation space of the end side component 60. Further, the end side component 60 includes a wiper component, and the inner ring of the wiper component is in sealing contact with the raceway groove of the screw 40, so as to reduce the outward propagation of the noise generated in the ball load channel 31 in the axial direction of the screw.

[0079] Embodiment 2

[0080] like Figure 8As shown, the basic structure of this embodiment is the same as that of the first embodiment, and the difference between the two is that the sound insulation pattern 2 in this embodiment is different from that in the first embodiment. Specifically, at least some of the sound insulation components 21 are in the form of columns extending outwards, and the columns extending outwards have at least three main side surfaces, and at least two of the at least three main side surfaces each define the air gap between the main side surface and the main side surface of the adjacent component. Here, most of the columns extending outwards are hexagonal columns with 6 main side surfaces 210, and an air gap with the gas film damping is formed between each main side surface 210 of at least some adjacent columns and the main side surface of the adjacent column, so that the noise and structural resonance transmitted in the return channel 15 can be effectively absorbed.

[0081] In addition, in this embodiment, the outwardly extending column is not arranged in the above-mentioned inwardly concave portion, but is directly extended outwardly from the outward end surface 14, and a surrounding wall is arranged on the periphery of the sound insulation pattern 2 to increase the structural rigidity of the sound insulation pattern 2 directly extending outward, and prevent extrusion deformation during axial assembly, thereby affecting the sound absorption and vibration reduction effect of the sound insulation pattern 2. At least some of the outwardly extending columns adjacent to the surrounding wall may be prisms in other forms, and may have at least two main side surfaces, and at least some of the at least two main side surfaces may define the air gap with gas film damping between the main side surfaces of other prisms or the wall surface of the surrounding wall.

[0082] Embodiment 3

[0083] like Fig. 9 As shown, the basic structure of this embodiment is the same as that of the first embodiment, and the difference between the two is that the sound insulation pattern 2 in this embodiment is different from that in the first embodiment. Specifically, at least one fractal column 232 extending substantially outward from the outward end surface is formed in at least some of the compartments 23, and at least some of the fractal columns 232 are arranged to define the air gap between the main side surface 210 of the adjacent column or between the respective main side surfaces and the corresponding rib wall of the compartment 23. That is, the present embodiment adopts the combination of ribs and columns to form the sound insulation pattern 2. As shown in the figure, most of the fractal columns 232 are generally rectangular parallelepiped-shaped, with four main side surfaces, and at least some of the four main side surfaces can define the air gap with gas film damping between the main side surface of the adjacent column or between the rib wall of the adjacent compartment 23. In some compartments 23 at the edge of the pattern, at least some of the columns can be triangular prism-shaped, quadrangular prism-shaped or other special-shaped column structures, etc., as long as they can form the air gap with the adjacent column or rib.

[0084] In the above-mentioned various embodiments, a sound insulation pattern 2 is directly formed on the outward end surface 14 of the ball screw reflow device 10, and it is ensured that the sound insulation pattern 2 roughly covers the projection area of ​​the curved reflow channel 15 on the outward end surface 14 in the axial direction, and a plurality of air gaps 22 with gas film damping formed in the sound insulation pattern 2 are utilized to absorb the noise and structural resonance generated when the reflow device 10 is working. On the basis of achieving the sound absorption and vibration reduction effects, there is no need to set up additional redundant parts, thereby reducing the processing and manufacturing cost of the screw. At the same time, the sound insulation pattern 2 occupies a small axial installation dimension of the nut, which can leave space for the installation and positioning of the end side components.

[0085] In this specification, the same or similar parts between the various embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the embodiments described later, the description is relatively simple, and the relevant parts can be referred to the partial description of the previous embodiments.

[0086] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A sheathed ball screw returner, mounted on a nut, characterized in that: The returner has: A curved reflux channel for guiding a plurality of balls to perform reflux redirection in the channel; An inward end surface axially abutting against the inner wall of the nut for axially positioning the returner; Outward end surfaces disposed on both sides of the recirculator along the axial direction and separated from the inward end surface; as well as A sound insulation pattern formed on the outward end surface and at least substantially covering the projection area of ​​the curved reflow channel on the outward end surface in the axial direction; The sound insulation pattern includes a plurality of sound insulation members extending generally outward from the outward end surface, and at least some of the plurality of sound insulation members are arranged and spaced to define air gaps with gas film damping between major side surfaces of adjacent members.

2. The ball screw reflow device according to claim 1, characterized in that: The air gap with gas film damping is an air gap having an aspect ratio of at least about 0.3:

1.

3. The ball screw reflow device according to claim 1, characterized in that: The backflow returner is made of an organic polymer material having a density of at least about 0.8 g / cc, and the sound insulation pattern is formed on the outer wall of the backflow returner by molding, printing or etching.

4. The ball screw reflow device according to claim 1, characterized in that: At least some of the sound-damping members are in the form of outwardly extending elongated ribs, at least some of the elongated ribs being arranged and spaced so as to define the air gap between major side surfaces of adjacent ribs.

5. The ball screw reflow device according to claim 1, characterized in that: At least some of the sound insulation components are in the form of outwardly extending slender ribs, the slender ribs including a plurality of longitudinal ribs and transverse ribs, the plurality of longitudinal ribs and transverse ribs dividing a plurality of independent compartments on the outward end surface, the spacing between at least two opposite rib walls of at least some of the compartments being designed so that the frequency of the standing wave that can be generated within the spacing is greater than the frequency of the sound wave generated within the spacing when the return device is in operation.

6. The ball screw reflow device according to claim 5, characterized in that: At least some of the compartments are formed with at least one fractal rib extending generally outwardly from the outward end surface, and at least some of the fractal ribs are arranged to define the air gap between major side surfaces of adjacent ribs or between respective major side surfaces and corresponding compartment rib walls.

7. The ball screw reflow device according to claim 5, characterized in that: At least some of the compartments are formed with at least one fractal column extending generally outwardly from the outward end surface, and at least some of the fractal columns are arranged to define the air gap between the major side surfaces of adjacent columns or between the respective major side surfaces and the corresponding compartment rib walls.

8. The ball screw reflow device according to claim 1, characterized in that: At least some of the sound-deadening members are in the form of outwardly extending posts having at least three major side surfaces, at least two of the at least three major side surfaces each defining the air gap between that major side surface and a major side surface of an adjacent member.

9. A ball screw, characterized in that: include: Screw; A nut surrounding the screw rod, with a ball return passage formed in the axial direction and an embedding groove formed in the axial direction at both ends; A plurality of balls are freely arranged to roll in a ball load channel surrounded by the spiral rolling grooves of the screw and the nut; as well as A pair of returners each embedded in the embedding grooves at both ends of the nut and connected to the ball load channel and the ball return channel to form a ball circulation path; Wherein, the reflux device adopts the ball screw reflux device as described in any one of claims 1 to 8.

10. The ball screw according to claim 9, characterized in that: The reflux device is composed of a first part and a second part which are snap-connected to each other, wherein the first part has a first reflux groove and a tongue portion formed at one end of the first reflux groove, the tongue portion being constructed to extend toward the ball load channel so as to be suitable for picking up the balls from the ball load channel and guiding them into the first reflux groove, and the second part has a second reflux groove, which together with the first reflux groove defines the curved reflux channel.

11. The ball screw according to claim 10, characterized in that: The second reflux groove includes a first cross-sectional segment and a second cross-sectional segment. The first cross-sectional segment is connected to the ball load channel and is constructed as a Gothic tooth profile. The second cross-sectional segment is connected to the ball return channel and is constructed as an arc tooth profile. A smooth transition is adopted between the first cross-sectional segment and the second cross-sectional segment.

12. The ball screw according to claim 9, characterized in that: An annular groove is formed at each end of the nut, and the ball screw also includes an end side component installed in each of the annular grooves. The embedding groove is formed by the bottom surface of each annular groove of the nut being recessed inward along the axial direction, and the return device embedded in the embedding groove abuts between the corresponding embedding groove and the end side component along the axial direction to achieve axial positioning of the return device.

13. The ball screw according to claim 12, characterized in that: The sound insulation pattern on the returner is positioned in a substantially closed space formed between the returner and the end side component.

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