TWI499732B - Manufacturing method for ball screw - Google Patents

Description

Ball screw manufacturing method

The present invention relates to a method of manufacturing a ball screw.

The ball screw is a device widely used in many mechanical devices. The purpose of the ball screw is to provide a precise transmission function. In the mechanical operation, the rotary motion and the linear motion are used to carry the loaded machine or object in a straight line. Actuate.

At present, the ball screw mainly includes a screw, a nut, and a plurality of balls. The surface of the screw has a spiral groove, and the inner surface of the nut also has a spiral inner groove, which can form a ball passage with the screw. The ball is placed therein and formed in a relatively rolling relationship with the screw and the nut to reduce the frictional force between the screw and the nut. Wherein, the ball moves from one end of the ball passage to the other end, that is, after moving from one end of the nut to the other end, it must pass through a reflow device and return to the starting point of the ball passage, so as to continue rolling in the ball passage. .

There are many types of reflowers, but they are generally disposed on the outer surface of the nut body or at the end caps of the nut body. However, in any of the above-described setting positions, in the prior art, in order to form a groove for accommodating the reflow device, the nut body has to undergo a complicated but highly precise processing procedure. However, due to the formation of the groove during the processing of the nut body, the thickness of the meat is often reduced. Therefore, after the heat treatment, the heat deformation amount is often increased due to the thinness of the meat, and the problem of cracking is more likely to occur. Even the structure of the groove portion is distorted, which makes the assembly of the reflow device difficult, so that the ball groove in the reflow device cannot be surely matched with the ball passage, and further affects the smoothness of the circulation motion of the ball.

In short, in the past, in order to maintain the processing accuracy, the above problems were not desired, and the result was an increase in processing difficulty and cost. In addition, there is a problem that the positioning accuracy of the returner provided by the groove after processing is difficult to control.

Therefore, how to provide a method for manufacturing a ball screw can be simplified On the basis of the processing program, the processing difficulty and manufacturing cost are reduced, and the positioning effect and assembly precision of the reflow device on the nut body are enhanced, and a complete stepless ball passage is formed to ensure stable operation of the whole device during application. Has become one of the important topics.

In view of the above problems, an object of the present invention is to provide a method for manufacturing a ball screw, which can reduce the processing difficulty and the manufacturing cost on the basis of a simplified processing procedure, and enhance the positioning effect of the reflow device on the nut body and Assembly accuracy, the formation of a complete stepless ball channel to ensure a stable operation of the overall device in the application.

In order to achieve the above object, a method for manufacturing a ball screw according to the present invention includes the steps of: forming at least one assembly opening on a nut body, wherein the assembly opening extends from one end of the nut body toward the other end surface, And passing through the outer surface and the inner surface of the nut body; assembling a reflow device to the assembly opening; arranging the nut body on a screw, forming a ball passage between the nut body, the return device and the screw; and accommodating the plurality of balls Inside the ball channel.

In an embodiment, the assembly opening is formed by turning or cutting.

In an embodiment, after the assembly opening is formed on the nut body, the method further comprises the step of grinding the inner wall of the assembly opening.

In an embodiment, before the step of assembling the reflow device, the method further comprises the steps of: combining two reflow elements to form a reflow device, and the two reflow elements respectively have a clamping surface and a surface disposed opposite to the clamping surface, the reflow system The contact surface is in contact with the nut body.

In one embodiment, one of the two reflow elements has a latch in the latching mask, and the other of the latching mask has a latching portion, and the two reflowing elements are formed by the latch and the engaging portion being engaged with each other. Return flow.

In an embodiment, after combining the two reflow elements to form a reflow device, the method further comprises the steps of: forming a leak stop structure. One of the two reflow elements has a convex portion on the clamping mask, and the other of the clamping mask has a groove portion, and the convex portion and the groove portion together form a leakage preventing structure when the two reflow elements are engaged with each other.

In one embodiment, the reflow elements have two convex portions on the two sides of the engaging surface, and the other reflow elements have two groove portions on the two sides of the engaging surface.

In an embodiment, the nut body has two sets of oblique sides on two sides of the assembly opening. The extension of the two sets of inclined faces has an angle of intersection, and the returning device is in contact with the two sets of inclined faces of the nut body by the two setting faces.

In one embodiment, the angle of intersection is between 1 and 170 degrees.

In one embodiment, the extension of the two sets of ramps faces the direction of the axis in the nut body.

In one embodiment, the extension of the two sets of ramps is away from the axis of the nut body.

In an embodiment, the manufacturing method further comprises the step of assembling a dustproof component to the assembly opening. The dustproof member has a positioning portion, and the positioning portion is fixed in the assembly opening.

As described above, in the method of manufacturing the ball screw according to the present invention, the assembly opening through the outer surface and the inner surface of the nut body is formed on the nut body for the reflow device. In particular, the assembly opening extends not only through the body and the outside of the nut body, but also extends from one end of the nut body toward the other end surface, so that the assembly opening presents an open opening structure with respect to the nut body, and is suitable for use in an open type. The processing method is made. Open processing methods, such as turning and milling, are relatively easy and easy to manage.

Compared with the conventional method of forming a non-penetrating groove structure on the outer surface or the end surface of the nut body, the present invention does not need to additionally consider whether the thickness of the nut body is sufficient, and the meat thickness is not caused by processing. After the heat treatment, the heat deformation amount is large and the chip is easily broken. Moreover, the processing method of the present invention is also less prone to distortion at the assembly opening, which affects subsequent assembly accuracy.

Overall, the manufacturing method of the present invention can be completed through a simple processing process, which not only greatly reduces the difficulty and time consuming of processing, but also further improves the manufacturing precision and yield to improve the stability of the ball screw as a whole.

1, 1'‧‧‧ screw

11‧‧‧ Track slot

2‧‧‧ nuts

21, 21’‧‧‧ nut body

211‧‧‧inside ball groove

212, 213‧‧‧ Assembly opening

214‧‧‧Reflux channel

215, 215', 216, 216' ‧ ‧ set of inclined faces

22, 22'‧‧‧ reflux

221‧‧‧First reflow element

221a‧‧‧ first card junction

221b‧‧‧First setting surface

221c‧‧‧Care Department

221d‧‧‧ slot

222‧‧‧Second reflow element

222a‧‧‧Second card junction

222b‧‧‧Second setting surface

222c‧‧‧Carmen

222d‧‧‧ convex

223‧‧‧Return holes

224‧‧‧ gap

23‧‧‧ screws

24‧‧‧Dustproof components

241‧‧‧ Positioning Department

242‧‧ ‧Tongue

243‧‧‧ inner edge

3, 3'‧‧‧ balls

A-A‧‧‧ hatching

CP‧‧‧ cycle

ES1‧‧‧ first end face

ES2‧‧‧ second end

IS‧‧‧ inner surface

L‧‧‧ leak-proof structure

OS‧‧‧ outer surface

S‧‧‧Rolling screw

θ‧‧‧Corrugated angle

S11~S17‧‧‧Steps

1 is a flow chart showing the steps of a method of manufacturing a ball screw according to an embodiment of the present invention.

2A is a schematic view showing the appearance of a ball screw obtained by the process shown in FIG. 1.

2B is an exploded perspective view of the ball screw shown in FIG. 2A.

Figure 2C is a perspective view of the ball screw of Figure 2A.

2D is a schematic view showing the combination of the ball screw returning device shown in FIG. 2C.

2E is a schematic cross-sectional view of the ball screw shown in FIG. 2A at a section line A-A.

3 is a cross-sectional view showing a ball screw according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method of manufacturing a ball screw according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings, wherein the same elements will be described with the same reference numerals.

1 is a flow chart showing the steps of a method for manufacturing a ball screw according to an embodiment of the present invention. FIG. 2A is a schematic view showing the appearance of a ball screw obtained by the process shown in FIG. 1, and FIG. 2B is a view showing a ball screw shown in FIG. Decomposition diagram. Referring to FIG. 1 , FIG. 2A and FIG. 2B simultaneously, the ball screw S is composed of a plurality of components, and the components mainly include a screw 1 , a nut 2 , and a plurality of balls 3 . The nut 2 is slidably disposed on the screw 1, and the nut 2 and the screw 1 together form a ball passage, and the ball 3 is accommodated in the ball passage. The method for manufacturing a ball screw of the embodiment may include the following steps: forming at least one assembly opening on a nut body, wherein the assembly opening extends from one end of the nut body toward the other end surface, and the through screw The outer surface and the inner surface of the cap body (S11); a reflow device is assembled to the assembly opening (S13); the nut body is sleeved on a screw, and a ball passage is formed between the nut body, the reflow device and the screw (S15); A plurality of balls are accommodated in the ball passage (S17).

In the description of each step, please refer to the appearance and the exploded view of the ball screw shown in FIG. 2A and FIG. 2B in order to understand the technical content of the present invention. Before the step S11 of the present invention is implemented, a nut body (not shown) is first processed to form a nut body 21. Specifically, the nut body material may be a metal block or a columnar material, and after being ground, the nut body 21 and its detailed structure are formed. Of course, the processing method of the nut body 21 is not limited. In practical applications, the nut body 21 can also be made by other methods such as casting, forging, and milling. The nut body 21 can be an annular cylinder and an inner ball groove 211 is formed on the inner side. Of course, in the actual manufacturing process, the flange hole, the oil hole, the return hole and the like may be drilled on the nut body according to the use requirement, or even the surface heat treatment of the nut body may be performed to strengthen the hardness of the nut body. The invention is not limited thereto.

In this embodiment, before the step S11, the screw body 21 may be correspondingly formed, and a screw 1 is formed. The screw 1 is a cylindrical rod body, and the outer surface has a corresponding inner ball. A groove 211 and a spiral track groove 11 continuously wound along the longitudinal axis. By the corresponding arrangement of the track groove 11 and the inner ball groove 211, when the nut body 21 and the screw 1 are assembled, the two together form a ball passage.

In the step S11, at least one assembly opening is formed on the nut body. In particular, the assembly opening is used for a reflow device, and the implementation details will be described in the following paragraph. Referring to FIG. 2B , the present embodiment is exemplified by forming two assembly openings 212 , 213 , and the two assembly openings 212 , 213 are disposed on opposite sides of the nut body 21 . In detail, the two assembly openings 212 and 213 extend from one end of the nut body 21 toward the other end surface, and the assembly opening 212 is taken as an example, which is from the first end surface ES1 of the nut body 21 to the second end surface. The direction of the ES2 extends. At the same time, the assembly opening 212 also penetrates the outer surface OS and the inner surface IS of the nut body 21, thereby presenting an "open" gap form with respect to the nut body 21. Therefore, in the process, the embodiment only needs to be through the lathe milling method, in particular, the CNC turning and milling method, that is, the open working manner can be adopted on the nut body 21, for example, from the first end face ES1 or from the outer surface. From the OS, the former is directed to the second end face ES2, and the latter is directed to the inner surface IS to directly cut the block of a predetermined size to form the assembly opening 212. In practical applications, the assembly opening can also be formed by turning or cutting. In addition, the nut body 21 defines that the side wall of the assembly opening 212 can be further processed by grinding and/or polishing to remove the remaining burrs after the rough molding, which helps to reduce the tolerance, and the present invention is not limited thereto. Further, other operational portions not described above should be understood by those having ordinary skill in the art to which the present invention pertains, and will not be described herein.

In addition, it is particularly worth mentioning that since the open processing is performed and the openings are formed through the inside and the outside, when the quality control is performed, there is an advantage that the detection is easy and the measuring tool is simplified.

In view of the above, the nut body 21 and the assembly openings 212 and 213 formed by the manufacturing method of the present invention can be formed by an open processing method, which not only greatly reduces the difficulty and time consuming of the small structure processing, but also It is advantageous to improve the precision of assembling the openings 212, 213.

2C is a perspective view of the ball screw returning device shown in FIG. 2A. Please refer to FIG. 1 to FIG. 2C at the same time. Before the step S13 is explained, the flow head is first described. The reflow device according to the present invention may be of a single structure or a combination of multiple components as shown in Fig. 2C. When the reflow device is a single structure, the process is relatively simple, and the combined structure of the multi-components has the problem of improving the accuracy and reducing the difficulty of internally processing the ball passage.

In this embodiment, the reflow device 22 is formed by combining two reflow elements as an example. In order to clarify the detailed structure and combination of the two reflow elements, a first reflow element 221 and a second reflow element 222 are respectively referred to, but the two are not the same or different.

The first reflow element 221 has a first engaging surface 221a and a first mounting surface 221b opposite to the first engaging surface 221a. Conversely, the second reflow element 222 has a second engaging surface 222a and opposite to the first One of the second engaging faces 222a is a second setting face 222b. The term "card joint" is a surface that abuts each other when the reflow elements are combined; the so-called installation surface is a surface that abuts the nut body when the reflow element is assembled with the nut body.

In the embodiment, the first engaging surface 221a has two engaging portions 221c, and the second engaging surface 222a has two latches 222c corresponding to the two engaging portions 221c. The above-described cassette 222c and the engaging portion 221c are engaged with each other to form the above-described reflux unit 22. On the other hand, through the combination of the first reflow element 221 and the second reflow element 222, a reflow hole 223 can be defined, and the return hole 223, the return passage 214 on the nut body 21, and the aforementioned ball passage are closely connected to each other to form a Ball circulation path.

Of course, in other embodiments, the position of the cassette and the engaging portion may be interchanged, or other engaging or fixing structures may be additionally disposed on the two reflow elements, and the shape and the position of the engaging portion and the engaging portion are The quantities are not limited by the invention.

2D is a schematic view showing the combination of the ball screw returning device shown in FIG. 2C. Referring to FIG. 2C and FIG. 2D, after the first reflow element 221 and the second reflow element 222 are combined to form the reflow device 22, the two reflow elements are simultaneously A leak stop structure L can be formed together. In detail, the first reflow element 221 has a groove portion 221d on the first engaging surface 221a, and the second reflow element 222 has a convex portion 222d on the second engaging surface 222a, and the shape and arrangement position of the convex portion 222d. Produces an effect similar to an eaves. The convex portion 222d and the groove portion 221d together form a leakage preventing structure L when the first and second reflow elements 221 and 222 are engaged with each other. The convex portion 222d and the groove portion 221d referred to in the present embodiment are specifically referred to as "oil retaining convex portion" and "oil retaining groove portion". Specifically, the convex portion 222d and the groove portion 221d are disposed so as to surround the returning device 22. A part of the ball circulation path CP, when the lubricating oil oozes out from the partial ball circulation path CP, it is not easy to pass through the leakage preventing structure L formed by the convex portion 222d and the groove portion 221d and having at least two bending. The surface of the reflow device 22 is oozing out, in other words, by the appearance of the reflow device 22 (as shown in FIG. 2D), the slit 224 formed by the first engaging surface 221a and the second engaging surface 222a is not straight. Shape, and the system presents a labyrinth configuration (with a second bend). Therefore, through the design of the leak-stop structure L, the return device 22 can be prevented The lubricating oil added to the return hole 223, the return passage 214, and the ball passage is oozing out from the gap 224 between the first and second return members 221, 222, and more preferably, the combined return device 22 is prevented from being subjected to an external force or Oil leakage problems caused by deformation problems caused by heat treatment.

In particular, the first reflow element 221 of the embodiment is provided with two groove portions 221d on the two sides of the first engagement surface 221a, and two convex portions on the two groove portions 221d of the second reflow element 222. The portion 222d can further provide the effect of preventing leakage and preventing leakage on the two leaking devices 22, but in actual application, the position of the groove portion 221d and the convex portion 222d can be interchanged, or Further, the other leakage preventing structures L are additionally provided on the first and second reflow elements 221 and 222. Further, the shapes, arrangement positions and the number of the groove portions 221d and the convex portions 222d are not limited by the present invention.

2E is a schematic cross-sectional view of the ball screw shown in FIG. 2A at a section line A-A. Referring to FIG. 2B and FIG. 2E , in the embodiment, the nut body 21 has two sets of inclined surfaces 215 and 216 on two sides of the assembly openings 212 and 213 , and the return flow device 22 is the second of the two reflow elements. 1. The second setting surfaces 221b and 222b are respectively in contact with the two sets of inclined surfaces 215 and 216 of the nut body 21. Of course, the first and second setting surfaces 221b and 222b have corresponding to the two sets of inclined surfaces 215 and 216. Slope.

From the above, as shown in FIG. 2E, the extension of the two sets of inclined faces 215, 216 has an angle of intersection θ. Of course, the "extension" referred to herein is a virtual extension. Wherein, the angle of the intersection angle θ can be between 1 and 170 degrees. Through the design of the slope, the backflow device 22 can be effectively prevented from being displaced in the direction of the screw 1, and the limit effect is produced. In the present embodiment, the extension of the so-called combination bevels 215, 216 refers to the direction of the axis of the nut body 21, in particular, the "direction of the central axis" of the nut body 21 referred to herein. It refers to the direction parallel to the long axis of the screw 1. Specifically, the two sets of inclined faces 215 and 216 of the present embodiment exhibit an outwardly expanded shape with respect to the screw 1 , and have the advantages of improved assembly and positioning ease when the return flow device 22 is combined.

In addition, in the embodiment, the reflow device 22 is screwed to the nut body 21 by screws 23 respectively. For this reason, in the practical application, the reflow device 22 can also be engaged and bonded. , the locking, the fitting or a combination thereof is fixed to the nut body 21, even at the contact position of the returning device 22 and the nut body 21, the adhesive is adhered by the outer side of the first end surface ES1 or the second end surface ES2, This is not limited.

Further, in the present embodiment, the ball screw has two dustproof members 24. dust-proof The component 24 further has a positioning portion 241. When the dustproof member 24 is assembled with the nut body 21, the two positioning portions 241 are respectively fixed in the assembly openings 212, 213. Compared with the conventional combination of the dustproof components, the present invention eliminates the extra step of screw locking by the cooperation of the combination inclined faces 215, 216 and the positioning portion 241 of the dustproof member 24, simplifies the dustproof member 24 and the nut body 21. More preferably, since the positioning portion 241 is fixed in the assembly openings 212, 213 and cannot be rotated, the effect of restricting the rotation of the dustproof member 24 is provided, and the dustproof member 24 is provided to the nut body 21 to provide a better dustproof effect.

In addition, the dustproof member 24 further has a tongue portion 242, and the tongue portion 242 is disposed on a portion of the inner edge 243 of the dustproof member 24. In detail, the tongue portion 242 is defined by the inner edge 243 extending continuously toward the center of the dustproof member 24, and the extended shape is a tongue shape or a half moon shape, so that the tongue portion 242 can be referred to. However, the present invention is not limited to the above-described shape, and in practical applications, even if the shape is not completely similar to the tongue shape or the half moon shape, it is within the scope of the present invention.

Through the assembly of step S13, a nut 2 structure is formed. In step S15 and step S17, the nut body 21 can be sleeved on the screw 1, and a ball passage is formed between the nut body 21, the reflow device 22 and the screw 1, and the plurality of balls are formed. The ball 3 is housed in the ball passage. However, the actual operation and application mode of the ball screw S can be understood by those having ordinary knowledge in the field of the invention, and details are not described herein.

3 is a cross-sectional view of a ball screw according to another embodiment of the present invention. Referring to FIG. 3, in the present embodiment, the nut body 21' of the ball screw and the recirculator 22' are the same as the foregoing embodiment. With the same majority of features, the extension of the two sets of inclined faces 215', 216' is away from the axis of the nut body 21'. Specifically, the second set of inclined faces 215', 216' of the present embodiment is relative to the screw. 1' presents a concave shape and additionally provides better dust protection.

In summary, according to the method for manufacturing a ball screw of the present invention, an assembly opening penetrating the outer surface and the inner surface of the nut body is formed on the nut body for the reflow device. In particular, the assembly opening extends not only through the body and the outside of the nut body, but also extends from one end of the nut body toward the other end surface, so that the assembly opening presents an open opening structure with respect to the nut body, and is suitable for use in an open type. The processing method is made. Open processing methods, such as turning and milling, are relatively easy and easy to manage.

Compared with the conventional surface, the non-through type is formed only on the outer surface or the end surface of the nut body. In terms of the groove structure, the present invention does not need to additionally consider whether the thickness of the nut body is sufficient, and the thickness of the meat is not thinned by processing, and after heat treatment, the problem of large thermal deformation and easy chipping is easily generated. Moreover, the processing method of the present invention is also less prone to distortion at the assembly opening, which affects subsequent assembly accuracy.

Overall, the manufacturing method of the present invention can be completed through a simple processing process, which not only greatly reduces the difficulty and time consuming of processing, but also further improves the manufacturing precision and yield to improve the stability of the ball screw as a whole.

The above is intended to be illustrative only and not limiting. Any equivalent modifications or alterations to the spirit and scope of the invention are intended to be included in the scope of the appended claims.

S11~S17‧‧‧Steps

Claims (10)

A method for manufacturing a ball screw includes the steps of: forming at least one assembly opening on a nut body, wherein the assembly opening extends from one end of the nut body toward the other end surface and penetrates the nut body The outer surface and the inner surface; the combined two reflow elements form a reflow device, and the two reflow elements respectively have a clamping surface and a surface disposed opposite to the clamping surface, the reflow device adopting the two setting surfaces and the screw Contacting the cap body; forming a leak stop structure, wherein one of the two reflow elements has a convex portion on the snap mask, and the other of the snap mask has a groove portion, and the convex portion and the groove portion are When the two reflow elements are engaged with each other, the leakage prevention structure is formed; the reflow device is assembled to the assembly opening; the nut body is sleeved to a screw, and a ball is formed between the nut body and the reflow device and the screw a channel; and accommodating a plurality of balls in the ball passage. The manufacturing method of claim 1, wherein the assembly opening is formed by turning or cutting. The manufacturing method of claim 1, wherein after forming the assembly opening on the nut body, the method further comprises the step of grinding the inner wall of the assembly opening. The manufacturing method of claim 1, wherein one of the two reflow elements has a latch in the snap mask, and the other of the snap mask has a latch, and the two reflow elements The reflow device is formed by the card and the engaging portion being engaged with each other. The manufacturing method of claim 1, wherein the reflow element has two convex portions on two sides of the engaging surface, and the other reflowing member has a side on each of the engaging surfaces. Two of the groove parts. The manufacturing method of claim 1, wherein the nut body has two sets of inclined faces on two sides of the assembly opening, the two sets of inclined slopes have an intersecting angle, and the returning device is configured by the two The setting surface is in contact with the two sets of inclined faces of the nut body. The manufacturing method according to claim 6, wherein the angle of the intersection angle is between 1 and 170 degrees. The manufacturing method of claim 6, wherein the extension of the two sets of inclined faces faces the direction of the axis of the nut body. The manufacturing method of claim 6, wherein the extension of the two sets of inclined faces is away from the axis of the nut body. The manufacturing method of claim 1, further comprising the step of assembling a dustproof member to the assembly opening, the dustproof member having a positioning portion, and the positioning portion is fixed in the assembly opening.