CN103244628A - Tangential external circulation ball screw - Google Patents

Abstract

The invention discloses a tangent external circulation type ball screw, comprising: a screw; a nut, it is equipped with a through-hole that supplies this screw rod to wear to establish, is equipped with a plurality of mounting holes that communicate with this through-hole in the surface of this nut, and this mounting hole contains: a first containing hole and a second containing hole; the first containing hole is communicated with the second containing hole, the width of the first containing hole is larger than that of the second containing hole, the depth of the first containing hole is smaller than that of the second containing hole, and the limited space of the screw cap is effectively applied by means of the different pore sizes of the first containing hole and the second containing hole; the installation hole is designed in multiple stages, so that the installation hole cannot interfere with the rolling groove.

Description

Tangential external circulation ball screw

technical field

The invention relates to a linear transmission element, in particular to a tangential external circulation ball screw.

Background technique

Please refer to Fig. 1 to Fig. 5, which are conventionally used tangential external circulation type ball screw, the tangential external circulation type ball screw includes: a screw 4, the outer edge surface of which is provided with a spiral rolling groove 41, A nut 1 is provided with a through hole 11 for the screw rod 4 to pass through. The inner edge of the through hole 11 is provided with a rolling groove 111 opposite to the rolling groove 41. The rolling groove 41 and the rolling groove 111 form a load Path, the outer surface of the nut 1 is provided with a plurality of installation holes 12 communicating with the through hole 11, and a plurality of screw holes 13, the installation holes 12 are connected with the rolling groove 111, and adjacent to the joint There is a bearing surface 121; at least one return element 2, the return element 2 is ㄇ-shaped, the two ends of the ㄇ-shape are defined as the foot A, and the connection between the two feet A is defined as the connecting portion B, the two feet Parts A are respectively inserted into the mounting holes 12, and the connecting part B is arranged on the outer edge surface of the nut 1. The return element 2 is provided with a return channel 23, and the return channel 23 runs through the two legs A and the connecting part. B, and the two ends of the return channel 23 are connected to the load path and are designed as a tangential return path, and it can be known from Figures 1 and 2 that the return element is composed of two components 22, 21, which are divided into two parts. The one-piece type is mainly convenient to manufacture. The two components 22, 21 are respectively provided with half return channels 222, 211, and the two half return channels 222, 211 form the return channel 23. In addition, the return element 2 is provided with a perforation corresponding to the screw hole 13. 221 , after a plurality of screws 3 pass through the through hole 221 , the screw 3 is screwed and locked with the screw hole 13 , so that the return element 2 is fixed on the nut 1 .

However, the structural design of this kind of tangential external circulation ball screw is not suitable for the load path with low lead (composed of rolling groove 41 and rolling groove 111), [Note: The so-called low lead means the distance between the load paths Small, in other words, the axial X thickness of the portion between adjacent rolling grooves 41 or rolling grooves 111 (commonly known in the industry as tooth crest) is small, while the axial X thickness of the low-lead tooth crest will be smaller. Smaller than the axial X thickness of the high-lead tooth crest], because the mounting hole 12 is currently designed as an elliptical hole, which will interfere with the rolling groove 111 after processing (see Figure 2 and Figure 3), so that the The two sides of the rolling groove 111 connected by the installation hole 12 are damaged R, which is commonly known as a broken tooth in the industry, making the nut 1 unusable and must be scrapped. Therefore, if a customer wants to purchase a low-lead tangential external circulation ball screw, he will suggest that the customer choose other circulation methods (such as: internal circulation, etc.), but because the tangential external circulation has the advantages that the internal circulation cannot achieve. The advantage of the non-impact return path can reduce the running noise of the ball screw and allow the operating speed to be greatly increased compared with the internal circulation. Therefore, some customers choose the tangential external circulation ball screw because of its advantages. Therefore, how to make the tangential external circulation The recirculating ball screw is applied to low-lead specifications, which is the focus of active improvement and development in the industry.

In view of this, the inventor of the present invention aimed at many shortcomings and inconveniences caused by the imperfect structure design of the above-mentioned tangential external circulation type ball screw, and deeply conceived, and actively researched and improved the trial production to develop and design the present case.

Contents of the invention

The purpose of the present invention is to provide a low-lead tangential external circulation ball screw, so that the installation hole does not interfere with the rolling groove, so as to achieve the purpose of applying the tangential external circulation ball screw to the specification of low lead.

In order to achieve the above object, the solution of the present invention is:

A tangential external circulation ball screw, comprising:

A screw, the outer surface of which is provided with a spiral rolling groove;

A nut, which is provided with a through hole for the screw to pass through. The inner edge of the through hole is provided with a rolling groove opposite to the rolling groove. The rolling groove and the rolling groove form a load path. The surface is provided with a plurality of installation holes communicating with the through hole;

A return element, the return element is provided with two legs, the two legs are connected by a connecting part, the two legs are respectively inserted in the installation hole, and the connecting part is arranged on the outer edge surface of the nut , the return element is provided with a return channel, the return channel passes through the two legs and the connecting part, and the two ends of the return channel are connected to the load path;

The installation hole includes: a first cavity and a second cavity; the first cavity and the second cavity are connected, the width of the first cavity is greater than the width of the second cavity, and the depth of the first cavity less than the depth of the second well.

The above-mentioned two legs are respectively constituted by a first stage portion relatively accommodated in the first cavity, and a second stage portion accommodated in the second cavity.

The outer profile of the first stage portion is set relative to the inner profile of the first cavity, and the outer profile of the second stage portion is set relative to the inner profile of the second cavity.

The above-mentioned return element is composed of a first component and a second component. The first component and the second component are respectively provided with half of the return channel, and the two halves of the return channel form the return channel, and the first stage and the second stage are arranged on the first component.

The above-mentioned first cavity is provided with at least one abutting surface, the first member is provided with a first abutting surface opposite to the abutting surface, and the first step is provided with a second abutting surface opposite to the abutting surface , the first abutting surface and the second abutting surface connect to each other to form an abutting surface, and the abutting surface abuts against the abutting surface.

The above-mentioned first member is provided with two legs.

After adopting the above structure, the feet of the return element of the tangential external circulation ball screw of the present invention are set as the first stage and the second stage, so the width of the first cavity is designed to be larger than the width of the second cavity, and the second cavity is designed to be wider than the second cavity. The depth of the first cavity is smaller than the depth of the second cavity, and the installation hole is designed in a multi-level manner (this embodiment is two levels, but it can also be designed as more than two levels of installation holes due to space constraints) and The first stage and the second stage of the foot of the return element cooperate to prevent the installation hole from interfering with the rolling groove, so as to achieve the purpose of applying the tangential external circulation ball screw to the specification of low lead. When processing the mounting hole, only two end mills with different diameters can be used to complete the processing. The larger diameter end mill is used to process the first cavity, and the smaller diameter is used to process the second. Pore. 

Description of drawings

FIG. 1 is an exploded view of a tangential external circulation ball screw in the prior art;

Fig. 2 is another perspective exploded view of the tangential external circulation ball screw of the prior art;

Fig. 3 is a combination diagram of a tangential external circulation ball screw in the prior art;

Fig. 3 A is the enlarged view of I place in Fig. 3;

Fig. 4 is the sectional view of the radial direction cut-off of the nut of prior art, is to see it with top view;

Fig. 5 is a cross-sectional view in which the reflux element of the prior art is combined with a nut and cut in the radial direction, and is viewed from a top view;

Fig. 6 is an exploded view of the tangential external circulation ball screw of the present invention;

Fig. 7 is another perspective exploded view of the tangential external circulation ball screw of the present invention;

Figure 8 is a combination diagram of the tangential external circulation ball screw of the present invention;

Fig. 9 is a cross-sectional view of the radial direction of the nut of the present invention, viewed from the top view, mainly showing that the depths of the first cavity and the second cavity are different;

Fig. 10 is a sectional view of the reflux element of the present invention combined with a nut and cut in the radial direction, viewed from the top view;

Fig. 11 is a cross-sectional view of the return element combined with the nut of the present invention and cut in the radial direction, viewed from the top view, mainly showing the cooperation between the abutment surface of the mounting hole and the abutment surface of the return element;

Figure 11A is an enlarged view at J in Figure 11;

Fig. 12 is an axial sectional view of the nut of the present invention, mainly showing the cooperation between the abutment surface of the mounting hole and the abutment surface of the return element;

FIG. 12A is an enlarged view at K in FIG. 12 .

Description of main component symbols

Known technology

1 nut 11 through hole 111 rolling groove

12 Mounting holes 121 Bearing surface 13 Screw holes

2 return element 22, 21 member 221 perforation

222, 211 half return channel 3 screws

4 screws 41 rolling groove A foot

B connection part R damage X-axis direction

this invention

1 nut 11 through hole 111 rolling groove

12 Mounting hole 121 First hole 122 Second hole

123 bearing surface 13 screw hole 2 return element

22 The first component 211 Half return channel 212 The first abutment surface

21 second component 221 perforation 222 first class

223 second stage part 224 second abutment surface 225 half return channel

23 return channel 24 guide part 3 screws

4 screw 41 rolling groove H, h depth

D, d width X-axis direction A foot

B connection part Y abutment surface.

Detailed ways

In order to further explain the technical solution of the present invention, the present invention will be described in detail below through specific examples.

Please refer to Figures 6 to 12, which are a preferred embodiment of the present invention. The present invention is a tangential external circulation ball screw, including:

A screw 4, the outer surface of which is provided with a spiral rolling groove 41;

A nut 1 is provided with a through hole 11 for the screw rod 4 to pass through. The inner edge of the through hole 11 is provided with a rolling groove 111 opposite to the rolling groove 41. The rolling groove 41 and the rolling groove 111 form a load path, the load path accommodates a plurality of rolling elements (not shown), and the outer surface of the nut 1 is provided with a plurality of mounting holes 12 communicating with the through hole 11, and a plurality of screw holes 13, the mounting holes 12 Including: a first cavity 121 and a second cavity 122; the first cavity 121 and the second cavity 122 are connected, the width D of the first cavity 121 is greater than the width d of the second cavity 122, and the first cavity 121 is connected to the second cavity 122. The depth H of a container hole 121 is smaller than the depth h of the second container hole 122, as shown in Figure 6 and Figure 9; face 123;

A return element 2, the return element 2 is provided with two legs A, and the two legs A are connected by a connecting part B, the two legs A are respectively inserted in the installation holes 12, and the two legs A are respectively connected by Compared with the first step part 222 accommodated in the first cavity 121 and the second step part 223 accommodated in the second cavity 122, the outline of the first step part 222 is opposite to that of this embodiment. The inner contour of the first receiving hole 121 is set, and the outer contour of the second step part 223 is set relative to the inner contour of the second receiving hole 122 in this embodiment, so that the first step part 222 and the first receiving hole 121 and the second step part 223 and the second cavity 122 to prevent foreign matter dust from entering the through hole; and the return element 2 of this embodiment is composed of the first member 22 and the second member 21, which are divided into The two-piece type is mainly for the convenience of manufacture. The first component 22 and the second component 21 are respectively provided with half return channels 225, 211, and the two half return channels 225, 211 form a return channel 23, and the return channel 23 runs through the two legs A and connecting portion B, and the two ends of the return channel 23 are connected with the load path along the tangential direction of the load path, and the return element 2 is respectively provided with a guide part 24 at both ends of the return channel 23, the guide The part 24 protrudes toward the rolling groove and is accommodated in the rolling groove to guide a plurality of rolling elements to enter the return channel 23. The second member 21 is provided with a first abutment against the abutment surface 123 surface 212, the first step portion 222 is provided with a second abutment surface 224 opposite to the abutment surface 123, and the first abutment surface 212 and the second abutment surface 224 are joined together to form an abutment surface in this embodiment Y, and the abutment surface Y abuts against the abutment surface 123, and by the contact between the abutment surface 123 and the abutment surface Y (see Fig. 11 and Fig. 12), the two feet A can be more It is stably arranged in the mounting hole 12, and the connecting portion B is arranged on the outer surface of the nut 1; in addition, the return element 2 is provided with a perforation 221 opposite to the screw hole 13, and the perforation 221 is used for a plurality of screws. 3 After piercing, the screw 3 is screwed and locked with the screw hole 13, so that the return element 2 is fixed on the nut 1; The second stage portion 223 is disposed on the first member 22 .

The structure and mutual configuration of each element are described above, and the design principle and the achieved effect of the nut and the return element of the present invention are explained below:

Please refer to Fig. 6 to Fig. 12, the currently used mounting holes are designed to have the same diameter, so the mounting holes and rolling grooves will interfere; and the foot A of the return element 2 of the present invention is set as the first stage portion 222 and the second step portion 223, so the width D of the first cavity 121 is designed to be greater than the width d of the second cavity 122, and the depth H of the first cavity 121 is smaller than the depth h of the second cavity 122, by The installation hole 12 has a multi-stage design (two stages in this embodiment, but it can also be designed as more than two stages of installation holes due to space constraints) and the first stage portion 222 and the first stage portion 222 of the foot A of the return element 2. The second step portion 223 cooperates so that the installation hole 12 does not interfere with the rolling groove 11 , so as to achieve the purpose of applying the tangential external circulation type ball screw to the specification of low lead. When processing the mounting hole 12, only two kinds of end mills with different diameters can be used to complete the processing, the larger diameter end mill is used to process the first receiving hole 121, and the smaller diameter is used to process The second cavity 122 .

The above-mentioned embodiments and drawings do not limit the form and style of the product of the present invention, and any appropriate changes or modifications made by those skilled in the art should be considered as not departing from the patent scope of the present invention.

Claims (6)

1. A tangential external circulation ball screw, comprising: A screw, the outer surface of which is provided with a spiral rolling groove; A nut, which is provided with a through hole for the screw to pass through. The inner edge of the through hole is provided with a rolling groove opposite to the rolling groove. The rolling groove and the rolling groove form a load path. The surface is provided with a plurality of installation holes communicating with the through hole; A return element, the return element is provided with two legs, the two legs are connected by a connecting part, the two legs are respectively inserted in the installation hole, and the connecting part is arranged on the outer edge surface of the nut , the return element is provided with a return channel, the return channel passes through the two legs and the connecting part, and the two ends of the return channel are connected to the load path; It is characterized in that: the installation hole includes: a first cavity and a second cavity; the first cavity and the second cavity are connected, the width of the first cavity is greater than the width of the second cavity, the first cavity The depth of the cavity is smaller than that of the second cavity. 2. The tangential external circulation type ball screw according to claim 1, wherein the two legs are respectively composed of a first step portion relatively accommodated in the first cavity and a step portion accommodated in the second cavity. Formed by the second class department. 3. The tangential external circulation ball screw according to claim 2, characterized in that: the outer contour of the first stage is set relative to the inner contour of the first cavity, and the outer contour of the second stage is opposite to The inner contour of the second cavity is set. 4. The tangential external circulation ball screw according to claim 2, characterized in that: the return element is composed of a first component and a second component, and the first component and the second component are respectively provided with half of the return channel, and the two halves of the return flow channel The channel constitutes a return channel, and the first stage and the second stage are arranged on the first component. 5 . The tangential external circulation ball screw according to claim 4 , wherein the first cavity is provided with at least one abutment surface, and the first member is provided with a first abutment against the abutment surface. surface, the first step portion is provided with a second abutment surface opposite to the abutment surface, the first abutment surface and the second abutment surface are joined together to form an abutment surface, and the abutment surface abuts against the abutment surface Bearing face. 6 . The tangential external circulation ball screw according to claim 4 , wherein the first member is provided with two legs. 7 .

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