JP2008039050A - Roller screw system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a roller screw system that increases the flowability of overall recirculation to reduce the volume of a nut. <P>SOLUTION: The roller screw system comprises a screw, a nut, paired recirculation elements, a recirculation pipe and a roller. A through hole that connects to a recirculation hole is cut in the nut. The recirculation pipe is passed into the through hole in the nut, whereby the recirculation elements are mounted in storage grooves on the nut to form a recirculation system. The screw is connected to a helical rail on the nut to provide a complete roller screw system. Thus it is possible to simultaneously solve two major problems, i.e., reduced ease of rotation due to an excessively small radius of curvature of a recirculation path, and an increase in the volume of the nut due to the installation of a curved pipe. Also, the ease of overall recirculation is increased and the purpose of reducing the volume of the nut is attained. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is a roller screw system, and particularly refers to a locking localization structure that relatively creates a reflux element and a reflux pipe, and can be applied to a roller screw to improve the overall reflux smoothness, and the volume of the nut The purpose can be reduced.

  Roller screws are now being widely applied on the industrial side, but in addition to providing high precision effects as linear feed transmission, they also have low frictional wear rate, high energy conversion rate, low noise and high rigidity. Needless to say, the roller screw is actually important for each industrial application machine because it has the advantage that it is difficult to damage.

  The conventional roller screw design requires that the roller between the screw and the nut be continuously circulated and that the stress be relieved, both need to be fitted with a return element corresponding to the screw thread and roller at both ends of the nut. There is. The reflux element is a key point for refluxing mainly after the roller inside the roller screw is operated between the screw and the nut. Therefore, it can be understood how research and development on the reflux device is important for the industry to improve more competitive products.

  Conventionally, commonly used or recognized reflux circulation molds are divided into two types, and the conventional roller screw is mainly composed of a screw, a nut and a roller, as will be described below. is there.

  First, the roller circulation method often used includes an internal circulation method and an external circulation method.

  In the internal circulation system, each ring constitutes one circulation, so that a small resistance force or wear can be obtained. However, when it is necessary to receive a larger load, it is necessary to adopt a roller screw that is an external circulation method. In the external circulation method, a curved tube that guides the reflux of the ball is installed on the outer peripheral surface of the nut. Will be. However, when the nut size is large, the nut is small, and a large load is applied, an internal circulation type ball screw must be adopted.

  Referring to the drawing of US Pat. No. 3,192,791 shown in FIG. 1, the conventional technique disclosed in FIG. 1 includes an external circulation type roller screw and will be described from both sides by a combination structure according to the drawing.

  A curved tube for guiding the reflux of the roller 10 is provided on the outer peripheral surface of the nut 7, and the curved tube 8 has a rectangular cross section 9.

  Even if such a conventional product is put to practical use, some problems remain, and it is still necessary to research and develop and to improve it.

  On the other hand, in the above prior art, since the bending tube 8 itself has to bend and plastically deform, there is a certain degree of difficulty in manufacturing, and the roller is refluxed on the outer peripheral surface of the nut. Since the curved tube to be guided is installed, the external dimension of the nut is necessarily increased.

Secondly, in the case of such a conventional technique, when the bending curve of the bending tube 8 having a larger roller 10 or the number of reflux of the roller 10 is large, the smoothness of the reflux may be deteriorated. When entering the reflux system from the nut, because of the design of the curved path, the roller 10 first collides with the turning portion of the curved tube 8 and enters the reflux system, so the reflux path of all the rollers 10 becomes discontinuous, There are two major problems that need to be made to increase the reflux smoothness or the volume of the nut.
US Pat. No. 3,192,791

  It is an object of the present invention to mainly provide a roller screw system, to improve the flow rate of the entire reflux, and to reduce the volume of the nut.

  In order to achieve the above object, the present invention comprises a screw, a nut, a pair of reflux elements, a reflux pipe and a roller. The nut is provided with a receiving groove and a contact surface for fitting the reflux element therein, and among the nut, a through-hole connected to the reflux hole of the reflux element is installed on the inner contact surface. . The reflux element has a roller reflux path and a reflux hole installed therein, and an end of the reflux hole has a square cross section. In addition, the reflux pipe is provided with a roller reflux path inside, and has a rectangular cross section at both ends thereof. The square cross section of the reflux element and the square cross section at both ends of the reflux pipe correspond to each other. The reflux pipe penetrates into the through hole of the nut, thereby mounting the reflux element in the receiving groove on the nut to compose the reflux system, and connecting the screw and the spiral rail on the nut to form a complete roller screw Become a system.

  With the configuration as described above, the roller screw system of the present invention has two major problems such as a poor reflux smoothness due to the curvature radius of the reflux path being too small or an increase in nut volume due to the installation of the curved pipe. Solved.

  In order to achieve the above-mentioned object, adopted technology, means or other effects, the present invention includes more preferred embodiments, and will be described in detail with reference to the drawings. I am confident that I can understand more deeply and concretely about the features or other advantages.

  2 to 6, the embodiment of the present invention includes a screw 1, a nut 2, a pair of reflux elements 3, a reflux pipe 4 and a roller 5. It is. The nut 2 is provided with an accommodation groove 22 and a contact surface 23 for fitting the reflux element 3 therein.

  Among them, the nut 2 has a through hole 21 connected to the reflux hole 30 of the reflux element 3 on the inner contact surface 23, and the reflux element 3 has a reflux path or reflux hole 30 of the roller 5 inside. The end of the reflux hole 30 has a square cross section 31.

  Further, the reflux pipe 4 is provided with a reflux path of the roller 5 therein, and has both ends 43 of square cross sections 41 that match the square cross section 31 of the reflux holes 30. There is a possibility that a relative angular difference may occur in the rectangular cross section 31 fitted to both ends of the reflux pipe 4, that is, a relative angular difference is required between the two cross sections 41 at both ends of the reflux pipe 4. Therefore, the reflux path of the both-shaped cross-section 41 of the reflux pipe 4 is formed in a torsional shape because there is a relative angular difference between the both-shaped cross-sections 31 at both ends of the reflux pipe 4. .

  A square cross section 31 of the reflux element 3 corresponds to any of the square cross sections 41 of both end portions 43 of the reflux pipe 4, and the reflux pipe 4 penetrates into the through hole 21 of the nut 2. Thus, the reflux element 3 is attached to the accommodation groove 22 on the nut 2 to constitute a reflux system. Furthermore, the connection between the screw 1 and the spiral rail on the nut 2 forms a complete roll screw system. As described above, the mutual positional relationship of the elements according to the present invention or the outline thereof.

  Among them, the created relative positions of the engagement mass 32 of the reflux element 3 and the engagement groove 42 of the reflux pipe 4 can be changed by design. The above technique is merely one simple replacement method, and will be described here.

  In order to clearly describe the implementation features of the present invention, the roller screw system described below has an inventive step or practical use over the conventional one.

  As shown in FIG. 5 and FIG. 6, it is a perspective view of the implementation state before the assembly of the present invention.

  When assembling the roller screw system of the present invention, the user first penetrates the screw 1 into the nut 2 and the spiral groove between the screw 1 and the nut 2 accommodates a relatively large number of rollers 5. A space is formed. At this time, the assembled one can form the positioning structure by fitting the engagement mass 32 of the reflux element 3 into the engagement groove 42 of the reflux pipe 4. Next, the inside of the through-hole 21 at one end of the nut 2 is further penetrated by the reflux pipe 4, and the reflux element 3 is turned from the end surface of the nut 2 and installed in the recess housing groove 22 of the nut 2.

  Further, it is pushed into the contact surface 23 of the housing groove 22 in accordance with the axial direction of the recessed housing groove 22 and is positioned on the end surface of the nut 2, and a large number of rollers 5 are positioned in the spiral groove. Finally, another one of the reflux elements 3 is installed in the recess receiving groove 22 of the nut 2 in the axial direction from the end face of the nut 2 by the same assembling step as described above, and the engagement mass 32 of the reflux element 3 is While being fitted in the engagement groove 42 of the reflux pipe 4, it can be assembled and fixed on the end surface of the nut 2.

In the present invention, in order to effectively solve the conventional agenda items related to the prior art, a technical method applied in the process of research and development is as follows.
The radius of curvature when the roller recirculates is increased to make the recirculation path smoother and improve the smoothness.
The reflux path can be installed in the nut body to reduce the volume of the entire nut.
In addition to making the injection with a stable mold on the metal of the return path of the roller, the entire return path is covered by a combination method of a plurality of members, and errors due to processing are reduced.
Since the cross section of the return path of the roller return system is square compared to the ball of the traditional rotating element, the influence of the error in the angle should always be taken into account at the part where each fitting of the return system joins. In addition, although the cross section of the return path of the ball return system is circular, it is not necessary to consider that the connection of the paths due to the angle error is not smooth.

  Therefore, the present invention can cancel the step where the cross section of the entire reflux path is not smooth by utilizing the design of the stereotaxic structure between the reflux pipe and the reflux element. Such a concept is quite different from the ball reflux system.

  Among them, in particular, there is a relative angular difference between the two cross-sections at both ends of the reflux pipe.

  In addition, the present invention reduces the complexity of machining by returning the machining contour on the nut to the same as the end plug type circulation of the ball, and using the metal fitting design to achieve the mechanism of the roller return system. Can be done.

  Further, the present invention lies in the design of the return path of the roller, and the design of the return path inside the return pipe is formed in a twisted shape.

  The entire roller path is continuously formed, and collision with the roller or collision with the turning portion does not occur, so that the overall flow smoothness is improved.

  As described above, it is possible to simultaneously solve the two major problems that the curvature of curvature of the reflux path is too small and the reflux smoothness becomes poor, or that the volume of the nut is greatly increased by installing the curved pipe.

  Accordingly, it is an object of the present invention to be applied to a roller screw, so that the smoothness of the overall reflux is improved and the reduction of the nut volume can be achieved.

  In summary, the roller screw system of the present invention comprises a screw, a nut, a pair of reflux elements, a reflux pipe and a roller. In the roller screw system in which the nut is provided with a receiving groove and a contact surface for fitting a reflux element therein, a through hole connected to the reflux hole is installed inside the nut, and the reflux pipe is a through hole of the nut. By being pierced in, the return element can be mounted in a receiving groove on the nut to harmonize the return system and connect to the screw and the helical rail on the nut for a complete roller screw system.

  Therefore, it is possible to solve the two major problems such as poor rotation smoothness due to the problem that the radius of curvature of the reflux path is too small, or the increase in nut volume due to the installation of the bending tube in the prior art, and improve the overall reflux smoothness The purpose of reducing the volume of the nut can be achieved.

  Therefore, it goes without saying that the present invention already has “industrial applicability”. In addition, the technical features disclosed in the present embodiment are not disclosed in the publications before the application, The technical features listed in the embodiments of the present invention can be used not only for public purposes, but not only have the fact that the effects as described above are enhanced, but also the additional effects cannot be overlooked. Since it is not disclosed in publications before filing and is not used for public use, and has the fact that the effect is enhanced as described above, the present invention is not limited to “novelty” or “inventive step”. Is also consistent with the patent requirements, and is expected to be filed by law and granted early through examination.

FIG. 3 is a diagram of a roller screw system disclosed in US Pat. No. 3,192,791. 1 is an overall perspective view of a roller screw system according to an embodiment of the present invention. FIG. 3 is an exploded perspective view of a reflux element and a reflux pipe of a roller screw system according to an embodiment of the present invention. It is a perspective view which shows the combined state of the reflux element and reflux pipe | tube of the roller screw system by the Example of this invention. It is a perspective view which shows the implementation state before the assembly | attachment of the roller screw system by the Example of this invention. It is a perspective view which shows the implementation state after the assembly | attachment of the roller screw system by the Example of this invention.

Explanation of symbols

<Conventional technology>
7 Nut 8 Curved tube 9 Rectangular cross section 10 Roller <Invention>
DESCRIPTION OF SYMBOLS 1 Screw 2 Nut 21 Through-hole 22 Accommodating groove 23 Contact surface 3 Reflux element 30 Reflux hole 31 Rectangular cross section 32 Locking lump 4 Reflux pipe 41 Square cross section 42 Engaging groove 43 End part 5 Roller

Claims (4)

A screw screw system comprising a screw, a nut, a pair of reflux elements, a reflux pipe and a roller, wherein the nut is provided with a receiving groove and a contact surface for fitting the reflux element therein;
The nut opens a through hole on the inner contact surface, and can be connected to the reflux hole of the reflux element,
The reflux element has a roller reflux path and a reflux hole formed therein, and an end of the reflux hole has a square cross section,
The reflux pipe is provided with a roller reflux path inside, and has a square cross section at both ends thereof,
Correspondingly to the square cross-section of the reflux element and the square cross-sections at both ends of the reflux pipe, the reflux element is installed in the accommodation groove on the nut by passing the reflux pipe through the through hole of the nut. A roller screw system, characterized in that it is a covered reflux path, and further connects the screw and the spiral rail on the nut to make a complete roller screw system.   The roller screw system according to claim 1, wherein an engagement lump and an engagement groove are formed at both ends of the reflux element and the reflux pipe, respectively.   2. The roller screw system according to claim 1, wherein there is a relative angular difference between both cross-sections at both ends of the reflux pipe.   The roller screw system according to claim 3, wherein the reflux path inside the reflux pipe is designed to be twisted.

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