JP5890514B2 - Roller and rolling guide device using this roller - Google Patents

Description

  The present invention relates to a roller and a rolling guide device provided with a moving member that is movably assembled along a track member using the roller.

  Conventionally, a track member in which a rolling surface is formed along the longitudinal direction, a load rolling element rolling surface facing the rolling surface, and a moving member assembled so as to be movable with respect to the track member, A rolling guide device having a plurality of rolling elements that roll between a rolling surface and a loaded rolling element rolling surface, for example, a ball or a cylindrical roller, is known. Further, regarding a cylindrical roller having a single rotating shaft, such a cylindrical roller can be loaded by making line contact with the rolling surface, so that the allowable load is set larger than that of the ball. It has the advantage of being able to.

JP 2005-163882 A

  However, in such a rolling guide device using a cylindrical roller, for example, if an excessive moment is applied to the moving member, the rolling surface and the roller are not parallel, and a component force is generated in the axial direction of the roller. . Therefore, there is a possibility that the roller will be in a state of uneven contact and the function of the rolling guide device cannot be fully exhibited. Here, the uneven contact of the roller means a state in which the stress at the end of the roller in the axial direction exceeds the stress at the center.

  The present invention has been made to solve the above-described problems, and includes a roller that does not cause uneven contact even when an excessive moment is applied, and a rolling guide device incorporating this roller. The purpose is to provide.

The roller according to the present invention is a roller having a single rotating shaft, and the roller is a rolling surface so as to gradually reduce the diameter along the rotating shaft from both end surfaces in the rotating shaft direction to the center of the roller. A recess is formed on the both end faces toward the center of the roller. The relationship between the ratio of the diameter of the roller to the depth of the recess and the allowable load in a range where the roller does not strike is provided. the depth of the recess, characterized that you have set the diameter of the as the ratio of the depth of the recess is greater than or equal to a value indicating a peak of the allowable load of the roller.

  According to the present invention, the roller is formed in a drum shape, and the concave portions are formed on both end surfaces in the rotation axis direction. Therefore, the roller end portion is deformed, and the roller does not cause uneven contact. It is possible to provide a rolling guide device capable of smoothly circulating an infinite number of rollers.

The perspective view which shows the rolling guide apparatus which concerns on the 1st Embodiment of this invention. The front view which shows the roller used for the rolling guide apparatus which concerns on the 1st Embodiment of this invention. Sectional drawing of the roller which concerns on the 1st Embodiment of this invention. The expanded sectional view for demonstrating the shape of the recessed part of the roller which concerns on the 1st Embodiment of this invention. The conceptual diagram which shows the deformation | transformation state of the roller which concerns on the 1st Embodiment of this invention. The analysis result which shows the contact surface pressure of the edge part of the roller which concerns on the 1st Embodiment of this invention. Sectional drawing which shows the modification of the roller which concerns on the 1st Embodiment of this invention. Sectional drawing of the roller which concerns on the 2nd Embodiment of this invention. Sectional drawing of the roller which concerns on the 3rd Embodiment of this invention. The analysis result which showed the relationship between the ratio of the depth Dd of the recessed part of the roller which concerns on the 1st Embodiment of this invention, the roller diameter Dw, and the allowable load in the range which the roller does not strike. The analysis result which showed the relationship between the ratio of the depth Dd of the recessed part of the roller which concerns on the 1st Embodiment of this invention, the roller diameter Dw, and the angle (theta) of the slope 34. FIG. The relationship between the ratio of the roller recess depth Dd and the roller diameter Dw, in which the roller diameter and the roller length of the roller used in FIG. Analysis results shown. The analysis result which showed the relationship between the ratio (theta) of the inclined surface 34 and the ratio of the depth Dd of the recessed part of the roller which changed the roller diameter of the roller used in FIG. 11 and the length of the roller 1.5 times, and the roller diameter Dw.

[First Embodiment]
Hereinafter, embodiments of a rolling guide device according to the present invention will be described with reference to the drawings. The following embodiments do not limit the invention according to each claim, and all combinations of features described in the embodiments are not necessarily essential to the solution means of the invention. .

  FIG. 1 is a perspective view showing a rolling guide apparatus according to the first embodiment of the present invention, and FIG. 2 is a front view showing a roller used in the rolling guide apparatus according to the first embodiment of the present invention. FIG. 3 is a cross-sectional view of the roller according to the first embodiment of the present invention.

  As shown in FIG. 1, the rolling guide device 1 according to the present embodiment includes a raceway member 10 having a plurality of rolling surfaces 11 formed on the outer surface along the longitudinal direction, and a load facing the rolling surface 11. A rolling element rolling surface 23 is formed, and the moving member 20 is assembled to the raceway member 10 through a plurality of rollers 30 so as to be able to reciprocate.

  As shown in FIG. 2, the roller 30 is a roller having a single rotation axis A, and is formed into a drum shape that gradually decreases in diameter from both axial end faces 31a and 31b toward the center. The rolling surface 30a of the roller 30 viewed from the axial direction and the vertical direction is formed in a curved shape having a curvature radius R.

  A plurality of bolt holes 12 are drilled in the race member 10 from the upper surface to the bottom surface. In the rolling guide device 1 according to the present embodiment, bolts are inserted into the plurality of bolt holes 12 formed in the track member 10 and fastened to the base. The track member 10 is a long member having a substantially rectangular cross section, and two rolling surfaces 11 are formed symmetrically on both the left and right sides.

  The moving member 20 has a substantially U-shaped cross section so as to straddle the upper surface and the left and right side surfaces of the track member 10, and is attached to the moving member main body 21 and both end faces that are the reciprocating direction of the moving member main body 21. And a pair of side lids 22.

  The moving member main body 21 and the side lid 22 have a central portion that faces the upper surface of the track member 10 and a pair of leg portions that face the left and right side surfaces of the track member 10. For example, a total of four rolling rolling element rolling surfaces 23 extending in the longitudinal direction of the track member 10 are formed on the moving member main body 21 so as to face the rolling surface 11 of the track member 10.

  Further, a total of four rolling element return passages 24 extending in parallel to the load rolling element rolling surface 23 are formed in the moving member main body 21.

  In addition, a U-shaped direction changing path 29 that connects one end of the load rolling element rolling surface 23 and one end of the rolling element return passage 24 is formed in the side lid 22. An infinite circuit consisting of a loaded rolling element rolling path composed of the rolling surface 11 and a loaded rolling element rolling surface 23, a pair of direction changing paths 29 and a rolling element return path 24 is formed.

  In the rolling guide device 1 according to the present embodiment, since the roller 30 is interposed between the rolling surface 11 and the loaded rolling element rolling surface 23, the moving member 20 is moved along the longitudinal direction of the track member 10. By doing so, a rolling exercise can be performed. The roller 30 that has rolled to one end of the loaded rolling element rolling path is lifted up by the upper part of the ridge formed on the side lid 22 and guided to one direction changing path 29. The roller 30 whose direction of travel is changed by the direction changing path 29 rolls on the rolling element return path 24, passes through the other direction changing path 29, and is then returned to the load rolling element rolling path again. Thus, the roller 30 rolls to realize infinite circulation.

  Further, the plurality of rollers 30 are held by a belt-like retainer including a spacer portion disposed between adjacent rollers 30 and a belt-like connecting band 32 that connects the spacer portions via both end faces of the roller 30. . As described above, the spacers disposed between the rollers 30 can prevent the rollers 30 from colliding with each other. Further, since the rollers 30 are connected and held in series by the connecting band 32, the rollers 30 can roll while being aligned.

  Note that the cross-sectional shapes of the rolling surface 11 and the loaded rolling element rolling surface 23 are arcuately convex toward the loaded rolling element rolling surface 23 or the rolling surface 11 so as to correspond to the drum shape of the roller 30. Is formed. The rolling surface 11 and the loaded rolling element rolling surface 23 via the roller 30 have, for example, an angular contact structure in which each contact line is formed at a contact angle of 45 °. In addition, a contact angle line means the line which connected the point which the rolling surface 11 and the load rolling-element rolling surface 23 contact via the roller 30. FIG.

  Next, the shape of the roller 30 according to the present embodiment will be described with reference to FIG. As shown in FIG. 3, concave portions 31 formed along the rotation axis A direction are formed on both end faces 31 a and 31 b in the rotation axis A direction of the roller 30 according to this embodiment.

  Moreover, as shown in FIG. 3, the recessed part 31 has the bottom face 33 formed in the position of predetermined depth D from the both end surfaces 31a and 31b along a rotating shaft, for example, and an opening end is recessed part diameter (phi) 2. It is formed in the formed truncated cone shape. Since the recess 31 is formed on both end faces 31 a and 31 b of the roller 30, the depth D of the recess 31 is less than half of the length of the roller 30 in the longitudinal direction so that the roller 30 does not penetrate in the longitudinal direction by the recess 31. Formed.

  The recess diameter φ2 is smaller than the rolling element diameter φ1 at the end faces 31a and 31b, and the outer edge 32 is formed on the end faces 31a and 31b of the roller 30. The recess diameter φ2 is formed to be about 1 mm smaller than the rolling element diameter φ1, and the thickness of the outer edge portion 32 is thereby formed to about 0.5 mm. The thickness of the outer edge portion 32 does not depend on the size of the rolling element diameter φ1, and it has been obtained from the analysis by the inventors that the outer edge portion 32 only needs to be formed at about 0.5 mm.

  FIG. 4 is an enlarged cross-sectional view for explaining the shape of the concave portion of the roller according to the first embodiment of the present invention. As shown in FIG. At a position where an imaginary line S, which is an extension line of a slope inclined by a predetermined angle, and an extension line B of the bottom surface 33 are continuous, a maximum arc Rmax composed of the imaginary line S and the extension line B of the bottom surface 33 is formed. Yes.

  When the roller 30 formed in this way receives a load in the radial direction, the roller 30 is elastically deformed at a contact portion with the rolling surface 11 according to the load. FIG. 5 is a conceptual diagram showing a deformed state of the roller according to the first embodiment of the present invention. Specifically, as shown in FIG. At the end surfaces 31 a and 31 b, the roller 30 is elastically deformed in the M direction by a rotational moment that is opposed to the arc shape of the rolling surface 11 and the side surface of the roller 30.

  At the same time, the roller 30 according to the present embodiment has the recess 31 formed at the end in the rotation axis direction, so that the outer edge 32 is also elastically deformed in the arc direction My on the side surface of the roller 30. Due to the elastic deformation along the arc direction My, the end portion of the roller 30 is elastically deformed outside the contact portion with the rolling surface 11. This elastic deformation realizes relaxation of stress concentration, and stress concentration at the end portion and uneven contact of the roller 30 corresponding to the stress concentration do not occur.

  FIG. 6 is an analysis result showing the contact surface pressure of the end portion of the roller according to the first embodiment of the present invention, and the contact along the rotation axis direction when the roller 30 according to this embodiment applies a load. The surface pressure (Example 1) was an analysis result as shown in FIG. In this analysis, a roller having a distance (axial length) from one end face to the multi-end face in the rotation axis direction of 7 mm and a roller diameter Dw of 4 mm was used. As shown in FIG. 6, it can be seen that the contact surface pressure gradually decreases toward the end portion of the contact portion, and the contact surface pressure increases at the end portion. However, the increased contact surface pressure does not exceed the contact surface pressure at the central portion in the direction of the rotation axis, and no contact occurs at the roller end. Further, the contact surface pressure of the roller 30 according to the present embodiment is such that the contact surface pressure exceeds 4000 MPa in the same manner as the contact surface pressure at the end when the crowning is formed at the end of the cylindrical roller described as Conventional Example 1. It can be seen that there is no eccentric contact.

  Further, the lower part of FIG. 6 (Example 2 and Conventional Example 2) shows the rolling when the roller 30 according to this embodiment and the roller when the crowning is formed at the end of the cylindrical roller are incorporated in the rolling guide device. Each stress distribution when 10% of the load actually received by the roller is assumed with respect to the basic dynamic load rating of the guide device is shown. In Conventional Example 2, the contact surface pressure is reduced at the roller end, and the stress value is generally high because the contact area is reduced without contacting the roller end. In addition, the contact surface pressure starts to drop from around 60% of the contact portion position, but this portion is the crowning start point where the crowning is formed, and there are places where the stress value always increases at the straight portion and the crowning start point. End up. On the other hand, in Example 2, the stress is uniformly distributed to the end. It can be seen that the roller is in contact with the end and the stress area is generally low as the contact area increases. As described above, the roller 30 according to the present embodiment has a generally low stress value as compared with the conventional example, so that the life of the roller becomes long, and when incorporated in a rolling guide device or the like, the product life or The maintenance period can be extended.

  As described above, in the roller 30 according to the present embodiment, the rolling surface 30a is formed in a drum shape, and the recesses 31 are formed in the both end surfaces 31a and 31b in the rotation axis direction. When the load is applied, it is possible to deform the outer edge portion 32 where the uneven contact occurs, thereby reliably suppressing the occurrence of the uneven contact.

  In the roller 30 according to the present embodiment, the case where the inner side surface 35 of the truncated cone-shaped recess 31 is formed in the maximum arc Rmax has been described. However, as illustrated in FIG. Instead, it may be formed as the slope 34 inclined at the same angle as the virtual line S. FIG. 7 is a cross-sectional view showing a modified example of the roller according to the first embodiment of the present invention.

[Second Embodiment]
In the rolling guide device 1 according to the first embodiment described above, the case where the concave portion 31 is formed in a truncated cone shape has been described. The roller according to the second embodiment to be described next will explain an example of a recess having a form different from that of the first embodiment. Note that members that are the same as or similar to those in the first embodiment described above are given the same reference numerals, and descriptions thereof are omitted.

  FIG. 8 is a cross-sectional view showing a roller 30 ′ according to the second embodiment. As shown in FIG. 8, the roller 30 ′ according to the second embodiment is different from the roller 30 according to the first embodiment in the shape of the recess 31 ′. Specifically, in the roller 30 ′ according to the second embodiment, the shape of the recess 31 ′ is formed in a conical shape.

  The recess 31 ′ has a slope 34 inclined at a predetermined angle from the rotation axis, and the conical tip portion is formed in a maximum arc Rmax composed of slopes 34 intersecting each other. The recess 31 'is formed with a depth D2 from the end faces 31a and 31b of the roller 30'.

  Further, the opening ends of the recesses 31 ′ on the side of the end surfaces 31 a and 31 b of the roller 30 ′ are formed with a diameter smaller than the outer diameter of the end surfaces 31 a and 31 b, and the outer edge portions 32 are formed on the end surfaces 31 a and 31 b.

  As described above, the roller 30 ′ according to the present embodiment has the concave portion 31 ′ formed in a conical shape, so that the deformation at the outer edge portion 32 of the concave portion 31 ′ can be increased, and the occurrence of uneven contact can be more reliably generated. Can be suppressed.

[Third Embodiment]
In the roller 30 ′ according to the second embodiment described above, the case where the concave portion 31 ′ is formed in a conical shape has been described. The roller according to the third embodiment to be described next will explain an example of a recess having a form different from that of the second embodiment. In addition, about the member same or similar to the case of the 1st and 2nd embodiment mentioned above, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  FIG. 9 is a cross-sectional view showing a roller 30 ″ according to the third embodiment. As shown in FIG. 9, the roller 30 ″ according to the third embodiment is different from the rollers 30 and 30 ′ according to the first and second embodiments in the shape of the recess 31 ″. Specifically, the roller 30 ″ according to the third embodiment is formed in a semi-elliptical shape in which the shape of the recess 31 ″ has a depth D3.

  Further, the opening ends of the recesses 31 ″ on the side of the end surfaces 31a and 31b of the roller 30 ″ are formed to have a diameter smaller than the outer diameters of the end surfaces 31a and 31b, and an outer edge portion 32 is formed on the end surfaces 31a and 31b. .

  Thus, since roller 30 '' concerning this embodiment has formed crevice 31 '' in the shape of a semi-ellipse, crevice 31 '' can be processed easily.

  Next, referring to FIGS. 10 and 11, the relationship between the ratio between the depth Dd of the concave portion of the roller 30 and the roller diameter Dw of the roller 30 according to the first embodiment and the allowable load within a range where no roller contact occurs, and the depth An analysis result obtained by analyzing the relationship between the ratio of the thickness Dd and the roller diameter Dw and the angle θ of the inclined surface 34 will be described.

  As a result, in the relationship between the ratio of the depth Dd of the concave portion 31 of the roller 30 to the roller diameter Dw and the allowable load P in the range where the roller 30 is not biased, Dd / Dw is the maximum value that is the peak value of the allowable load P. When the depth Dd of the concave portion 31 of the roller is set so as to be equal to or greater than the value X indicating the allowable load, the result is that the roller is not caused to strike and the allowable load can be increased.

Further, it has been found that in the usable region as shown in FIG. 11, the outer edge portion 32 is elastically deformed and does not cause uneven contact. Among these, as shown in FIG. 10, in the case of the roller 30 according to the first embodiment in which the concave portion is formed in a truncated cone shape, the value obtained by plotting the value at which the allowable load is the largest among the angles θ of the inclined surfaces 34 is plotted. When the angle θ was formed so that the height D was larger than Dd / Dw derived from the following equation, the roller was not caused to strike, and the allowable load could be increased.

  Next, the analysis results shown in FIGS. 12 and 13 are analysis results obtained by analyzing a roller in which the diameter and length of the roller analyzed in FIGS. 10 and 11 are both increased 1.5 times. In addition, about the thickness of the outer edge part 32, the diameter of the recessed part was formed large so that it might become the thickness similar to the roller which analyzed in FIG.

  As can be seen from this analysis result, even if the roller diameter and length are changed, the ratio between the depth Dd of the recess 31 of the roller 30 and the roller diameter Dw and the allowable load P in the range where the roller 30 does not strike off. When the depth Dd of the concave portion 31 of the roller is set so that Dd / Dw is equal to or greater than the value X indicating the maximum allowable load that is the peak value of the allowable load P, the roller will not be biased. And the result that an allowable load can be taken large was obtained.

In addition, as shown in FIG. 13, when the angle θ is formed so that the depth D is larger than Dd derived from the following formula as a result of plotting the value of the maximum allowable load among the angles θ of the slope 34. However, the result was that the roller did not cause uneven contact and the allowable load could be increased. As can be seen from this equation, when the diameter or length of the roller is changed, the relationship between the angle θ and the recess depth Dd / Dw changes.

  In this way, by setting the depth and the slope angle in accordance with the shape of the recess, it is possible to set a large allowable load and to obtain a roller that does not cause uneven contact at the roller end. Specifically, the depth Dd of the concave portion is set so that the allowable load is set large when the angle of the inclined surface is θ and the number is larger than the number 1 satisfying the above-mentioned formula 1, and the uneven contact at the roller end portion is not caused. I understand.

  The motion guide apparatus according to the present embodiment described above is used in the field of industrial machines such as machine tools, semiconductor / liquid crystal manufacturing apparatuses (for example, mounting machines), robots, etc. It can be incorporated as a component part in a wide range of fields, including consumer products such as machinery, food machinery, and conveyors.

  The present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the present invention. For example, in this embodiment, the case where the raceway member is formed in a rectangular cross section has been described, but the shape of the raceway member is not limited to this, and can be appropriately changed according to required rigidity and workability. Moreover, although the rolling guide apparatus 1 which concerns on this embodiment demonstrated the case where a strip | belt-shaped retainer was applied, it is not restricted to this, You may comprise as a total roller which does not apply a strip | belt-shaped retainer, and it is a spacer between adjacent rollers. Can also be interposed. In addition to the rolling guide device, the present invention has, for example, an inner member having a raceway surface on the outer surface and a load raceway surface facing the raceway surface of the inner member, and is disposed outside the inner member. The present invention can also be applied to a rolling guide device such as a rotary bearing, which is disposed between the raceway surface and the load raceway surface in a rolling guide device having an outer member.

  Moreover, although the case where the rolling surface 11 formed a total of 4 strip | lines was demonstrated, the number of the rolling surfaces 11 is not restricted to this, It is possible to change suitably according to the required rigidity and load. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  DESCRIPTION OF SYMBOLS 1 Rolling guide apparatus, 10 Track member, 20 Moving member, 30, 30 ', 30' Roller, 31, 31 ', 31' 'Recessed part, 31a, 31b End surface, 32 Outer edge part, 33 Bottom face, 34 Slope, A Rotating shaft , D depth.

Claims (3)

A roller having a single axis of rotation,
The roller has a rolling surface formed so that the diameter gradually decreases along the rotation axis from both end surfaces in the rotation axis direction to the center of the roller.
The both end surfaces are formed with a recess toward the roller center ,
In the relationship between the ratio of the diameter of the roller and the depth of the recess and the allowable load in a range where the roller does not strike unevenly, the ratio of the diameter of the roller and the depth of the recess has a peak of the allowable load of the roller. rollers depth of the recess to a value above indicated features that you have been set. The roller according to claim 1 ,
An inner member having a raceway surface on the outer surface;
A rolling guide device having a load raceway surface opposite to the raceway surface of the inner member and having an outer member disposed outside the inner member, rolls between the raceway surface and the load raceway surface. A rolling guide device characterized by being arranged freely. A roller according to claim 1 , wherein the roller is interposed between a raceway member having a rolling surface and extending in a longitudinal direction, and a movable member assembled in a movable manner with respect to the raceway member. Guide device.

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