JP2018128037A - Motion guide device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motion guide device capable of improving rigidity of a movable member while maintaining high waving accuracy.SOLUTION: A motion guide device comprises an endless circulation path in which a movable member 21 is assembled in a reciprocally movable manner in a length direction of a raceway member via multiple rolling bodies that are disposed so as to be freely rolled within a load rolling path formed from a rolling body rolling groove of the raceway member and a load rolling body rolling groove of the movable member 21. The motion guide device also comprises: multiple rows of rolling body circulation rows in which the multiple rolling bodies are rolled continuously; and multiple sets of double rolling body circulation rows, each set being formed from two or more adjacent rolling body circulation rows. Multiple non-load rolling body rolling paths 24 and multiple pairs of direction conversion paths are formed in the movable member 21 correspondingly to the double rolling body rolling row. On a cross section that is orthogonal with a length direction of the movable member 21, a protruding part which protrudes inside of the non-load rolling body rolling path 24 and a pair of direction conversion path is provided correspondingly to an outer shape of the double rolling body circulation row.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a motion guide device.

  2. Description of the Related Art A motion guide device that guides a linear reciprocating motion of a machine through the rotation of rolling elements is currently used in mechanical devices in all fields. Such motion guide devices have been improved in various ways in order to improve motion accuracy.

  As an improvement for improving such motion accuracy, the motion guide device described in Patent Document 1 below is known to minimize the waving phenomenon by reducing the diameter of the rolling element to increase the waving accuracy. . Moreover, although a rated load falls by reducing a diameter of a rolling element, in order to make up for this, it is known to ensure a rated load as a double row arrangement in which two or more rolling elements are provided. Note that the waving phenomenon refers to a change in posture or vibration of the moving member due to a periodic shift of the relative position of the rolling element with respect to the rolling groove.

Japanese Patent No. 5386356

  According to the motion guide device described in Patent Document 1 described above, it is effective in improving the waving accuracy. However, for example, depending on the specifications of the machine tool, the rigidity of the moving member may be required.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a motion guide device that can improve the rigidity of a moving member while maintaining high waving accuracy.

  The motion guide device according to the present invention for solving the above-described problems includes a raceway member in which a rolling element rolling groove is formed along a longitudinal direction, and a loaded rolling element rolling formed at a position facing the rolling element rolling groove. Formed by a running groove, a moving member formed with a no-load rolling element rolling path formed in parallel to the loaded rolling element rolling groove, the rolling element rolling groove and the loaded rolling element rolling groove. The moving member is assembled so as to be able to reciprocate in the longitudinal direction of the raceway member via a plurality of rolling elements that are movably arranged in the load rolling path, and the moving member is the load rolling element rolling groove. And a moving member main body in which the unloaded rolling element rolling path is formed, and a direction changing path that connects the ends of the loaded rolling element rolling groove and the unloaded rolling element rolling path are formed and the moving member main body A pair of side lids respectively attached to both ends of the In a motion guide apparatus having an infinite circulation path formed by a load rolling path, the unloaded rolling element rolling path, and a pair of the direction changing paths, a plurality of rolling element circulation rows in which the plurality of rolling elements roll together And having a plurality of sets of double row rolling element circulation rows formed by adjoining two or more rolling element circulation rows, the no-load rolling element rolling path and the pair of direction changing paths are: A plurality of the moving members are formed so as to correspond to the double row rolling element circulation row, and the no-load is provided so as to correspond to the outer shape of the double row rolling element circulation row in a cross section orthogonal to the longitudinal direction of the moving member. It is provided with the protrusion part which protrudes inward of a rolling-element rolling path and a pair of said direction change path.

  According to the present invention, the no-load rolling element rolling path and the pair of directions so that the through-hole forming the unloaded rolling element rolling path formed in the moving member corresponds to the outer shape of the rolling element circulation train in a cross-sectional shape. Since the protrusion part which protrudes inward of a conversion path is provided, the cross-sectional area of the through-hole formed in a moving member can be minimized, and the rigidity of a moving member can be ensured.

The perspective view of the exercise | movement guide apparatus which concerns on embodiment of this invention. AA sectional drawing in FIG. The B section enlarged view in FIG. These are partially expanded front views for demonstrating the double row rolling element circulation row | line and connection band which are used for the exercise | movement guide apparatus which concerns on embodiment of this invention. It is a figure which shows the 1/4 symmetry model used for the analysis, (a) is an Example, (b) is a figure which shows a comparative example. The graph showing the experimental result which compared the horizontal displacement and the vertical displacement of the moving member of the movement guide apparatus which concerns on embodiment of this invention with the prior art example.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of a motion guide device according to the 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. .

  1 is a perspective view of a motion guide apparatus according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line AA in FIG. 1, and FIG. 3 is an enlarged view of a portion B in FIG. 4 is a partially enlarged front view for explaining a double row rolling element circulation row and a connection band used in the motion guide apparatus according to the embodiment of the present invention, and FIG. 5 is a 1/4 symmetry used for the analysis. It is a figure which shows a model, (a) is an Example, (b) is a figure which shows a comparative example, FIG. 6 shows the horizontal displacement and vertical displacement of the moving member of the movement guide apparatus which concern on embodiment of this invention. It is a graph showing the experimental result compared with the prior art example.

  As shown in FIG. 1, the motion guide device 1 according to the present embodiment is assembled to the track member 10 via a track member 10 having a rolling element rolling groove 11 in the longitudinal direction and a plurality of rolling elements 30. And a moving member 20 that reciprocates linearly along the rolling element rolling groove 11.

  The race member 10 has a plurality of bolt holes 12 drilled from the top surface 13 toward the bottom surface 14. The motion guide apparatus 1 according to the present embodiment is fastened to a counterpart component such as a base by inserting bolts into the plurality of bolt holes 12 formed in the track member 10. The track member 10 is a long member having a substantially rectangular cross section, and is a member in which a rolling element rolling groove 11 extending in the longitudinal direction is formed on the surface thereof. The rolling element rolling groove 11 is described later. It is possible to receive a load from a spherical rolling element 30 disposed between the moving member 20 and the moving member 20. Moreover, the cross section orthogonal to the longitudinal direction of the rolling element rolling groove 11 is formed in an arc shape with such an accuracy that smooth rolling of the rolling element 30 can be realized. The rolling elements 30 constitute a double row rolling element circulation row 35 in which two adjacent rows of rolling element circulation rows 34 form a set, and correspond to the double row rolling element circulation row 35. A total of eight moving body rolling grooves 11 are formed.

  The moving member 20 has a substantially U-shaped cross section so as to straddle the top surface 13 and the left and right side surfaces of the track member 10, and 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 attached to each other. The moving member main body 21 is preferably made of a material having high strength such as steel, and the side cover 22 is preferably made of synthetic resin or the like.

  The moving member main body 21 and the side lid 22 have a central portion facing the top surface 13 of the track member 10 and a pair of leg portions facing both the left and right side surfaces of the track member 10. As shown in FIG. 2, the moving member main body 21 has, for example, a total of eight load rolling element rolling grooves 23 extending in the longitudinal direction of the race member 10 so as to face the rolling element rolling grooves 11 of the race member 10. Is formed.

  The moving member main body 21 is formed with a total of four unloaded rolling element rolling paths 24 extending in parallel with the loaded rolling element rolling grooves 23. The no-load rolling element rolling path 24 is configured to pass through the above-described double row rolling element circulation train 35 one by one.

  As shown in FIG. 3, the no-load rolling element rolling path 24 is formed in the moving member 20 so as to correspond to the double row rolling element circulation row 35, and corresponds to the outer shape of the double row rolling element circulation row 35. Thus, it is formed in the shape provided with the protrusion part 26 which protrudes inward. The cross-sectional shape of the unloaded rolling element rolling path 24 will be described in detail. Since the protrusions 26 are arranged so that the rolling element circulation rows 34 adjacent to each other overlap as will be described later, this double row rolling element circulation. The protruding portion 26 is formed so as to correspond to the cross-sectional shape of the row 35. In this way, the unloaded rolling element rolling path 24 includes the protruding portion 26 projecting inward, whereby the cross-sectional area of the unloaded rolling element rolling path 24 formed on the moving member 20 can be minimized, and the movement The rigidity of the member 20 can be ensured.

  In addition, as a processing method of the no-load rolling-element rolling path 24 which has such a protrusion part 26, it is suitable to process so that a 2nd hole may be connected with a long end mill, for example, after processing 1 hole with a drill etc.

  Further, a U-shaped direction changing path 25 that connects one end of the loaded rolling element rolling groove 23 and one end of the no-load rolling element rolling path 24 is formed in the side lid 22. An infinite circuit consisting of a loaded rolling element rolling path consisting of the rolling element rolling groove 11 and a loaded rolling element rolling groove 23, a pair of direction changing paths 25 and an unloaded rolling element rolling path 24 is formed.

  Since the rolling element 30 is interposed between the rolling element rolling groove 11 and the load rolling element rolling groove 23, the motion guide apparatus 1 according to the present embodiment moves the moving member 20 in the longitudinal direction of the track member 10. When it is moved along, a rolling motion can be performed. The rolling element 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 25. The rolling element 30 whose direction of travel is changed by the direction changing path 25 rolls on the no-load rolling element rolling path 24, passes through the other direction changing path 25, and is then returned to the loaded rolling element rolling path again. Thus, the rolling element 30 rolls to realize infinite circulation.

  Moreover, as shown in FIG. 4, the ball | bowl formed in the spherical shape is used suitably for the some rolling element 30. FIG. Further, the plurality of rolling elements 30 include a coupling band composed of a spacer portion 32 disposed between adjacent rolling elements 30 and a band-shaped coupling portion 33 that connects the spacer portions 32 arranged along the longitudinal direction thereof. 31 is held. Thus, the collision between the rolling elements 30 can be prevented by the spacers 32 arranged between the rolling elements 30. Further, since the rolling elements 30 are connected and held in series by the connecting band 31, they can roll while the rolling elements 30 are aligned.

  The rolling element 30 forms a rolling element circulation train 34 formed by rolling of the plurality of rolling elements 30, and the rolling element circulation trains 34, 34 adjacent to each other form a pair to form a double row rolling element. A circulation train 35 is formed. At this time, the adjacent rolling element circulation rows 34 and 34 are arranged so as to be shifted from each other along the longitudinal direction, and are arranged so as to overlap each other in a cross section orthogonal to the longitudinal direction. By arranging the row 34, the width direction dimension of the double row rolling element circulation row 35 is minimized. By minimizing the width dimension of the double row rolling element circulation row 35, the cross-sectional area of the no-load rolling element rolling path 24 formed in the moving member 20 is minimized to ensure the rigidity of the moving member 20. In addition, since the double row rolling element circulation row | line 35 comprises the rolling element circulation row | line | columns 34 and 34 which adjoin each other, it synchronizes circulation of the rolling element 30 between adjacent rolling element circulation row | line | columns 34 and 34. FIG. Since the rolling elements 30 that roll on the unloaded rolling element rolling path are synchronized, the stability of the reciprocating motion of the moving member 20 is increased, and waving can be suppressed.

  In the cross section in the width direction of the motion guide device 1, the rolling element rolling groove 11 and the loaded rolling element rolling groove 23 are formed in a circular arc shape having a single curvature larger than the curvature radius of the rolling element 30. It is preferable that

  As shown in FIG. 6, the motion guide device 1 according to the present embodiment configured as described above has improved rigidity in both horizontal displacement and vertical displacement. In this analysis, as shown in FIG. 5 (b), the comparative shape as a comparative example is such that the double-row rolling element circulation train can be inserted through the no-load rolling element rolling path in the cross section orthogonal to the longitudinal direction of the moving member. FIG. 5A is a simulation result using a 1/4 symmetric model when formed with a no-load rolling element rolling path on a single circle that is slightly larger than the width dimension of the double row rolling element circulation row. As described above, the present invention as an embodiment is a 1/4 symmetric model in the case where a no-load rolling element rolling path having a cross-sectional shape provided with a protrusion corresponding to the outer shape of the double row rolling element circulation row is formed on the moving member. It was analyzed using. The material of the moving member 20 is steel, the Young's modulus is 207 GPa, the Boisson ratio is 0.3, and a load of 5000 N is applied to the loaded rolling element rolling groove from a 45 ° oblique direction as shown by the arrow in the figure. This is an analysis of the horizontal displacement and vertical displacement of the moving member.

  As is clear from FIG. 6, the motion guide apparatus 1 according to the present embodiment has a decrease of 14.1% in horizontal displacement and a decrease of 6% in vertical displacement when subjected to a predetermined load, respectively. It could be confirmed. Thus, it can be confirmed that the rigidity against horizontal displacement is particularly improved as compared with the comparative example, and this can suppress the displacement of the pair of leg portions of the moving member 20 in the opening direction. Is shown. Thus, since it has high rigidity with respect to deform | transforming so that a leg part may open, even if it is a case where a high load is loaded, it becomes possible to maintain highly accurate guidance.

  Thus, by forming the no-load rolling element rolling path 24 provided with the protrusion part 26 which protrudes inward corresponding to the external shape of the double row rolling element circulation row 35 on the moving member 20, the double row rolling element The rigidity of the moving member can be ensured without hindering the effect of suppressing waving by the circulation train.

  In the above-described embodiment, the case where the double row rolling element circulation row 35 is composed of two adjacent rolling element circulation rows 34 and 34 has been described. If it consists of the above rolling element circulation row | line | column, you may comprise from three or more rolling element circulation row | line | columns. 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 Movement guide apparatus, 10 Track member, 11 Rolling body rolling groove, 20 Moving member, 23 Load rolling body rolling groove, 24 Unloaded rolling body rolling path, 26 Protruding part, 30 Rolling body, 31 Connection belt, 33 Connection Part, 34 rolling element circulation train, 35 double row rolling element circulation train.

Claims (4)

A raceway member in which rolling element rolling grooves are formed along the longitudinal direction;
A loaded rolling element rolling groove formed at a position facing the rolling element rolling groove, and a moving member formed with an unloaded rolling element rolling path formed in parallel with the loaded rolling element rolling groove;
The moving member reciprocates in the longitudinal direction of the track member via a plurality of rolling elements which are arranged to freely roll in a load rolling path formed by the rolling element rolling groove and the load rolling element rolling groove. Assembled to be movable,
The moving member is a moving member main body in which the loaded rolling element rolling groove and the unloaded rolling element rolling path are formed,
A direction change path that connects the ends of the loaded rolling element rolling groove and the unloaded rolling element rolling path is formed, and a pair of side covers that are respectively attached to both ends of the moving member body,
In the motion guide device having an infinite circuit formed by the loaded rolling path, the unloaded rolling element rolling path and the pair of direction changing paths,
A plurality of rolling element circulation trains in which the plurality of rolling elements roll in a row and a plurality of one row double rolling element circulation trains formed by adjoining two or more rolling element circulation trains are provided. And
The no-load rolling element rolling path and the pair of direction changing paths are formed in the moving member so as to correspond to the double row rolling element circulation row, and in the cross section orthogonal to the longitudinal direction of the moving member, A motion guide device comprising a protruding portion protruding inwardly of the unloaded rolling element rolling path and the pair of direction changing paths so as to correspond to the outer shape of the row rolling element circulation row. The motion guide device according to claim 1,
The double row rolling element circulation row includes two rows of rolling element circulation rows adjacent to each other,
The cross section of the unloaded rolling element rolling path is formed such that adjacent rolling element circulation trains overlap each other. The motion guide apparatus according to claim 1 or 2,
In the double row rolling element circulation train, the adjacent rolling element circulation trains are arranged so as to be shifted from each other in the longitudinal direction. In the exercise | movement guide apparatus of any one of Claim 1 to 3,
The double-row rolling element circulation row includes a connection band that connects the rows.