JP2013092235A - Rolling guide device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling guide device capable of highly accurately guiding a moving body being a carrying object, by effectively restraining waving caused in a moving block caused as a rolling element goes in and out of a load passage.SOLUTION: This rolling guide device includes a track rail formed with a plurality of rolling surfaces of the rolling elements along the longitudinal direction, and the moving block having a plurality of load rolling surfaces for constituting the load passages of the rolling elements by opposing to the rolling surfaces, and each of the load rolling surfaces havs a pair of crowning areas arranged on both ends in its longitudinal direction and an effective load area positioned between the crowning areas. The moving block includes at least two kinds of the load rolling travel surfaces different in boundary positions between the crowning area and the effective load area.

Description

  The present invention relates to a rolling guide device in which a moving member and a guide shaft are movably assembled via a large number of rolling elements such as balls and rollers.

  As this type of rolling guide device, a track rail as a guide shaft laid on a fixed portion of a mechanical device, a moving block as a moving member assembled to the track rail via a number of balls as rolling elements, What is composed of is known. The track rail has a rolling surface of the ball along its longitudinal direction, while the moving block has a load rolling surface that constitutes a load path facing the rolling surface of the track rail, The moving block is configured to move along the track rail when the ball moves in and out of the load passage while rolling. Further, as a structure for allowing the ball to enter and exit from the load passage, the moving block is provided with an infinite circulation path for the ball, or a ball cage longer than the moving block is connected to the moving block and the track. What is interposed between rails is known.

  An example in which an infinite circulation path for balls is provided for the moving block will be described. The infinite circulation path includes a load path through which the ball rolls while applying a load between the track rail and the moving block. A rolling element return path provided in parallel with the load path, and a pair of direction change paths connecting the ends of the load path and the rolling element return path, each direction change path is a ball rolling In order to change the direction by 180 °, it is formed in a substantially semicircular shape. The rolling element return passage and the direction change passage are configured as unloaded passages in which the balls roll while being released from the load, and the inner diameters of these passages are formed larger than the ball diameter.

  When the moving block moves along the track rail, the ball existing in one of the direction change paths enters the load passage, and loads a load acting between the moving block and the track rail in the load passage. Roll over. After that, the ball that has finished rolling through the load passage is discharged from the load passage to the other direction change passage and is in a no-load state.

  On the other hand, in an example in which a ball cage is provided between the moving block and the track rail, the ball cage is formed to be longer than the entire length of the moving block, and a large number of balls roll there at predetermined intervals. Since the moving blocks move along the track rail, the moving blocks move at half the speed of the moving blocks of the ball cage, and the balls arranged in the ball cage are successively moved. The load enters the load passage and is loaded. In addition, the balls that have finished rolling through the load passage are discharged from between the moving block and the track rail while being arranged in the ball cage, and become unloaded.

  The load acting between the moving block and the track rail is loaded by balls rolling in the load passage, and the load acting on each ball is the number of balls simultaneously existing in the load passage. Will change. Since each ball undergoes elastic deformation according to the applied load, when the ball enters and exits the load passage, the amount of elastic deformation of the ball changes accordingly, and the moving block that moves on the track rail undergoes minute vibration. (Hereinafter referred to as “waving”). The waving generated in the moving block is extremely small with an amplitude of about 0.1 to 0.3 μm. However, in a rolling guide device employed in a machine tool or the like that requires ultra-fine machining accuracy, Reduction is an important issue.

  Conventionally, as a countermeasure for reducing waving, a so-called crowning process for a load rolling surface of the moving block is known. In this crowning process, both ends in the longitudinal direction of the load rolling surface are ground excessively compared to the center, and the ball is moved from the unloaded state to the loaded state or from the loaded state to the unloaded state in the ground region where the grinding has been excessively performed. Transition to the state. That is, when crowning treatment is applied to the load rolling surface, a large load does not suddenly act on the ball that has entered the load passage, and the ball gradually changes from the unloaded state to the loaded state. Therefore, it is possible to suppress the waving.

  Moreover, in the moving body guide apparatus disclosed in Japanese Patent Application Laid-Open No. 2004-58269, the movement of the moving body is supported by a plurality of moving blocks, while the waving of each moving block is approved. We aim to reduce waving that propagates to the body. Specifically, three or five moving blocks are arranged on two parallel track rails to support the linear motion of the moving body, and these moving blocks are one or more triangles on the bottom surface of the moving body. The moving blocks are arranged so as to constitute

JP 2004-58269 A

  However, in the above-described crowning process for the load rolling surface of the moving block, the optimum values of the length and depth of the crowning region provided at both ends of the load rolling surface are different depending on the usage conditions of the rolling guide device. Therefore, if the same crowning process is performed on all the moving blocks to be produced, the effect of suppressing waving was limited.

  Further, the suppression of waving by using a plurality of moving blocks as disclosed in Patent Document 1 does not fundamentally solve the occurrence of waving in each moving block, and only one track rail is used. There was a problem that it could not be applied to a linear guide that could be completed.

  Such a problem related to waving is not limited to the case where a ball is used as a rolling element that rolls in the load passage of the moving block, and similarly occurs when a roller is used.

  The present invention has been made in view of such problems, and the object of the present invention is to effectively suppress waving that occurs in the moving block due to the rolling elements entering and exiting the load passage, and to convey objects. An object of the present invention is to provide a rolling guide device capable of guiding a moving body that is a high accuracy.

  That is, the rolling guide device of the present invention includes a track rail in which a plurality of rolling surfaces of the rolling elements are formed along the longitudinal direction, and a plurality of load rolling rollers that constitute the load passages of the rolling elements facing the rolling surfaces. Each load rolling surface has a pair of crowning regions provided at both ends in the longitudinal direction and an effective load region located between the crowning regions. . The moving block includes at least two types of load rolling surfaces having different boundary positions between the crowning region and the effective load region.

  Since the moving block includes at least two types of load rolling surfaces having different boundary positions between the crowning region and the effective load region, when these two types of load rolling surfaces are compared, the rolling element is effectively removed from the crowning region. The timing of entering the load region is not the same, and is different by an amount corresponding to the displacement amount of the boundary position. Accordingly, in these two types of load rolling surfaces, the rolling elements separate from the effective load region at different timings. Therefore, when all the load rolling surfaces provided in the moving block are considered, the load path The fluctuation of the number of balls existing in the effective load area can be suppressed to a small extent, and the waving generated in the moving block can be suppressed correspondingly, and the moving object that is the object to be conveyed can be guided with high accuracy. It becomes possible.

It is a perspective view which shows 1st embodiment of the rolling guide apparatus which can apply this invention. It is the II-II sectional view taken on the line of the rolling guide apparatus shown in FIG. It is a perspective view which shows the end plate and return piece of the rolling guide apparatus shown in FIG. It is a schematic diagram explaining the structure of the load path | route of the ball | bowl in the rolling guide apparatus shown in FIG. It is the schematic diagram which projected the two load rolling surfaces which function with respect to the radial load F1 on the paper surface. It is the schematic diagram which projected the two load rolling surfaces which function with respect to the lateral load F2 on the paper surface. It is a schematic diagram which shows the load state of the ball | bowl in the two load rolling surface which functions with respect to radial load F1. It is a perspective view which shows 2nd embodiment of the rolling guide apparatus which can apply this invention. It is a front view which shows the track rail of the rolling guide apparatus which concerns on 2nd embodiment. It is front sectional drawing of the rolling guide apparatus which concerns on 2nd embodiment. It is a top view which shows the double row ball coupling body used for the rolling guide apparatus which concerns on 2nd embodiment. It is the schematic diagram which expand | deployed the load rolling surface formed in the movement block which concerns on 2nd embodiment. It is a schematic diagram which shows the other structural example of the load rolling surface pair formed in the movement block which concerns on 2nd embodiment. It is a schematic diagram which shows the example which provided the phase difference between the four double row ball coupling bodies integrated in a moving block.

  Hereinafter, the rolling guide device of the present invention will be described in detail with reference to the accompanying drawings.

  1 and 2 show a first embodiment of a rolling guide apparatus to which the present invention can be applied. This rolling guide device is assembled to the track rail 1 via a long track rail 1 formed in a straight line and a large number of balls 3 as rolling elements, and a moving block having an infinite circulation path for these balls 3. 2, and the ball 3 circulates in the endless circulation path so that the moving block 2 straddles the track rail 1 and freely reciprocates on the track rail 1. ing.

  The track rail 1 is formed in a substantially rectangular cross section perpendicular to the longitudinal direction, and concave portions 10 are formed on both side surfaces along the longitudinal direction. As a result, a jetty 11 is formed on a shoulder portion of each side surface. Has been. Ball rolling surfaces 12 are formed above and below each jetty 11, and four rolling surfaces 12 are formed on the entire track rail. Each rolling surface 12 is inclined at an angle of 45 ° with respect to the bottom surface of the track rail 1, and the rolling surface 12 located above the jetty 11 faces obliquely upward at an angle of 45 °, while The rolling surface 12 located on the side faces obliquely downward at an angle of 45 °. The track rail 1 has fixing bolt mounting holes 13 formed at predetermined intervals along the longitudinal direction, and is used when the track rail 1 is laid on a mechanical device or the like. In addition, the arrangement of the rolling surface 12 with respect to the track rail 1, the inclination angle, and the number of the strips may be appropriately changed according to the load capacity required for the moving block 2. In this example, an example in which a ball is used as a rolling element will be described, but a roller may be used as a rolling element. Furthermore, the track rail of the rolling guide device to which the present invention is applicable is not limited to a linear one, and may be formed in an arc shape with a constant curvature.

  On the other hand, the moving block 2 has a guide groove that accommodates a part of the track rail 1 and is formed in a substantially groove shape, and is arranged so as to straddle the track rail 1. . The moving block 2 includes a metal block main body 4 and a pair of synthetic resin end plates 5 fixed to both end faces of the block main body 4 with the block main body 4 interposed therebetween. The end plate 5 is fixed to the end surface of the block body 4 by mounting bolts 50.

  As shown in FIG. 2, the block body 4 includes a base portion 4a on which a mounting surface 41 such as a mechanical device is formed, and a pair of leg portions 4b orthogonal to the base portion 4a. Yes. A tap hole 42 into which the mounting surface 41 and the fixing bolt are screwed is formed in the base portion 4a, and a load rolling surface 43 on which the ball 3 rolls is formed inside each leg portion 4b. . The rolling surface 12 of the track rail 1 and the load rolling surface 43 of the block body 4 face each other, and a load path through which the ball 3 rolls while applying a load between the moving block 2 and the track rail 1 is provided. Configure. That is, four load rolling surfaces 43 are formed on the block body 4. In this embodiment, the cross section perpendicular to the longitudinal direction of each load rolling surface 43 has a circular arc shape with a slightly larger radius of curvature than the spherical surface of the ball 3, but the shape can be appropriately changed in design. it can. The rolling surface 12 formed on the track rail 1 is also formed in the same circular arc shape. Each leg 4b is formed with four rolling element return passages 44 corresponding to the respective load passages. The cross-sectional shape of the rolling element return passage 44 is larger than the cross-sectional shape of the ball as the rolling element, and the ball 3 rolls in the opposite direction to the inside of the load passage when the ball 3 is released from the load. ing.

  In FIG. 2, reference numeral 45 denotes a seal member that seals between the leg portion 4 b of the block body 4 and the side surface of the track rail 1. Reference numeral 46 denotes a retainer plate screwed to the block body 4 to prevent the ball 3 from rolling off the load passage when the moving block 2 is extracted from the track rail 1.

FIG. 3 is a perspective view showing the end plate 5, which is observed from the contact surface side with the block body 4. The end plate 5 is formed with a plurality of ball guiding grooves 51 that constitute a direction change path of the ball 3. These ball guide grooves 51 are provided corresponding to the respective load rolling surfaces 43 of the block body 4 and are formed at four locations on the end plate 5 so as to surround the track rail 1. Each ball guide groove 51 has a long hole-like opening so as to face the load passage and the ball return passage 44 of the block body 4, and has an outer peripheral guide surface 52 curved in a substantially U shape inside. doing. The outer circumferential guide surface 52 guides the ball 3 between the load passage and the ball return passage 44 and changes the traveling direction of the ball 3 by 180 °. The end of the outer peripheral guide surface 52 facing the track rail 1 is slightly cut out to form a scooping portion 53, which rolls along the load passage while being in contact with the rolling surface 12 of the track rail 1. The balls 3 are accommodated in the ball guiding grooves 51 so as to ride on the scooping portion 53.

  On the other hand, a return piece 6 is fitted in each ball guide groove 51 of the end plate 5. The return piece 6 is formed in a semi-cylindrical shape, and an inner peripheral side guide surface 61 facing the outer peripheral side guide surface 52 in the ball guiding groove 51 is provided as a concave curved surface on the outer peripheral surface. Also, semicircular positioning portions 62 that fit into the end plates are formed on both sides of the inner circumferential guide surface 61, and these positioning portions 62 are located at the center of each ball guide groove 51 of the end plate 4. It fits into a pair of locking grooves 54 formed in. Accordingly, when the positioning portion 62 of the return piece 6 is fitted into the locking groove 54 of the ball guiding groove 51, the return piece 6 is positioned at the center of the ball guiding groove 51, and the outer peripheral side guide provided on the end plate 5 is positioned. The surface 52 and the inner circumferential guide surface 61 provided on the return piece 6 face each other, and the direction change path having an inner diameter larger than the diameter of the ball 5 is completed.

  Then, by fixing the end plate 5 to which the return piece 6 is mounted in this manner to the block body 4, the load passage of the block body 4 and the rolling element return passage 44 are formed by a direction change path formed in a substantially semicircular shape. As a result, the infinite circulation path of the ball 3 is completed on the moving block 2.

  FIG. 4 is a schematic view showing a state of a load passage 47 formed by facing the rolling surface 12 of the track rail and the load rolling surface 43 of the block body. As described above, the rolling surface 12 of the track rail 1 and the load rolling surface 43 of the block body 4 face each other to form the load passage 47, and the ball 3 is connected to the block body 4 and the track rail 1 in the load passage 47. Roll while applying a load acting between and. In order to reduce the occurrence of waving in the moving block 2 due to the entry and exit of the balls 3 with respect to the load passage 47, crowning regions A and B are provided at both ends in the longitudinal direction of the load rolling surface 43 of the block body 4. Are provided. In these crowning regions, the distance between the load rolling surface 43 of the block body 4 and the rolling surface 12 of the track rail 1 gradually increases as it approaches the end of the block body 4 in the longitudinal direction. Further, the region of the load rolling surface 43 sandwiched between the crowning regions A and B is an effective load region C, and is formed in a straight line parallel to the rolling surface 12 of the track rail 1. Therefore, when the ball 3 rolls in FIG. 4 from the left to the right in FIG. 4, the ball 3 that has rolled on the direction change path of the end plate 5 without load is loaded on the load rolling surface 43 of the block body 4. , The crushed area A is gradually crushed between the load rolling surface 43 and the rolling surface 12, and gradually shifts from the no-load state to the loaded state. In the effective load area C, the load is loaded. While rolling. Then, it is gradually released from the load in the crowning region B, and finally enters an unloaded state and enters the direction change path of the end plate 5. In FIG. 4, the end plate 5 is omitted. In FIG. 4, the crowning areas A and B are drawn in a straight line inclined at a predetermined angle with respect to the rolling surface 12 of the track rail 1, but in order to improve the continuity with the effective load area C, It does not matter if it is formed.

  FIG. 5 shows the four load rolling surfaces 43-1 and 43-2 that load the radial load F1 on the track rail 1 among the four load rolling surfaces formed on the block body 4. The load rolling surfaces 43-1 and 43-2 are observed from the action direction of the radial load F1 and projected onto the paper surface. The above-mentioned crowning regions A1 and B1 are provided at both ends in the longitudinal direction of the load rolling surface 43-1, while an effective load region C1 is provided between the crowning regions A1 and B1. In addition, crowning regions A2 and B2 are provided at both ends in the longitudinal direction of the load rolling surface 43-2, while an effective load region C2 is provided between the crowning regions A2 and B2. When the load rolling surface 43-1 and the load rolling surface 43-2 are compared, the effective load regions C1 and C2 have the same length, but the crowning regions A1 and A2 have different lengths by a distance m. In addition, the lengths of the crowning regions B1 and B2 are also different by a distance m.

  That is, the boundary between the crowning region A1 and the effective load region C1 is provided by being displaced by a distance m with respect to the boundary between the crowning region A2 and the effective load region C2. Similarly, the boundary between the crowning region B1 and the effective load region C1 is provided by being displaced by a distance m with respect to the boundary between the crowning region B2 and the effective load region C2. In the first embodiment, the crowning regions A1 and B2 are formed to have the same length, and the crowning regions A2 and B1 are formed to have the same length. Therefore, the load rolling surface 43-1 and the load rolling surface 43-2 have a relationship in which the direction of the longitudinal direction is reversed by 180 °.

  FIG. 6 is a view showing two load rolling surfaces 43-2 and 43-3 that load a lateral load F2 on the track rail 1 among the four load rolling surfaces formed on the block body 4. The load rolling surfaces 43-2 and 43-3 are observed from the acting direction of the lateral load F2 and projected onto the paper surface. The configuration of the load rolling surface 43-3 is the same as the load rolling surface 43-1 described above, and crowning regions A1 and B1 are provided at both ends in the longitudinal direction of the load rolling surface 43-3. An effective load region C1 is provided between the crowning regions A1 and B1. Therefore, the relationship between the load rolling surface 43-2 and the load rolling surface 43-3 is the same as the relationship between the load rolling surface 43-1 and the load rolling surface 43-2 described above. -2 and the load rolling surface 43-3 have a relationship in which the direction of the longitudinal direction is reversed by 180 °.

  Further, although not specifically illustrated, the configuration of the load rolling surface 43-4 located on the opposite side across the load rolling surface 43-3 and the track rail 1 is the same as the above-described load rolling surface 43-2. It is. In other words, the load rolling surface 43-4 is obtained by inverting the longitudinal direction of the load rolling surface 43-1 or the load rolling surface 43-3 by 180 °.

  Accordingly, the four load rolling surfaces provided in the moving block 2 are composed of two types of load rolling surfaces whose longitudinal directions are reversed by 180 °, and these two types of load rolling surfaces. Are aligned, the boundary position between the crowning region and the effective load region C1 is displaced by a distance m.

  The displacement m is set to half of the arrangement pitch of the balls 3 in the endless circulation path, but this is an ideal setting, and any value smaller than the arrangement pitch of the balls is intended for the present invention. It is possible to obtain the effect. Here, the arrangement pitch of the balls 3 is a distance between the centers of the balls 3 rolling back and forth on the endless circulation path. For example, when a spacer is interposed between the adjacent balls 3, the spacer And the diameter of the ball 3 when the balls are in direct contact within the endless circuit.

  FIG. 7 is a schematic diagram showing the load state of the ball 3 rolling on the load rolling surfaces 43-1 and 43-2 when the radial load F1 is acting on the block body 4. As shown in FIG. In the figure, the hatched balls 3 are balls 3 that exist in the effective load region C and are loaded between the track rail 1 and the moving block 2, and the other balls 3. Is a ball 3 which is present in the crowning region A or B and is not completely loaded. In the endless circulation path, there is a slight gap between the front and back balls, and the ball 3 circulates so as to be pushed from the succeeding ball 3 in the rolling element return path and the direction change path. In addition, the timing at which the ball 3 enters the load passage 47 tends to be the same in each infinite circulation path. For this reason, in FIG. 7, it is assumed that the balls 3 that roll on the respective load rolling surfaces 43-1 and 43-2 simultaneously enter the load rolling surface from the direction change path.

  Since the lengths of the crowning regions A1 and A2 provided at the ends of the load rolling surfaces 43-1 and 43-2 differ by half of the arrangement pitch of the balls 3, as shown in FIG. When the ball 3a reaches the boundary position between the crowning region A2 and the effective load region C2 on the rolling surface 43-2 and shifts to the load state, the ball 3b entering the load rolling surface 43-1 simultaneously with the ball 3a is It still exists in the crowning region A1 and has not completely shifted to the load state. On the other hand, when the ball 3c reaches the boundary between the effective load region C1 and the crowning region B1 on the load rolling surface 43-1 and immediately before the transition from the loaded state to the no-load state, the load rolling surface 43 simultaneously with the ball 3c. The ball 3d that has entered -2 has already rolled in the crowning region B2 and is gradually shifting to a no-load state. In FIG. 7A, 16 balls 3 are loaded with the radial load F1 including the two load rolling surfaces 43-1 and 43-2.

  Next, FIG. 7B shows a state in which each ball 3 has advanced on the load rolling surfaces 43-1 and 43-2 by ¼ of the ball diameter as compared with FIG. 7A. Since the ball 3a further enters the effective load region C2, the load does not change, and the center of the ball 3b has not yet reached the center of the crowning region A1 and the effective load region C1, so that the ball 3a remains in an unloaded state. is there. On the other hand, the ball 3c located at the boundary between the effective load region C1 and the crowning region B1 in FIG. 7A has entered the crowning region B1, so that the ball 3c is released from the load state and is free. Transition to a load state. In addition, since the center of the ball 3e immediately after the ball 3d on the load rolling surface 43-2 is still in the effective load region, it is in a load state. That is, in the state of FIG. 7 (b), only the ball 3c shifts from the loaded state to the unloaded state, and as a result, the total number of balls loaded with the radial load F1 decreases by one, Fifteen balls are carrying the radial load F1.

  Further, FIG. 7C shows a state in which each ball 3 travels on the load rolling surfaces 43-1 and 43-2 by 1/4 of the ball diameter as compared with FIG. 7B, that is, FIG. 7A. Compared to FIG. 4, each ball 3 has advanced on the load rolling surfaces 43-1 and 43-2 by ½ of the ball diameter. Although there is no change in the state in which the ball on the loaded rolling surface 43-2 applies a load, the ball 3b newly reaches the boundary between the crowning region A1 and the effective load region C1 on the loaded rolling surface 43-1. The ball 3b shifts to a load state. That is, in the state of FIG. 7 (c), only the ball 3b shifts from the unloaded state to the loaded state, and as a result, the total number of balls loaded with the radial load F1 increases by one, The same 16 balls 3 as in FIG. 7A are carrying the radial load F1.

  If the length of the crowning region A1 of the loaded rolling surface 43-1 and the crowning region A2 of the loaded rolling surface 43-2 are the same, the balls rolling along these loaded rolling surfaces are simultaneously unloaded. Transition from state to load state. Similarly, when the lengths of the crowning region B1 and the crowning region B2 are the same, the balls rolling along the loaded rolling surfaces 43-1 and 43-2 simultaneously shift from the loaded state to the unloaded state. To do. For this reason, as the balls 3 circulate in the infinite circulation path, the total number of balls loaded with the radial load F1 is repeatedly increased and decreased by two.

  However, as shown in FIG. 5, the boundary position between the crowning region and the effective load region is smaller than the arrangement pitch of the balls with respect to the two load rolling surfaces 43-1 and 43-2 that function with respect to the radial load F1. If it is displaced by the distance m, the total number of balls loaded with the radial load F1 will be increased or decreased one by one as the balls are circulated. That is, since the variation in the number of loaded balls due to the circulation of the balls 3 can be suppressed to a small level, the increase / decrease width of the radial load acting on the individual balls 3 can be suppressed accordingly, and the movement block 2 relative to the track rail 1 can be suppressed. It becomes possible to suppress waving.

  This also applies to the load rolling surfaces 43-2 and 43-3 that load the lateral load F2, and the balls that roll in the effective load regions C2 and C3 of the load rolling surfaces 43-2 and 43-3. The total number of is only increased or decreased one by one even if the ball enters and exits the load rolling surface with infinite circulation. Accordingly, the fluctuation in the number of load balls accompanying the circulation of the balls 3 can be suppressed to a small level, and therefore the increase / decrease width of the lateral load F2 acting on the individual balls 3 can be suppressed correspondingly, and the moving block 2 relative to the track rail 1 can be suppressed. It becomes possible to suppress the waving.

  When the moving block 2 of the first embodiment is observed, the moving block 2 has two sets of four rolling rolling surfaces, with the two rolling rolling surfaces having different boundary positions as one set. Will be. For example, when considering the load rolling surface that functions with respect to the radial load F1, the load rolling surfaces of the two strips that form the set are the load rolling surface 43-1 and the load rolling surface 43-2. It becomes two sets of the surface 43-3 and the load rolling surface 43-4. On the other hand, when the load rolling surface which functions with respect to the lateral load F2 is considered, the load rolling surface 43-2 and the load rolling surface 43-3, the load rolling surface 43-1 and the load rolling surface 43-3. It becomes two sets of.

  In this way, if two load rolling surfaces that function with respect to a load in a predetermined direction are set as one set, and the boundary positions of the crowning region and the effective load region on these two load rolling surfaces are different from each other, It is possible to effectively suppress the occurrence of waving of the moving block 2 with respect to the load in the direction. Thereby, in the rolling guide device of the first embodiment, it is possible to reduce the waving of the moving block 2 with respect to the track rail 1 with respect to loads in all directions acting in a plane perpendicular to the track rail 1.

  In addition, the length of the effective load region C is the same on all the load rolling surfaces, and the length of the crowning region located at one end of the effective load region is different from the length of the crowning region located at the other end by a distance m. . In other words, in the moving block 2 of the first embodiment, the load rolling surface where the effective load region C is formed adjacent to each other in the load rolling surfaces 43-1, 43-2, 43-3 and 43-4. It is displaced by a distance m which is half the arrangement pitch of the balls 3. For this reason, by providing two types of load rolling surfaces with different boundary positions, it is possible to reduce the waving that occurs in the moving block 2 and maintain the load-loading capacity of the moving block 2 without changing from the conventional one. .

  In the rolling guide device according to the first embodiment, in order to more effectively suppress the waving that occurs in the moving block 2, balls that roll on two sets of adjacent load rolling surfaces are in contact with each other. It is desirable to synchronize the timing of entering the surface. For example, two rows of balls 3 rolling on the load rolling surfaces 43-1 and 43-4 are arranged in a belt-like double row ball connection body as shown in JP-A-10-2332 and load rolling The two rows of balls 3 rolling on the surfaces 43-2 and 43-3 are also arranged in a similar double row ball coupling body, and these double row ball coupling bodies are incorporated into the endless circulation path of each sleeve 4b of the moving block 2. It is possible. By arranging two rows of balls 3 in parallel for each double row ball coupling body, for example, the timing at which the balls 3 enter the respective load rolling surfaces 43-1 and 43-4 is synchronized, When the load rolling surface 43-1 and the load rolling surface 43-4 are compared, the timing at which the ball 3 enters and exits the effective load region C1 or C2 is always different. The generated waving can be effectively reduced.

  FIG. 8 shows a second embodiment of a rolling guide apparatus to which the present invention is applicable.

Similarly to the rolling guide apparatus described as the first embodiment, the rolling guide apparatus of the second embodiment is also described above through a long track rail 100 formed in a straight line and a large number of balls as rolling elements. The moving block 200 is assembled to the track rail 100 and has an infinite circulation path for these balls. The ball circulates in the endless circulation path so that the moving block 200 can reciprocate freely on the track rail 100 so as to straddle the track rail 100.

  The moving block 200 has a guide groove that accommodates a part of the track rail 100 and is formed in a substantially groove shape, and is arranged so as to straddle the track rail 100. The moving block 200 includes a metal block main body 400 and a pair of synthetic resin end plates 500 fixed to both end faces of the block main body 400 with the block main body 400 interposed therebetween. The track rail 100 has a rectangular cross section perpendicular to the longitudinal direction, and is provided with a plurality of bolt mounting holes 130 at regular intervals along the longitudinal direction.

  As shown in FIG. 9, the track rail 100 is formed with a plurality of ball rolling surfaces 101a and 101b along the longitudinal direction of the track rail. Thus, a rolling surface pair is formed, and four rolling surface pairs 102A to 102D are provided on the track rail. Two sets of rolling surface pairs 102A and 102B are formed on the upper surface of the track rail 100 with the bolt mounting hole 130 interposed therebetween, and the rolling surface pair is also formed on each side surface along the longitudinal direction of the track rail 100. 102C and 102D are formed. The two rolling contact surfaces 101a and 101b constituting each rolling contact pair 102A to 102D are inclined at the same angle with respect to the bottom surface 103 of the track rail 100. In other words, the contact angle direction with the ball 3 is the same. The two rolling surfaces 101a and 101b function in the same way with respect to a load in a specific direction and have a relationship of complementing each other. For example, the rolling contact surface located on the upper surface of the track rail 100 has a contact angle with the ball set to 45 ° obliquely upward, while the rolling contact surface positioned on the side surface of the track rail has a contact angle with the ball obliquely downward. Is set to 45 °. The arrangement and inclination angle of the rolling surfaces 101a and 101b with respect to the track rail 100 may be appropriately changed according to the load capacity required for the moving block 200. In this example, an example in which a ball is used as a rolling element will be described, but a roller may be used as a rolling element.

  As shown in FIG. 10, the block main body 400 includes a base portion 400a on which a mounting surface 410 such as a mechanical device is formed, and a pair of leg portions 400b orthogonal to the base portion 400a, and has a substantially groove-shaped cross section. . A tap hole 420 into which the mounting surface 410 and the fixing bolt are screwed is formed in the base 400a (see FIG. 8). A plurality of load rolling surfaces 401a and 401b facing the rolling surfaces 101a and 101b of the track rail 100 are formed at positions of the base portion 400a and the pair of leg portions 400b facing the track rail 100. These load rolling surfaces 401 a and 401 b also constitute two sets of load rolling surface pairs 402 A to 402 D corresponding to the rolling surface pairs 102 A to 102 D of the track rail 100. That is, the base 400a is provided with load rolling surface pairs 402A and 402B corresponding to the rolling surface pairs 102A and 102B of the track rail 100, and the leg portions are connected to the rolling surface pairs 102C and 102D of the track rail 100, respectively. Corresponding load rolling surface pairs 402C and 402D are arranged.

  Two rows of balls rolling on the two load rolling contact surfaces 401 a and 401 b included in each of the load rolling contact surface pairs 402 </ b> A to 402 </ b> D are arranged in a belt-like double row ball coupling body 300. FIG. 11 is a plan view showing a part of the double row ball coupling body 300. This double row ball coupling body 300 is manufactured by injection molding of synthetic resin, and the balls 3 are arranged in two rows in parallel, and each ball row is a load rolling included in the load rolling surface pairs 402A to 402D. It corresponds to the surfaces 401a and 401b. The double row ball coupling body 300 includes a plurality of spacers 302 and a belt portion 303 having flexibility for coupling the spacers 302 to each other. The spacers 302 are provided between the balls 3 constituting each ball row. Is provided. Thereby, each ball 3 is rotatably held by a pair of spacers 302. This double row ball coupling body 300 is incorporated in the endless circulation path of the moving block 200 together with the balls, and the ball 3 moves in the longitudinal direction as it rolls on the load rolling surfaces 401a and 401b. Circulate in an infinite circuit. The double-row ball coupling body 300 is not connected endlessly in the endless circulation path of the moving block 200, and one end and the other end in the longitudinal direction face each other with a space therebetween.

  In order to form an infinite circulation path into which the double row ball coupling body 300 can be incorporated, a belt return path 403 is formed in the block body 400 corresponding to each load rolling surface pair 402A to 402D. These belt return passages 403 have a cross-sectional shape through which the ball coupling body 300 can pass with a slight gap. The belt return passage 403 forms a through hole having a diameter larger than the width of the double row ball coupling body 300 in the block body 400, and then injection-molds synthetic resin on the inner peripheral surface of the through hole. It is produced by.

  When the end plate 500 having direction change paths is fixed to both end faces of the block body 400, the belt return path 403 of the block body and the direction change path are connected to each other, and the ball coupling body 300 is infinitely circulated. The moving block 200 having a road is completed.

  FIG. 12 is a schematic diagram illustrating the eight loaded rolling surfaces formed on the block body 400 of the moving block 200. As described above, the block main body 400 is formed with the load rolling surface pairs 402A to 402D in which two load rolling surfaces 401a and 401b adjacent to each other are set as one set. Similarly to the first embodiment described above, crowning areas A1 and B1 are provided at both ends in the longitudinal direction of each load rolling surface 401a, while an effective load area C1 is provided between the crowning areas A1 and B1. Yes. In addition, crowning regions A2 and B2 are provided at both ends in the longitudinal direction of each load rolling surface 401b, while an effective load region C2 is provided between the crowning regions A2 and B2. When comparing the load rolling surface 401a and the load rolling surface 401b, the effective load regions C1 and C2 have the same length, but the crowning regions A1 and A2 have different lengths by a distance m, The lengths of the crowning regions B1 and B2 are also different by the distance m. This displacement m is set to half of the arrangement pitch of the balls 3 in the endless circulation path as in the first embodiment, and here is half of the arrangement pitch P of the balls in the double row ball coupling body 300 (FIG. 11). However, this is the most preferable setting value, and the displacement amount m may be a value smaller than the ball arrangement pitch P.

  As shown in FIG. 11, the two rows of balls arranged in a parallel positional relationship with the double row ball coupling body 300 are adjacent to each other in the direction orthogonal to the rolling direction (the one-dot chain line X direction). If the length of the crowning region A1 of the load rolling surface 401a and the crowning region A2 of the load rolling surface 401b are the same, that is, if the displacement amount m is not set, it is arranged in the double row ball coupled body 300. The two rows of balls 3 simultaneously shift from the no-load state to the load state. Similarly, when the lengths of the crowning region B1 and the crowning region B2 are the same, the balls 3 rolling along the load rolling surfaces 401a and 401b simultaneously shift from the loaded state to the unloaded state. For this reason, as the ball coupled body 300 circulates in the infinite circulation path, the total number of balls loaded with loads in each of the load rolling surface pairs 402A to 402D is repeatedly increased and decreased by two.

  However, as shown in FIG. 12, with respect to the two load rolling contact surfaces 401a and 401b constituting each load rolling contact surface pair 402A to 402D, the boundary position between the crowning region and the effective load region is set as the arrangement pitch of the balls 3. For the same reason as in the first embodiment described above, the total number of balls 3 to which a load is applied in each load rolling surface pair 402A to 402D is associated with the circulation of the balls. Will increase and decrease one by one.

Therefore, in the rolling guide device of the second embodiment, even if the double row ball coupling body 300 circulates in the infinite circulation path of the moving block 200, the load ball number variation in each load rolling surface pair 402A to 402D is reduced. Since it can be suppressed to be small, the increase / decrease width of the load acting on each ball 3 can be suppressed correspondingly, and the waving of the moving block 200 with respect to the track rail 100 can be suppressed.

  In particular, in the rolling guide device according to the second embodiment, the two load rolling surfaces 401a and 401b constituting the load rolling surface pair 402A function in the same manner with respect to a load in a specific direction and complement each other. Since there is a relationship, even if the boundary position between the crowning region and the effective load region is displaced in this way, there is no change in the load carrying capacity for each load rolling surface pair. For this reason, it is possible to effectively suppress the waving of the moving block 200 without any reduction in the load capacity as the rolling guide device.

  Further, in the rolling guide device of the second embodiment, the double row ball coupling body 300 is provided for each load rolling surface pair, and the balls 3 rolling on the two load rolling surfaces 401a and 401b are as follows. Since the double row ball coupling body 300 is arranged in parallel in two rows, the balls rolling on the load rolling surfaces 401a and 401b always enter the load rolling surface at the same time. For this reason, it becomes possible to suppress the waving of the moving block 200 more effectively by displacing the boundary position between the crowning region and the effective load region.

  In the example shown in FIG. 12, the lengths of the effective load areas C1 and C2 on the two load rolling surfaces 401a and 401b constituting the load rolling surface pair 402A are the same, and are positioned at both ends of each effective load region. The effective load regions C1 and C2 were displaced in the longitudinal direction by a distance m which is half the ball arrangement pitch by changing the length of the crowning region to be performed. However, the present invention is not limited to this, and as shown in FIG. 13, the lengths of the crowning regions A1 and B1, and the lengths of A2 and B2 at both ends of the effective load region are the same, and the lengths of the crowning regions C1 and C2 are made different. You may do it. Even in the example shown in FIG. 13, the boundary position between the crowning region and the effective load region on the load rolling surface 401a is displaced by a distance m that is half the ball arrangement pitch with respect to that of the load rolling surface 401b. As in the case shown in FIG. 12, the effect of reducing waving can be obtained.

  Next, FIG. 14 is a diagram showing the positional relationship of the four double row ball coupling bodies 300A to 300D incorporated in the moving block 20 corresponding to the respective load rolling surface pairs 402A to 402D. When incorporating these double-row ball assemblies into the moving block 200, it is possible to obtain the aforementioned effect of reducing the waving of the moving block 200 regardless of the mutual positional relationship of the double-row ball assemblies. However, as shown in FIG. 14, four double row ball coupling bodies 300A to 300D corresponding to the load rolling surface pairs 402A to 402D are incorporated into an infinite circuit with a phase difference of (1/4) m. This makes it possible to more effectively suppress the waving that occurs in the moving block 200. In FIG. 14, the double row ball coupled body 300C corresponding to the load rolling surface pair 402C has a phase difference of (1/4) m with reference to the double row ball coupled body 300A corresponding to the load rolling surface pair 402A. In addition, the double row ball coupling body 300D corresponding to the load rolling surface pair 402D has a phase difference of (1/2) m. Moreover, the double row ball coupling body 300B corresponding to the load rolling surface pair 402B has a phase difference of (3/4) m. Here, the phase difference m is the ball arrangement pitch with respect to the double row ball coupling body as described above.

  Thus, in each load rolling surface pair, the effective load areas C1 and C2 of the load rolling surface 401a and the load rolling surface 401b are relatively displaced along the rolling direction of the ball, and the moving block 200 It is possible to more effectively reduce the waving of the moving block 200 caused by the infinite circulation of the balls by providing a phase difference in the mutual positional relationship of the plurality of double row ball coupling bodies 300A to 300D incorporated in It becomes.

  According to the results verified by the present inventors, the amount of waving amplitude in the radial direction of the moving block 200 in the rolling guide device of the second embodiment is between the four double-row ball coupling bodies 300A to 300D. When the phase difference was not provided, it became 1/7 or less of that of the rolling guide device having the same 8 load rolling surfaces. In addition, when a phase difference is provided between the four double-row ball coupling bodies 300A to 300D, the amount of waving amplitude in the radial direction of the moving block 200 is ½ or less that when no phase difference is provided. The effectiveness of the invention could be confirmed.

  In the first embodiment and the second embodiment described above, the rolling guide device in which the moving block has an infinite circulation path of a ball as a rolling element has been described as an application object of the present invention. As described above, if the moving block forms a load path between the track rail and the rolling guide device in which the ball enters and exits the load path, the application object of the present invention includes an infinite circulation path of the ball. It is not limited to a rolling guide device. For example, a ball cage in which a large number of balls are arranged is formed longer than the moving block, the ball cage is interposed between the track rail and the moving block, and the moving block moves with respect to the track rail. The present invention can also be applied to a rolling guide device in which balls arranged in the ball cage enter the load passage, that is, a so-called finite stroke type rolling guide device.

  DESCRIPTION OF SYMBOLS 1 ... Track rail, 2 ... Moving block, 3 ... Ball, 12 ... Rolling surface, 43 ... Load rolling surface

Claims (7)

A track rail in which a plurality of rolling surfaces of the rolling elements are formed along the longitudinal direction, and a moving block having a plurality of load rolling surfaces that constitute the load passages of the rolling elements facing the rolling surfaces,
Each rolling rolling surface is a rolling guide device having a pair of crowning regions provided at both ends in the longitudinal direction and an effective load region located between these crowning regions.
The rolling guide device according to claim 1, wherein the moving block includes at least two types of load rolling surfaces having different boundary positions between the crowning region and the effective load region.   2. The two load rolling surfaces having different boundary positions between the crowning region and the effective load region are set as one set, and the moving block includes a plurality of sets of load rolling surfaces. Rolling guide device.   The means for synchronizing the entry timing to the load rolling surface with respect to the two rows of rolling elements that roll on the two load rolling surfaces are adjacent to each other. The rolling guide apparatus according to claim 2, wherein the rolling guide apparatus is provided.   The moving block has an infinite circulation path of rolling elements that roll in the load passage, while the synchronizing means is a flexible double row ball connection body in which two rows of rolling elements are arranged in parallel. 4. The rolling guide device according to claim 3, wherein the ball coupling body is incorporated in the endless circulation path of the moving block together with the rolling element.   The rolling guide device according to claim 4, wherein the length of the effective load region is the same on all load rolling surfaces.   6. The rolling guide device according to claim 5, wherein the two load rolling surfaces forming the set have the same contact angle direction with the rolling elements.   3. The rolling guide device according to claim 2, wherein a displacement amount of the boundary position on the two load rolling surfaces forming a set is a half of a ball arrangement pitch in the infinite circulation path.

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